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||<10% style="text-align:center">'''PIRA #''' ||<style="text-align:center">'''Demonstration Name''' ||<60% style="text-align:center">'''Abstract''' ||
||6A01.10 ||speed of light ||Demonstrate speed of light by the path difference method with a fast pulser and fast oscilloscope. ||
||6A01.10 ||speed of light ||A fast pulser is used to demonstrate speed of light by the path difference method. ||
||6A01.10 ||velocity of light ||The displacement of a pulse from a fast pulser is viewed on a sampling oscilloscope as the path length is changed. Insert different media in the path. ||
||6A01.10 ||speed of light - moving reflector ||Fancy speed of light apparatus fully documented. Diagrams, Pictures. ||
||6A01.11 ||pulser circuit ||A pulser circuit for the moving reflector speed of light apparatus. ||
||6A01.11 ||speed of light - fast pulse ||Use a high repetition rate pulsed light from TRW to demonstrate the speed of light. ||
||6A01.11 ||pulser circuit ||An LED pulser circuit that emits a 20 ns pulse. ||
||6A01.11 ||pulser circuit ||A light pulser circuit based on the MV 10A LED. ||
||6A01.11 ||speed of light - N2 laser pulser ||A N2 pulsed laser is used in the moving reflector setup. ||
||6A01.12 ||speed of light - spark source ||Construction and properties of a spark light source. ||
||6A01.15 ||microwave moving reflector ||A small microwave pulse generator gives short pulses. ||
||6A01.20 ||speed of light - two path ||Fast flash through two paths to a photomultiplier tube. Diagrams, Pictures. ||
||6A01.21 ||speed of light - two path ||A spot of the display trace of a fast oscilloscope is passed through two different paths to a photomultiplier tube whose output is displayed on the same trace. Diagram, Picture. ||
||6A01.25 ||errata - corrected diagram ||Corrected diagram for figure 2 in AJP 37(8),818 (1969). ||
||6A01.25 ||speed on light ||The MV50 LED is pulsed in this simple time of flight measurement. ||
||6A01.25 ||speed of light - minimal apparatus ||An inexpensive time of flight apparatus using a strobed LED and voltmeter. ||
||6A01.25 ||speed of light - time of flight ||An acoustico-optic modulator chops a laser beam in a time of flight setup. ||
||6A01.25 ||speed of light choppers ||Use a 250 tooth commercial gear as a light chopper. ||
||6A01.26 ||speed of light - phase shift ||Many circuits are given. Features a solid-state electro-optical light modulator to replace the Kerr cell. ||
||6A01.27 ||optical radar ||A commercial (Optitron Inc.) speed of light apparatus with an ultraviolet pulser. ||
||6A01.30 ||speed of light - rotating mirror ||The position of the reflected image from a rotating mirror is measured for clockwise and counterclockwise rotations. Diagram, Appendix, p. 1353. ||
||6A01.31 ||speed of light - rotating mirror ||Photodiode detector with the rotating mirror. ||
||6A01.31 ||speed of light - rotating mirror ||A laser beam is used with the rotating mirror method. Detector circuits given. ||
||6A01.32 ||speed of light - combined method ||A rotating mirror chops the laser beam and a beam splitter gives near and far paths. ||
||6A01.36 ||Leybold speed of light modification ||When both sides of the rotating mirror are exposed, deflections as large as 2 cm can be observed with the unaided eye. ||
||6A01.36 ||Leybold speed of light rotation rate ||Instead of comparing the motor sound to a tuning fork, use a microphone to pick up the motor sound and display it on an oscilloscope, use Lissajous figures with a reference. ||
||6A01.36 ||more Leybold improvements ||Use a solar cell with the AJP 32(7),567 technique. ||
||6A01.36 ||Leybold speed of light improvements ||Find the lateral displacement of the returning beam with a photomultiplier on a carriage. ||
||6A01.36 ||Leybold speed of light improvements ||Use a microphone, oscillator, and oscilloscope to measure the motor frequency of the Leybold speed of light apparatus. Reference: AJP 29(10),711. ||
||6A01.38 ||speed of light - microwave interfer. ||The Doppler beat frequency from the detector is used to drive a spark generator. ||
||6A01.40 ||speed of light - models ||Set up mirrors on the lab bench to help students visualize the standard methods. Do the sound analog (S-81). Set up a rotating mirror. ||
||6A01.50 ||group velocity of light ||Measure the speed of light to 0.02% and verify the relationship between group and phase velocity. Low cost circuit is given. ||
||<10% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''PIRA #''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Demonstration Name''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Subsets''' ||<60% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''Abstract''' ||
||6A01.10 ||speed of light || ||Demonstrate speed of light by the path difference method with a fast pulser and fast oscilloscope. ||
||6A01.10 ||speed of light ||pira200 ||A circuit generates a rapped light pulse that is sent through a fiber optic wire of (20m & 0.1m). The speed of light is shown on oscilloscope by comparing two difference lengths of fiber to a reference signal. ||
||6A01.10 ||velocity of light || ||The displacement of a pulse from a fast pulser is viewed on a sampling oscilloscope as the path length is changed. Insert different media in the path. ||
||6A01.10 ||speed of light - moving reflector || ||Fancy speed of light apparatus fully documented. Diagrams, Pictures. ||
||6A01.11 ||pulser circuit || ||A pulser circuit for the moving reflector speed of light apparatus. ||
||6A01.11 ||speed of light - fast pulse || ||Use a high repetition rate pulsed light from TRW to demonstrate the speed of light. ||
||6A01.11 ||pulser circuit || ||An LED pulser circuit that emits a 20 ns pulse. ||
||6A01.11 ||pulser circuit || ||A light pulser circuit based on the MV 10A LED. ||
||6A01.11 ||speed of light - N2 laser pulser || ||A N2 pulsed laser is used in the moving reflector setup. ||
||6A01.12 ||speed of light - spark source || ||Construction and properties of a spark light source. ||
||6A01.15 ||microwave moving reflector || ||A small microwave pulse generator gives short pulses. ||
||6A01.20 ||speed of light - two path || ||Fast flash through two paths to a photomultiplier tube. Diagrams, Pictures. ||
||6A01.21 ||speed of light - two path || ||A spot of the display trace of a fast oscilloscope is passed through two different paths to a photomultiplier tube whose output is displayed on the same trace. Diagram, Picture. ||
||6A01.25 ||errata - corrected diagram || ||Corrected diagram for figure 2 in AJP 37(8),818 (1969). ||
||6A01.25 ||speed on light || ||The MV50 LED is pulsed in this simple time of flight measurement. ||
||6A01.25 ||speed of light - minimal apparatus || ||An inexpensive time of flight apparatus using a strobed LED and voltmeter. ||
||6A01.25 ||speed of light - time of flight || ||An acoustico-optic modulator chops a laser beam in a time of flight setup. ||
||6A01.25 ||speed of light choppers || ||Use a 250 tooth commercial gear as a light chopper. ||
||6A01.26 ||speed of light - phase shift || ||Many circuits are given. Features a solid-state electro-optical light modulator to replace the Kerr cell. ||
||6A01.27 ||optical radar || ||A commercial (Optitron Inc.) speed of light apparatus with an ultraviolet pulser. ||
||6A01.30 ||speed of light - rotating mirror || ||The position of the reflected image from a rotating mirror is measured for clockwise and counterclockwise rotations. Diagram, Appendix, p. 1353. ||
||6A01.31 ||speed of light - rotating mirror || ||Photodiode detector with the rotating mirror. ||
||6A01.31 ||speed of light - rotating mirror || ||A laser beam is used with the rotating mirror method. Detector circuits given. ||
||6A01.32 ||speed of light - combined method || ||A rotating mirror chops the laser beam and a beam splitter gives near and far paths. ||
||6A01.36 ||Leybold speed of light modification || ||When both sides of the rotating mirror are exposed, deflections as large as 2 cm can be observed with the unaided eye. ||
||6A01.36 ||Leybold speed of light rotation rate || ||Instead of comparing the motor sound to a tuning fork, use a microphone to pick up the motor sound and display it on an oscilloscope, use Lissajous figures with a reference. ||
||6A01.36 ||more Leybold improvements || ||Use a solar cell with the AJP 32(7),567 technique. ||
||6A01.36 ||Leybold speed of light improvements || ||Find the lateral displacement of the returning beam with a photomultiplier on a carriage. ||
||6A01.36 ||Leybold speed of light improvements || ||Use a microphone, oscillator, and oscilloscope to measure the motor frequency of the Leybold speed of light apparatus. Reference: AJP 29(10),711. ||
||6A01.38 ||speed of light - microwave interfer. || ||The Doppler beat frequency from the detector is used to drive a spark generator. ||
||6A01.40 ||speed of light - models || ||Set up mirrors on the lab bench to help students visualize the standard methods. Do the sound analog (S-81). Set up a rotating mirror. ||
||6A01.50 ||group velocity of light || ||Measure the speed of light to 0.02% and verify the relationship between group and phase velocity. Low cost circuit is given. ||
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||<10% style="text-align:center">'''PIRA #''' ||<style="text-align:center">'''Demonstration Name''' ||<60% style="text-align:center">'''Abstract''' ||
||6A02.10 ||light in a vacuum ||Place a flashing light in the bell jar to emphasize the point. ||
||6A02.15 ||straight line propagation - shadows || ||
||6A02.15 ||straight line propagation of light ||A good point source shows straight line propagation of light by shadow projection. ||
||6A02.15 ||straight line propagation ||Cast shadows with a point source. ||
||6A02.16 ||propagation star ||An intense radiation point source limited by a star shaped aperture melts a star shaped pattern on a paraffin backed black foil. ||
||6A02.35 ||chalk dust || ||
||<10% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''PIRA #''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Demonstration Name''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Subsets''' ||<60% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''Abstract''' ||
||6A02.10 ||light in a vacuum || ||Place a flashing light in the bell jar to emphasize the point. ||
||6A02.15 ||straight line propagation - shadows || || ||
||6A02.15 ||straight line propagation of light || ||A good point source shows straight line propagation of light by shadow projection. ||
||6A02.15 ||straight line propagation || ||Cast shadows with a point source. ||
||6A02.16 ||propagation star || ||An intense radiation point source limited by a star shaped aperture melts a star shaped pattern on a paraffin backed black foil. ||
||6A02.35 ||chalk dust || || ||
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||<10% style="text-align:center">'''PIRA #''' ||<style="text-align:center">'''Demonstration Name''' ||<60% style="text-align:center">'''Abstract''' ||
||6A10.05 ||optical design software ||Use commercial optical design software to model and display geometrical optics. ||
||6A10.09 ||reflection model ||A string and pulley arrangement shows the minimum path for reflection from a flat surface. ||
||6A10.10 ||blackboard optics - plane mirror ||Blackboard optics - plane mirror. ||
||6A10.11 ||optical disk with flat mirror ||Use a single beam with the optical disk and a flat mirror element. ||
||6A10.11 ||optical disk with flat mirror ||Turn the optical disk with a single beam of light hitting the mirror. ||
||6A10.11 ||angle of incidence, reflection ||Aim a beam of light at a mirror at the center of a disc, rotate the disc. ||
||6A10.15 ||laser and flat mirror ||Shine a laser at a flat mirror on the lecture bench and use chalk dust to make the beam visible. ||
||6A10.18 ||microwave reflection ||Reflect a microwave beam off a metal plate into a receiver. ||
||6A10.20 ||smooth and rough surface reflection ||Chalk dust sprinkled on a mirror blurs the image of a light reflecting onto the wall. ||
||6A10.20 ||diffuse/specular reflection ||Show a beam on light reflecting off a mirror on an optics board. Replace the mirror with a sheet of paper. ||
||6A10.21 ||diffuse reflection ||Hold frosted glass at various angles in a beam of light focused on the wall. ||
||6A10.22 ||aluminum foil reflection ||Same as AJP 50(5),473. ||
||6A10.22 ||scattering with aluminum foil ||Reflect light off a sheet of aluminum foil, then crumple and flatten it to create many facets. ||
||6A10.24 ||reflection - normal and grazing ||Place a lantern and piece of clear glass midway between two walls and show the difference between reflecting by grazing on one wall and normal reflection on the other. Also compare glass and silvered at grazing and normal incidence. ||
||6A10.25 ||ripple tank reflection || ||
||6A10.30 ||corner reflector ||Three reflectors are placed on the inside corner of a box. ||
||6A10.30 ||corner cube ||Two mirrors at 90 degrees or three mirrors mutually perpendicular. ||
||6A10.30 ||corner reflection ||Look at your image in a corner cube. ||
||6A10.31 ||large corner cube ||Use large mirror wall tiles (12 in sq) to make a large corner reflector. ||
||6A10.33 ||signaling mirror ||A plane mirror with a small unsilvered area in the center is used for signaling. Diagram. ||
||6A10.35 ||perversion ||Perversion can be demonstrated in public with a license plate and a plane mirror. Sorry, no inversion. ||
||6A10.37 ||parity reversal in a mirror ||View a Cartesian coordinate system in a mirror. ||
||6A10.40 ||mirrors at an angle ||A candle placed between angled mirrors forms multiple images. ||
||6A10.40 ||angled mirrors ||Two hinged front surface mirrors show multiple images of an object placed between them. Diagram. ||
||6A10.40 ||hinged mirrors ||Mirrors angled at 60 degrees give one object and five images arranged in a hexagon. ||
||6A10.41 ||hinged mirrors ||Place a light between two mirrors hinged together and standing vertically. Place a sheet of clear glass between the mirrors forming an isosceles triangle. A few more variations are given. ||
||6A10.42 ||hinged mirrors, kaleidoscopes ||Hinged mirrors are shown at 60 and 30 degrees along with 60 and 30 degree kaleidoscopes. ||
||6A10.43 ||angled mirrors - laser spots ||The hyperboloid of revolution formed by the successive reflections of a laser beam on two plane angled mirrors is explained by a simple geometrical method. ||
||6A10.44 ||hinged mirrors theory ||The theorem of Rosendahl is applied to the hinged mirror problem to predict the number of images formed at various inclinations. ||
||6A10.45 ||parallel mirrors ||An infinite number of images are formed with a candle between parallel images. ||
||6A10.45 ||barbershop mirrors ||Place objects between parallel mirrors and view them over one of the mirrors. ||
||6A10.50 ||full view mirror || ||
||6A10.50 ||height of a mirror for full view ||Shades are pulled up from the bottom and down from the top covering a mirror until a person can just see their entire height. ||
||6A10.51 ||large plane mirror ||A three foot plane mirror is used to show all of a six foot person. ||
||6A10.60 ||candle in a glass of water ||A candle in front of a plate glass forms an image in a glass of water behind. ||
||6A10.60 ||plane mirror ||A candle is placed in front of a sheet of glass and a beaker of water an equal distance behind. Place the entire apparatus on a rotating table. ||
||6A10.60 ||location of image ||Place a sheet of glass between a burning candle and a glass of water so the image of the candle appears in the glass. ||
||6A10.65 ||half silvered mirror box || ||
||6A10.65 ||Mirror Box ||Two people look into opposite ends of a box containing a half silvered mirror in the center. As the light on one end is dimmed, the light on the other brightens, causing metamorphosis. ||
||6A10.76 ||sawblade optics ||Keep the sawblade perpendicular by lining up the reflection of the board in the sawblade. ||
||<10% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''PIRA #''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Demonstration Name''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Subsets''' ||<60% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''Abstract''' ||
||6A10.05 ||optical design software || ||Use commercial optical design software to model and display geometrical optics. ||
||6A10.09 ||reflection model || ||A string and pulley arrangement shows the minimum path for reflection from a flat surface. ||
||6A10.10 ||blackboard optics - plane mirror || ||Blackboard optics - plane mirror. ||
||6A10.11 ||optical disk with flat mirror || ||Use a single beam with the optical disk and a flat mirror element. ||
||6A10.11 ||optical disk with flat mirror || ||Turn the optical disk with a single beam of light hitting the mirror. ||
||6A10.11 ||angle of incidence, reflection || ||Aim a beam of light at a mirror at the center of a disc, rotate the disc. ||
||6A10.15 ||laser and flat mirror || ||Shine a laser at a flat mirror on the lecture bench and use chalk dust to make the beam visible. ||
||6A10.18 ||microwave reflection || ||Reflect a microwave beam off a metal plate into a receiver. ||
||6A10.20 ||smooth and rough surface reflection || ||Chalk dust sprinkled on a mirror blurs the image of a light reflecting onto the wall. ||
||6A10.20 ||diffuse/specular reflection || ||Show a beam on light reflecting off a mirror on an optics board. Replace the mirror with a sheet of paper. ||
||6A10.21 ||diffuse reflection || ||Hold frosted glass at various angles in a beam of light focused on the wall. ||
||6A10.22 ||aluminum foil reflection || ||Same as AJP 50(5),473. ||
||6A10.22 ||scattering with aluminum foil || ||Reflect light off a sheet of aluminum foil, then crumple and flatten it to create many facets. ||
||6A10.24 ||reflection - normal and grazing || ||Place a lantern and piece of clear glass midway between two walls and show the difference between reflecting by grazing on one wall and normal reflection on the other. Also compare glass and silvered at grazing and normal incidence. ||
||6A10.25 ||ripple tank reflection || || ||
||6A10.30 ||corner reflector || ||Three reflectors are placed on the inside corner of a box. ||
||6A10.30 ||corner cube || ||Two mirrors at 90 degrees or three mirrors mutually perpendicular. ||
||6A10.30 ||corner reflection || ||Look at your image in a corner cube. ||
||6A10.31 ||large corner cube || ||Use large mirror wall tiles (12 in sq) to make a large corner reflector. ||
||6A10.33 ||signaling mirror || ||A plane mirror with a small unsilvered area in the center is used for signaling. Diagram. ||
||6A10.35 ||perversion || ||Perversion can be demonstrated in public with a license plate and a plane mirror. Sorry, no inversion. ||
||6A10.37 ||parity reversal in a mirror || ||View a Cartesian coordinate system in a mirror. ||
||6A10.40 ||mirrors at an angle || ||A candle placed between angled mirrors forms multiple images. ||
||6A10.40 ||angled mirrors || ||Two hinged front surface mirrors show multiple images of an object placed between them. Diagram. ||
||6A10.40 ||hinged mirrors || ||Mirrors angled at 60 degrees give one object and five images arranged in a hexagon. ||
||6A10.41 ||hinged mirrors || ||Place a light between two mirrors hinged together and standing vertically. Place a sheet of clear glass between the mirrors forming an isosceles triangle. A few more variations are given. ||
||6A10.42 ||hinged mirrors, kaleidoscopes || ||Hinged mirrors are shown at 60 and 30 degrees along with 60 and 30 degree kaleidoscopes. ||
||6A10.43 ||angled mirrors - laser spots || ||The hyperboloid of revolution formed by the successive reflections of a laser beam on two plane angled mirrors is explained by a simple geometrical method. ||
||6A10.44 ||hinged mirrors theory || ||The theorem of Rosendahl is applied to the hinged mirror problem to predict the number of images formed at various inclinations. ||
||6A10.45 ||parallel mirrors || ||An infinite number of images are formed with a candle between parallel images. ||
||6A10.45 ||barbershop mirrors || ||Place objects between parallel mirrors and view them over one of the mirrors. ||
||6A10.50 ||full view mirror || || ||
||6A10.50 ||height of a mirror for full view || ||Shades are pulled up from the bottom and down from the top covering a mirror until a person can just see their entire height. ||
||6A10.51 ||large plane mirror || ||A three foot plane mirror is used to show all of a six foot person. ||
||6A10.60 ||candle in a glass of water || ||A candle in front of a plate glass forms an image in a glass of water behind. ||
||6A10.60 ||plane mirror || ||A candle is placed in front of a sheet of glass and a beaker of water an equal distance behind. Place the entire apparatus on a rotating table. ||
||6A10.60 ||location of image || ||Place a sheet of glass between a burning candle and a glass of water so the image of the candle appears in the glass. ||
||6A10.65 ||half silvered mirror box || || ||
||6A10.65 ||Mirror Box || ||Two people look into opposite ends of a box containing a half silvered mirror in the center. As the light on one end is dimmed, the light on the other brightens, causing metamorphosis. ||
||6A10.76 ||sawblade optics || ||Keep the sawblade perpendicular by lining up the reflection of the board in the sawblade. ||
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||<10% style="text-align:center">'''PIRA #''' ||<style="text-align:center">'''Demonstration Name''' ||<60% style="text-align:center">'''Abstract''' ||
||6A20.10 ||blackboard optics - concave mirror ||Blackboard optics - concave mirror. ||
||6A20.10 ||blackboard optics - convex mirror ||Blackboard optics - convex mirror. ||
||6A20.10 ||concave and convex mirrors ||Shine parallel beams at convex and concave mirrors. Use a thread screen for display. ||
||6A20.11 ||optical disc with curved mirrors ||Use the optical disc with multiple beams and curved lens elements. ||
||6A20.11 ||optical disc - curved mirror ||Mount either concave or convex mirrors in the optical disc. ||
||6A20.11 ||large optical disc ||A large translucent screen and large lens elements scale up the Hartl optical disc. Diagrams. ||
||6A20.15 ||parallel lasers and curved mirrors ||Shine parallel lasers at converging and diverging mirrors and use chalk dust to make the beams visible. ||
||6A20.20 ||spherical abberation in a mirror ||Shine parallel rays at spherical and parabolic mirror elements, noting the difference in aberration. ||
||6A20.21 ||off focal point source ||A picture of the caustic formed by parallel laser rays incident on a parabolic mirror at 30 degrees. ||
||6A20.24 ||concave mirrors - caustics ||Directions for making a large cylindrical or parabolic mirror element. ||
||6A20.26 ||variable curved mirrors ||Aluminized mylar stretched over a coffee can makes a variable positive or negative mirror when the can is pressurized or evacuated. ||
||6A20.27 ||elliptical tank ||A filament lamp is placed at one focus of an elliptically shaped wall of shiny aluminum and chalk dust shows the image at the other focus. ||
||6A20.28 ||ellipsoidal mirror ||Compare the light intensity from the lamps at the near and far focus of an ellipsoidal mirror. Directions for making the mirror element. Diagram. ||
||6A20.30 ||flower in a vase ||A hidden flower at the center of curvature of a parabolic mirror appears in an empty vase. ||
||6A20.30 ||lamp in the socket ||A 40 W lamp is projected onto an empty socket. ||
||6A20.30 ||mirror and rose ||Hints for projecting a real image (rose) on an object (vase). ||
||6A20.31 ||cold candle ||Hold your finger in the inverted image of a candle burning at the center of curvature of a parabolic mirror. ||
||6A20.31 ||large concave mirror ||Hold a candle and other objects at the center of curvature of a large convex mirror. ||
||6A20.35 ||optic mirage ||Same as Oc-7. ||
||6A20.35 ||optic mirage ||Derivation of additional "magic separations" of the Optic Mirage that give images. ||
||6A20.35 ||optic mirage ||Two concave mirrors face each other. Images of objects resting on the bottom mirror appear at the center hole of the top mirror. ||
||6A20.36 ||shine an light on the Optic Mirage ||Shine a light on an shiny object in the Optic Mirage and the reflections will look real. ||
||6A20.37 ||red ball in hemisphere ||Looking at a red ball pendulum suspended from the rim of a hemispherical concave mirror makes one puke. ||
||6A20.37 ||swinging lamp and concave mirror ||A lamp pendulum is swung between the center of curvature and the principle focus on a concave mirror. ||
||6A20.40 ||projected arrow with mirror ||A converging mirror is used to project an image of an illuminated arrow onto a screen. ||
||6A20.40 ||image with a concave mirror ||A concave mirror is used to image a lamp filament on a screen or the wall. ||
||6A20.41 ||projected filament with mirror ||A converging mirror is used to project the image of a light bulb filament onto a screen. Masks can be used to stop down the mirror. ||
||6A20.42 ||rotating liquid mirror ||Rotate a pan of glycerine mixed with dark dye, using a lighted object as a source and ground glass screen or TV camera as a detector. ||
||6A20.45 ||no image with convex mirror ||Try to project the image of a filament from a convex mirror. ||
||6A20.45 ||convex and concave mirrors ||Large 16" convex and concave mirrors are shown. ||
||6A20.45 ||concave and convex mirror ||Project a lamp image with a concave mirror, then try convex. ||
||6A20.50 ||amusement park mirrors ||Cylindrical mirrors are made with ten inch radius of curvature. ||
||6A20.51 ||convex mirror ||View the image of your nose in a 1/2" diameter steel ball through a short focal length lens. ||
||6A20.60 ||lighting a cigarette ||Light a cigarette at the focal point of a parabolic mirror concentrating the beam of an arc light. ||
||6A20.60 ||energy at a focal point ||Remove the projection head of an overhead projector and hold a piece of paper at the focal point until it bursts into flame. ||
||<10% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''PIRA #''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Demonstration Name''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Subsets''' ||<60% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''Abstract''' ||
||6A20.10 ||blackboard optics - concave mirror || ||Blackboard optics - concave mirror. ||
||6A20.10 ||blackboard optics - convex mirror || ||Blackboard optics - convex mirror. ||
||6A20.10 ||concave and convex mirrors ||pira200 ||Shine parallel beams at convex and concave mirrors. Use a thread screen for display. ||
||6A20.11 ||optical disc with curved mirrors || ||Use the optical disc with multiple beams and curved lens elements. ||
||6A20.11 ||optical disc - curved mirror || ||Mount either concave or convex mirrors in the optical disc. ||
||6A20.11 ||large optical disc || ||A large translucent screen and large lens elements scale up the Hartl optical disc. Diagrams. ||
||6A20.15 ||parallel lasers and curved mirrors || ||Shine parallel lasers at converging and diverging mirrors and use chalk dust to make the beams visible. ||
||6A20.20 ||spherical abberation in a mirror || ||Shine parallel rays at spherical and parabolic mirror elements, noting the difference in aberration. ||
||6A20.21 ||off focal point source || ||A picture of the caustic formed by parallel laser rays incident on a parabolic mirror at 30 degrees. ||
||6A20.24 ||concave mirrors - caustics || ||Directions for making a large cylindrical or parabolic mirror element. ||
||6A20.26 ||variable curved mirrors || ||Aluminized mylar stretched over a coffee can makes a variable positive or negative mirror when the can is pressurized or evacuated. ||
||6A20.27 ||elliptical tank || ||A filament lamp is placed at one focus of an elliptically shaped wall of shiny aluminum and chalk dust shows the image at the other focus. ||
||6A20.28 ||ellipsoidal mirror || ||Compare the light intensity from the lamps at the near and far focus of an ellipsoidal mirror. Directions for making the mirror element. Diagram. ||
||6A20.30 ||flower in a vase || ||A hidden flower at the center of curvature of a parabolic mirror appears in an empty vase. ||
||6A20.30 ||lamp in the socket || ||A 40 W lamp is projected onto an empty socket. ||
||6A20.30 ||mirror and rose || ||Hints for projecting a real image (rose) on an object (vase). ||
||6A20.31 ||cold candle || ||Hold your finger in the inverted image of a candle burning at the center of curvature of a parabolic mirror. ||
||6A20.31 ||large concave mirror || ||Hold a candle and other objects at the center of curvature of a large convex mirror. ||
||6A20.35 ||optic mirage || ||Same as Oc-7. ||
||6A20.35 ||optic mirage || ||Derivation of additional "magic separations" of the Optic Mirage that give images. ||
||6A20.35 ||optic mirage || ||Two concave mirrors face each other. Images of objects resting on the bottom mirror appear at the center hole of the top mirror. ||
||6A20.36 ||shine an light on the Optic Mirage || ||Shine a light on an shiny object in the Optic Mirage and the reflections will look real. ||
||6A20.37 ||red ball in hemisphere || ||Looking at a red ball pendulum suspended from the rim of a hemispherical concave mirror makes one puke. ||
||6A20.37 ||swinging lamp and concave mirror || ||A lamp pendulum is swung between the center of curvature and the principle focus on a concave mirror. ||
||6A20.40 ||projected arrow with mirror || ||A converging mirror is used to project an image of an illuminated arrow onto a screen. ||
||6A20.40 ||image with a concave mirror || ||A concave mirror is used to image a lamp filament on a screen or the wall. ||
||6A20.41 ||projected filament with mirror || ||A converging mirror is used to project the image of a light bulb filament onto a screen. Masks can be used to stop down the mirror. ||
||6A20.42 ||rotating liquid mirror || ||Rotate a pan of glycerine mixed with dark dye, using a lighted object as a source and ground glass screen or TV camera as a detector. ||
||6A20.45 ||no image with convex mirror || ||Try to project the image of a filament from a convex mirror. ||
||6A20.45 ||convex and concave mirrors || ||Large 16" convex and concave mirrors are shown. ||
||6A20.45 ||concave and convex mirror || ||Project a lamp image with a concave mirror, then try convex. ||
||6A20.50 ||amusement park mirrors || ||Cylindrical mirrors are made with ten inch radius of curvature. ||
||6A20.51 ||convex mirror || ||View the image of your nose in a 1/2" diameter steel ball through a short focal length lens. ||
||6A20.60 ||lighting a cigarette || ||Light a cigarette at the focal point of a parabolic mirror concentrating the beam of an arc light. ||
||6A20.60 ||energy at a focal point || ||Remove the projection head of an overhead projector and hold a piece of paper at the focal point until it bursts into flame. ||
Line 139: Line 139:
||<10% style="text-align:center">'''PIRA #''' ||<style="text-align:center">'''Demonstration Name''' ||<60% style="text-align:center">'''Abstract''' ||
||6A40.10 ||apparent depth with tv camera ||Focus a camera on a spot and then note how far the camera is moved to refocus when a clear plastic block is placed on the spot. ||
||6A40.11 ||apparent depth ||Look down into a tall graduate and estimate the distance to a coin at the bottom. ||
||6A40.12 ||focusing telescope method ||Move a telescope back and forth on a optical bench to focus on the front and then on the back of a block of plexiglass or container of liquid. ||
||6A40.13 ||microwave index of refraction ||Index of refraction is determined by measuring the distance between minima with a movable plane mirror in a container of liquid. Diagram. ||
||6A40.15 ||refractive index of ice ||Freeze water by pumping in a hollow acrylic prism and measure the minimum deviation. ||
||6A40.20 ||Michelson index of refraction ||Place a gas cell in one leg of the Michelson interferometer and evacuate air or let in a gas while counting fringes. ||
||6A40.20 ||Michelson index of refraction ||Count fringes of laser light as air is let into an evacuated chamber in one leg of a Michelson interferometer. ||
||6A40.20 ||Michelson index of refraction ||A vacuum chamber is put in one leg of a Michelson interferometer and fringes are counted as air or a gas is leaked into the chamber. Reference: TPT 6(4),176. ||
||6A40.21 ||Raleigh refractometer ||Improvements on the Raleigh refractometer to make the fringes more visible for easier counting as the air is let back in to the tube. ||
||6A40.25 ||index of refraction of He and SF6 ||In addition to letting air (21 fringes) into one arm of the Michelson interferometer, let in He (3 fringes) and SF6 (55 fringes). ||
||6A40.30 ||Cheshire cat || ||
||6A40.30 ||disappearing eye dropper ||Place an eyedropper in a liquid with an index of refraction matched to the glass. ||
||6A40.31 ||more Christiansen filters ||A table of Christiansen filter pairs. See AJP 25,440 (1957) ||
||6A40.31 ||Christiansen filters ||A mixture of crushed glass and a liquid with the same index of refraction as glass is warmed in a container and exhibits colors. Directions for making a permanent display. Reference. ||
||6A40.36 ||grating pattern shift ||Shine a laser beam through a grating so the beam splits the air/liquid interface and measure the difference in the diffraction pattern for the light passing through the air and liquid. ||
||6A40.36 ||grating in aquarium ||Mount a transmission grating inside an aquarium and measure the diffracted laser beam on the other end with and without water in the tank. ||
||6A40.37 ||refraction with shadow and cube ||A shadow projected through a glass cube has a different length than normal. ||
||6A40.38 ||refractive index of beer ||The ratio of the apparent diameter to the actual diameter of a stick of pepperoni in a glass of beer gives the index of refraction. In the classroom, use a mesh projected on the wall and measure offset of a vertical wire. ||
||6A40.39 ||Abbe refractometer ||A liquid separates the hypotenuses of two right angle prisms. ||
||6A40.40 ||variable index of refraction tank ||Shine a laser beam through an aquarium with an unstirred sugar solution. ||
||6A40.40 ||variable index of refraction tank ||How to make a tank with varying concentrations of benzol and CS2. ||
||6A40.42 ||gradient index lens ||A small gradient index lens is passed around the class. It looks like a glass rod but one sees an inverted image when looking along the axis. ||
||6A40.45 ||mirage ||How to heat a long plate to demonstrate the mirage effect. ||
||6A40.46 ||mirage ||The image from a slide projector is directed just above a brass plate heated with a burner. ||
||6A40.47 ||mirage with a laser ||A laser beam almost grazing a hot plate will show deflection when the hot plate is turned on. ||
||6A40.47 ||laser beam deflection - thermal grad ||An apparatus for cooling a plate to deflect a laser beam downward. ||
||6A40.47 ||mirage with laser ||A laser beam is imaged through a keyhole and the beam then passes through a 1 meter oven. ||
||6A40.47 ||superior "superior" image ||A laser beam passing through a tank of water begins to deflect immediately when heat lamps are turned on. Images are also observed. ||
||6A40.48 ||not a mirage with a laser ||I haven't figured this out and have to go home to eat, so maybe some other time. ||
||6A40.49 ||mirage explaination note ||A note correcting misleading textbook explanations of the mirage. ||
||6A40.50 ||oil, water, laser || ||
||6A40.60 ||Schlieren image || ||
||6A40.60 ||cheap Schlieren ||A small, compact, portable, and inexpensive Schlieren instrument using an ordinary lamp and a light source. ||
||6A40.60 ||Schlieren, etc. ||Show and compare Schlieren, direct shadow, and interferometeric method of detecting small changes in the index of refraction of air. Diagrams, Details in appendix, p. 1352. ||
||6A40.61 ||Schlieren image of a candle ||A simple arrangement with a point source, lens, and candle near the lens, aperture, and screen for lecture demonstration purposes. ||
||6A40.61 ||Schlieren image of a candle ||Laser light is used in Schlieren projection of a candle flame. ||
||6A40.62 ||single mirror Schlieren system ||Two Ronchi rulings are placed at the radius of curvature of a spherical mirror. ||
||6A40.63 ||Schmidt-Cassegrain schlieren ||Two Schmidt-Cassegraion telescopes are used to make a simple inline Schlieren system. ||
||6A40.65 ||Toepler Schlieren apparatus ||A simpler Schlieren setup with colors indicating amount of deviation. ||
||6A40.67 ||refraction by gases ||Shadow project the Bunsen burner (H-137), hold a hot object in one arm on the Michelson interferometer. ||
||6A40.70 ||short beer || ||
||6A40.70 ||tall beer ||Properly designed glassware makes the beer look taller. ||
||6A40.70 ||cylindrical lens and short beers ||Analysis of the apparent inner diameter thick cylinder of a liquid of different index of refraction. ||
||6A40.70 ||short beers ||Paint the inside of the illusion cylinder, (AJP 43(8),741). ||
||6A40.70 ||beer mugs ||Two beer mugs were found that have the same outer dimensions and both appear to hold the same amount of beer when full, but actually differ in volume by a factor of two. ||
||6A40.70 ||short beer comment ||Easy explanation. ||
||6A40.90 ||plasma laser-beam focusing ||An expanded laser beam grazing a flat combustion flame from paint stripper is focused into a line. A second perpendicular flame gives a point. ||
||<10% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''PIRA #''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Demonstration Name''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Subsets''' ||<60% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''Abstract''' ||
||6A40.10 ||apparent depth with tv camera || ||Focus a camera on a spot and then note how far the camera is moved to refocus when a clear plastic block is placed on the spot. ||
||6A40.11 ||apparent depth || ||Look down into a tall graduate and estimate the distance to a coin at the bottom. ||
||6A40.12 ||focusing telescope method || ||Move a telescope back and forth on a optical bench to focus on the front and then on the back of a block of plexiglass or container of liquid. ||
||6A40.13 ||microwave index of refraction || ||Index of refraction is determined by measuring the distance between minima with a movable plane mirror in a container of liquid. Diagram. ||
||6A40.15 ||refractive index of ice || ||Freeze water by pumping in a hollow acrylic prism and measure the minimum deviation. ||
||6A40.20 ||Michelson index of refraction || ||Place a gas cell in one leg of the Michelson interferometer and evacuate air or let in a gas while counting fringes. ||
||6A40.20 ||Michelson index of refraction || ||Count fringes of laser light as air is let into an evacuated chamber in one leg of a Michelson interferometer. ||
||6A40.20 ||Michelson index of refraction || ||A vacuum chamber is put in one leg of a Michelson interferometer and fringes are counted as air or a gas is leaked into the chamber. Reference: TPT 6(4),176. ||
||6A40.21 ||Raleigh refractometer || ||Improvements on the Raleigh refractometer to make the fringes more visible for easier counting as the air is let back in to the tube. ||
||6A40.25 ||index of refraction of He and SF6 || ||In addition to letting air (21 fringes) into one arm of the Michelson interferometer, let in He (3 fringes) and SF6 (55 fringes). ||
||6A40.30 ||Cheshire cat || || ||
||6A40.30 ||disappearing beaker ||pira200 ||Place a small beaker in a liquid with an index of refraction matched to the glass (johnsons baby oil or wesson oil). ||
||6A40.31 ||more Christiansen filters || ||A table of Christiansen filter pairs. See AJP 25,440 (1957) ||
||6A40.31 ||Christiansen filters || ||A mixture of crushed glass and a liquid with the same index of refraction as glass is warmed in a container and exhibits colors. Directions for making a permanent display. Reference. ||
||6A40.36 ||grating pattern shift || ||Shine a laser beam through a grating so the beam splits the air/liquid interface and measure the difference in the diffraction pattern for the light passing through the air and liquid. ||
||6A40.36 ||grating in aquarium || ||Mount a transmission grating inside an aquarium and measure the diffracted laser beam on the other end with and without water in the tank. ||
||6A40.37 ||refraction with shadow and cube || ||A shadow projected through a glass cube has a different length than normal. ||
||6A40.38 ||refractive index of beer || ||The ratio of the apparent diameter to the actual diameter of a stick of pepperoni in a glass of beer gives the index of refraction. In the classroom, use a mesh projected on the wall and measure offset of a vertical wire. ||
||6A40.39 ||Abbe refractometer || ||A liquid separates the hypotenuses of two right angle prisms. ||
||6A40.40 ||variable index of refraction tank || ||Shine a laser beam through an aquarium with an unstirred sugar solution. ||
||6A40.40 ||variable index of refraction tank || ||How to make a tank with varying concentrations of benzol and CS2. ||
||6A40.42 ||gradient index lens || ||A small gradient index lens is passed around the class. It looks like a glass rod but one sees an inverted image when looking along the axis. ||
||6A40.45 ||mirage || ||How to heat a long plate to demonstrate the mirage effect. ||
||6A40.46 ||mirage || ||The image from a slide projector is directed just above a brass plate heated with a burner. ||
||6A40.47 ||mirage with a laser || ||A laser beam almost grazing a hot plate will show deflection when the hot plate is turned on. ||
||6A40.47 ||laser beam deflection - thermal grad || ||An apparatus for cooling a plate to deflect a laser beam downward. ||
||6A40.47 ||mirage with laser || ||A laser beam is imaged through a keyhole and the beam then passes through a 1 meter oven. ||
||6A40.47 ||superior "superior" image || ||A laser beam passing through a tank of water begins to deflect immediately when heat lamps are turned on. Images are also observed. ||
||6A40.48 ||not a mirage with a laser || ||I haven't figured this out and have to go home to eat, so maybe some other time. ||
||6A40.49 ||mirage explaination note || ||A note correcting misleading textbook explanations of the mirage. ||
||6A40.50 ||oil, water, laser || || ||
||6A40.60 ||Schlieren image || || ||
||6A40.60 ||cheap Schlieren || ||A small, compact, portable, and inexpensive Schlieren instrument using an ordinary lamp and a light source. ||
||6A40.60 ||Schlieren, etc. || ||Show and compare Schlieren, direct shadow, and interferometeric method of detecting small changes in the index of refraction of air. Diagrams, Details in appendix, p. 1352. ||
||6A40.61 ||Schlieren image of a candle || ||A simple arrangement with a point source, lens, and candle near the lens, aperture, and screen for lecture demonstration purposes. ||
||6A40.61 ||Schlieren image of a candle || ||Laser light is used in Schlieren projection of a candle flame. ||
||6A40.62 ||single mirror Schlieren system || ||Two Ronchi rulings are placed at the radius of curvature of a spherical mirror. ||
||6A40.63 ||Schmidt-Cassegrain schlieren || ||Two Schmidt-Cassegraion telescopes are used to make a simple inline Schlieren system. ||
||6A40.65 ||Toepler Schlieren apparatus || ||A simpler Schlieren setup with colors indicating amount of deviation. ||
||6A40.67 ||refraction by gases || ||Shadow project the Bunsen burner (H-137), hold a hot object in one arm on the Michelson interferometer. ||
||6A40.70 ||short beer || || ||
||6A40.70 ||tall beer || ||Properly designed glassware makes the beer look taller. ||
||6A40.70 ||cylindrical lens and short beers || ||Analysis of the apparent inner diameter thick cylinder of a liquid of different index of refraction. ||
||6A40.70 ||short beers || ||Paint the inside of the illusion cylinder, (AJP 43(8),741). ||
||6A40.70 ||beer mugs || ||Two beer mugs were found that have the same outer dimensions and both appear to hold the same amount of beer when full, but actually differ in volume by a factor of two. ||
||6A40.70 ||short beer comment || ||Easy explanation. ||
||6A40.90 ||plasma laser-beam focusing || ||An expanded laser beam grazing a flat combustion flame from paint stripper is focused into a line. A second perpendicular flame gives a point. ||
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||<10% style="text-align:center">'''PIRA #''' ||<style="text-align:center">'''Demonstration Name''' ||<60% style="text-align:center">'''Abstract''' ||
||6A42.10 ||blackboard optics - refraction ||Blackboard optics with a single beam and a large rectangle and prism of plexiglass. ||
||6A42.11 ||optical disk with glass block ||A single beam of light on the optical disc is used to show refraction through a rectangular block of glass. ||
||6A42.12 ||refraction/reflection from plastic ||Rotate a rectangle of plastic in a single beam of light. ||
||6A42.15 ||optical disc - semicircle ||A single beam of light is refracted at the flat but not the curved side if it leaves along a radius. ||
||6A42.20 ||refraction tank ||Rotate a beam of light in a tank of water containing some fluorescein. ||
||6A42.20 ||refraction tank ||A rotatable beam of light in a tank of water containing some fluorescein. ||
||6A42.21 ||Nakamara refraction tank || ||
||6A42.22 ||big plastic refraction tank || ||
||6A42.24 ||force table refeaction tank ||A small refraction tank is mounted on a force table. ||
||6A42.2
7 ||refraction ||Three refraction demos - optical tank, ripple tank, glass block. ||
||6A42.30 ||refraction model - rolling || ||
||6A42.30 ||refraction model ||An axle with independent 1" wheels rolls down an incline with one wheel on cloth, the other on the plain board. ||
||6A42.31 ||string models of refraction ||String models of refraction representing a water tank, prism, thin lens, comma aberration, and astigmatism are shown. Pictures, Construction details in appendix, p.1345. ||
||6A42.32 ||wavefront strips model || ||
||6A42.35 ||ripple tank refraction || ||
||6A42.40 ||penny in a cup || ||
||6A42.40 ||seeing a coin ||Pour water into a beaker until a coin at the bottom previously hidden by the side is visible. ||
||6A42.43 ||light in a tank || ||
||6A42.43 ||small refraction tank ||Position a lamp in an opaque tank so the filament cannot be seen, then add water until the light from the filament is seen over the edge of the tank. ||
||6A42.45 ||stick in the water || ||
||6A42.45 ||stick in water ||A stick appears bent when inserted into water at an angle. ||
||6A42.46 ||rugged refraction demonstration ||Cast a stick in a tumbler filled with clear casting resin. Pass around the class. ||
||6A42.47 ||acrylic/lead glass refraction ||Hold a stick behind stacked lead glass and acrylic blocks. The image of the stick is shifted when viewed off the normal to the surface of the blocks. ||
||6A42.50 ||minimum deviation of a prism ||At minimum deviation light reflected off the base is parallel to that passing through an equilateral prism. ||
||6A42.50 ||minimum angle of deviation ||Project a line filament through a large prism on a rotating platform with and without monochromatic filters. Reference: TPT 7(9),513. ||
||6A42.51 ||three prism stack || ||
||6A42.51 ||three different prisms ||A stack of three prisms of different glass shows different refraction and dispersion. ||
||6A42.55 ||paraffin prism and microwaves || ||
||6A42.55 ||microwave paraffin prism ||Determine the index of refraction of a large paraffin prism with 3.37 cm microwaves. ||
||6A42.60 ||dispersion in different media ||A multiple element prism is made with layers of different plastic and glass. ||
||6A42.65 ||dispersion of liquids ||A hollow prism is filled with a layer of carbon disulfide and a layer of water. ||
|| || || ||
||<10% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''PIRA #''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Demonstration Name''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Subsets''' ||<60% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''Abstract''' ||
||6A42.10 ||blackboard optics - refraction || ||Blackboard optics with a single beam and a large rectangle and prism of plexiglass. ||
||6A42.11 ||optical disk with glass block || ||A single beam of light on the optical disc is used to show refraction through a rectangular block of glass. ||
||6A42.12 ||refraction/reflection from plastic || ||Rotate a rectangle of plastic in a single beam of light. ||
||6A42.15 ||optical disc - semicircle || ||A single beam of light is refracted at the flat but not the curved side if it leaves along a radius. ||
||6A42.20 ||Big plastic refraction tank ||pira200 ||The light source can be rotated through 270 degreew to show refraction and total internal reflection for both air/platic and plastic/air interfaces. ||
||6A42.20 ||refraction
tank || ||A rotatable beam of light in a tank of water containing some fluorescein. ||
||6A42.21 ||Nakamara refraction tank || || ||
||6A42.22 ||
big plastic refraction tank || || ||
||6A42.24 ||force ta
ble refeaction tank || ||A small refraction tank is mounted on a force table. ||
||6A42.27 ||refraction || ||Three refraction demos - optical tank, ripple tank, glass block. ||
||6A42.30 ||refraction model - rolling || || ||
||6A42.30 ||refraction model || ||An axle with independent 1" wheels rolls down an incline with one wheel on cloth, the other on the plain board. ||
||6A42.31 ||string models of refraction || ||String models of refraction representing a water tank, prism, thin lens, comma aberration, and astigmatism are shown. Pictures, Construction details in appendix, p.1345. ||
||6A42.32 ||wavefront strips model || || ||
||6A42.35 ||ripple tank refraction || || ||
||6A42.40 ||penny in a cup || || ||
||6A42.40 ||seeing a coin || ||Pour water into a beaker until a coin at the bottom previously hidden by the side is visible. ||
||6A42.43 ||light in a tank || || ||
||6A42.43 ||small refraction tank || ||Position a lamp in an opaque tank so the filament cannot be seen, then add water until the light from the filament is seen over the edge of the tank. ||
||6A42.45 ||stick in the water || || ||
||6A42.45 ||stick in water || ||A stick appears bent when inserted into water at an angle. ||
||6A42.46 ||rugged refraction demonstration || ||Cast a stick in a tumbler filled with clear casting resin. Pass around the class. ||
||6A42.47 ||acrylic/lead glass refraction || ||Hold a stick behind stacked lead glass and acrylic blocks. The image of the stick is shifted when viewed off the normal to the surface of the blocks. ||
||6A42.50 ||minimum deviation of a prism || ||At minimum deviation light reflected off the base is parallel to that passing through an equilateral prism. ||
||6A42.50 ||minimum angle of deviation || ||Project a line filament through a large prism on a rotating platform with and without monochromatic filters. Reference: TPT 7(9),513. ||
||6A42.51 ||three prism stack || || ||
||6A42.51 ||three different prisms || ||A stack of three prisms of different glass shows different refraction and dispersion. ||
||6A42.55 ||paraffin prism and microwaves || || ||
||6A42.55 ||microwave paraffin prism || ||Determine the index of refraction of a large paraffin prism with 3.37 cm microwaves. ||
||6A42.60 ||dispersion in different media || ||A multiple element prism is made with layers of different plastic and glass. ||
||6A42.65 ||dispersion of liquids || ||A hollow prism is filled with a layer of carbon disulfide and a layer of water. ||
|| || || || ||
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||<10% style="text-align:center">'''PIRA #''' ||<style="text-align:center">'''Demonstration Name''' ||<60% style="text-align:center">'''Abstract''' ||
||6A44.10 ||blackboard optics ||Multiple beams of light pass through large scale optical elements. ||
||6A44.11 ||optical disk with prism, semicircle ||A single beam of light on the optical disk shows total internal reflection when passed through a prism. ||
||6A44.11 ||semicircular element on disc ||A beam of light entering a semicircular glass disc normal to the curved surface is reflected off the flat side. ||
||6A44.20 ||critical angle in refraction tank ||A beam in a tank of water is rotated until there is total internal reflection at the surface. ||
||6A44.20 ||refraction tank ||Adjust the path of a beam with mirrors in a tank of water with fluorescein. to show total internal reflection. ||
||6A44.20 ||critical angle/ total internal refle ||Shine a beam through the side of a tank containing fluorescein. Rotate a mirror in the tank so the beam passes through the critical angle. ||
||6A44.22 ||big plastic refraction tank || ||
||6A44.25 ||Snell's wheel || ||
||6A44.30 ||ripple tank total reflection ||Vary the angle of incidence of ripple tank waves to a boundary with water depths of 13 and 3 mm. ||
||6A44.35 ||frust. tot. int. ref. ||see 7A50.12 ||
||6A44.40 ||laser and fiber optics ||Shine a laser into a curved plastic rod. ||
||6A44.40 ||laser and fiber optics ||A laser is used with a bundle of fiber optics, a curled plexiglass rod, and a 1" square lean rod. ||
||6A44.40 ||light pipe ||Light is projected down a clear plexiglass spiral. ||
||6A44.40 ||curved glass tube ||Shine a bright light source through a curved glass tube. ||
||6A44.40 ||[[LightPipeUlexite|light pipes]] ||Several light pipes and fiber optics are shown. ||
||6A44.40 ||light pipes ||Shine a laser into a curved plastic rod. ||
||6A44.41 ||optical path in fibers ||Shine a laser down a bent rectangular bar. ||
||6A44.42 ||steal the signal || ||
||6A44.43 ||bounce around a tube ||A laser beam bounces around a thick walled plexiglass tube due to total internal reflection. ||
||6A44.45 ||water stream light pipe ||Shine a laser beam down the water stream issuing from the orifice of a plexiglass tank of water. ||
||6A44.45 ||illuminated fountain ||Shine a light down a stream of water. ||
||6A44.45 ||laser waterfall ||Shine a laser down the center of a nozzle and it follows the water stream. ||
||6A44.50 ||light below surface ||An underwater light illuminates powder on the surface of water to form a central spot of light. ||
||6A44.50 ||ring of light ||Same as Oe-2. ||
||6A44.50 ||light below surface ||An underwater light illuminates powder on the surface of water to form a central spot of light. ||
||6A44.51 ||ring of light index of refraction ||Find the index of refraction of transparent plates by wetting a filter paper on one side, shining the laser in that side, and measuring the diameter of the light circle. ||
||6A44.52 ||ring of darkness ||Shine a laser through a sample to a white diffusely reflecting surface and measure the darkened circle on the top surface. ||
||6A44.53 ||water/benzol surface ||Total internal reflection from a water/benzol surface. ||
||6A44.54 ||hidden mercury in a test tube ||Mercury in a partially filled test tube cannot be seen from above when immersed in water. ||
||6A44.54 ||total internal and metallic reflect ||View a test tube half full of mercury half in water from an angle of 100 degrees to the incident beam. The glass-air interface is brighter. ||
||6A44.55 ||black ball turns silver ||A soot covered ball appears silver under water due to reflected light from air trapped on the surface of the ball. ||
||6A44.55 ||soot ball ||A ball covered with soot appears silvery in water due to the air trapped on the soot forming an air water interface. ||
||6A44.55 ||silver soot ball ||A ball coated with soot appears silver in water. ||
||6A44.56 ||glass-air interface ||Two thin strips of glass are sealed with an air barrier and immersed in water. Turned to the proper angle to the incident beam it will exhibit total internal reflection. ||
||6A44.56 ||near critical angle ||Use the entrapped air slide in a water bath or air between right angle prisms to show the colors of the transmitted and reflected light near the critical angle. Dispersing the two beams will show complementary spectra. ||
||6A44.59 ||add water to snow ||Project light through snow or chopped ice and add water. ||
||6A44.60 ||diamond ||A thin beam of light is directed on a diamond and the reflections are projected onto a cardboard. ||
||6A44.65 ||inversion with a right angle prism ||Project an image upside down and place a right angle prism in the beam to invert the image. ||
||6A44.65 ||right angle prism inverter ||A right angle prism placed in a projected beam inverts the image. ||
||6A44.66 ||right angle prism - double reflectio ||A beam entering the hypotenuse of a right angle prism is inverted and reversed. ||
||6A44.67 ||two right angle prisms - inversion ||Two right angle prisms are arranged to invert and pervert the image. ||
||6A44.68 ||prisms ||Several prisms demonstrate total internal reflection. ||
||6A44.70 ||Goos-Haenchen shift ||The sideways displacement of a beam at total internal reflection is shown with 3 cm microwaves. ||
||<10% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''PIRA #''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Demonstration Name''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Subsets''' ||<60% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''Abstract''' ||
||6A44.10 ||blackboard optics ||pira200 ||Multiple beams of light pass through large scale optical elements. ||
||6A44.11 ||optical disk with prism, semicircle || ||A single beam of light on the optical disk shows total internal reflection when passed through a prism. ||
||6A44.11 ||semicircular element on disc || ||A beam of light entering a semicircular glass disc normal to the curved surface is reflected off the flat side. ||
||6A44.20 ||critical angle in refraction tank || ||A beam in a tank of water is rotated until there is total internal reflection at the surface. ||
||6A44.20 ||refraction tank || ||Adjust the path of a beam with mirrors in a tank of water with fluorescein. to show total internal reflection. ||
||6A44.20 ||critical angle/ total internal refle || ||Shine a beam through the side of a tank containing fluorescein. Rotate a mirror in the tank so the beam passes through the critical angle. ||
||6A44.22 ||big plastic refraction tank || || ||
||6A44.25 ||Snell's wheel || || ||
||6A44.30 ||ripple tank total reflection || ||Vary the angle of incidence of ripple tank waves to a boundary with water depths of 13 and 3 mm. ||
||6A44.35 ||frust. tot. int. ref. || ||see 7A50.12 ||
||6A44.40 ||laser and fiber optics || ||Shine a laser into a curved plastic rod. ||
||6A44.40 ||laser and fiber optics || ||A laser is used with a bundle of fiber optics, a curled plexiglass rod, and a 1" square lean rod. ||
||6A44.40 ||light pipe || ||Light is projected down a clear plexiglass spiral. ||
||6A44.40 ||curved glass tube || ||Shine a bright light source through a curved glass tube. ||
||6A44.40 ||[[LightPipeUlexite|light pipes--Ulexite]] ||pira200 ||Several light pipes and fiber optics are shown. ||
||6A44.40 ||light pipes || ||Shine a laser into a curved plastic rod. ||
||6A44.41 ||optical path in fibers || ||Shine a laser down a bent rectangular bar. ||
||6A44.42 ||steal the signal || || ||
||6A44.43 ||bounce around a tube || ||A laser beam bounces around a thick walled plexiglass tube due to total internal reflection. ||
||6A44.45 ||water stream light pipe || ||Shine a laser beam down the water stream issuing from the orifice of a plexiglass tank of water. ||
||6A44.45 ||illuminated fountain || ||Shine a light down a stream of water. ||
||6A44.45 ||laser waterfall || ||Shine a laser down the center of a nozzle and it follows the water stream. ||
||6A44.50 ||light below surface || ||An underwater light illuminates powder on the surface of water to form a central spot of light. ||
||6A44.50 ||ring of light || ||Same as Oe-2. ||
||6A44.50 ||light below surface || ||An underwater light illuminates powder on the surface of water to form a central spot of light. ||
||6A44.51 ||ring of light index of refraction || ||Find the index of refraction of transparent plates by wetting a filter paper on one side, shining the laser in that side, and measuring the diameter of the light circle. ||
||6A44.52 ||ring of darkness || ||Shine a laser through a sample to a white diffusely reflecting surface and measure the darkened circle on the top surface. ||
||6A44.53 ||water/benzol surface || ||Total internal reflection from a water/benzol surface. ||
||6A44.54 ||hidden mercury in a test tube || ||Mercury in a partially filled test tube cannot be seen from above when immersed in water. ||
||6A44.54 ||total internal and metallic reflect || ||View a test tube half full of mercury half in water from an angle of 100 degrees to the incident beam. The glass-air interface is brighter. ||
||6A44.55 ||black ball turns silver || ||A soot covered ball appears silver under water due to reflected light from air trapped on the surface of the ball. ||
||6A44.55 ||soot ball || ||A ball covered with soot appears silvery in water due to the air trapped on the soot forming an air water interface. ||
||6A44.55 ||silver soot ball || ||A ball coated with soot appears silver in water. ||
||6A44.56 ||glass-air interface || ||Two thin strips of glass are sealed with an air barrier and immersed in water. Turned to the proper angle to the incident beam it will exhibit total internal reflection. ||
||6A44.56 ||near critical angle || ||Use the entrapped air slide in a water bath or air between right angle prisms to show the colors of the transmitted and reflected light near the critical angle. Dispersing the two beams will show complementary spectra. ||
||6A44.59 ||add water to snow || ||Project light through snow or chopped ice and add water. ||
||6A44.60 ||diamond || ||A thin beam of light is directed on a diamond and the reflections are projected onto a cardboard. ||
||6A44.65 ||inversion with a right angle prism || ||Project an image upside down and place a right angle prism in the beam to invert the image. ||
||6A44.65 ||right angle prism inverter || ||A right angle prism placed in a projected beam inverts the image. ||
||6A44.66 ||right angle prism - double reflectio || ||A beam entering the hypotenuse of a right angle prism is inverted and reversed. ||
||6A44.67 ||two right angle prisms - inversion || ||Two right angle prisms are arranged to invert and pervert the image. ||
||6A44.68 ||prisms || ||Several prisms demonstrate total internal reflection. ||
||6A44.70 ||Goos-Haenchen shift || ||The sideways displacement of a beam at total internal reflection is shown with 3 cm microwaves. ||
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||<10% style="text-align:center">'''PIRA #''' ||<style="text-align:center">'''Demonstration Name''' ||<60% style="text-align:center">'''Abstract''' ||
||6A46.10 ||rainbow ||An arc lamp directed at a sphere of water forms a rainbow on a screen. ||
||6A46.10 ||rainbow ||Project a beam through a spherical flask of water and view the rainbow on a screen placed between the light and the flask. ||
||6A46.11 ||artifical rainbow ||Form a vertical circle "rainbow" by placing a tube of water between a prism and screen. ||
||6A46.12 ||secondary rainbow ||Use a single sphere with the back surface coated with a reflecting material to show both primary and secondary bows with increased intensity. ||
||6A46.15 ||rainbow droplets ||Small droplets formed by spraying an atomizer on a soot covered glass plate glisten like colored jewels when viewed at 41 degrees. ||
||6A46.16 ||rainbow dust ||On using small glass spheres to generate bows and halos. ||
||6A46.20 ||rainbow model ||Depict a three dimensional model of the rainbow with strings representing light rays. ||
||6A46.25 ||rainbow ||A mechanical model for demonstrating rainbow formation shows why the rainbow is produced and why size depends on the time of day. ||
||6A46.26 ||rod and dowel raindrop model ||A rod and dowel raindrop model is used to show why a rainbow is bow-shaped. ||
||6A46.30 ||optical disc with spherical lens ||A single beam into a circular glass element is refracted, totally internally reflected, and refracted out again. ||
||6A46.30 ||rainbow disc ||A single beam is used with a spherical glass element on an optical board to show the path of refracted light that produces a rainbow. ||
||<10% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''PIRA #''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Demonstration Name''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Subsets''' ||<60% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''Abstract''' ||
||6A46.10 ||rainbow || ||An arc lamp directed at a sphere of water forms a rainbow on a screen. ||
||6A46.10 ||rainbow || ||Project a beam through a spherical flask of water and view the rainbow on a screen placed between the light and the flask. ||
||6A46.11 ||artifical rainbow || ||Form a vertical circle "rainbow" by placing a tube of water between a prism and screen. ||
||6A46.12 ||secondary rainbow || ||Use a single sphere with the back surface coated with a reflecting material to show both primary and secondary bows with increased intensity. ||
||6A46.15 ||rainbow droplets || ||Small droplets formed by spraying an atomizer on a soot covered glass plate glisten like colored jewels when viewed at 41 degrees. ||
||6A46.16 ||[[RainbowDust|rainbow dust]] || ||On using small glass spheres to generate bows and halos. ||
||6A46.20 ||rainbow model || ||Depict a three dimensional model of the rainbow with strings representing light rays. ||
||6A46.25 ||rainbow || ||A mechanical model for demonstrating rainbow formation shows why the rainbow is produced and why size depends on the time of day. ||
||6A46.26 ||rod and dowel raindrop model || ||A rod and dowel raindrop model is used to show why a rainbow is bow-shaped. ||
||6A46.30 ||optical disc with spherical lens || ||A single beam into a circular glass element is refracted, totally internally reflected, and refracted out again. ||
||6A46.30 ||rainbow disc || ||A single beam is used with a spherical glass element on an optical board to show the path of refracted light that produces a rainbow. ||
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||<10% style="text-align:center">'''PIRA #''' ||<style="text-align:center">'''Demonstration Name''' ||<60% style="text-align:center">'''Abstract''' ||
||6A60.10 ||blackboard optics - thin lens ||Blackboard optics are used with convex and concave thin lens elements. ||
||6A60.11 ||optical disk with thin lens ||The optical disk is used with multiple beams and a thin lens element. ||
||6A60.11 ||optical disc - lenses ||Various lens elements are used with the optical disc. ||
||6A60.12 ||optical disc - refraction at curved ||A long plastic slab with a concave surface at one end and a convex surface at the other is used in the optical disc. ||
||6A60.15 ||ripple tank convex lens || ||
||6A60.15 ||ripple tank - lens model ||Refraction due to depth differences over a lens shaped area in the ripple tank. ||
||6A60.16 ||ripple tank concave lens || ||
||6A60.20 ||parallel lasers and lenses ||Parallel lasers are passed through converging and diverging lenses. Chalk dust illuminates the beams. ||
||6A60.20 ||parallel lasers and lenses ||Parallel lasers are used with chalk dust to show the path of rays through a lens and combinations of lenses. ||
||6A60.20 ||ray tracing with lenses ||Show parallel rays passing through a lens element and converging. ||
||6A60.30 ||thin lens projection ||Project the filament of a lamp with a thin lens. ||
||6A60.30 ||projected filament with lens ||Project the filament of a light bulb on the wall. The lens can be stopped down. ||
||6A60.30 ||thin lens projection ||Project the filament of a lamp with a thin lens. ||
||6A60.30 ||real image formation ||With a source and screen at the ends of a long optical bench, show the two positions a lens will produce an image. ||
||6A60.31 ||projected arrow with lens ||Use an illuminated arrow with a converging lens to project an image on a screen. ||
||6A60.32 ||thin concave lens ||Try to project an image with a thin concave lens. ||
||6A60.33 ||image location ||A set of lenses for demonstration the six general cases for object and image distances. ||
||6A60.35 ||lens magnification ||Place various lenses between a backlit grid and the class. ||
||6A60.40 ||position of virtual image with TV ||Find the virtual image location by focusing on an object through a lens removing the lens, and moving the object to a focused position. Also the apparent depth with TV method. ||
||6A60.45 ||focal length of a lens - mirror ||When a lamp is at the focal length, the image is at the same place if a mirror is placed directly behind the lens. ||
||6A60.48 ||effect of medium on focal length ||Find the focal length of a lens, then find the focal length of the same lens in water. ||
||6A60.49 ||lenses ||All sorts of focal length stuff. ||
||6A60.50 ||pinholes projected with lens ||Pinholes are pricked in a black paper covering a long filament bulb. Bring the multiple images into one image with a converging lens. ||
||6A60.50 ||action of a lens ||Project the images of a filament through several pinholes and then add a lens to collect the many into a single image. ||
||6A60.60 ||paraffin lens and microwaves || ||
||6A60.60 ||microwave lens ||Construct a microwave lens and prisms of stacks of properly contoured aluminum sheets separated by just over one half the wavelength. ||
||<10% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''PIRA #''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Demonstration Name''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Subsets''' ||<60% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''Abstract''' ||
||6A60.10 ||blackboard optics - thin lens || ||Blackboard optics are used with convex and concave thin lens elements. ||
||6A60.11 ||optical disk with thin lens || ||The optical disk is used with multiple beams and a thin lens element. ||
||6A60.11 ||optical disc - lenses || ||Various lens elements are used with the optical disc. ||
||6A60.12 ||optical disc - refraction at curved || ||A long plastic slab with a concave surface at one end and a convex surface at the other is used in the optical disc. ||
||6A60.15 ||ripple tank convex lens || || ||
||6A60.15 ||ripple tank - lens model || ||Refraction due to depth differences over a lens shaped area in the ripple tank. ||
||6A60.16 ||ripple tank concave lens || || ||
||6A60.20 ||parallel lasers and lenses || ||Parallel lasers are passed through converging and diverging lenses. Chalk dust illuminates the beams. ||
||6A60.20 ||parallel lasers and lenses || ||Parallel lasers are used with chalk dust to show the path of rays through a lens and combinations of lenses. ||
||6A60.20 ||ray tracing with lenses || ||Show parallel rays passing through a lens element and converging. ||
||6A60.30 ||thin lens projection || ||Project the filament of a lamp with a thin lens. ||
||6A60.30 ||projected filament with lens ||pira200 ||Project the filament of a light bulb on the wall. The lens can be stopped down. ||
||6A60.30 ||thin lens projection || ||Project the filament of a lamp with a thin lens. ||
||6A60.30 ||real image formation || ||With a source and screen at the ends of a long optical bench, show the two positions a lens will produce an image. ||
||6A60.31 ||projected arrow with lens || ||Use an illuminated arrow with a converging lens to project an image on a screen. ||
||6A60.32 ||thin concave lens || ||Try to project an image with a thin concave lens. ||
||6A60.33 ||image location || ||A set of lenses for demonstration the six general cases for object and image distances. ||
||6A60.35 ||lens magnification || ||Place various lenses between a backlit grid and the class. ||
||6A60.40 ||position of virtual image with TV || ||Find the virtual image location by focusing on an object through a lens removing the lens, and moving the object to a focused position. Also the apparent depth with TV method. ||
||6A60.45 ||focal length of a lens - mirror || ||When a lamp is at the focal length, the image is at the same place if a mirror is placed directly behind the lens. ||
||6A60.48 ||effect of medium on focal length || ||Find the focal length of a lens, then find the focal length of the same lens in water. ||
||6A60.49 ||lenses || ||All sorts of focal length stuff. ||
||6A60.50 ||pinholes projected with lens || ||Pinholes are pricked in a black paper covering a long filament bulb. Bring the multiple images into one image with a converging lens. ||
||6A60.50 ||action of a lens || ||Project the images of a filament through several pinholes and then add a lens to collect the many into a single image. ||
||6A60.60 ||paraffin lens and microwaves || || ||
||6A60.60 ||microwave lens || ||Construct a microwave lens and prisms of stacks of properly contoured aluminum sheets separated by just over one half the wavelength. ||
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||<10% style="text-align:center">'''PIRA #''' ||<style="text-align:center">'''Demonstration Name''' ||<60% style="text-align:center">'''Abstract''' ||
||6A61.10 ||pinhole projection ||Place a lamp in a box covered with heavy paper and poke a hole in the paper with a wire 1-2 mm in diameter. Poke more holes for more images. Try different size holes. ||
||6A61.10 ||pinhole projection ||Interpose a metal plate with two holes between a lamp and a screen on an optical bench. ||
||6A61.15 ||pinholes projected/lens ||see 6A60.50 ||
||6A61.20 ||pinhole camera ||Place film at the back of a box with a hole. ||
||6A61.20 ||pinhole camera ||Project a lamp filament onto a screen. Vary the distance of the screen and the size of the pinhole. Includes animation. ||
||6A61.21 ||pinhole camera ||A sliding box with has pinhole at one end and a frosted glass at the other. Try a 1" diameter hole in the shutter of a window in a darkened room. Directions on making a pinhole camera. ||
||6A61.22 ||pinhole imagery ||A complete discussion of pinhole imagery. ||
||6A61.23 ||pinhole camera ||A small tube covered with tin foil with a small hole replaces the lens of a TV camera. ||
||6A61.30 ||fish-eye camera ||A pinhole camera filled with water or solid Lucite gives a fish-eye view. Diagram, Pictures. ||
||<10% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''PIRA #''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Demonstration Name''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Subsets''' ||<60% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''Abstract''' ||
||6A61.10 ||pinhole projection || ||Place a lamp in a box covered with heavy paper and poke a hole in the paper with a wire 1-2 mm in diameter. Poke more holes for more images. Try different size holes. ||
||6A61.10 ||pinhole projection || ||Interpose a metal plate with two holes between a lamp and a screen on an optical bench. ||
||6A61.15 ||pinholes projected/lens || ||see 6A60.50 ||
||6A61.20 ||pinhole camera || ||Place film at the back of a box with a hole. ||
||6A61.20 ||pinhole camera || ||Project a lamp filament onto a screen. Vary the distance of the screen and the size of the pinhole. Includes animation. ||
||6A61.21 ||pinhole camera || ||A sliding box with has pinhole at one end and a frosted glass at the other. Try a 1" diameter hole in the shutter of a window in a darkened room. Directions on making a pinhole camera. ||
||6A61.22 ||pinhole imagery || ||A complete discussion of pinhole imagery. ||
||6A61.23 ||pinhole camera || ||A small tube covered with tin foil with a small hole replaces the lens of a TV camera. ||
||6A61.30 ||fish-eye camera || ||A pinhole camera filled with water or solid Lucite gives a fish-eye view. Diagram, Pictures. ||
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||<10% style="text-align:center">'''PIRA #''' ||<style="text-align:center">'''Demonstration Name''' ||<60% style="text-align:center">'''Abstract''' ||
||6A65.09 ||computer assisted optics ||The authors describe a program that covers spherical and chromatic aberration in addition to other topics. BASIC, PC, available from authors. ||
||6A65.10 ||improving an image with a stop ||Use a stop to improve the image through a short focal length lens. ||
||6A65.11 ||depth of focus ||Use a six inch long glowing wire as an extended object for showing the effect of stopping down a lens. ||
||6A65.15 ||optical disc - circular glass plate ||Use a circular plate of glass with the optical disc as an example of a thick lens. ||
||6A65.20 ||chromatic aberration ||A diaphragm moved near the focus selects red or blue light from beams passing through the edge of a lens. ||
||6A65.21 ||aplanic properties of a sphere ||Aplanic systems show no spherical aberration or coma for some special position of object and image demonstrated here with a spherical lens. ||
||6A65.21 ||chromatic aberration ||Project spots of light on a screen from several points on a lens. Note chromatic aberration and then add a second correction lens. ||
||6A65.22 ||chromatic aberration ||Show the image formation distance for red and uv light using a fluorescent screen to display the uv. ||
||6A65.23 ||lens aberrations with a laser ||Good quality telescope and microscope objectives are used to show aberrations in optical systems. ||
||6A65.24 ||chromatic and spherical aberration ||Use diaphragms with central, annular, and other openings to show spherical and chromatic aberration. ||
||6A65.30 ||barrel and pincushion distortion ||Project an illuminated wire mesh with a large lens. Place a diaphragm between the lens and the mesh for barrel distortion and between the lens and the screen for pincushion distortion. ||
||6A65.31 ||off axis distortion ||Parallel rays of light pass through a lens element held off axis. ||
||6A65.34 ||astigmatism ||Focus light from a circular hole on a screen, then add a cylindrical lens. ||
||6A65.35 ||astigmatism and distortion ||An illuminated wire mesh is projected onto a screen with a short focal length condenser lens. Turn the lens about an axis parallel to either set of wires and the horizontal and vertical wires will focus at different points. ||
||6A65.40 ||spherical aberration ||Project an image with a spherical planoconvex lens. Stop the outer portion of the lens, then the center. ||
||6A65.45 ||abberation with a plano convex lens ||A series of parallel beams around the outside edge of a plano convex lens made visible with chalk dust are better focused when the light enters the curved side. ||
||6A65.46 ||spherical abberation and coma /laser ||Diagram and pictures of a setup to project lens aberrations with a laser. ||
||6A65.52 ||water lens ||A beam of light is directed through a round flask filled with water. ||
||6A65.52 ||fillable air lenses ||Convex and concave lenses are filled with water and air in water and air. ||
||6A65.53 ||spherical lens ||Compare a thermometer at the center of a water filled flask to one at the far side. Picture. ||
||6A65.54 ||wine bottle lens ||Fill a round flask with a wine bottle bottom with water and fluorescein to show diverging light. ||
||6A65.55 ||watch glass lens ||A vertical lens can be formed by pouring various liquids into a watch glass. ||
||6A65.56 ||CHOICE OXIDE ||CHOICE OXIDE GLASS LAMP is viewed through a tube filled with water. ||
||6A65.58 ||light beam strikes rod ||A light beam incident on the side of a glass rod at some angle will produce a cone with the half angle equal to the angle of incidence. ||
||6A65.60 ||plastic lenses ||The advantages of plastic lenses. ||
||6A65.70 ||Fresnel lens history ||An article on the discovery of stepped lenses. ||
||6A65.70 ||Fresnel lens ||Fresnel lens magnification. Animation showing construction of a Fresnel lens. ||
||<10% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''PIRA #''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Demonstration Name''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Subsets''' ||<60% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''Abstract''' ||
||6A65.09 ||computer assisted optics || ||The authors describe a program that covers spherical and chromatic aberration in addition to other topics. BASIC, PC, available from authors. ||
||6A65.10 ||improving an image with a stop || ||Use a stop to improve the image through a short focal length lens. ||
||6A65.11 ||depth of focus || ||Use a six inch long glowing wire as an extended object for showing the effect of stopping down a lens. ||
||6A65.15 ||optical disc - circular glass plate || ||Use a circular plate of glass with the optical disc as an example of a thick lens. ||
||6A65.20 ||chromatic aberration || ||A diaphragm moved near the focus selects red or blue light from beams passing through the edge of a lens. ||
||6A65.21 ||aplanic properties of a sphere || ||Aplanic systems show no spherical aberration or coma for some special position of object and image demonstrated here with a spherical lens. ||
||6A65.21 ||chromatic aberration || ||Project spots of light on a screen from several points on a lens. Note chromatic aberration and then add a second correction lens. ||
||6A65.22 ||chromatic aberration || ||Show the image formation distance for red and uv light using a fluorescent screen to display the uv. ||
||6A65.23 ||lens aberrations with a laser || ||Good quality telescope and microscope objectives are used to show aberrations in optical systems. ||
||6A65.24 ||chromatic and spherical aberration || ||Use diaphragms with central, annular, and other openings to show spherical and chromatic aberration. ||
||6A65.30 ||barrel and pincushion distortion || ||Project an illuminated wire mesh with a large lens. Place a diaphragm between the lens and the mesh for barrel distortion and between the lens and the screen for pincushion distortion. ||
||6A65.31 ||off axis distortion || ||Parallel rays of light pass through a lens element held off axis. ||
||6A65.34 ||astigmatism || ||Focus light from a circular hole on a screen, then add a cylindrical lens. ||
||6A65.35 ||astigmatism and distortion || ||An illuminated wire mesh is projected onto a screen with a short focal length condenser lens. Turn the lens about an axis parallel to either set of wires and the horizontal and vertical wires will focus at different points. ||
||6A65.40 ||spherical aberration || ||Project an image with a spherical planoconvex lens. Stop the outer portion of the lens, then the center. ||
||6A65.45 ||abberation with a plano convex lens || ||A series of parallel beams around the outside edge of a plano convex lens made visible with chalk dust are better focused when the light enters the curved side. ||
||6A65.46 ||spherical abberation and coma /laser || ||Diagram and pictures of a setup to project lens aberrations with a laser. ||
||6A65.52 ||water lens || ||A beam of light is directed through a round flask filled with water. ||
||6A65.52 ||fillable air lenses || ||Convex and concave lenses are filled with water and air in water and air. ||
||6A65.53 ||spherical lens || ||Compare a thermometer at the center of a water filled flask to one at the far side. Picture. ||
||6A65.54 ||wine bottle lens || ||Fill a round flask with a wine bottle bottom with water and fluorescein to show diverging light. ||
||6A65.55 ||watch glass lens || ||A vertical lens can be formed by pouring various liquids into a watch glass. ||
||6A65.56 ||CHOICE OXIDE || ||CHOICE OXIDE GLASS LAMP is viewed through a tube filled with water. ||
||6A65.58 ||light beam strikes rod || ||A light beam incident on the side of a glass rod at some angle will produce a cone with the half angle equal to the angle of incidence. ||
||6A65.60 ||plastic lenses || ||The advantages of plastic lenses. ||
||6A65.70 ||Fresnel lens history || ||An article on the discovery of stepped lenses. ||
||6A65.70 ||Fresnel lens || ||Fresnel lens magnification. Animation showing construction of a Fresnel lens. ||
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||<10% style="text-align:center">'''PIRA #''' ||<style="text-align:center">'''Demonstration Name''' ||<60% style="text-align:center">'''Abstract''' ||
||6A70.10 ||model microscope ||Make a demonstration microscope with a short focal length lens and reading glass. ||
||6A70.12 ||microscope chart ||A diagram on a wall chart shows the action of a microscope. ||
||6A70.13 ||fake microscope ||A mirror arrangement and fake microscope make normal objects seem miniaturized. ||
||6A70.14 ||primative microscope ||A Leeuwenhoek 100 X magnifier is made with a glass bead on the end of a tapered tube. ||
||6A70.20 ||telescope ||Set up astronomical, terrestrial, and Galilean telescopes for students to look through individually. ||
||6A70.21 ||real telescope ||Observe with a Questar telescope. ||
||6A70.22 ||sun telescope ||Make a heliostat for a room with a south facing window. Reference: AJP 38(3),391-2. ||
||6A70.23 ||large telescopes ||Large telescopes are available on the roof for observations. ||
||6A70.25 ||telephoto lens ||An illuminated wire mesh is projected on a screen using a telephoto lens setup. ||
||6A70.30 ||camera model || ||
||6A70.31 ||cameras ||Several cameras are exhibited. ||
||6A70.35 ||projector model || ||
||6A70.40 ||superposition of images ||A wire screen placed at the point where a real image is formed is projected through a second lens to form a combined image. ||
||6A70.45 ||lens combinations ||A projection lantern double lens system. ||
||6A70.50 ||measuring with moire fringes ||A long discussion on measuring with moire fringes. Diagrams, Construction details in appendix, p.1346. ||
||6A70.60 ||changing beam size ||The beam size may be changed with or without inversion by placing the second lens at the sum or difference of the focal lengths. ||
||6A70.65 ||entrance and exit pupil ||An optical bench setup shows the concept of entrance and exit pupil. ||
||<10% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''PIRA #''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Demonstration Name''' ||<style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot;">'''Subsets''' ||<60% style="&quot; &amp; quot; &amp; amp; quot;text-align:center&amp; amp; quot; &amp; quot; &quot; ">'''Abstract''' ||
||6A70.10 ||model microscope || ||Make a demonstration microscope with a short focal length lens and reading glass. ||
||6A70.12 ||microscope chart || ||A diagram on a wall chart shows the action of a microscope. ||
||6A70.13 ||fake microscope || ||A mirror arrangement and fake microscope make normal objects seem miniaturized. ||
||6A70.14 ||primative microscope || ||A Leeuwenhoek 100 X magnifier is made with a glass bead on the end of a tapered tube. ||
||6A70.20 ||telescope || ||Set up astronomical, terrestrial, and Galilean telescopes for students to look through individually. ||
||6A70.21 ||real telescope || ||Observe with a Questar telescope. ||
||6A70.22 ||sun telescope || ||Make a heliostat for a room with a south facing window. Reference: AJP 38(3),391-2. ||
||6A70.23 ||large telescopes || ||Large telescopes are available on the roof for observations. ||
||6A70.25 ||telephoto lens || ||An illuminated wire mesh is projected on a screen using a telephoto lens setup. ||
||6A70.30 ||camera model || || ||
||6A70.31 ||cameras || ||Several cameras are exhibited. ||
||6A70.35 ||projector model || || ||
||6A70.40 ||superposition of images || ||A wire screen placed at the point where a real image is formed is projected through a second lens to form a combined image. ||
||6A70.45 ||lens combinations || ||A projection lantern double lens system. ||
||6A70.50 ||measuring with moire fringes || ||A long discussion on measuring with moire fringes. Diagrams, Construction details in appendix, p.1346. ||
||6A70.60 ||changing beam size || ||The beam size may be changed with or without inversion by placing the second lens at the sum or difference of the focal lengths. ||
||6A70.65 ||entrance and exit pupil || ||An optical bench setup shows the concept of entrance and exit pupil. ||

Geometrical Optics

PIRA classification 6A

Grayed Demos are either not available or haven't been built yet.

6A.01 Speed of Light

PIRA #

Demonstration Name

Subsets

Abstract

6A01.10

speed of light

Demonstrate speed of light by the path difference method with a fast pulser and fast oscilloscope.

6A01.10

speed of light

pira200

A circuit generates a rapped light pulse that is sent through a fiber optic wire of (20m & 0.1m). The speed of light is shown on oscilloscope by comparing two difference lengths of fiber to a reference signal.

6A01.10

velocity of light

The displacement of a pulse from a fast pulser is viewed on a sampling oscilloscope as the path length is changed. Insert different media in the path.

6A01.10

speed of light - moving reflector

Fancy speed of light apparatus fully documented. Diagrams, Pictures.

6A01.11

pulser circuit

A pulser circuit for the moving reflector speed of light apparatus.

6A01.11

speed of light - fast pulse

Use a high repetition rate pulsed light from TRW to demonstrate the speed of light.

6A01.11

pulser circuit

An LED pulser circuit that emits a 20 ns pulse.

6A01.11

pulser circuit

A light pulser circuit based on the MV 10A LED.

6A01.11

speed of light - N2 laser pulser

A N2 pulsed laser is used in the moving reflector setup.

6A01.12

speed of light - spark source

Construction and properties of a spark light source.

6A01.15

microwave moving reflector

A small microwave pulse generator gives short pulses.

6A01.20

speed of light - two path

Fast flash through two paths to a photomultiplier tube. Diagrams, Pictures.

6A01.21

speed of light - two path

A spot of the display trace of a fast oscilloscope is passed through two different paths to a photomultiplier tube whose output is displayed on the same trace. Diagram, Picture.

6A01.25

errata - corrected diagram

Corrected diagram for figure 2 in AJP 37(8),818 (1969).

6A01.25

speed on light

The MV50 LED is pulsed in this simple time of flight measurement.

6A01.25

speed of light - minimal apparatus

An inexpensive time of flight apparatus using a strobed LED and voltmeter.

6A01.25

speed of light - time of flight

An acoustico-optic modulator chops a laser beam in a time of flight setup.

6A01.25

speed of light choppers

Use a 250 tooth commercial gear as a light chopper.

6A01.26

speed of light - phase shift

Many circuits are given. Features a solid-state electro-optical light modulator to replace the Kerr cell.

6A01.27

optical radar

A commercial (Optitron Inc.) speed of light apparatus with an ultraviolet pulser.

6A01.30

speed of light - rotating mirror

The position of the reflected image from a rotating mirror is measured for clockwise and counterclockwise rotations. Diagram, Appendix, p. 1353.

6A01.31

speed of light - rotating mirror

Photodiode detector with the rotating mirror.

6A01.31

speed of light - rotating mirror

A laser beam is used with the rotating mirror method. Detector circuits given.

6A01.32

speed of light - combined method

A rotating mirror chops the laser beam and a beam splitter gives near and far paths.

6A01.36

Leybold speed of light modification

When both sides of the rotating mirror are exposed, deflections as large as 2 cm can be observed with the unaided eye.

6A01.36

Leybold speed of light rotation rate

Instead of comparing the motor sound to a tuning fork, use a microphone to pick up the motor sound and display it on an oscilloscope, use Lissajous figures with a reference.

6A01.36

more Leybold improvements

Use a solar cell with the AJP 32(7),567 technique.

6A01.36

Leybold speed of light improvements

Find the lateral displacement of the returning beam with a photomultiplier on a carriage.

6A01.36

Leybold speed of light improvements

Use a microphone, oscillator, and oscilloscope to measure the motor frequency of the Leybold speed of light apparatus. Reference: AJP 29(10),711.

6A01.38

speed of light - microwave interfer.

The Doppler beat frequency from the detector is used to drive a spark generator.

6A01.40

speed of light - models

Set up mirrors on the lab bench to help students visualize the standard methods. Do the sound analog (S-81). Set up a rotating mirror.

6A01.50

group velocity of light

Measure the speed of light to 0.02% and verify the relationship between group and phase velocity. Low cost circuit is given.

6A02. Straight Line Propagation

PIRA #

Demonstration Name

Subsets

Abstract

6A02.10

light in a vacuum

Place a flashing light in the bell jar to emphasize the point.

6A02.15

straight line propagation - shadows

6A02.15

straight line propagation of light

A good point source shows straight line propagation of light by shadow projection.

6A02.15

straight line propagation

Cast shadows with a point source.

6A02.16

propagation star

An intense radiation point source limited by a star shaped aperture melts a star shaped pattern on a paraffin backed black foil.

6A02.35

chalk dust

6A10. Reflection From Flat Surfaces

PIRA #

Demonstration Name

Subsets

Abstract

6A10.05

optical design software

Use commercial optical design software to model and display geometrical optics.

6A10.09

reflection model

A string and pulley arrangement shows the minimum path for reflection from a flat surface.

6A10.10

blackboard optics - plane mirror

Blackboard optics - plane mirror.

6A10.11

optical disk with flat mirror

Use a single beam with the optical disk and a flat mirror element.

6A10.11

optical disk with flat mirror

Turn the optical disk with a single beam of light hitting the mirror.

6A10.11

angle of incidence, reflection

Aim a beam of light at a mirror at the center of a disc, rotate the disc.

6A10.15

laser and flat mirror

Shine a laser at a flat mirror on the lecture bench and use chalk dust to make the beam visible.

6A10.18

microwave reflection

Reflect a microwave beam off a metal plate into a receiver.

6A10.20

smooth and rough surface reflection

Chalk dust sprinkled on a mirror blurs the image of a light reflecting onto the wall.

6A10.20

diffuse/specular reflection

Show a beam on light reflecting off a mirror on an optics board. Replace the mirror with a sheet of paper.

6A10.21

diffuse reflection

Hold frosted glass at various angles in a beam of light focused on the wall.

6A10.22

aluminum foil reflection

Same as AJP 50(5),473.

6A10.22

scattering with aluminum foil

Reflect light off a sheet of aluminum foil, then crumple and flatten it to create many facets.

6A10.24

reflection - normal and grazing

Place a lantern and piece of clear glass midway between two walls and show the difference between reflecting by grazing on one wall and normal reflection on the other. Also compare glass and silvered at grazing and normal incidence.

6A10.25

ripple tank reflection

6A10.30

corner reflector

Three reflectors are placed on the inside corner of a box.

6A10.30

corner cube

Two mirrors at 90 degrees or three mirrors mutually perpendicular.

6A10.30

corner reflection

Look at your image in a corner cube.

6A10.31

large corner cube

Use large mirror wall tiles (12 in sq) to make a large corner reflector.

6A10.33

signaling mirror

A plane mirror with a small unsilvered area in the center is used for signaling. Diagram.

6A10.35

perversion

Perversion can be demonstrated in public with a license plate and a plane mirror. Sorry, no inversion.

6A10.37

parity reversal in a mirror

View a Cartesian coordinate system in a mirror.

6A10.40

mirrors at an angle

A candle placed between angled mirrors forms multiple images.

6A10.40

angled mirrors

Two hinged front surface mirrors show multiple images of an object placed between them. Diagram.

6A10.40

hinged mirrors

Mirrors angled at 60 degrees give one object and five images arranged in a hexagon.

6A10.41

hinged mirrors

Place a light between two mirrors hinged together and standing vertically. Place a sheet of clear glass between the mirrors forming an isosceles triangle. A few more variations are given.

6A10.42

hinged mirrors, kaleidoscopes

Hinged mirrors are shown at 60 and 30 degrees along with 60 and 30 degree kaleidoscopes.

6A10.43

angled mirrors - laser spots

The hyperboloid of revolution formed by the successive reflections of a laser beam on two plane angled mirrors is explained by a simple geometrical method.

6A10.44

hinged mirrors theory

The theorem of Rosendahl is applied to the hinged mirror problem to predict the number of images formed at various inclinations.

6A10.45

parallel mirrors

An infinite number of images are formed with a candle between parallel images.

6A10.45

barbershop mirrors

Place objects between parallel mirrors and view them over one of the mirrors.

6A10.50

full view mirror

6A10.50

height of a mirror for full view

Shades are pulled up from the bottom and down from the top covering a mirror until a person can just see their entire height.

6A10.51

large plane mirror

A three foot plane mirror is used to show all of a six foot person.

6A10.60

candle in a glass of water

A candle in front of a plate glass forms an image in a glass of water behind.

6A10.60

plane mirror

A candle is placed in front of a sheet of glass and a beaker of water an equal distance behind. Place the entire apparatus on a rotating table.

6A10.60

location of image

Place a sheet of glass between a burning candle and a glass of water so the image of the candle appears in the glass.

6A10.65

half silvered mirror box

6A10.65

Mirror Box

Two people look into opposite ends of a box containing a half silvered mirror in the center. As the light on one end is dimmed, the light on the other brightens, causing metamorphosis.

6A10.76

sawblade optics

Keep the sawblade perpendicular by lining up the reflection of the board in the sawblade.

6A20. Reflection from Curved Surfaces

PIRA #

Demonstration Name

Subsets

Abstract

6A20.10

blackboard optics - concave mirror

Blackboard optics - concave mirror.

6A20.10

blackboard optics - convex mirror

Blackboard optics - convex mirror.

6A20.10

concave and convex mirrors

pira200

Shine parallel beams at convex and concave mirrors. Use a thread screen for display.

6A20.11

optical disc with curved mirrors

Use the optical disc with multiple beams and curved lens elements.

6A20.11

optical disc - curved mirror

Mount either concave or convex mirrors in the optical disc.

6A20.11

large optical disc

A large translucent screen and large lens elements scale up the Hartl optical disc. Diagrams.

6A20.15

parallel lasers and curved mirrors

Shine parallel lasers at converging and diverging mirrors and use chalk dust to make the beams visible.

6A20.20

spherical abberation in a mirror

Shine parallel rays at spherical and parabolic mirror elements, noting the difference in aberration.

6A20.21

off focal point source

A picture of the caustic formed by parallel laser rays incident on a parabolic mirror at 30 degrees.

6A20.24

concave mirrors - caustics

Directions for making a large cylindrical or parabolic mirror element.

6A20.26

variable curved mirrors

Aluminized mylar stretched over a coffee can makes a variable positive or negative mirror when the can is pressurized or evacuated.

6A20.27

elliptical tank

A filament lamp is placed at one focus of an elliptically shaped wall of shiny aluminum and chalk dust shows the image at the other focus.

6A20.28

ellipsoidal mirror

Compare the light intensity from the lamps at the near and far focus of an ellipsoidal mirror. Directions for making the mirror element. Diagram.

6A20.30

flower in a vase

A hidden flower at the center of curvature of a parabolic mirror appears in an empty vase.

6A20.30

lamp in the socket

A 40 W lamp is projected onto an empty socket.

6A20.30

mirror and rose

Hints for projecting a real image (rose) on an object (vase).

6A20.31

cold candle

Hold your finger in the inverted image of a candle burning at the center of curvature of a parabolic mirror.

6A20.31

large concave mirror

Hold a candle and other objects at the center of curvature of a large convex mirror.

6A20.35

optic mirage

Same as Oc-7.

6A20.35

optic mirage

Derivation of additional "magic separations" of the Optic Mirage that give images.

6A20.35

optic mirage

Two concave mirrors face each other. Images of objects resting on the bottom mirror appear at the center hole of the top mirror.

6A20.36

shine an light on the Optic Mirage

Shine a light on an shiny object in the Optic Mirage and the reflections will look real.

6A20.37

red ball in hemisphere

Looking at a red ball pendulum suspended from the rim of a hemispherical concave mirror makes one puke.

6A20.37

swinging lamp and concave mirror

A lamp pendulum is swung between the center of curvature and the principle focus on a concave mirror.

6A20.40

projected arrow with mirror

A converging mirror is used to project an image of an illuminated arrow onto a screen.

6A20.40

image with a concave mirror

A concave mirror is used to image a lamp filament on a screen or the wall.

6A20.41

projected filament with mirror

A converging mirror is used to project the image of a light bulb filament onto a screen. Masks can be used to stop down the mirror.

6A20.42

rotating liquid mirror

Rotate a pan of glycerine mixed with dark dye, using a lighted object as a source and ground glass screen or TV camera as a detector.

6A20.45

no image with convex mirror

Try to project the image of a filament from a convex mirror.

6A20.45

convex and concave mirrors

Large 16" convex and concave mirrors are shown.

6A20.45

concave and convex mirror

Project a lamp image with a concave mirror, then try convex.

6A20.50

amusement park mirrors

Cylindrical mirrors are made with ten inch radius of curvature.

6A20.51

convex mirror

View the image of your nose in a 1/2" diameter steel ball through a short focal length lens.

6A20.60

lighting a cigarette

Light a cigarette at the focal point of a parabolic mirror concentrating the beam of an arc light.

6A20.60

energy at a focal point

Remove the projection head of an overhead projector and hold a piece of paper at the focal point until it bursts into flame.

6A40. Refractive Index

PIRA #

Demonstration Name

Subsets

Abstract

6A40.10

apparent depth with tv camera

Focus a camera on a spot and then note how far the camera is moved to refocus when a clear plastic block is placed on the spot.

6A40.11

apparent depth

Look down into a tall graduate and estimate the distance to a coin at the bottom.

6A40.12

focusing telescope method

Move a telescope back and forth on a optical bench to focus on the front and then on the back of a block of plexiglass or container of liquid.

6A40.13

microwave index of refraction

Index of refraction is determined by measuring the distance between minima with a movable plane mirror in a container of liquid. Diagram.

6A40.15

refractive index of ice

Freeze water by pumping in a hollow acrylic prism and measure the minimum deviation.

6A40.20

Michelson index of refraction

Place a gas cell in one leg of the Michelson interferometer and evacuate air or let in a gas while counting fringes.

6A40.20

Michelson index of refraction

Count fringes of laser light as air is let into an evacuated chamber in one leg of a Michelson interferometer.

6A40.20

Michelson index of refraction

A vacuum chamber is put in one leg of a Michelson interferometer and fringes are counted as air or a gas is leaked into the chamber. Reference: TPT 6(4),176.

6A40.21

Raleigh refractometer

Improvements on the Raleigh refractometer to make the fringes more visible for easier counting as the air is let back in to the tube.

6A40.25

index of refraction of He and SF6

In addition to letting air (21 fringes) into one arm of the Michelson interferometer, let in He (3 fringes) and SF6 (55 fringes).

6A40.30

Cheshire cat

6A40.30

disappearing beaker

pira200

Place a small beaker in a liquid with an index of refraction matched to the glass (johnsons baby oil or wesson oil).

6A40.31

more Christiansen filters

A table of Christiansen filter pairs. See AJP 25,440 (1957)

6A40.31

Christiansen filters

A mixture of crushed glass and a liquid with the same index of refraction as glass is warmed in a container and exhibits colors. Directions for making a permanent display. Reference.

6A40.36

grating pattern shift

Shine a laser beam through a grating so the beam splits the air/liquid interface and measure the difference in the diffraction pattern for the light passing through the air and liquid.

6A40.36

grating in aquarium

Mount a transmission grating inside an aquarium and measure the diffracted laser beam on the other end with and without water in the tank.

6A40.37

refraction with shadow and cube

A shadow projected through a glass cube has a different length than normal.

6A40.38

refractive index of beer

The ratio of the apparent diameter to the actual diameter of a stick of pepperoni in a glass of beer gives the index of refraction. In the classroom, use a mesh projected on the wall and measure offset of a vertical wire.

6A40.39

Abbe refractometer

A liquid separates the hypotenuses of two right angle prisms.

6A40.40

variable index of refraction tank

Shine a laser beam through an aquarium with an unstirred sugar solution.

6A40.40

variable index of refraction tank

How to make a tank with varying concentrations of benzol and CS2.

6A40.42

gradient index lens

A small gradient index lens is passed around the class. It looks like a glass rod but one sees an inverted image when looking along the axis.

6A40.45

mirage

How to heat a long plate to demonstrate the mirage effect.

6A40.46

mirage

The image from a slide projector is directed just above a brass plate heated with a burner.

6A40.47

mirage with a laser

A laser beam almost grazing a hot plate will show deflection when the hot plate is turned on.

6A40.47

laser beam deflection - thermal grad

An apparatus for cooling a plate to deflect a laser beam downward.

6A40.47

mirage with laser

A laser beam is imaged through a keyhole and the beam then passes through a 1 meter oven.

6A40.47

superior "superior" image

A laser beam passing through a tank of water begins to deflect immediately when heat lamps are turned on. Images are also observed.

6A40.48

not a mirage with a laser

I haven't figured this out and have to go home to eat, so maybe some other time.

6A40.49

mirage explaination note

A note correcting misleading textbook explanations of the mirage.

6A40.50

oil, water, laser

6A40.60

Schlieren image

6A40.60

cheap Schlieren

A small, compact, portable, and inexpensive Schlieren instrument using an ordinary lamp and a light source.

6A40.60

Schlieren, etc.

Show and compare Schlieren, direct shadow, and interferometeric method of detecting small changes in the index of refraction of air. Diagrams, Details in appendix, p. 1352.

6A40.61

Schlieren image of a candle

A simple arrangement with a point source, lens, and candle near the lens, aperture, and screen for lecture demonstration purposes.

6A40.61

Schlieren image of a candle

Laser light is used in Schlieren projection of a candle flame.

6A40.62

single mirror Schlieren system

Two Ronchi rulings are placed at the radius of curvature of a spherical mirror.

6A40.63

Schmidt-Cassegrain schlieren

Two Schmidt-Cassegraion telescopes are used to make a simple inline Schlieren system.

6A40.65

Toepler Schlieren apparatus

A simpler Schlieren setup with colors indicating amount of deviation.

6A40.67

refraction by gases

Shadow project the Bunsen burner (H-137), hold a hot object in one arm on the Michelson interferometer.

6A40.70

short beer

6A40.70

tall beer

Properly designed glassware makes the beer look taller.

6A40.70

cylindrical lens and short beers

Analysis of the apparent inner diameter thick cylinder of a liquid of different index of refraction.

6A40.70

short beers

Paint the inside of the illusion cylinder, (AJP 43(8),741).

6A40.70

beer mugs

Two beer mugs were found that have the same outer dimensions and both appear to hold the same amount of beer when full, but actually differ in volume by a factor of two.

6A40.70

short beer comment

Easy explanation.

6A40.90

plasma laser-beam focusing

An expanded laser beam grazing a flat combustion flame from paint stripper is focused into a line. A second perpendicular flame gives a point.

6A42. Refraction at Flat Surfaces

PIRA #

Demonstration Name

Subsets

Abstract

6A42.10

blackboard optics - refraction

Blackboard optics with a single beam and a large rectangle and prism of plexiglass.

6A42.11

optical disk with glass block

A single beam of light on the optical disc is used to show refraction through a rectangular block of glass.

6A42.12

refraction/reflection from plastic

Rotate a rectangle of plastic in a single beam of light.

6A42.15

optical disc - semicircle

A single beam of light is refracted at the flat but not the curved side if it leaves along a radius.

6A42.20

Big plastic refraction tank

pira200

The light source can be rotated through 270 degreew to show refraction and total internal reflection for both air/platic and plastic/air interfaces.

6A42.20

refraction tank

A rotatable beam of light in a tank of water containing some fluorescein.

6A42.21

Nakamara refraction tank

6A42.22

big plastic refraction tank

6A42.24

force table refeaction tank

A small refraction tank is mounted on a force table.

6A42.27

refraction

Three refraction demos - optical tank, ripple tank, glass block.

6A42.30

refraction model - rolling

6A42.30

refraction model

An axle with independent 1" wheels rolls down an incline with one wheel on cloth, the other on the plain board.

6A42.31

string models of refraction

String models of refraction representing a water tank, prism, thin lens, comma aberration, and astigmatism are shown. Pictures, Construction details in appendix, p.1345.

6A42.32

wavefront strips model

6A42.35

ripple tank refraction

6A42.40

penny in a cup

6A42.40

seeing a coin

Pour water into a beaker until a coin at the bottom previously hidden by the side is visible.

6A42.43

light in a tank

6A42.43

small refraction tank

Position a lamp in an opaque tank so the filament cannot be seen, then add water until the light from the filament is seen over the edge of the tank.

6A42.45

stick in the water

6A42.45

stick in water

A stick appears bent when inserted into water at an angle.

6A42.46

rugged refraction demonstration

Cast a stick in a tumbler filled with clear casting resin. Pass around the class.

6A42.47

acrylic/lead glass refraction

Hold a stick behind stacked lead glass and acrylic blocks. The image of the stick is shifted when viewed off the normal to the surface of the blocks.

6A42.50

minimum deviation of a prism

At minimum deviation light reflected off the base is parallel to that passing through an equilateral prism.

6A42.50

minimum angle of deviation

Project a line filament through a large prism on a rotating platform with and without monochromatic filters. Reference: TPT 7(9),513.

6A42.51

three prism stack

6A42.51

three different prisms

A stack of three prisms of different glass shows different refraction and dispersion.

6A42.55

paraffin prism and microwaves

6A42.55

microwave paraffin prism

Determine the index of refraction of a large paraffin prism with 3.37 cm microwaves.

6A42.60

dispersion in different media

A multiple element prism is made with layers of different plastic and glass.

6A42.65

dispersion of liquids

A hollow prism is filled with a layer of carbon disulfide and a layer of water.

6A44. Total Internal Reflection

PIRA #

Demonstration Name

Subsets

Abstract

6A44.10

blackboard optics

pira200

Multiple beams of light pass through large scale optical elements.

6A44.11

optical disk with prism, semicircle

A single beam of light on the optical disk shows total internal reflection when passed through a prism.

6A44.11

semicircular element on disc

A beam of light entering a semicircular glass disc normal to the curved surface is reflected off the flat side.

6A44.20

critical angle in refraction tank

A beam in a tank of water is rotated until there is total internal reflection at the surface.

6A44.20

refraction tank

Adjust the path of a beam with mirrors in a tank of water with fluorescein. to show total internal reflection.

6A44.20

critical angle/ total internal refle

Shine a beam through the side of a tank containing fluorescein. Rotate a mirror in the tank so the beam passes through the critical angle.

6A44.22

big plastic refraction tank

6A44.25

Snell's wheel

6A44.30

ripple tank total reflection

Vary the angle of incidence of ripple tank waves to a boundary with water depths of 13 and 3 mm.

6A44.35

frust. tot. int. ref.

see 7A50.12

6A44.40

laser and fiber optics

Shine a laser into a curved plastic rod.

6A44.40

laser and fiber optics

A laser is used with a bundle of fiber optics, a curled plexiglass rod, and a 1" square lean rod.

6A44.40

light pipe

Light is projected down a clear plexiglass spiral.

6A44.40

curved glass tube

Shine a bright light source through a curved glass tube.

6A44.40

light pipes--Ulexite

pira200

Several light pipes and fiber optics are shown.

6A44.40

light pipes

Shine a laser into a curved plastic rod.

6A44.41

optical path in fibers

Shine a laser down a bent rectangular bar.

6A44.42

steal the signal

6A44.43

bounce around a tube

A laser beam bounces around a thick walled plexiglass tube due to total internal reflection.

6A44.45

water stream light pipe

Shine a laser beam down the water stream issuing from the orifice of a plexiglass tank of water.

6A44.45

illuminated fountain

Shine a light down a stream of water.

6A44.45

laser waterfall

Shine a laser down the center of a nozzle and it follows the water stream.

6A44.50

light below surface

An underwater light illuminates powder on the surface of water to form a central spot of light.

6A44.50

ring of light

Same as Oe-2.

6A44.50

light below surface

An underwater light illuminates powder on the surface of water to form a central spot of light.

6A44.51

ring of light index of refraction

Find the index of refraction of transparent plates by wetting a filter paper on one side, shining the laser in that side, and measuring the diameter of the light circle.

6A44.52

ring of darkness

Shine a laser through a sample to a white diffusely reflecting surface and measure the darkened circle on the top surface.

6A44.53

water/benzol surface

Total internal reflection from a water/benzol surface.

6A44.54

hidden mercury in a test tube

Mercury in a partially filled test tube cannot be seen from above when immersed in water.

6A44.54

total internal and metallic reflect

View a test tube half full of mercury half in water from an angle of 100 degrees to the incident beam. The glass-air interface is brighter.

6A44.55

black ball turns silver

A soot covered ball appears silver under water due to reflected light from air trapped on the surface of the ball.

6A44.55

soot ball

A ball covered with soot appears silvery in water due to the air trapped on the soot forming an air water interface.

6A44.55

silver soot ball

A ball coated with soot appears silver in water.

6A44.56

glass-air interface

Two thin strips of glass are sealed with an air barrier and immersed in water. Turned to the proper angle to the incident beam it will exhibit total internal reflection.

6A44.56

near critical angle

Use the entrapped air slide in a water bath or air between right angle prisms to show the colors of the transmitted and reflected light near the critical angle. Dispersing the two beams will show complementary spectra.

6A44.59

add water to snow

Project light through snow or chopped ice and add water.

6A44.60

diamond

A thin beam of light is directed on a diamond and the reflections are projected onto a cardboard.

6A44.65

inversion with a right angle prism

Project an image upside down and place a right angle prism in the beam to invert the image.

6A44.65

right angle prism inverter

A right angle prism placed in a projected beam inverts the image.

6A44.66

right angle prism - double reflectio

A beam entering the hypotenuse of a right angle prism is inverted and reversed.

6A44.67

two right angle prisms - inversion

Two right angle prisms are arranged to invert and pervert the image.

6A44.68

prisms

Several prisms demonstrate total internal reflection.

6A44.70

Goos-Haenchen shift

The sideways displacement of a beam at total internal reflection is shown with 3 cm microwaves.

6A46. Rainbow

PIRA #

Demonstration Name

Subsets

Abstract

6A46.10

rainbow

An arc lamp directed at a sphere of water forms a rainbow on a screen.

6A46.10

rainbow

Project a beam through a spherical flask of water and view the rainbow on a screen placed between the light and the flask.

6A46.11

artifical rainbow

Form a vertical circle "rainbow" by placing a tube of water between a prism and screen.

6A46.12

secondary rainbow

Use a single sphere with the back surface coated with a reflecting material to show both primary and secondary bows with increased intensity.

6A46.15

rainbow droplets

Small droplets formed by spraying an atomizer on a soot covered glass plate glisten like colored jewels when viewed at 41 degrees.

6A46.16

rainbow dust

On using small glass spheres to generate bows and halos.

6A46.20

rainbow model

Depict a three dimensional model of the rainbow with strings representing light rays.

6A46.25

rainbow

A mechanical model for demonstrating rainbow formation shows why the rainbow is produced and why size depends on the time of day.

6A46.26

rod and dowel raindrop model

A rod and dowel raindrop model is used to show why a rainbow is bow-shaped.

6A46.30

optical disc with spherical lens

A single beam into a circular glass element is refracted, totally internally reflected, and refracted out again.

6A46.30

rainbow disc

A single beam is used with a spherical glass element on an optical board to show the path of refracted light that produces a rainbow.

6A60. Thin Lens

PIRA #

Demonstration Name

Subsets

Abstract

6A60.10

blackboard optics - thin lens

Blackboard optics are used with convex and concave thin lens elements.

6A60.11

optical disk with thin lens

The optical disk is used with multiple beams and a thin lens element.

6A60.11

optical disc - lenses

Various lens elements are used with the optical disc.

6A60.12

optical disc - refraction at curved

A long plastic slab with a concave surface at one end and a convex surface at the other is used in the optical disc.

6A60.15

ripple tank convex lens

6A60.15

ripple tank - lens model

Refraction due to depth differences over a lens shaped area in the ripple tank.

6A60.16

ripple tank concave lens

6A60.20

parallel lasers and lenses

Parallel lasers are passed through converging and diverging lenses. Chalk dust illuminates the beams.

6A60.20

parallel lasers and lenses

Parallel lasers are used with chalk dust to show the path of rays through a lens and combinations of lenses.

6A60.20

ray tracing with lenses

Show parallel rays passing through a lens element and converging.

6A60.30

thin lens projection

Project the filament of a lamp with a thin lens.

6A60.30

projected filament with lens

pira200

Project the filament of a light bulb on the wall. The lens can be stopped down.

6A60.30

thin lens projection

Project the filament of a lamp with a thin lens.

6A60.30

real image formation

With a source and screen at the ends of a long optical bench, show the two positions a lens will produce an image.

6A60.31

projected arrow with lens

Use an illuminated arrow with a converging lens to project an image on a screen.

6A60.32

thin concave lens

Try to project an image with a thin concave lens.

6A60.33

image location

A set of lenses for demonstration the six general cases for object and image distances.

6A60.35

lens magnification

Place various lenses between a backlit grid and the class.

6A60.40

position of virtual image with TV

Find the virtual image location by focusing on an object through a lens removing the lens, and moving the object to a focused position. Also the apparent depth with TV method.

6A60.45

focal length of a lens - mirror

When a lamp is at the focal length, the image is at the same place if a mirror is placed directly behind the lens.

6A60.48

effect of medium on focal length

Find the focal length of a lens, then find the focal length of the same lens in water.

6A60.49

lenses

All sorts of focal length stuff.

6A60.50

pinholes projected with lens

Pinholes are pricked in a black paper covering a long filament bulb. Bring the multiple images into one image with a converging lens.

6A60.50

action of a lens

Project the images of a filament through several pinholes and then add a lens to collect the many into a single image.

6A60.60

paraffin lens and microwaves

6A60.60

microwave lens

Construct a microwave lens and prisms of stacks of properly contoured aluminum sheets separated by just over one half the wavelength.

6A61. Pinhole

PIRA #

Demonstration Name

Subsets

Abstract

6A61.10

pinhole projection

Place a lamp in a box covered with heavy paper and poke a hole in the paper with a wire 1-2 mm in diameter. Poke more holes for more images. Try different size holes.

6A61.10

pinhole projection

Interpose a metal plate with two holes between a lamp and a screen on an optical bench.

6A61.15

pinholes projected/lens

see 6A60.50

6A61.20

pinhole camera

Place film at the back of a box with a hole.

6A61.20

pinhole camera

Project a lamp filament onto a screen. Vary the distance of the screen and the size of the pinhole. Includes animation.

6A61.21

pinhole camera

A sliding box with has pinhole at one end and a frosted glass at the other. Try a 1" diameter hole in the shutter of a window in a darkened room. Directions on making a pinhole camera.

6A61.22

pinhole imagery

A complete discussion of pinhole imagery.

6A61.23

pinhole camera

A small tube covered with tin foil with a small hole replaces the lens of a TV camera.

6A61.30

fish-eye camera

A pinhole camera filled with water or solid Lucite gives a fish-eye view. Diagram, Pictures.

6A65. Thick Lens

PIRA #

Demonstration Name

Subsets

Abstract

6A65.09

computer assisted optics

The authors describe a program that covers spherical and chromatic aberration in addition to other topics. BASIC, PC, available from authors.

6A65.10

improving an image with a stop

Use a stop to improve the image through a short focal length lens.

6A65.11

depth of focus

Use a six inch long glowing wire as an extended object for showing the effect of stopping down a lens.

6A65.15

optical disc - circular glass plate

Use a circular plate of glass with the optical disc as an example of a thick lens.

6A65.20

chromatic aberration

A diaphragm moved near the focus selects red or blue light from beams passing through the edge of a lens.

6A65.21

aplanic properties of a sphere

Aplanic systems show no spherical aberration or coma for some special position of object and image demonstrated here with a spherical lens.

6A65.21

chromatic aberration

Project spots of light on a screen from several points on a lens. Note chromatic aberration and then add a second correction lens.

6A65.22

chromatic aberration

Show the image formation distance for red and uv light using a fluorescent screen to display the uv.

6A65.23

lens aberrations with a laser

Good quality telescope and microscope objectives are used to show aberrations in optical systems.

6A65.24

chromatic and spherical aberration

Use diaphragms with central, annular, and other openings to show spherical and chromatic aberration.

6A65.30

barrel and pincushion distortion

Project an illuminated wire mesh with a large lens. Place a diaphragm between the lens and the mesh for barrel distortion and between the lens and the screen for pincushion distortion.

6A65.31

off axis distortion

Parallel rays of light pass through a lens element held off axis.

6A65.34

astigmatism

Focus light from a circular hole on a screen, then add a cylindrical lens.

6A65.35

astigmatism and distortion

An illuminated wire mesh is projected onto a screen with a short focal length condenser lens. Turn the lens about an axis parallel to either set of wires and the horizontal and vertical wires will focus at different points.

6A65.40

spherical aberration

Project an image with a spherical planoconvex lens. Stop the outer portion of the lens, then the center.

6A65.45

abberation with a plano convex lens

A series of parallel beams around the outside edge of a plano convex lens made visible with chalk dust are better focused when the light enters the curved side.

6A65.46

spherical abberation and coma /laser

Diagram and pictures of a setup to project lens aberrations with a laser.

6A65.52

water lens

A beam of light is directed through a round flask filled with water.

6A65.52

fillable air lenses

Convex and concave lenses are filled with water and air in water and air.

6A65.53

spherical lens

Compare a thermometer at the center of a water filled flask to one at the far side. Picture.

6A65.54

wine bottle lens

Fill a round flask with a wine bottle bottom with water and fluorescein to show diverging light.

6A65.55

watch glass lens

A vertical lens can be formed by pouring various liquids into a watch glass.

6A65.56

CHOICE OXIDE

CHOICE OXIDE GLASS LAMP is viewed through a tube filled with water.

6A65.58

light beam strikes rod

A light beam incident on the side of a glass rod at some angle will produce a cone with the half angle equal to the angle of incidence.

6A65.60

plastic lenses

The advantages of plastic lenses.

6A65.70

Fresnel lens history

An article on the discovery of stepped lenses.

6A65.70

Fresnel lens

Fresnel lens magnification. Animation showing construction of a Fresnel lens.

6A70. Optical Instruments

PIRA #

Demonstration Name

Subsets

Abstract

6A70.10

model microscope

Make a demonstration microscope with a short focal length lens and reading glass.

6A70.12

microscope chart

A diagram on a wall chart shows the action of a microscope.

6A70.13

fake microscope

A mirror arrangement and fake microscope make normal objects seem miniaturized.

6A70.14

primative microscope

A Leeuwenhoek 100 X magnifier is made with a glass bead on the end of a tapered tube.

6A70.20

telescope

Set up astronomical, terrestrial, and Galilean telescopes for students to look through individually.

6A70.21

real telescope

Observe with a Questar telescope.

6A70.22

sun telescope

Make a heliostat for a room with a south facing window. Reference: AJP 38(3),391-2.

6A70.23

large telescopes

Large telescopes are available on the roof for observations.

6A70.25

telephoto lens

An illuminated wire mesh is projected on a screen using a telephoto lens setup.

6A70.30

camera model

6A70.31

cameras

Several cameras are exhibited.

6A70.35

projector model

6A70.40

superposition of images

A wire screen placed at the point where a real image is formed is projected through a second lens to form a combined image.

6A70.45

lens combinations

A projection lantern double lens system.

6A70.50

measuring with moire fringes

A long discussion on measuring with moire fringes. Diagrams, Construction details in appendix, p.1346.

6A70.60

changing beam size

The beam size may be changed with or without inversion by placing the second lens at the sum or difference of the focal lengths.

6A70.65

entrance and exit pupil

An optical bench setup shows the concept of entrance and exit pupil.

Demonstrations

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fw: GeometricalOptics (last edited 2020-03-14 22:00:37 by srnarf)