Light Pipes - Ulexite, 6A44.40
Topic and Concept:
Geometrical Optics, 6A44. Total Internal Reflection
pira200 Listed
Location:
Cabinet: Optics (OP)
Bay: (A2)
Shelf: #1
Abstract:
Ulexite is a naturally occurring mineral which consists of parallel fibers. Each fiber may act as a light pipe.
Equipment |
Location |
ID Number |
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Ulexite crystal |
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Setup and Procedure:
Place the Ulexite sample above printed text. As one moves one's head around, or moves the Ulexite, it appears as if the text is written on the top of the ulexite. The effect is striking.
In above picture, observe the disjunction in each line of text, for example "fiber" is a little above "optic". The camera lens was directly above the blue line at the top of the page of the printed text.
Discussion:
Ulexite is birefringent, and the "light pipe" phenomenon it displays is a consequency of the birefringence and the fibrotic structure.
Videos:
References:
Wikipedia: https://en.wikipedia.org/wiki/Ulexite