David Notebook: Difference between revisions

We then looked for 633 generation by eye by sending the prism output to a mirror and then perpendicular off the table at eye level. We still wore goggles as they should have little effect on a 633 beam but would help with 780 or 1064 if something went wrong. We immediately saw a red beam, but believe it to be a small amount of 780 internally reflecting in the prism and scattering. Further searching revealed another red beam (perhaps of slightly different color) that flashed when we were ramping the piezo. It was highly angularly dependent, but once we found it the first time and knew where to look it was fairly easy to find again. This beam also changed intensity when we changed the 1064 or 780 beam intensities. Additionally it disappeared when turning off the RF signal (we were using the old locking circuit and had it set to ramp so that it would exhibit peak broadening), and would disappear when moving the cavity piezo to a "bad" position. This is the exact behavior we would expect from a 633 beam, but we couldn't find a signal with the OSA yet, which will be our next step. We want to try slightly adjusting the 780 alignment as well to see how this affects the candidate 633 beam intensity.