sheila.dwyer@LIGO.ORG - posted 17:20, Friday 26 January 2018 - last comment - 23:59, Friday 26 January 2018(40297)
OPO aligned for 532
Terry, Nutsinee, Sheila
After looking at the fiber collimators we decided to try swapping them so that the one that has a greenish tint in the lens is used for 1064 and the one that looks very clear is used for 532, based on advice from Lisa, Lee and Maggie. After doing this we were able to align the cavity and saw that our mode matching isn't too bad although we haven't tried to optimize it by moving any lenses yet.
Terry, Nutsinee
Here I attached the waist measurement and fit of 532nm coming out of the correct green coupler. The Thorlabs beam profiler we use is not great with beam diameter < 1000um for 532 so we took that into account this time. The waist size we got was 183um (radius) located 270mm away from the coupler.
I also attached a photo of the couplers we have. Couldn't capture the reddish color very well but the left coupler was for 532 and the right coupler was for 1064.