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Message ID: 3695     Entry time: Tue Oct 12 01:54:32 2010
Author: kiwamu 
Type: Update 
Category: Green Locking 
Subject: mode matching to doubling crystal on PSL table 

I improved the mode matching of the incident beam to the doubling crystal on the PSL table.

As a result it apparently got better (i.e. brighter green beam), but it's not the best because now the beam is a little too tightly focused on the crystal. 

I am going to work on it again someday after seeing the beat note signal.

 

- The measured waist sizes are

    41.94 [um] for vertical mode

   42.20 [um] for horizontal mode

while the optimum waist size is 50 um (see entry #3330).

The plot below shows the beam scan data which I took after improving the mode match.

PSL_doubling.png

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