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Entry  Thu Jun 3 00:52:37 2010, tarac, Laser, Laser, Aligning AOM 97-02848-01r0.pdf
    Reply  Thu Jun 3 08:42:44 2010, Frank, Laser, Laser, Aligning AOM AOM3080-194.JPG
       Reply  Thu Jun 3 14:47:58 2010, Frank, Laser, Laser, Aligning AOM 
          Reply  Thu Jun 3 15:45:39 2010, Frank, Laser, Laser, Aligning AOM 
             Reply  Thu Jun 3 22:00:21 2010, Frank, Laser, Laser, Aligning AOM 
                Reply  Fri Jun 4 00:03:17 2010, Jenne, Computing, Environment, Spam 
                   Reply  Sat Jun 5 16:17:05 2010, Koji, Computing, Environment, Spam 
Message ID: 142     Entry time: Thu Jun 3 14:47:58 2010     In reply to: 141     Reply to this: 143
Author: Frank 
Type: Laser 
Category: Laser 
Subject: Aligning AOM 

Quote:

Quote:

 I'm aligning the AOM and maximizing the diffracted beam's power by positioning the AOM and adjusting the beam size by moving the lens.

For single pass, the maximum efficiency I could get is only ~60%, so for double pass, the power will be down to 36%, but for now I'll settle with this number.

I could not find the manual for Crystal technology AOM 3080-194. The closest one is model 3080-197 which is attached below.

I'm not sure what is the difference between the two model, but 3080-197 has 70% diffraction efficiency.

Because of adjusting the lens, the RefCav's beam path also changes, now I have to realign RefCav again.

 

  Another step for AOM alignment is adjusting the mirror that reflects the transmitted beam back to the AOM again.

The distance between the mirror and the center of the AOM should be the same as ROC of the mirror.

After this I should be able to start locking ACav.

 did you measure the power of the vco? How much is it if you tune it to maximum?

Here a copy of a general datasheet for the 3080-194. maximum efficiency is ~80% @2W RF power. You should ask peter about the detailed datasheet which comes with each AOM and contains measured values for the one you are using. Measured values depend on the beam size and RF power. Typical values are 87% in reality.

AOM3080-194.JPG

 Oh, I see, the beam diameter is 1100 um, I use 150um. I'll try changing the beam size and see what happens. Thanks Frank. I'll measure the power of the VCO too.

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