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Message ID: 1674     Entry time: Sun Jul 17 14:17:27 2016
Author: awade 
Type: DailyProgress 
Category: Mode matching 
Subject: Tape fleck in S-EOM2 (NF-4004) aperature and lens move 

I was concerned about some of the spacial features I was seeing after the second broadband EOM.  On closer inspection there was a small fleck of what looked like plastic tape in the input aperture (pictured).  

Fleck of plastic, now removed 

I removed the fleck and it looks all clear now.  

Also, I thought maybe the beam was just a the limit of size for one axis. I moved the lens (PLCX-25.4-64.4-UV-1064) forward to z = 1252 mm. The re measured beam had the fitted characteristics:


Horz. beam waist = 194.3474 um
Horz. beam waist position = 1472.415 mm
Vert. beam waist = 140.8421 um
Vert. beam waist position = 1418.9487 mm

 

Attachment 2: data20160717_south_AfterSecondEOMAFTERTapeRemoval.txt  138 Bytes  | Hide | Hide all
0.0254	0.0000005	0.0000005
1	691	605
3	561	399
5	417	263
7	329	438
9	528	842
11	699	1144
13	851	1267
15	965	1458
17	1053	1570
19	1170	1769
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