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Message ID: 1662     Entry time: Thu Jul 7 17:59:34 2016
Author: awade 
Type: DailyProgress 
Category: Mode matching 
Subject: South path laser beam profile (again) 

I have put down and pulled up the first section of the south path a few times.  I've developed a habbit of packing optics in at close range and we decided that this was not so great when we had plenty of space.  Starting at the begining again I had another go at measuring the mode strait out of the laser.  Data is attached below and z0 = 0 is referenced to the front of the laser head.

I changed the power at point 8 and there seems to be a distict change in slope there.  There are two waveplates, a PBS (which I think is UV silica) and a W2 coated window that is definitly fused silica.  

This data is much cleaner than earlier measurment and I'm not sure if the change in waist (for the measurment) is enought to be worried about.  I will use these values for subsqutent modematching.  

Horz. beam waist = 193.4873 um
Horz. beam waist position = 27.7636 mm
Vert. beam waist = 139.5525 um
Vert. beam waist position = 34.6003 mm

 

 

Attachment 1: data20160707_south_directLaserprofileValues.txt  259 Bytes  | Hide | Hide all
0.0254	0.0000005	0.0000005
1	774	955
2	850	1049
3	927	1166
4	984	1251
5	1020	1330
6	1121	1447
7	1180	1554
8	1375	1831
9	1481	1966
10	1563	2045
11	1637	2186
12	1723	2297
13	1794	2394
14	1852	2477
15	1965	2662
16	2048	2750
17	2102	2867
18	2168	2916
19	2231	3080
Attachment 2: data20160707_south_directLaserprofileValues.eps  136 kB  | Hide | Hide all
data20160707_south_directLaserprofileValues.eps
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