Last bit of oven matching for now.
I moved the lens before the oven position back along the beam path by about 1cm - waist should be just above position 9 in this case. Note - due to power-findings from previous time I'm maximising the power into the head to reduce the effect of offsets.
From position 9:
Position A1_13.5%_width A2_13.5%_width
(mm) (um mean) (um mean)
-1 121.1 123.6
0 112.5 113.8
1 106.4 106.1
2 102.9 103.4
3 103.6 103.6
4 106.6 107.4
5 111.8 112.5
6 118.2 120.1
7 126.3 128.8
8 134.4 137.1
9 143.8 146.5
10 152.8 156.1
11 163.8 167.1
12 175.1 176.4
13 186.5 187.0
14 197.1 198.4
15 210.3 208.9
16 223.5 218.7
17 237.3 231.0
18 250.2 243.9
19 262.8 255.4
20 274.7 269.0
21 290.4 282.3
22 304.3 295.5
23 316.7 303.1
Note - had to reduce power due to peak saturation at 15mm - don't think scale changed, but be aware just in case. And saturated again at 11. And again at 7. A little bit of power adjustment each time to make sure the Beamscan head wasn't saturating. Running the fit gives...
 
OK. The fit is reasonably good. Residuals around the area of interest (with one exception) are <+/- 2um and the waists are 47.5um (vertical) and 50.0um (horizontal) at a position of 9.09 on the bench. And the details of the fitting output are given below.
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Vertical Fit
cf_ =
General model:
cf_(x) = w_o.*sqrt(1 + (((x-z_o)*1064e-9)./(pi*w_o.^2)).^2)+c
Coefficients (with 95% confidence bounds):
c = 5.137e-06 (4.578e-06, 5.696e-06)
w_o = 4.752e-05 (4.711e-05, 4.793e-05)
z_o = 1.04 (1.039, 1.04)
cfgood_ =
sse: 1.0699e-11
rsquare: 0.9996
dfe: 22
adjrsquare: 0.9996
rmse: 6.9738e-07
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Horizontal Fit
cf_ =
General model:
cf_(x) = w_o.*sqrt(1 + (((x-z_o)*1064e-9)./(pi*w_o.^2)).^2)+c
Coefficients (with 95% confidence bounds):
c = 3.81e-06 (2.452e-06, 5.168e-06)
w_o = 5.006e-05 (4.909e-05, 5.102e-05)
z_o = 1.04 (1.04, 1.04)
cfgood_ =
sse: 4.6073e-11
rsquare: 0.9983
dfe: 22
adjrsquare: 0.9981
rmse: 1.4471e-06
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