Mode matching calculation for green - Yarm
I did again the mode matching calculation. The previous one was using 1064nm as wavelength, so it was wrong.
The seed beam waist and its position are the same as in elog 8637. The new results are shown in the attached graphs.
I got the following values for focal lengths and positions of the two Mode Matching lenses:
Focal length (m) Distance from the Faraday output (m)
lens1 0.125 0.1829
lens2 -0.200 0.4398
L 1.000 1.4986 (fixed)
The position of the lens L has changed because the path lengh has been slightly reduced.
The Coupling factor for he astigmatic beam is C = 0.959 (it is C = 0.9974 if we consider the beam as non astigmatic).
I put the lenses and aligned the beam up to the shutter, which has been moved from its initial position because the beam size on it was too large.
TO DO
The green beam needs to be aligned and sent into the arm cavity.
Polarization has to be checked.
Many beams still have to be dumped, both in IR and Green paths.
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