last Friday with Manar, we took some thermal images of the Alpnavov compressor box.
I post a small document to summarize some points :
- the 2 mirrors used to make the CVBG injection are polarized thin-film mirrors... thus sensitive to the beam polarization.
there is also a half-wave plate on the input path...
are we sure that the beam polarization is properly set with the Onefive laser injecting the amplifier ?
(Alphanov used their own seeder).
- the CVBG temperature seems normal without too much difference between profiles and values.
- the 2 thin-film mirrors seem quite hot (45°) compared to the rest of the setup.
a basic calculation about power thermally radiated gives an absorbed power of around 0.2W which is equivalent to more than 1000ppm of absorption.
is this estimation correct? could it be the confirmation of some misalignment that traps some power inside the mirror substrate?
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