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Reports until 10:45, Monday 28 April 2014
H1 TCS (TCS)
aidan.brooks@LIGO.ORG - posted 10:45, Monday 28 April 2014 (11598)
TCS CO2X - extinction ratio issue (& Beckhoff glitches)

Aidan, Thomas, Greg, Dave H, Matt H.

We worked on getting the polarizers aligned after the half wave plate on Friday. Despite our best efforts, we could get an extinction ratio better than 500:1 (so 20mW off the polarizers for 10W into them). We achieved a lot better than this at LLO (~ 250,000:1). We're going to revisit the alignment of the first polarizer after the laser (which is supposed to clean up the polarization of the laser).

We got several MOTOR ERROR warnings whilst using the rotation stage on Friday which required the Beckhoff system to be reset each time. Also, the rotation stage is now only turning in a range of about 5 degrees or so. Vern is looking into this today.

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