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Entry  Tue Sep 24 20:28:47 2013, Evan, DailyProgress, RefCav, CCD camera for monitoring refl beam south_refcav_unlocked.jpgsouth_refcav_locked.jpg
    Reply  Wed Sep 25 10:15:49 2013, rana, DailyProgress, RefCav, CCD camera for monitoring refl beam 
       Reply  Wed Sep 25 12:23:25 2013, Evan, DailyProgress, RefCav, CCD camera for monitoring refl beam south_unlocked_watec.jpgsouth_locked_watec.jpg
Message ID: 1353     Entry time: Tue Sep 24 20:28:47 2013     Reply to this: 1354
Author: Evan 
Type: DailyProgress 
Category: RefCav 
Subject: CCD camera for monitoring refl beam 

I placed a CCD camera behind the steering mirror directly before the south RFPD in the hopes of getting a handle on the shape of the refl beam while the refcav is locked or unlocked. Unfortunately I think the transmission through the mirror is too low; you can barely make out the refl spot when the cavity is unlocked, and it disappears when the cavity is locked.

Previously (PSL:798), Frank and Tara used a CCD camera to monitor the reflection off the RFPD itself. This reflection has enough power to be seen on an IR card, so perhaps this is the way to go (if we trust the face of the RFPD to not distort the beam).

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