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Entry  Tue Sep 1 17:07:06 2015, ericq, Update, LSC, IR beatnote confusion 
    Reply  Tue Sep 1 17:38:58 2015, ericq, Update, LSC, IR beatnote confusion 
       Reply  Wed Sep 2 13:44:04 2015, ericq, Update, LSC, IR beatnote confusion 
          Reply  Thu Sep 3 17:15:26 2015, ericq, Update, LSC, IR beatnote confusion GREENvIRbeats.pdf
             Reply  Fri Sep 4 09:36:48 2015, Steve, Update, LSC, IR beatnote confusion..... 
Message ID: 11557     Entry time: Tue Sep 1 17:38:58 2015     In reply to: 11556     Reply to this: 11559
Author: ericq 
Type: Update 
Category: LSC 
Subject: IR beatnote confusion 
Quote:

Maybe we just don't understand the splitter/combiners.

After an email from Eric G, I think this is the case.

If you read the text at Thorlabs about Fiber-Based Polarization Beam Combiners/Splitters, it suggests that these things take input beams both aligned to their slow axes, and outputs one field along the slow, and one orthogonal to it on the fast axis. Which is exactly what we don't want for a beat. 

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