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Entry  Mon Oct 12 17:27:20 2009, Koji, Configuration, SAFETY, Stray beam blocking PSL.png
    Reply  Mon Oct 12 18:38:07 2009, Jenne, Configuration, SAFETY, Stray beam blocking 
       Reply  Mon Oct 12 20:01:13 2009, Koji, Configuration, SAFETY, Stray beam blocking 
          Reply  Mon Oct 12 22:15:15 2009, rana, Configuration, PSL, Stray beam blocking 
    Reply  Mon Oct 12 19:53:44 2009, Koji, Configuration, SAFETY, Stray beam blocking 
Message ID: 2082     Entry time: Mon Oct 12 17:27:20 2009     Reply to this: 2084   2085
Author: Koji 
Type: Configuration 
Category: SAFETY 
Subject: Stray beam blocking 

Steve, Kiwamu, and Koji

We went through the PSL table to make sure any strong beam did not hit the wall.

We found that the reflection of Stephanie's OSA returned its path down to the beamsplitter.
This BS reflect that beam to the wall. That was fixed.

The surprising was that the relatively strong beam (~1mW?) went through the steering mirror
just before the PMC. We put thorlabs razor blades. I am still thinking what this indicates...
because the beam had been blocked if it was such from long time before.

During the work we found some stray optics such as a cube BS, a flipper mirror, and so on.
We can see them in the photo as those enclosed with yellow circles.
One of the beams was obtained from the reflection of the ND filter (...almost illeagal), and 
was even hittting a metal fixture for the BS cube.

If someone uses these components for useful purposes,
please let me(Koji) know. Otherwise, they are removed next week.

The other thing we found was the bright scatter from the EOM for the PMC.
As this scatter is so blight, I am going to align it.

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