Camilla, Gerardo.

For ITMY, we installed CHETA VP D1700340-type02 as planned in A-1F VP3:

• Primary VP sealing optic D1100439-type02 SN 002 0.5" thick AR 1064nm, 10.6um (Coherent)
• Secondary dust-cover optic D1100485-type03 SN 005 0.25" thick AR 1064nm, 4.6um (Edmund Optics)
• This went to plan as was installed in  90917, assy D1700340-type002-003

For ITMX, we did not install a CHETA VP, as we had issues with the primary optic. We instead installed a blank in A-1C VP4 in 90949.

• Secondary dust-cover optic D1100485-type03 SN 001 0.25" thick AR 1064nm, 4.6um (Edmund Optics)
  • Initially when we pulled first contact from this, a ~ 5mm x 5mm piece of the AR coating pulled off. Photos of optic and FC attached. 
  • This is not expected as is our standard ZnSe cleaning procedure. GariLynn said that this could be caused by poor optic cleaning by manufacturers prior to coating. 
  • We then planned to use D1100485-type02 SN 001 0.25" thick AR 1064nm, 10.6um (Coherent) in it's place, but on assembly we found:
• Primary VP sealing optic D1100439-type02 SN 001 0.5" thick AR 1064nm, 10.6um (Coherent)
  • Once this full assembly was together and all first contact pulled, I noticed a dark speck ~0.75" from the edge of the air side of the optic.
  • Dis-assembled, re cleaned and re inspected. Speck seemed to be a small < 1mm x 1mm hole in coating as it appeared dark or light defending on lighting conditions. 
  • I think I would have seen this in the original inspections if it was there so think this coating was also pulled off by first contact. 
  • As this is a vacuum sealing optic, it will not be installed.