The substrate must be 1“ in diameter and pass >96% light from 0.5 micron to 2.45 microns. The optical surfaces must be Lambda/8 or better at 632nm, at least 5mm thick. The thickness must be matched to 0.2mm or better. An example substrate would be the Thorlabs Magnesium Fluoride Window WG61050. These substrates could be vendor supplied or supplied by CHARA to the vendor.
Each optic would have a long pass dichroic surface on one side with >50% reflectivity from 0.45 to 0.5 microns, and would pass >96% from 0.55 to 2.45 microns. We also desire as much light as possible between 0.5 and 0.55 microns also pass through the optic. The other side would be anti-reflection coated, ideally for 0.5-2.45 microns but 0.6-2.45 microns is acceptable.
| Company|| Contact|| Notes|| Cost Per Unit|| TODO|| IR Transmission|| CaF2 Substrate
| Andover|| Robert Pursel|| Cutoff very close to 0.5um|
Includes substrate N-BK7
| $583|| Get quote for infrasil substrates (done 2013-12-12 no responce)|| >93%|
| Contacted 2014-01-29 concerning CaF2 substrates
| || || Update coating CaF2 substrates we supply|| $575|| Plus $90 for substrate makes $665s|| Fine|| Closest to our spec.
| Cascade Optical|| || Bit long 550nm|
| $350|| || >93%|| Contacted 2014-01-29 concerning CaF2 substrates. Response 2014-02-03 $2100 for batch, or the same $350.
| Casix Optics|| Xanthe Lin|| No response yet|| || || ||
| c-optical|| || No response|| || || ||
| ISP Optics|| Andrew Houseman|| No Curve Given|
| Clarify >50% reflectivity and no rear-surface AR coating.|| >95%||
| || || Updated Quote|
| || || Second quote seems to have cleared this up 2013-12-13. Asked 2014-01-29 if they can shorten delivery time. They can 4 wks. Want as much warning as possible and spare substrates.
| Layertec|| Stefan Gotz|| 510nm|
| Quote needs a rear AR coating added|
They say it's because the BW is so high.
Using our substrates will cost $200 more.
(rear AR coating assumed)
| omega Filters|| Kirk Winchester|| No Curve|
No broken down.
| $580|| Corning 7980 - FS|| >90%|| Contacted 2014-01-29 concerning CaF2 substrates. Sent 'Typical' curve in response. States that CaF2 is harder to work with and wants to know why we need it. Quote on the way. Judit confirms that Fused Silica is OK.
| Optimaxsi|| Erin Peacox|| No Bid|| || || ||