Specification of Broadband Filters for JH and HK Spectroscopy

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1.3 - 2.3 um Broadband Filter
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* Center wavelength      1.8 micron
* Cut-on                 1.3 micron
* Cut-off                2.3 micron
* Cut-on slope           < 3% at 1.3 micron
* Cut-off slope          < 3% at 2.3 micron
* Peak transmission      > 80% average transmission (>90% goal)
* Ripple specification   Less than  5 % of average transmission
* Out of band blocking   E-4 0.8-1.3 micron
                         E-5 2.3-2.6 micron
* Physical dimension     80mm diameter 0.1mm
* Clear aperture         70mm diameter (minimum)
* Thickness              4-8mm
* Substrate flatness     < Lambda/4
* Substrate parallelism  < 10 arcsec
* Angle of Incidence     ~6.2 degree
* Operating temperature  120K
* Operating range        0.85-2.5 micron
* Quantity               2
* Free of pinhole defects.


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0.9 - 1.8 um Broadband Filter
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* Cut-on                 0.9 micron
* Cut-on slope           < 3% at 0.9 micron
* Cut-off                1.78 micron
* Out of band blocking   E-4 0.7-0.9 micron
                         E-5 1.9-2.6 micron
* Slope                  < 3%
* Peak transmission      > 90% average
* Quantity : 2
(# Detector operating range is 0.85-2.5 micron.)