13 September 2012 Fabrication and testing of germanium grisms for LMIRcam
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We diamond fly cut 2 sets of germanium grisms for the LMIRcam 3-5 micron Fizeau imager for the combined focus of the Large Binocular Telescope (LBT). The grisms mount in a filter wheel near a pupil to enable moderate resolution (R~300) spectroscopy. Both sets have a measured blaze angle of 2.9°. The first set has a groove period of 40 lines/mm and will be used in first order with peak efficiency at 3.6 μm. The second set has 32 lines/mm. It can operate in first order with an efficiency peak near 4.4 μm and in second order with a peak near 2.3 μm. First results from testing the grisms in the instrument on the sky with the LBT are presented.
© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Paul J. Kuzmenko, Paul J. Kuzmenko, Steve L. Little, Steve L. Little, Liesl M. Little, Liesl M. Little, John C. Wilson, John C. Wilson, Michael F. Skrutskie, Michael F. Skrutskie, Philip M. Hinz, Philip M. Hinz, Jarron M. Leisenring, Jarron M. Leisenring, Olivier Durney, Olivier Durney, } "Fabrication and testing of germanium grisms for LMIRcam", Proc. SPIE 8450, Modern Technologies in Space- and Ground-based Telescopes and Instrumentation II, 84503P (13 September 2012); doi: 10.1117/12.926674; https://doi.org/10.1117/12.926674

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