This was a conference paper that I was a co-author on where we developed a infrared polarization system for chemical detection. My contribution was the design, tolerancing, building, and testing of the optical system. The goal was to make a low cost short wave thermal imager (SWIR) to test polarization detection for certain chemicals. You can read the details in the paper. The design was very successful for the intended application as a first generation prototype. It was optimized for loose tolerances, easy fabrication of the optical elements, and passive assembly. By making the optics fit into a commercial telescope focuser and building some simple custom adaptors we turned something that could have cost many tens of thousands of dollars into an instrument that was only a few thousand dollars. Moreover, we were able to utilize rapid prototype parts for the filter holder enabling us to have more complex parts in that component without driving fabrication costs.
Citation: Julia Craven-Jones, Leah Appelhans, Eric Couphos, Todd Embree, Patrick Finnegan, Dennis Goldstein, David Karelitz, Charles LaCasse, Ting S. Luk, Adoum Mahamat, Lee Massey, Anthony Tanbakuchi, Cody Washburn, Steven Vigil, "A polarization system for persistent chemical detection," Proc. SPIE. 9613, Polarization Science and Remote Sensing VII, 96130B. September 01, 2015 doi: 10.1117/12.2188718 PDF