A custom IR spot scanning experiment was constructed to project subpixel spots on a mercury cadmium telluride focal plane array (FPA). The hardware consists of an FPA in a liquid nitrogen cooled Dewar, high precision motorized stages, a custom aspheric lens, and a 1.55 and 3.39 μm laser source. By controlling the position and intensity of the spot, characterizations of cross talk, saturation, blooming, and (indirectly) the minority carrier lifetime were performed. My contribution was the design of the custom aspherical optics that enabled a diffraction limited spot while still being easy to fabricate. You can read the full details in the paper.
Citation: Soehnel, Grant; Tanbakuchi, Anthony, "Simulation and experimental characterization of the point spread function, pixel saturation, and blooming of a mercury cadmium telluride focal plane array,” Applied Optics 51(33) 7987-7993, Nov 2012. PDF