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Short-wave infrared (SWIR) imaging polarimetry has widespread applications in telecommunication, medical imaging, surveillance, remote-sensing, and industrial metrology. In this work, we design, fabricate, and test an achromatic SWIR elliptical polarizer, which is a key component of SWIR imaging polarimetry. The elliptical polarizer is made of a patterned linear polarizer and a patterned optical elliptical retarder. The linear polarizer is a wire grid polarizer. The elliptical retarder is constructed with three layers of nematic phase A-plate liquid crystal polymer (LCP) films with different fast axis orientations and physical film thicknesses. For each LCP layer, four arrays of hexagonal patterns with individual fast-axis orientations are realized utilizing selective linearly polarized ultraviolet (UV) irradiation on a photo-alignment polymer film. The Mueller matrices of the optical filters were measured in the wavelength range 1000 nm to 1600 nm and compared with theory. Our results demonstrate the functionality and quality of the patterned retarders with normalized analyzer vector parameter deviation below 7% over this wavelength range. To the best of our knowledge, this work represents the first polymer-based patterned elliptical polarizer for SWIR polarimetry imaging applications. 

We calibrate and test a division-of-focal-plane red–green–blue (RGB) full-Stokes imaging polarimeter in a variety of indoor and outdoor environments. The polarimeter, acting as a polarization camera, utilizes a low dispersion microretarder array on top of a sensor with Bayer filters and wire-grid linear polarizers. We also present the design and fabrication of the microretarder array and the assembly of the camera and validate the performance of the camera by taking multiple RGB full-Stokes images and videos. Our camera has a small form factor due to its single-sensor design and the unique capability to measure the intensity, color, and polarization of an optical field in a single shot.