Jiang Linan, Miller Sawyer, Tu Xingzhou, Smith Matt, Zou Yang, Reininger Francis, Pau Stanley
Opt Express. 2022 Jan 17;30(2):1249-1260. doi: 10.1364/OE.445253.
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.
短波红外（SWIR）成像偏振测量在电信、医学成像、监视、遥感和工业计量学中有着广泛的应用。在这项工作中，我们设计、制造并测试了一种消色差SWIR椭圆偏振器，它是SWIR成像偏振测量的关键部件。该椭圆偏振器由一个图案化的线性偏振器和一个图案化的光学椭圆延迟器组成。线性偏振器是一个线栅偏振器。椭圆延迟器由三层具有不同快轴方向和物理膜厚的向列相A板液晶聚合物（LCP）薄膜构成。对于每一层LCP，利用在光取向聚合物薄膜上的选择性线性偏振紫外（UV）照射实现了具有各自快轴方向的四个六边形图案阵列。在1000 nm至1600 nm波长范围内测量了光学滤波器的穆勒矩阵，并与理论值进行了比较。我们的结果表明，在该波长范围内，图案化延迟器的功能和质量良好，归一化分析器矢量参数偏差低于7%。据我们所知，这项工作代表了首个用于SWIR偏振测量成像应用的基于聚合物的图案化椭圆偏振器。
