Optimal Design of an Achromatic Angle-Insensitive Phase Retarder Used in MWIR Imaging Polarimetry  

作　　者：康果果 谭峭峰 金国藩 

机构地区：[1]State Key Laboratory of Precision Measurement Technology and Instruments, Tsinghua University, Beijing 100084

出　　处：《Chinese Physics Letters》2009年第7期177-180,共4页中国物理快报（英文版）

摘　　要：Dielectric gratings with period in the range from λ/10 to λ/4 with A being the illumination wavelength not only exclude higher order diffractions but also exhibit strong dispersion of effective indices which are proportional to the wavelength. Moreover, they are insensitive to the incident angle of the illumination wave. With these features, we can design a true zero-order achromatic and angle-insensitive phase retarder which can be used as the polarization state analyzer in middle wave infrared （MWIR） imaging polarimetry. A design method using effective medium theory is described, and the performance of the designed phase retarder is evaluated by rigorous coupled wave analysis theory. The calculation results demonstrate that the retardance deviates from 45° by 〈 ±1.6° within a field of view ：±l0° over the MWIR bandwidth （3-5μm）.Dielectric gratings with period in the range from λ/10 to λ/4 with A being the illumination wavelength not only exclude higher order diffractions but also exhibit strong dispersion of effective indices which are proportional to the wavelength. Moreover, they are insensitive to the incident angle of the illumination wave. With these features, we can design a true zero-order achromatic and angle-insensitive phase retarder which can be used as the polarization state analyzer in middle wave infrared （MWIR） imaging polarimetry. A design method using effective medium theory is described, and the performance of the designed phase retarder is evaluated by rigorous coupled wave analysis theory. The calculation results demonstrate that the retardance deviates from 45° by 〈 ±1.6° within a field of view ：±l0° over the MWIR bandwidth （3-5μm）.

分 类 号：TQ645.85[化学工程—精细化工] TP333.41[自动化与计算机技术—计算机系统结构]