title: Analysis and design of a concave diffraction grating with total-internal-reflection facets by a hybrid diffraction method.
abstract: A novel hybrid diffraction method is introduced to simulate the diffraction and imaging of a planar-integrated concave grating that has total internal reflection (TIR) facets. The Kirchhoff-Huygens diffraction formula is adopted to simulate the propagation of the lightwave field in the free-propagation region, and a rigorous coupled-wave analysis is used to calculate the polarization-dependent diffraction by the grating. The hybrid diffraction method can be used to analyze accurately the imaging properties as well as the polarization-dependent diffraction characteristics of a concave grating. The dependence of several merit parameters of a concave grating with TIR facets on its basic geometric parameters is studied. Compared with one with metallic echelle facets, a concave grating with TIR facets shows a much lower polarization-dependent loss. Since more performance specifications can be considered in the design of a concave grating than with the conventional scalar method, design error can be reduced greatly with the present hybrid diffraction method.
authors.affiliation: Centre for Optical and Electromagnetic Research, State Key Laboratory of Modern Optical Instrumentation, Zhejiang University, Yu-Quan, Hangzhou, 310027, China.
authors.forename: Zhimin
authors.initials: Z
authors.lastname: Shi
authors.forename: Jian-Jun
authors.initials: JJ
authors.lastname: He
authors.forename: Sailing
authors.initials: S
authors.lastname: He