等周期变倾角干涉条纹复用法扩展增强现实耦合元件体光栅角度带宽  

Expanding the angular bandwidth of augmented reality coupling element volume holographic grating by multiplexing equal-period and variable-inclination-angle interference fringes

作　　者：彭灿福 李文昊[1] 张伟[1] 陈星硕 刘睿 张婧英 李文龙 PENG Can-fu;LI Wen-hao;ZHANG Wei;CHEN Xing-shuo;LIU Rui;ZHANG Jing-ying;LI Wen-long(Changchun Institute of Optics,Fine Mechanics and Physics,Chinese Academy of Sciences,Changchun 130033,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院长春光学精密机械与物理研究所,吉林长春130033 [2]中国科学院大学,北京100049

出　　处：《中国光学（中英文）》2023年第5期1157-1167,共11页Chinese Optics

基　　金：国家重点研发计划资助项目(No.2022YFF1202002);国家自然科学基金项目(No.62005270);中国科学院战略性先导科技专项(C类)资助(No.XDC04030100);吉林省科技发展计划项目(No.20210201140GX,No.20210402056GH);吉林省与中国科学院科技合作高技术产业化专项资金项目(No.2022SYHZ0024)。

摘　　要：为了提高光波导近眼显示成像系统的视场角,本文提出了一种等周期变倾角干涉条纹复用方法,用于扩展增强现实眼镜耦合元件体光栅的角度带宽。该方法通过复用等周期变倾角干涉条纹满足了不同入射角的布拉格条件,并且消除了体光栅周期变化对入射光衍射角度的影响,从而提升耦合元件体光栅的角度响应范围,降低光栅衍射引入的杂散光。利用严格耦合波理论对复用三幅等周期变倾角干涉条纹的体光栅进行模拟,在波长为530 nm的TE和TM偏振态下,复用后的体光栅角度带宽分别为3.6°和3.3°,与单幅干涉条纹体光栅相比,角度带宽扩展了1倍。该方法有望打破体光栅角度带宽受光栅材料的限制,用于扩展近眼显示成像系统的视场角,实现轻量化、高效率、大视场、低杂散光的增强现实眼镜。To improve the field of view of the near-to-eye display imaging system by using the optical waveguide scheme,we propose a method of multiplexing interference fringes with equal periods and variable inclination angles to expand the angular bandwidth of the volume holographic grating for augmented reality glasses coupling element.With this method,the range of incident angles after the expansion mathes the Bragg condition,and the influence of the periodic change on the diffraction angle of the incident light is eliminated,thereby improving the angular response range of the coupling element volume holographic grating and reducing the stray light introduced by grating diffraction.The rigorous coupled wave analysis theory is used to simulate the volume holographic grating multiplexing three interference fringes with equal period and variable inclination angles.Under the TE and TM polarization states at the wavelength of 530 nm,the angular bandwidth of the multiplexed volume holographic grating is 3.6°and 3.3°,respectively.The angular bandwidth of the multiplexed volume holographic grating is twice as large as that of the volume holographic grating recorded with a single interference fringe.This method is expected to break the limitation of the volume holographic grating material on the angular bandwidth of the grating,and can be used to expand the field of view of the near-to-eye display imaging system to achieve lightweight,high-efficiency,large-field-of-view,and low-stray-light augmented reality glasses.

关 键 词：增强现实 近眼显示 体光栅复用 角度带宽扩展 

分 类 号：O436[机械工程—光学工程]