高边缘视场光学效率的衍射波导准直投影镜头设计  

Design of diffractive waveguide collimating lens with high optical efficiency in edge field

作　　者：黄战华[1,2] 高懿冰 伍圆军 潘成 芦畅泰 张尹馨[1] HUANG Zhanhua;GAO Yibing;WU Yuanjun;PAN Cheng;LU Changtai;ZHANG Yinxin(Key Laboratory of Opto-Electronics Information Technology(Ministry of Education),School of Precision Instrument and Opto-Electronic Engineering,Tianjin University,Tianjin 300072,China;Sichuan Innovation Research Institute,Tianjin University,Chengdu 610200,China)

机构地区：[1]天津大学精密仪器与光电子工程学院光电信息技术教育部重点实验室,天津300072 [2]天津大学四川创新研究院,四川成都610200

出　　处：《应用光学》2024年第1期54-62,78,共10页Journal of Applied Optics

摘　　要：随着微型发光二极管(micro-light emitting diode,Micro-LED)微型图像源被应用于增强现实(augmented reality,AR)显示技术,AR显示系统朝着超小型化方向发展。然而Micro-LED图像源发光角度大,准直投影镜头要求体积小且像质高,其产生的渐晕现象也导致视场(field of view,FOV)边缘处光学效率低、照度不均匀,这对AR光学系统设计造成了挑战。为了解决上述问题,该文基于增加计算得到的非球面场镜,设计了一种照度均匀性高、边缘视场光学效率较高的衍射光栅波导准直投影镜头。对场镜理论进行详细分析,从而确定焦距区间,最终求解其面型参数,设计出照度相对均匀的镜头。设计的新型准直投影镜头对角线FOV为41.2°,F#为1.87,调制传递函数在125 lp/mm处大于0.5。仿真结果表明,系统照度均匀性相对提高了14%,边缘FOV的光学效率相对提高了15%,具有良好的成像性能,该镜头可应用于超小型AR衍射光栅波导头戴显示系统中。Augmented reality(AR)display systems are developing towards ultra-miniaturization with the use of micro-light emitting diodes(Micro-LED)as miniature image sources in AR display technology.However,the Micro-LED with a large luminous angle,the collimating lens with a small size and high image quality,and the low optical efficiency at the edge of the field of view(FOV)and nonuniform illumination by vignetting of the collimating lens pose challenges for the design of AR optical systems.To solve these problems,a collimating lens was designed with high uniformity of illumination and high optical efficiency of the edge field of view for the diffraction grating waveguide by adding the calculated aspherical field lens.Then,by analyzing the theory in detail,its surface shape parameters were solved,and the lens with relatively uniform illumination was designed.The new collimating lens had a diagonal FOV of 41.2°,an F/#(F#)of 1.87,and a modulation transfer function greater than 0.5 at 125 lp/mm.The simulation results show that the illumination uniformity is relatively improved by 14%,and the optical efficiency of the edge FOV is relatively increased by 15%.The lens has good imaging performance,and can be applied in the ultra-small AR diffraction grating waveguide head-mounted display system.

关 键 词：准直投影镜头 光学效率 衍射光栅波导 光学设计 

分 类 号：TN202[电子电信—物理电子学]