增强现实光学系统虚像视场角测量方法  

Measurement Method of Virtual Field of View in Augmented Reality Optical Systems

作　　者：田方旭 张军[1] Tian Fangxu;Zhang Jun(Guangzhou Key Laboratory of Visible Light Communication,College of Science and Engineering,Jinan University,Guangzhou 510632,Guangdong,China)

机构地区：[1]暨南大学理工学院广州市可见光通信重点实验室,广东广州510632

出　　处：《激光与光电子学进展》2022年第20期176-182,共7页Laser & Optoelectronics Progress

基　　金：广东省重点领域研发项目(2020B090921002);广东省基础与应用基础研究基金(2021A1515011933)。

摘　　要：由于增强现实(AR)光学系统虚像视场角(VFOV)测量中存在测量方法、虚像边缘判断标准不明确的问题,开展了针对AR光学系统VFOV测量方法的研究。设计了基于摄影系统采集图像计算VFOV的方法,采集了不同虚像视距(VID)时AR镜片样品所显示的最大虚拟图像,然后分析了6类像素亮度统计参数以不同倍率作为视场边缘像素的亮度阈值、不同VID对VFOV测量结果的影响。结果表明:6类统计参数所得VFOV测量结果存在11°(V)×7°(H)的差别;同一亮度阈值不同VID下VFOV最大波动范围为±2.630°(V)×±1.685°(H),最小波动为±0.228°(V)×±0.360°(H)。因此判定边缘像素的亮度阈值与VFOV结果高度相关,VID对VFOV测量的影响远小于亮度阈值的影响。推荐采用像素亮度算术平均值的64%作为阈值,该方案所得的VFOV结果最稳定,相对波动仅为0.91%,所设计的测量方案为测量AR光学系统的VFOV提供了普适的测量方法和流程,具有一定指导意义。The virtual field of view(VFOV)is an important design parameter of augmented reality(AR)optical systems.The measurement method and the standard used to assess virtual image edges are not clearly established.A measurement method for determining the VFOV of an AR optical system is investigated in this study.First,the method is designed to calculate the VFOV of the AR optical system based on image acquisition by the camera system,and the maximum virtual image displayed by the AR lens sample at different virtual image view distances(VIDs)is acquired.Then,the effects of different pixel luminance statistical parameters as luminance thresholds in the determination of the virtual image edge and different VIDs on the VFOV measurement results are analyzed.The results show that there is a difference of 11°(V)×7°(H)in the VFOV measurements obtained for the six types of statistical parameters.Further,the maximum fluctuation range in VFOV for different VIDs at the same luminance threshold is found to be±2.630°(V)×±1.685°(H)and the minimum is±0.228°(V)×±0.360°(H).It is concluded that the luminance threshold of edge pixels is highly correlated with the VFOV results.The influence of the VID on the VFOV measurement is found to be significantly less than that of the luminance threshold.A threshold value of 64%of the arithmetic mean of the pixel luminance is used in this study as the VFOV results obtained with this value are the most stable,with a relative fluctuation of only 0.91%.The proposed measurement method and the process can be considered to be highly significant for AR optical systems.

关 键 词：增强现实光学系统 虚像视场角 虚像视距 虚像视场边缘判定方法 

分 类 号：O439[机械工程—光学工程]