基于离焦度解包裹的结构光三维测量方法  

Three-dimensional measurement method of structured light based on defocus unwrapping

作　　者：陈豪 李宏宁 赵海 杨鑫[1] 高雅孺 CHEN Hao;LI Hongning;ZHAO Hai;YANG Xin;GAO Yaru(School of Physics and Electronic Information,Yunnan Normal University,Kunming 650500,China)

机构地区：[1]云南师范大学物理与电子信息学院,云南昆明650500

出　　处：《光学技术》2024年第2期209-214,234,共7页Optical Technique

摘　　要：基于结构光相位解包裹三维测量方法由于其精度较高而有广泛应用,但由于相位在超出2π时会被折叠,导致传统的结构光三维重建时需要相位解包裹。相位测量轮廓术在不连续深度处的解包裹相位较为复杂。当被测物体表面存在较大的深度差或者是测量多个平面时,由于包裹相位范围为[0,2π],在不连续处计算的相位差中存在折叠了多个2π的问题,导致解包裹失效。相位测量轮廓术在此时无准确表达物体位置信息。针对此问题,提出了一种基于离焦度解包裹的结构光三维测量方法,采用24步相移法获取包裹相位,通过时间散焦分析法确定包裹相位2π的个数来辅助进行解包裹计算。搭建了相应平台进行了实验,对所提方法进行验证。实验表明,方法较好的解决了相位测量轮廓术在深度落差较大时不能准确表达物体位置的问题,该方法可以用于获得深度落差较大场景的深度信息以及细节信息。The 3Dmeasurement method based on phase unwrapping of structured light is widely used because of its high accuracy.However,the phase will be folded when the phase exceeds 2π,so the traditional 3Dreconstruction of structured light requires phase unwrapping.The unwrapping phase of phase measurement profilometry at discontinuous depth is complicated.When there is a large depth difference on the surface of the measured object or when multiple planes are measured,because the wrapping phase range is[0,2π],there is a problem of folding multiple 2πin the phase difference calculated at the discontinuity,resulting in unwrapping failure.Phase measurement profilometry can not accurately express the position information of the object at this time.A three-dimensional measurement method of structured light based on defocus unwrapping is proposed.The 24-step phase shift method is used to obtain the wrapping phase,and the number of wrapping phase 2πis determined by time defocusing method to assist the unwrapping calculation.A corresponding platform is built and experiments are carried out to verify the proposed method.Experiments show that the proposed method solves the problem that the phase measurement profilometry can not accurately express the position of the object when the depth drop is large.The method can be used to obtain the depth information and details of the scene with large depth drop.

关 键 词：相位测量轮廓术 时间散焦分析法 三维信息测量 相位解包裹 

分 类 号：O439[机械工程—光学工程]