光学学报, 2016, 36 (4): 0412003, 网络出版: 2016-04-05
点光源下的Talbot 效应在阴影叠栅中的应用
Shadow Moiré Using Talbot Effect Under Point Light Illumination
测量 光学三维测量 阴影叠栅轮廓术 菲涅耳-克希霍夫积分 Talbot效应 measurement optical three-dimensional measurement shadow Moiré profilometry Fresnel-Kirchhoff integral Talbot effect
摘要
传统的阴影叠栅轮廓术的测量深度十分有限。根据点光源照明下Talbot自成像的空间分布规律,提出将点光源下的Talbot效应应用于阴影叠栅三维轮廓测量的方法。推导点光源模型下阴影叠栅测量系统中相机接收到的光强随物体到光栅距离变化的数学表达式。数值模拟和实验表明,相对于传统的阴影叠栅轮廓术,利用Talbot效应会大大增加阴影叠栅轮廓术的测量深度。分别使用文中所提出的方法和传统的阴影叠栅轮廓术对同一物体表面进行测量,两次测量结果之差在±5 μm 内。说明将点光源下的Talbot效应应用于阴影叠栅轮廓测量能够准确地反映物体表面的三维形貌。
Abstract
The measurement depth of traditional shadow Moiré profilometry is very limited. According to the space distribution of Talbot self-imaging under the illumination of point light source, a new technique using Talbot effect under point light illumination for shadow Moiré profilometry is proposed. An exact mathematical formula describing the relationship between the intensity of shadow Moiré fringes under the point light illumination and the distance between measured object and gratings is derived. The numerical simulation and experiment show that the measurement depth of the shadow Moiré profilometry is increased notably by using the Talbot effect compared with the traditional shadow Moiré profilometry. Respectively, the proposed method and the traditional shadow Moiré method are used to measure the surface of the same object, the difference of the results obtained by the two methods is within ±5 μm. Thus the validity of the proposed technique is proved. The proposed method can reflect the threedimensional morphology of object surface accurately.
艾永旭, 周翔, 杜虎兵, 郭家玉, 杨涛, 赵磊. 点光源下的Talbot 效应在阴影叠栅中的应用[J]. 光学学报, 2016, 36(4): 0412003. Ai Yongxu, Zhou Xiang, Du Hubing, Guo Jiayu, Yang Tao, Zhao Lei. Shadow Moiré Using Talbot Effect Under Point Light Illumination[J]. Acta Optica Sinica, 2016, 36(4): 0412003.