High Reflection Based On Phase Measurement Deflection (PMD) Research On Mirror 3D Reconstruction Method

In this paper,the advantages of phase measuring deflectometry(PMD)detection speed,high sensitivity,non-contact and low cost are used to realize the three-dimensional reconstruction of highly reflective mirror objects.In order to solve the problem of blurring of deformation fringes captured by the measurement system,it is proposed An analysis method for defocusing and defocusing of spatial variation is presented.First,the hardware system is calibrated,and the internal parameters of the camera and the correspondence between the camera and the reference plane and the LCD display are determined.Then,the phase is expanded using a multi-frequency heterodyne time solution phase.algorithm,and the deformation fringes are preprocessed to establish a space.Variable defocus blur model;finally,the purpose of blur stripe focusing is achieved through three-dimensional block matching algorithm(Block Matching 3D,BM3D),and experiments on circular and rectangular standard plane mirrors are carried out.The experimental results prove that the method in this paper can effectively improve deformation The amount of fringe fringes improves the accuracy of dephasing and mirror reconstruction.The research content and structural framework of this article mainly include the following aspects:1.The principle of phase measurement deflection is that the standard sinusoidal fringe is first generated by the computer and the fringe generated by the LCD display is simultaneously projected onto the research object to produce deformation.The detection system is calibrated using the Zhang Zhengyou calibration method,including camera calibration and LCD display calibration.As well as the calibration of the reference plane,the parameters of the measurement system are selected for subsequent experiments.2.The techniques of phase measurement wrapping and unwrapping phase are the research focus of this paper.First,the standard four-step phase shift is used to solve the wrapped phase through theoretical analysis,and the representative methods of the traditional time phase and spatial phase unwrapping algorithms are compared:Fourier change method and Multi-frequency heterodyne method is used to study the phase of single and multiple fringe patterns.For the preprocessing module of deformed fringes,the situation of local blur analysis caused by the limited depth of field of the industrial camera of the measuring system is first analyzed,and then the local fuzzy map corresponding to the spatial change of the deformed fringes is established,and the deconvolution algorithm is combined to obtain high-precision dephasing results;3.Combining the horizontal and vertical resolutions of the measurement system and the relationship between phase and gradient,through the analysis of the characteristics of the Fourier transform global integration method and the wavefront reconstruction algorithm based on the Southwell model area,the mathematical models of gradient and height are established respectively.The three-dimensional reconstruction of the rectangular plane mirror and the round mirror successively restores the three-dimensional shape,and analyzes the reconstruction errors:the error of the rectangular plane mirror is about,the error of the round plane mirror is about,and the error of the concave mirror is about.The final experiment verified this article The effectiveness and accuracy of the proposed method in the three-dimensional reconstruction of highly reflective mirror objects.