Research For 3D Reconstruction Of The Transparent Object By Direct Polarized Light Measurements

Three-dimensional reconstruction technology has always been a hot topic in the field of machine vision,and has a wide range of applications in the fields of industrial manufacturing,visual inspection and auxiliary medical instrument.For the many kinds of measured objects,the transparent object has always been the difficulty for 3D reconstruction.Due to the existence of reflection and refraction in the transmission process,it is influenced easily by the global light.The factors cause the traditional method can not achieve the 3D reconstruction of the transparent objects.Therefore,the research of three-dimensional reconstruction of transparent objects has important theoretical significance and practical value.This paper presents a transparent object reconstruction method based on the combination of polarization analyses and light path triangulation,can simultaneously extract radiometric cues and geometric cues during surface reconstruction.By the experimental method and theory,this paper sets up a hardware experiment system through LED area source,linear polarizer and CCD area image sensor.Based on the compilation of the Matlab software algorithm,firstly the polarization data is extracted from the polarization image as the radiometric information.By calculating the the degree of polarization,the normal vector of the measured surface could be obtained.Then the point cloud data of the measured surface is obtained by the normal vector and geometric cues in the system.Finally,the error analyses is processed according to the experimental results.In order to verify the performance of the method,a series of comparison experiments are designed for the thickness,the material and the radius of curvature of the measured objects.The error is visually showed by the RMS error distribution and the error map.The experimental results show the method has the rapid data processing speed for avoiding the iterative calculation.And it has the high reconstruction efficiency,also shows a good reconstruction performance.The accuracy of this method is obviously higher than that of polarization analyses and light path triangulation used alone,and the root mean square error can reach 0.2748 mm for the len of 354.17 mm curvature radius.