Study Of Array Stripe Contour Measurement Principle Of Laser Interference

In the last few years,with the development of optoelectronic information and computer technologies,three-dimensional(3D)profile measurement system has been widely used in the field of geological exploration,medical field,cultural relic protection and so on.The non-contact three-dimensional profile measurement system is based on an optical system which projects structured lights on a surface of an object,which is a non-contact technique.This three-dimensional measurement has the advantages of no damage,real-time and high accuracy.There are some defects in the existing three-dimensional profilometry.A 3D profilometry based on laser ranging has disadvantages of slow speed and high cost.Another optical triangulation based on incoherent light has disadvantage to be affected by the vibration and ambient light.According to the research status of three-dimensional measurement,this thesis presents a new profile measurement based on laser interference fringe array.The thesis focuses on the principle of the new prfilometry,image processing and 3D reconstruction.The principle of this topic projects a laser interferometric array onto an object surface,obtains modulated laser interferometric array image through a camera,extracts the interference fringe array skeleton and three dimensional coordinate information through image processing,and reconstructs 3D using OpenGL.The laser lock-in imaging is used to eliminate the influence of ambient light in the process of measurement.A Fourier transform of the laser interferometric array image processing and the band-pass filter are used to filter the image.By using a threshold method,interference fringe center skeleton is extracted.The experimental results of laser interferometric array in various image processing methods are given.In 3D profile reconstruction,by using Delaunay algorithm and BPLI algorithm of interference fringe skeleton to splice broken fringes,the 3D reconstruction is accomplished,so that the observation is more stereo feeling through three-dimensional information extraction in the array of interference for three-dimensional reconstruction of objects to be measured.At the end of this thesis,3D profile measurement system framework and flow are introduced.The hardware with their parameters and software are introduced in detail.Finally,in different types of laser as light source,experimental measuring results are carried out by projecting interference array onto the measured object surface and showing the laser stripe image skeleton extraction process array and three-dimensional profile reconstruction experiment results of laser interference.