Research Of 3D Deformation Measurement System Based On Laser Speckle Pattern Interferometry

Laser speckle pattern interferometry uses speckle as the carrier of information,it uses the relevant fringes of the interference speckle field generated by the measured object after being irradiated with laser light to detect the phase change between the front and rear of the two-beam wave.And it can perform full-field measurements of displacement,deformation,and strain.As a modern optical technology,laser speckle pattern interferometry has many advantages,such as simple structure,rapid measurement,accuracy,increasing use in the industrial field.In this paper,several key problems in speckle interferometry are analyzed.The main content includes:1.The principle of laser speckle pattern interferometry was described,and the development history and the status of the technology were also studied.2.The parameters of space carrier phase shifting technology were studied,and the influence of parameters on spectrum distribution was explored.From the aperture size,the angle of the incident light and the sampling frequency of the CCD camera,theoretical deduction and formula calculation were carried out,and the correctness of the calculation result was verified by experiments.3.The existing methods for measuring the mechanical properties of smooth surfaces were analyzed,and an improved digital speckle interferometry method was proposed.The principle of optical path and the key technologies were analyzed.4.The optical path design of the measurement system based on laser speckle pattern interferometry was completed,and a set of deformation detection instrument was set up.The in-plane and out-of-plane deformation measurement experiments were carried out by using the instrument.