1.Xianyang Normal University;2.China Electronics Standardization Institute/Shenzhen CESI Information Technology Co., Ltd.
The key projects of the scientific research plan of Xianyang Normal University (XSYK21030)
Traditional phase shifting interferometry requires multiple interferograms, which requires high stability of the measurement equipment and slow phase extraction. A phase solution method of two-frame random phase shifting interferograms is proposed based on the special extremum feature of the interferogram. This method requires only two interferograms. The two interferograms with random phase shifting are processed separately by Gaussian high-pass filter to filter out their background, Then the phase shifting between the two interferograms is determined by a certain number of special extreme feature pixels in the interferogram. Finally, the phase of the interferogram is calculated according to the phase shifting phase extraction algorithm of the arc tangent function. The comparison results of simulation and actual measurement show that this method can obtain high-precision measurement phase through two random phase shifting interferograms, and can also greatly reduce the influence of measurement system errors on the phase solution results. For the 256í256 pixels interferogram of the eye part of the plaster model, the execution time is within 0.02s, which is faster for phase extraction.