Phase valuation-based superposition coding phase unwrapping method

• Main Authors: LIU YINPING, LIU JIA, WU DI, LU CHANGQIU, QI JIAN, WEN JIE, YAN FEI, XIAO YUQIAN, YU QIANG
• Format: Patent
• Language: Chinese; English
• Published: 14.03.2023
• Subjects: MEASURING; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS; MEASURING LENGTH, THICKNESS OR SIMILAR LINEARDIMENSIONS; PHYSICS; TESTING

The invention discloses a superposition coding phase unwrapping method based on phase valuation in the technical field of optical measurement, and the method comprises the following steps: determining the pixel width W1 of each period in an image, and generating N-step phase shift fringes; designing superposition coding stripes with auxiliary phase unwrapping, and uniformly assigning values to each period of the superposition coding stripes to generate a black and white stripe image; the modulated projection fringes are collected and transmitted to a computer; wrapping phases are extracted, and order fringes k1 are extracted; the level k2 of the other group of stripes is determined by superposing the two-value stripes on the level k1; and performing phase unwrapping operation on the wrapped phase to obtain the absolute phase of the measured object. According to the method, in the order obtaining process, the step order can be obtained through digital superposition operation of coding stripes, the algorithm is