Color-coded grating crosstalk compensation method based on projection plane

• Main Authors: LIU FEI, YAN JIN, LUO HUIFANG, ZHANG SHENGMING, ZHANG YINNAN, WU MINGXIONG, WU GAOXU, WU YANXUE, YANG SHICHAO
• Format: Patent
• Language: Chinese; English
• Published: 24.12.2019
• Subjects: CALCULATING; COMPUTING; COUNTING; IMAGE DATA PROCESSING OR GENERATION, IN GENERAL; MEASURING; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS; MEASURING LENGTH, THICKNESS OR SIMILAR LINEARDIMENSIONS; PHYSICS; TESTING

The invention discloses a color-coded grating crosstalk compensation method based on a projection plane, and the method establishes an error lookup table err (up, vp) between a grayscale absolute phase and a color absolute phase based on a projection coordinate conversion formula by respectively projecting a traditional black-and-white grating and a color grating (horizontal and vertical directions) on a standard flat plate, projects the color grating on the object to be measured and unwraps the phase to obtain the absolute phase of the object, and obtains the phase after crosstalk compensation by looking for the compensation amount of the phase value of the corresponding point on the projection plane. Different from other color channel compensation methods, the method effectively suppresses and corrects the color crosstalk error by establishing an error lookup table and using point-to-point full gray value compensation on the projection plane. The method provided by the invention proposes a feasible crosstal