Rapid phase-height mapping calibration method

Abstract

The invention discloses a rapid phase-height mapping calibration method. The method comprises the following steps: establishing a three-dimensional measurement system; using a Harris corner detectionalgorithm for detecting the difference value of pixel coordinate values of checkerboard specific points shot by a camera to adjust the optical axis of the CCD camera to be perpendicular to a referenceplane; respectively obtaining high-precision absolute phase values of the standard plane before and after rotation through a time phase unwrapping method based on period correction; carrying out two-dimensional identification on the mark points on the rotated standard plane by using a centroid method to obtain pixel coordinates, and searching the absolute phase value of the corresponding mark point in the absolute phase value data of the corresponding standard plane; and fitting a plurality of virtual planes by using the slope of the standard plane and the absolute phase value of the mark point before rotation, and optimizing and solving system parameters by using a least square method to complete phase-height calibration. According to the invention, the calibration speed of the three-dimensional measurement system is greatly improved, and the method has potential application prospect and practical value in the field of desktop three-dimensional scanners.

Description

technical field [0001] The invention relates to an optical three-dimensional measurement method, which belongs to the technical field of photoelectric detection. In particular, it relates to a fast phase-height mapping calibration method. Background technique [0002] Structured light 3D imaging technology has the advantages of high precision, high speed and non-contact measurement, and has been widely used in industrial inspection, quality control, 3D printing, cultural relics protection and other fields. With the industrialization and upgrading of my country's production structure, the demand for the accuracy of three-dimensional measurement of large structural parts is gradually increasing, and fast three-dimensional precision is inseparable from the processing and manufacturing, process equipment and product testing links of aerospace, large ships, automobile bodies and rail transit. Measure to ensure product quality. [0003] In phase measurement profilometry, the trad...

AI Technical Summary

Problems solved by technology

However, in the actual large field of view measurement, it is time-consuming to use the stage to move the standard plane multiple times and more cumulative errors will be generated during the process of moving the standard plane

At the same time, the multi-view point cloud splicing by using the rotary table parameter calibration can complete the three-dimensional measurement of the measured object. However, when the traditional calibration method of a displacement table and a standard plane is used to calibrate the measurement system, the calibration process is time-consuming and the equipment is not easy. Issues such as carryover and accumulation errors

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