Abstract: A three-dimensional imaging method includes: projecting structured light pattern on a reference plane and capturing a reference plane image of the reference plane to obtain a reference phase; projecting structured light pattern on a workpiece surface and capturing a workpiece surface image set of the workpiece surface to obtain a workpiece phase; obtaining a workpiece phase difference based on the difference between the reference phase and the workpiece phase; performing temporal binarization encoding on the workpiece surface image set to generate a coded image; detecting noise areas in the coded image; integrating the noise areas to establish a noise phase mask; filtering noises in the coded image according to the noise phase mask to generate a noise-filtered phase; compensating for the noise-filtered phase to restore the workpiece phase difference; and performing three-dimensional reconstructing on the restored workpiece phase difference to form a 3D point cloud of the workpiece surface.

Abstract: A calibration method of three-dimensional measurement system includes a projection device, a camera and a processor. The projection device projects structural light to a reference object including a first calibration surface and a second calibration surface. The camera photographs the reference object to obtain at least one reference object image. The processor performs decoding according to the at least one reference object image to obtain a plurality of pieces of phase data of the at least one reference object image. The processor computes a first phase corresponding to the first calibration surface and a second phase corresponding to the second calibration surface according to the phase data, calculates a surface phase difference between the first phase and the second phase, and computes according to the surface phase difference and a height of the second calibration surface relative to the first calibration surface to obtain a phase-height conversion parameter.

Abstract: A non-contact detection method for a nut is provided. The method includes the following steps. The nut is photographed to obtain a threaded hole image of the nut. A thread area comparison between the threaded hole image and a standard threaded hole image is performed. An area difference is obtained according to the result of the thread area comparison. Whether the nut is a good nut is determined according to the area difference.

Abstract: A calibration method of three-dimensional measurement system includes a projection device, a camera and a processor. The projection device projects structural light to a reference object including a first calibration surface and a second calibration surface. The camera photographs the reference object to obtain at least one reference object image. The processor performs decoding according to the at least one reference object image to obtain a plurality of pieces of phase data of the at least one reference object image. The processor computes a first phase corresponding to the first calibration surface and a second phase corresponding to the second calibration surface according to the phase data, calculates a surface phase difference between the first phase and the second phase, and computes according to the surface phase difference and a height of the second calibration surface relative to the first calibration surface to obtain a phase-height conversion parameter.