An optical system of 3D parameters measurement for specific area of a workpiece has been presented and discussed
in this paper. A number of the CCD image sensors are employed to construct the 3D coordinate system for the measured
area. The CCD image sensor of the monitoring target is used to lock the measured workpiece when it enters the field of
view. The other sensors, which are placed symmetrically beam scanners, measure the appearance of the workpiece and
the characteristic parameters. The paper established target image segmentation and the image feature extraction
algorithm to lock the target, based on the geometric similarity of objective characteristics, rapid locking the goal can be
realized. When line laser beam scan the tested workpiece, a number of images are extracted equal time interval and the overlapping images are processed to complete image reconstruction, and achieve the 3D image information. From the 3D coordinate reconstruction model, the 3D characteristic parameters of the tested workpiece are gained. The experimental results are provided in the paper.