Optical curve grinding machines are used to grind precise and complex profiles, including straight lines, arcs, and curves. Through the refraction of light to reflect the shape of the processing curve, the processing of high-precision parts of the groove, inside and outside r, the shape of complex and high size requirements of the tool, etc., in the grinding process, the workpiece, the grinding wheel can be magnified by the optical system 20 times or 50 times, projected on the screen, when working, the grinding wheel is observed on the screen at any time along the workpiece surface processing, and the workpiece diagram magnified 20 times or 50 times of the film magnification chart is compared, the visual amplifier is used to enlarge the projection magnified graphics again, and the processing situation is observed online. And can manually interrupt or compensate for the processing procedure (if there is a grinding wheel wear, material, feed and other factors can be compensated and changed in time), so as to achieve the sample processing profile and the film times the chart is consistent, after the processing can also be through the projection method to check the workpiece, intuitive and clear. Whether it is during or after processing, the deviation can be observed and corrected in time, and the quality of the processed sample can be known without additional inspection.