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Optical curve grinder is used to grind precision and complex surfaces, including straight lines, arcs, and curves. During the grinding process, the workpiece and grinding wheel can be magnified 50 times by an optical system and projected onto a screen. During work, the operator can observe the grinding wheel processing along the workpiece surface on the screen at any time. The movement of the workpiece can be manually operated or controlled by a DC motor to achieve the purpose of processing the surface.