| 摘要 |
PROBLEM TO BE SOLVED: To prevent the poorness in material yield and production efficiency and a high production cost thereof that are encountered heretofore in manufacturing a mirror blank of a rotary polyhedral mirror. SOLUTION: The method for manufacturing a polygonal planar member having a recessed part on at least either of front and rear surfaces and having a plurality of flat surfaces configurating a polygonal shape on its outer periphery has a step of preparing a polygonal planar blank having nearly the same outer peripheral contour shape as the outer peripheral contour shape of the polygonal planar member to be manufactured and having a board thickness thinner than the maximum board thickness of the polygonal planar member to be manufactured, a step of compressing at least either of the front and rear surfaces of the polygonal planar blank to the prescribed shape corresponding to the recessed part, fluidizing the remaining part of least either of the front and rear surfaces to a direction opposite to the compression direction and molding the front and rear surfaces and flat surfaces of the polygonal planar member. COPYRIGHT: (C)2004,JPO |
