DIFFRACTION OPTICAL ELEMENT, METAL MOLD FOR MOLDING DIFFRACTION OPTICAL ELEMENT, METHOD FOR MANUFACTURING DIFFRACTION OPTICAL ELEMENT, AND METHOD FOR MANUFACTURING METAL MOLD FOR MOLDING DIFFRACTION OPTICAL ELEMENT

摘要

PROBLEM TO BE SOLVED: To provide a diffraction optical element in a desired accurate diffraction grating shape having no burr at a grating peak, a metal mold for molding the diffraction optical element, a method for manufacturing the diffraction optical element, and a method for manufacturing the metal mold for molding the diffraction optical element.;SOLUTION: After a grating surface having an angle of ≤10° to a plane of a grating peak shape part is processed 11 and rough processing 12 is carried out to leave a designated distance to the grating surface, a tool cutting edge is moved on a straight line as a prolongation of the plane of the grating peak shape part from a cutting start position 13 to a position 14 at a designated distance to a grating surface side and then while the plane of the grating peak shape part is cut to a width of ≤10 μm, the tool cutting edge is moved to a position at a designated distance apart from a vertical plane and then moved from the cutting position to a point 16 where the grating peak is originally present before the grating peak is cut. Then the vertical plane is finished 18 while cutting up to the bottom part 17 of the vertical surface to complete processing wherein no burr is produced at a grating peak.;COPYRIGHT: (C)2007,JPO&INPIT