Patent ID: 8559109

Claim:
A method for producing a diffraction optical element, wherein the diffraction optical element includes: a substrate formed of a first optical material containing a first resin and having a diffraction grating configuration at a surface thereof; and an optical adjusting layer formed of a second optical material containing a second resin and formed on the diffraction grating configuration of the substrate; the method comprising the steps of: positionally aligning a center of a molding face of a mold and a center of the diffraction grating configuration of the substrate, based on a marker of a prescribed shape which is formed at the center of the molding face of the mold and the diffraction grating configuration of the substrate; locating a starting material of the second optical material between the molding face of the mold and the diffraction grating configuration of the substrate; and pressing the starting material of the second optical material by the mold and the substrate to form the optical adjusting layer on the diffraction grating configuration; wherein the step of positionally aligning includes the step of positionally aligning the center of the diffraction grating configuration found based on a plurality of pairs of coordinates on the diffraction grating configuration and the marker.