Patent ID: 7286293
Filing Date: 2007-10-23
Classification: G02B,Y10S

Abstract:
1. A method for fabricating a diffractive optical element that comprises a first element and a second element, whose materials are different from each other and which elements are bonded to each other, with a diffraction grating created on a boundary surface between said first element and said second element, said method comprising: (a) forming said first element by steps including: (b) removing said first element from said die; and (c) forming said second element by steps including: wherein for forming said second element by use of said treating step to cure said photo-setting resin material with light rays passed through said first element, said first and second elements of said diffractive optical element are made of materials selected to satisfy a predetermined range of values including values that make a transmittance of said first element and a transmittance of said second element substantially equal to each other for said light rays, so that as differences in cure shrinkage of said photo-setting resin material are generated by differences in intensity of said light rays caused from ups and downs of said diffraction grating created on said surface of said first element, said differences in cure shrinkage are controlled within a range so as not to degrade a desired performance of said diffractive optical element.