PRODUCTION OF HALOGRAM DIFFRACTION GRATING

摘要

PURPOSE:To obtain stably a diffraction grating having high diffraction efficiency by coating positive type photoresist on a substrate to the specific film thickness with respect to the depth of the ruggedness of the diffraction grating to be formed. CONSTITUTION:Positive type photoresist is coated on a substrate 31 to the film thickness larger by >=0.15mum than the depth (h) of the ruggedness of the diffraction grating 33 to be formed on the substrate. For example, the resist is formed to about 0.6-2.0mum film thickness with respect to 0.35-1.2mum depth (h) of the ruggedness. The film thickness of the photoresist layer is controlled with respect to the depth (h) of the ruggedness of the grating 33 on the above-mentioned way by which the diffraction grating 33 having high diffraction efficiency is uniformly obtd. over the entire region of the pattern. The grating is widely used for a laser printer and various kinds of hologram-applying measuring instruments, etc.