Low reflection diffraction grating and its production

Abstract

Abstract PURPOSE:To obtain the low reflection diffraction grating which is inexpensive and is highly reliable by providing a rugged structure having the periods smaller than the wavelengths of visible rays on the surface of the diffraction grating. CONSTITUTION:A copolymer consisting of an equal mole of methyl methacrylate and chloromethyl methacrylate, etc., is synthesized. Benzophenone is added to this copolymer at the mol equal to the mol of the chloromethyl methacrylate to prepare a 4wt.% benzene soln. and this soln. is applied on a glass substrate 21 to form a transparent photosensitive film 22. The film is exposed via. for example, a photomask 23 for the diffraction grating and is then subjected to two-beam interference exposing to bond the benzophenone to the chloromethyl methacrylate. Finally, the substrate is heated under a reduced pressure to sublimate the unreacted benzophenone, by which the diffraction grating 20 having the rugged surface is obtd. The low-reflection diffraction grating which is inexpensive and is highly reliable is thus obtd.

Inventors

• 👤 Katsuya Fujisawa
• 👤 藤沢　克也
• 👤 Masao Uetsuki
• 👤 植月　正雄

Bibliographic Details