Patent ID: 6721485
Filing Date: 2004-04-13
Classification: G02B

Abstract:
An echelon diffraction grating which comprises a substrate and an organopolysiloxane film having a maximum thickness of 1 &mgr;m to 1 mm formed on the surface of the substrate, and said organopolysiloxane film having a plurality of steps having a predetermined height of 5 to 500 &mgr;m and a predetermined width of 1 to 500 &mgr;m, wherein the organopolysiloxane film contains dimethylsiloxane represented by the following chemical formula (1) and a phenylsiloxane represented by the following chemical formula (2) as essential ingredients:(CH3)2SiO2/2â€ƒâ€ƒ(1) PhSiO3/2â€ƒâ€ƒ(2) wherein Ph is a phenyl group or substituted phenyl group.