Patent ID: 8730449
Filing Date: 2014-05-20
Classification: G02B,G03B,G03F

Abstract:
1. An optical device comprising: a wavelength separation filter configured to separate incident light into light having a first wavelength and light having a second wavelength, wherein the wavelength separation filter comprises a blazed grating whose cross-sectional shape is a saw-tooth shape formed by arranging a plurality of grating elements along a predetermined direction, wherein the blazed grating is configured to have a first power on the light having the first wavelength, by gradually changing blaze angles of the plurality of grating elements along the predetermined direction in which the plurality of grating elements are arranged, and have a second positive power of condensing the light having the second wavelength, by gradually changing lengths of the plurality of grating elements along the predetermined direction in which the plurality of grating elements are arranged.