| 摘要 |
PROBLEM TO BE SOLVED: To provide a wavelength demultiplexing optical element capable of reflecting a single wavelength of light from an incident light having the plurality of wavelengths, and capable of preventing substantially completely a light of an unintended sideband wavelength being reflected. SOLUTION: This wavelength demultiplexing optical element of the present invention is laminated at least with a waveguide layer, and a top layer having a refractive index higher by 0.03 or more than that of the waveguide layer, and is provided with a large number of isotropic protrusions formed regularly with a fixed interval on a surface of the top layer, the protrusions formed respectively independently with the fixed interval on the surface of the top layer have a pattern comprising two kinds of protrusion patterns (pattern A, pattern B) different in areas and/or shapes, and having the adjacent protrusion patterns different each other, and is constituted to make constant a distance between the imaginary center line a imagined along a direction passed through the center of the optional pattern A and perpendicular to the top layer surface, and the imaginary center line b imagined along a direction passed through the center of the adjacent pattern B and perpendicular to the top layer surface. COPYRIGHT: (C)2009,JPO&INPIT |
