WAVELENGTH MULTIPLEXER/DEMULTIPLEXER, OPTICAL MODULE, AND SERVER USING SAME

摘要

The present invention relates to a wavelength multiplexer/demultiplexer as a device having a multiplexing function for bundling light of different wavelengths and a demultiplexing function for separating light of different wavelength in a transmitter and receiver for realizing an optical interconnection, and the purpose of the present invention is to provide a wavelength multiplexer/demultiplexer in which the characteristics do not vary with variations in operating temperature, and in which there is no need for a temperature adjustment function. In order to achieve this purpose, the present invention is a wavelength multiplexer/demultiplexer having a diffraction grating and a plurality of optical waveguides formed on a substrate, wherein at least one of the optical waveguides is a slab waveguide, and a core of the slab waveguide is configured from air. The core constituting the slab waveguide is held between parallel flat plates of metal or a dielectric multilayer film, and the diffraction grating is formed adjacent to the slab waveguide by etching silicon. The metal or dielectric multilayer film is furthermore formed on a surface of the diffraction grating. The diffraction grating has a curvature of radius 2R, and the optical waveguides and the slab waveguide are optically connected on a circle of radius R adjacent to a portion of the circle of radius 2R formed by the diffraction grating.