Patent ID: 7302189

Claim:
An optical component including a device having two reflective surfaces which are opposed and parallel to each other, and provided with a demultiplexing function in which a light condensed in the one-dimensional direction is incident between the two reflective surfaces of said device, and a part of said incident light is transmitted through one of the two reflective surfaces while said incident light being multiple-reflected on the reflective surfaces, to be emitted, and said emitted light interferes mutually, so that optical beams, traveling directions of which are different from each other according to wavelengths, are formed, wherein said device includes: a first side surface substantially perpendicular to each of the reflective surfaces; and a second side surface opposed to said first side surface and tilted relative to a direction perpendicular to the two respective reflective surfaces, and said incident light is transmitted through said first side surfaces, and then, the transmitted light passes between the reflective surfaces to thereby be reflected by said second side surface, and the light reflected by said second side surface is multiple-reflected on the two respective reflective surfaces followed by being outputted from one of the two reflective surfaces, and then said outputted light is transmitted in a direction tilted toward said first side surface relative to a direction perpendicular to said one of the two reflective surfaces.