Patent ID: 7149394

Claim:
A three-dimensional optical waveguide comprising: a plurality of cores that are disposed in a specified direction in at least two rows and at least two layers, each layer being disposed within a plane and being substantially parallel to each other; a cladding in which the cores are buried and having a refractive index different from that of the cores; a plurality of optical paths, each of which is formed within one of the layers by the cores; a first optical path converting device disposed at least at some of the cores and converting a direction of at least one of the optical paths to a direction different from the specified direction within the layer; and an inlet-outlet optical path that goes through the layers and intersects at least one of the cores and leads light into or out of the cores, a second optical path converting device converting the optical path direction of the at least one of the cores into the direction of the inlet-outlet optical path.