Patent ID: 8095016

Claim:
A bidirectional optical transmitting/receiving module, comprising: a light emitting element for performing simultaneous bidirectional communications with light of two wavelengths by using a single-core optical fiber; a bidirectional V letter-shaped optical waveguide which is formed on a substrate and coupled to the light emitting element; and a dielectric multilayer filter formed on a folded-structured end face of the V letter-shaped optical waveguide, the dielectric multilayer filter having a characteristic of reflecting transmitted light from the light emitting element and a characteristic of transmitting received light from outside, wherein the folded-structured end face of the V letter-shaped optical waveguide is disposed at a position receded to an inner side with respect to an end face of the substrate, the substrate has a step structure having a width formed by the folded-structured end face of the V letter-shaped optical wave guide and the end face of the substrate, the folded-structured end face of the V letter-shaped optical waveguide is formed smoothly by etching, the end face of the substrate is form by dicing at a position shifted from the folded-structured end face of the V letter-shaped optical waveguide by the width of the step structure, and the dielectric multilayer filter is formed on the folded-structured end face of the V letter-shaped optical waveguide and on the step structure of the substrate.