Planar Optical Waveguide Circuit

Abstract

The invention provides a planar optical waveguide circuit capable of preventing part of the input signal light that has not been combined in the waveguide and propagates as leaked light from interfering with the output signal. A planar optical waveguide circuit having an optical waveguide embedded in a cladding layer includes: a plurality of parallel output optical waveguides configured to emit light from a same end face; a groove having a reflective interface formed at an angle of +45 degrees relative to the output optical waveguides and configured to reflect leaked light propagating in the cladding layer; and a groove having a reflective interface formed at an angle of −45 degrees, the reflective interface formed at an angle of +45 degrees, the output optical waveguide, and the reflective interface formed at −45 degrees being arranged repeatedly in that order.

Dependencies are inferred from the claim text.