Patent ID: 8078021
Filing Date: 2011-12-13
Classification: G02B

Abstract:
1. A waveguide connecting structure comprising: a light branching element which branches light from an input optical waveguide including one core into two branched light components having the same optical power and the same phase; and a twin-arm waveguide including a pair of arm waveguides which output the light components branched by said light branching element to a slot waveguide including two cores arranged in parallel at a narrow spacing, wherein said pair of arm waveguides have cores formed in a cladding on a substrate and having a refractive index higher than that of the cladding, and are formed such that a spacing between said pair of arm waveguides gradually narrows and becomes equal to a core spacing of said slot waveguide, from core input ends into which the branched light components enter toward core output ends from which the light components are output to said slot waveguide.