Optical coupler, beam splitter, and arrayed waveguide grating type optical wavelength division multiplexer

摘要

An optical coupler, a beam splitter, and an AWG, according to the present invention are each provided with a transition region for the attainment of a low loss and can effectively prevent the reflection of optical signals which occurs in the transition region. The optical coupler, beam splitter, and AWG, according to the present invention are each provided with a slab waveguide 55, plural waveguides 62₁, 62₂, . . . , 62₁₀ for the output of optical signals and further provided with plural waveguide paths 63 for connecting adjacent ones of the waveguides 62₁, 62₂, . . . , 62₁₀. The waveguide paths 63 adjacent with respect to each of the waveguides are positioned at different distances from the slab waveguide 55.