WAVEGUIDE TYPE OPTICAL CIRCUIT

摘要

PROBLEM TO BE SOLVED: To provide a guide type optical circuit in which a deflection dependency is reduced or eliminated by reducing or eliminating birefringence. SOLUTION: A core structure is made into a multilayered structure formed by two or more kinds of layers having different refractive indexes. The birefringence of a waveguide can be decreased or eliminated when structural birefringence caused by the multilayered structure and the other birefringence among the birefringences of the waveguide cancel each other. For example, a silicon substrate is used for a substrate 501, a clad 502 and a core 503 are formed of silica glass, and the core 503 is made into the multilayered structure in which a plurality of first and second core layers 503a and 503b are alternately stacked.