| 摘要 |
PROBLEM TO BE SOLVED: To improve the performance of optical electronic equipment mounting an optical waveguide modulator or the like, by making at least one side edge part of an optical waveguide more built up than in the center part. SOLUTION: An optical IC chip is constituted by forming an optical waveguide of specified shape on an LiNbO3 substrate 2, and has a step difference 80 (step difference generated in association with the oxidation reaction of a Ti film) on the surface corresponding to a Ti diffusion part out of the surface of the LiNbO3 substrate 26. The height Ts of both side edge parts of the step difference 80 is made higher than the height Tc of the center part 80b so as to form the side edge parts 80a in more swollen shape than the center part 80b. Coupling loss of optical beams to an optical fiber with a different aspect ratio can thereby be reduced so as to eliminate the loss failure of an optical element and to reduce coupling loss to a polarization plane storage fiber used for optical parts of an optical waveguide modulator or the like. |
