| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical modulator having high performance of optical modulation characteristics, less insertion loss, and an improved production yield. SOLUTION: The optical modulator includes a substrate 1 having an electro-optical effect, a traveling wave electrode composed of a center conductor and a grounding conductor and disposed above the substrate, and a ridge part comprising a concave formed by engraving at least a part of the substrate in a region where the intensity of an electric field of a high frequency electric signal propagating in the traveling wave electrode is high, wherein the ridge part comprises a ridge part for the center conductor having the center conductor formed in an upper part and a ridge part for the grounding conductor having the grounding conductor formed in an upper part, and an optical waveguide is formed in the ridge part for the center conductor. The concave is composed of at least a first concave 13b and a second concave 14b with different widths from each other, from the upper face to the lower face of the substrate, and the width of the second concave 14b is smaller than the width of the first concave 13b. COPYRIGHT: (C)2010,JPO&INPIT |
