| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical modulator that can reliably perform separation into signal light and radiation light. SOLUTION: The optical modulator includes a substrate 1 having an electro-optical effect; optical waveguides (2 to 4) formed on the substrate; and a modulating electrode for modulating a lightwave propagating the optical waveguides. The optical waveguide has at least a multiplexing part 3 for multiplexing the lightwave propagating the plurality of the optical waveguides 2; and an output waveguide 4 guided from the multiplexing part to an end portion of the substrate; two radiation light beams 5, emitted from the multiplexing part, are guided to the substrate end portion 10 by a slab waveguide or three-dimensional waveguide; in the output waveguide 4, the radiation light emitted from the multiplexing part crosses an optical path to the substrate end portion 10; an end portion of the output waveguide is arranged on the outside of the two radiation light beams in the substrate end portion; and the angle of a smaller side, among intersection angles formed by the output waveguide and radiation light, is≥3°. COPYRIGHT: (C)2011,JPO&INPIT |
