| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical modulator having high speed, low driving voltage and low DC bias voltage. SOLUTION: The optical modulator comprises: a substrate 1 having an electrooptic effect; an optical waveguide 3 formed on the substrate 1 to guide light; a traveling-wave electrode 4 formed on one surface side of the substrate 1 and consisting of a center conductor 4a for applying a high frequency electric signal for modulating light and applying bias voltage and ground conductors 4b, 4c; a connector part 6 provided with a core 7 for applying the high frequency electric signal from an external electric circuit to the center conductor 4a; and an interaction part 25 which is an area for modulating the phase of light travel through the optical waveguide 3 by applying the high frequency electric signal and the bias to the traveling-wave electrode 4. Where, a developed substrate 20 on which at least a center conductor 21a is formed is arranged in the vicinity of the core 7 of the connector part 6 to which the high frequency electric signal is inputted and the length of the interaction part 25 for modulating the phase of light is set longer as compared with a case that the developed substrate 20 is not used. COPYRIGHT: (C)2007,JPO&INPIT |
