| 摘要 |
PROBLEM TO BE SOLVED: To provide a high-speed, low driving voltage and low bias voltage light modulator with excellent production yield. SOLUTION: The light modulator includes an optical waveguide formed on a substrate 1 having an electro-optical effect, a traveling wave electrode composed of a central conductor and a grounded conductor for a high-frequency electric signal, and a bias electrode composed of a central conductor 15a and a grounded conductor 15b for a bias voltage. The optical waveguide includes an interaction part for a high frequency electrical signal for modulating the phase of light by applying a high-frequency electric signal to the traveling wave electrode, and an interaction part for a bias for adjusting the phase of light by applying a bias voltage to the bias electrode. In the optical wave guide, the light modulator is composed of a nest type light waveguide having a child Mach-Zehnder optical waveguide on branched optical waveguides of a parent Mach-Zehnder optical waveguide, respectively, wherein the bias electrode is formed such that a bias voltage is applied along a Y-branch arm that constitutes the branched optical wave guides of the parent Mach-Zehnder light waveguide. COPYRIGHT: (C)2010,JPO&INPIT |
