Patent ID: 7394950
Filing Date: 2008-07-01
Classification: G02F

Abstract:
1. An optical modulator of Mach-Zehnder type comprising: a substrate having a pair of optical waveguides formed therein; a signal electrode, formed on the substrate above one of the pair of optical waveguides, applying modulation signals that modulates light propagated over the optical waveguides; first and second earth electrodes, formed at either side of the signal electrode on the substrate, applying a ground potential, the first earth electrode being disposed above the other of the pair of optical waveguides; and a bias electrode, formed on the substrate adjacent to the first earth electrode on the opposite side of the signal electrode, applying a bias signal that controls an operation point for the modulation signal, wherein the thickness of the first earth electrode is greater than the thickness of the signal electrode, and the signal electrode, the first and second earth electrodes, and the bias electrode extend in parallel with one another along the optical waveguide.