| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical waveguide element module, which suppresses reflection of a modulating signal and suppresses attenuation of a modulating signal even when the impedance of a modulation electrode of the optical waveguide element differs from the impedance of a transmission line where a modulation signal is input from the outside of the optical waveguide element, and which can flatten the optical response frequency characteristics over a range as wide as several tens GHz even when a filter circuit including a capacitor is disposed on the line where a modulation signal is input to the modulation electrode of the optical waveguide element. SOLUTION: The module includes a relay line formed on a relay substrate 7 and connecting a connector 8, to which an external signal line is connected, to a modulation electrode 3, wherein the relay line is a coplanar line interposing a signal electrode with a ground electrode, and the impedance of the relay line is stepwisely or continuously changed so as to suppress reflection of a modulation signal in the optical waveguide element module. A filter circuit including a capacitor is disposed in the relay line. COPYRIGHT: (C)2011,JPO&INPIT |
