1. Field of the Invention
The present invention relates to an optical modulation device.
2. Background Art
A conventional optical modulator for performing optical modulation on an electrical signal is known as disclosed in JP-A-11-183858. The optical modulator disclosed in JP-A-11-183858 is a traveling wave optical modulator (also called an LN modulator). The optical modulator disclosed in JP-A-11-183858 has an optical waveguide, a signal electrode and a transmitting circuit. The signal electrode is provided near the optical waveguide. The transmitting circuit transmits an electrical signal (specifically, a high frequency voltage) to the signal electrode. A termination resistor is provided on the output side of the signal electrode. In JP-A-11-183858, a characteristic impedance of the signal electrode is set to a value different from a resistance of the termination resistor. A reflected wave generated by the difference between the characteristic impedance and the resistance is used to prevent a reduction in a characteristic of the optical modulation in a high frequency band.
USPTO Backgrounds
USPTO Backgrounds