| 摘要 |
PROBLEM TO BE SOLVED: To provide a compact optical modulator outputting synchronized modulation light rays with low noise at a wide band from a plurality of optical modulation units even when the plurality of optical modulation units are arranged in parallel on the same substrate, and the input ends of the signal electrodes of the optical modulation units are arranged on one side face of the substrate. SOLUTION: In the optical modulator, an intermediate substrate 40 is provided separate from a main substrate 10 on which the plurality of optical modulation units 20A and 20B are provided in parallel, and signal lines 41A and 41B corresponding to the optical modulation units are formed on the intermediate substrate 40. The signal lines 41A and 41B are connected to the corresponding signal electrodes 31A and 31B on the main substrate 10, and have electrical lengths that are different from each other. Furthermore, the propagation loss per unit length in the signal lines 41A and 41B is preferably less than the propagation loss per unit length in the signal electrodes 31A and 31B on the main substrate 10. COPYRIGHT: (C)2010,JPO&INPIT |
