Patent ID: 11947237
Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 8:
9. The semiconductor Mach-Zehnder optical modulator according to claim 4, further comprising:
a first ground line along a propagation direction of the modulation signal on the dielectric layer outside the first input side lead-out line, the first phase modulation electrode line, and the first output side lead-out line; and
a second ground line along the propagation direction of the modulation signal on the dielectric layer outside the second input side lead-out line, the second phase modulation electrode line, and the second output side lead-out line, wherein:
the first and second output side lead-out lines are bent in a direction intersecting a direction in which the first and second arm waveguides extend in a plane of the dielectric layer and each have a line width shorter in a bent portion than in a straight portion in the direction perpendicular to the propagation direction of the modulation signal; and
the first and second ground lines are bent along the first and second output side lead-out lines and each have a shorter inter-line distance to a corresponding one of the first and second output side lead-out lines in the bent portion than in the straight portion.