SEMICONDUCTOR OPTICAL MODULATION DEVICE

Abstract

A semiconductor optical modulation device includes a semiconductor optical modulator, an input terminal which is connected to a drive circuit for supplying an electrical signal to the semiconductor optical modulator, an output terminal which is connected to a terminating resistor, an input wire which connects the input terminal to an electrode of the semiconductor optical modulator, and an output wire which connects the output terminal to the electrode of the semiconductor optical modulator. In addition, an additional capacitor or an additional resistor is disposed between the input terminal and the output terminal, and connected in parallel with a series circuit including the input wire and the output wire.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an electrical circuit diagram showing a semiconductor optical modulation device according to a first embodiment of the present invention.

FIG. 2 is a Smith chart showing reflection characteristics of a conventional device obtained by removing the additional capacitor 8 from the circuit of FIG. 1 for comparison.

FIG. 3 is a Smith chart showing reflection characteristics of the first embodiment.

FIG. 4 is an electrical circuit diagram showing a semiconductor optical modulation device according to a second embodiment of the present invention.

FIG. 5 is a Smith chart showing reflection characteristics of the second embodiment.

FIG. 6 is an electrical circuit diagram showing a semiconductor optical modulation device according to a third embodiment of the present invention.

FIG. 7 is a Smith chart showing reflection characteristics of the third embodiment.

FIG. 8 is a top view of a semiconductor optical modulation device according to a fourth embodiment of the present invention.

FIG. 9 shows a top view of a semiconductor optical modulation device according to a fifth embodiment of the present invention.

FIG. 10 shows a top view of a semiconductor optical modulation device according to a sixth embodiment of the present invention.

FIG. 11 shows a top view of a semiconductor optical modulation device according to a seventh embodiment of the present invention.

FIG. 12 is a Smith chart showing reflection characteristics of the seventh embodiment.

FIG. 13 shows a top view of a semiconductor optical modulation device according to an eighth embodiment of the present invention.

FIG. 14 shows a top view of a semiconductor optical modulation device according to a ninth embodiment of the present invention.

FIG. 15 is a bottom view of the internal transmission line 60A in the ninth embodiment.

Claims

1. A semiconductor optical modulation device comprising: a semiconductor optical modulator having an electrode;an input terminal for connection to an outside drive circuit for supplying an electrical signal to said semiconductor optical modulator;an output terminal;a terminating resistor connected to said output terminal;an input wire connecting said input terminal to said electrode Of said semiconductor optical modulator;an output wire connecting said output terminal to said electrode of said semiconductor optical modulator; andat least one of a capacitor and a resistor disposed between said input terminal and said output terminal, said at least one of a capacitor and a resistor being connected in parallel with a series circuit comprising said input wire and said output wire.

2. The semiconductor optical modulation device according to claim 1, including both of said capacitor and said resistor disposed between said input terminal and said output terminal and connected in parallel with said series circuit comprising said input wire and said output wire.

3. The semiconductor optical modulation device according to claim 1, comprising said capacitor and a circuit board for mounting said semiconductor optical modulatory; wherein said capacitor is an inter-pattern capacitance between a pair of conductive patterns on said circuit board.

4. The semiconductor optical modulation device according to claim 1, including said capacitor wherein said capacitor is a chip capacitor.

5. The semiconductor optical modulation device according to claim 1, including said resistor wherein said resistor is a thin film resistor.

6. The semiconductor optical modulation device according to claim 1, including said resistor wherein said resistor is a chip resistor.

7. The semiconductor optical modulation device according to claim 1, further comprising a Peltier device and a transmission line having a conductive line, wherein said semiconductor optical modulator is mounted on said Peltier device and said output terminal is connected to said terminating resistor via said conductive line of said transmission line.

8. The semiconductor optical modulation device according to claim 7, wherein said transmission line includes a flexible baseboard.

9. The semiconductor optical modulation device according to claim 8, wherein said transmission line comprises a ground conductor having a lattice shape.