Optical module
An optical module providing higher reliability during high-speed light modulation and a lower bit error rate when built into a transmitter (transceiver). An optical module contains a taper mirror for surface emission of output light, an optical modulator device, and an optical modulation drive circuit, and the optical modulator device and the optical modulation drive circuit are mounted at positions so as to enclose the taper mirror.
1. An optical module comprising:
an optical device containing a taper mirror integrated onto an optical modulator device; and
a first drive circuit to modulate the optical modulator device,
wherein the optical modulator device and the first drive circuit are mounted at positions on the same optical axis, and the taper mirror is interposed between the optical modulator device and the first drive circuit, such that modulated light is emitted from the optical modulator device toward the first drive circuit, and
wherein the taper mirror reflects the modulated light such that the reflected modulated light propagates in a direction that is substantially perpendicular to a surface of a substrate over which the optical modulator device is mounted.
2. The optical module according to claim 1 ,
wherein, the optical device is any one among an EA (electro-absorption) modulator integrated DFB laser, an MZ (Mach-Zehnder) modulator integrated DFB laser, and an integrated device on which a light source, a modulator device, and a semiconductor optical amplifier are integrated.
3. The optical module according to claim 1 ,
wherein the substrate contains a step,
wherein the first drive circuit is mounted over a lower step surface of the substrate,
wherein the optical device is mounted over an upper step surface of the substrate, and
wherein a wire couples the first drive circuit to electrical wiring over the upper step surface of the substrate.
4. The optical module according to claim 1 ,
wherein the first drive circuit and the optical device are flip chip bonded over the same layer of the substrate.
5. The optical module according to claim 1 , further comprising:
a photo diode to monitor the output of the optical device, wherein the photo diode and the first drive circuit, which partially surround the optical device, are mounted at positions on the same optical axis.
6. The optical module according to claim 5 ,
wherein the light receiving surface of the photo diode is tilted towards the substrate surface where the optical device is mounted.
7. The optical module according to claim 1 ,
wherein the taper mirror, optical modulator device, and laser diode are integrated in that sequence in the optical device, and the optical module further includes a second drive circuit to supply direct current to the laser diode, and
wherein the second drive circuit and the taper mirror, which partially surround the laser diode, are mounted at positions on the same optical axis.
8. The optical module according to claim 7 ,
wherein the substrate contains a step section,
wherein the second drive circuit is mounted over a lower step surface of the substrate,
wherein the optical device is mounted over an upper step surface of the substrate, and
wherein a wire couples the second drive circuit to electrical wiring on the upper step surface of the substrate.
9. The optical module according to claim 7 ,
wherein the second drive circuit and the optical device are flip chip bonded over the same substrate.
10. The optical module according to claim 1 , wherein the taper mirror is the only optical component that is arranged between the optical modulator device and the first drive circuit.
11. The optical module according to claim 1 , further comprising:
a photo diode to monitor the output of the optical device, wherein the photo diode and the first drive circuit are mounted on opposite sides of the optical device.
12. The optical module according to claim 11 , wherein the photo diode and the first drive circuit are mounted at positions on the same optical axis.