Modulated light source

Patent metadata

Field	Value
Publication number	US-9537289-B1
Application number	US-201615146215-A
Country	US
Kind code	B1
Filing date	May 4, 2016
Priority date	Jun 30, 2015
Publication date	Jan 3, 2017
Grant date	Jan 3, 2017

Abstract

A modulated light source includes a ring modulator, a first optical waveguide and a second optical waveguide that are optically connected to the ring modulator, and a third optical waveguide that optically connects an end of the first optical waveguide and an end of the second optical waveguide. At least part of the third optical waveguide has optical gain, and an optical waveguide loop including the ring modulator, the first optical waveguide, the second optical waveguide, and the third optical waveguide is used as a resonator to cause laser oscillation.

First claim

What is claimed is:

1. A modulated light source comprising:
a ring modulator;
a first optical waveguide and a second optical waveguide that are optically connected to the ring modulator; and
a third optical waveguide that optically connects an end of the first optical waveguide and an end of the second optical waveguide,
wherein at least part of the third optical waveguide has optical gain, and
an optical waveguide loop including the ring modulator, the first optical waveguide, the second optical waveguide, and the third optical waveguide is used as a resonator to cause laser oscillation.

2. The modulated light source according to claim 1 , wherein a transmission wavelength band between the end of the first optical waveguide and the end of the second optical waveguide has a size that allows selecting one of a plurality of longitudinal modes in which laser oscillation is possible to occur, and the laser oscillation occurs in a single longitudinal mode.

3. The modulated light source according to claim 1 ,
wherein the first optical waveguide has another end having a mirror, and
the second optical waveguide has another end serving as a light output port.

4. The modulated light source according to claim 1 , including a plurality of optical waveguide loops each identical to the optical waveguide loop,
wherein in two adjacent optical waveguide loops out of the optical waveguide loops, another end of the second optical waveguide of one of the two adjacent optical waveguide loops and an end of the first optical waveguide of the other of the two adjacent optical waveguide loops are connected directly to each other.

5. The modulated light source according to claim 4 , wherein the first optical waveguide has another end having a mirror and not being connected directly to any end of another optical waveguide, and
the second optical waveguide has another end serving as a light output port and not being connected directly to any end of another optical waveguide.

6. The modulated light source according to claim 1 , wherein the optical waveguide loop has a plurality of ring modulators each identical to the ring modulator, and
the first optical waveguide and the second optical waveguide are optically connected to the plurality of ring modulators.

7. The modulated light source according to claim 1 , further comprising a heater unit that heats the ring modulator.

Assignees

• Fujitsu Ltd
• Photonics Electronics Technology Res Ass

Inventors

• Akiyama Tomoyuki

Classifications

• H01S5/0261

  Non-optical elements, e.g. laser driver components, heaters (H01S5/0265 takes precedence) · CPC title

• H01S5/142 Primary

  which comprises an additional resonator · CPC title

• H01S5/06832

  Stabilising during amplitude modulation · CPC title

• H01S5/0265

  Intensity modulators (intra-cavity modulators H01S5/0625) · CPC title

• H01S5/125

  Distributed Bragg reflector [DBR] lasers · CPC title