Optical circuit
AssigneeNTT, Inc.
InventorsTakahiko Shindo, Meishin Chin, Shigeru Kanazawa, Yasuhiko Nakanishi
Life of this patent
Estimating the term…
Abstract
The optical circuit of the present disclosure provides a new optical transmitter configuration that achieves both high output and high quality transmission characteristics regardless of variations at cleavage positions. The optical circuit of the present disclosure may be an optical transmitter having an AXEL configuration in which an EADFB laser and a semiconductor optical amplifier (SOA) are integrated. In a window structure portion of a chip emission edge face of the AXEL, a partially thickened bulk semiconductor layer is formed by a structure including a simulated mesa configured to be separated from an optical axis parallel to an optical axis of an emission optical waveguide.
Claims7
An optical circuit integrating a semiconductor laser and a semiconductor optical amplifier (SOA) on a substrate, the optical circuit comprising:
- a waveguide being optically connected to the SOA and terminating inside of the substrate from an edge face;
- and
- a window region through including a plurality of simulated mesas configured parallel to an optical axis from an end of the waveguide to the edge face and being buried by a bulk semiconductor except for the plurality of simulated mesas, each of the plurality of simulated mesas being separated from the optical axis by a distance M,
- wherein
- light emitted from the end of the waveguide propagates to the edge face,
- the edge face is a cleavage surface,
- the waveguide includes a bent waveguide portion having a bending angle θwg toward the terminal end, and the optical axis is an extension line of an optical axis of the bent waveguide portion, and
- the plurality of simulated mesas comprising:
- two simulated waveguides that are arranged on both sides of the optical axis;
- and
- a third simulated waveguide that is separated by a distance 2M from one simulated waveguide opposite to a bending of the bent waveguide portion of the two simulated waveguides and being parallel to the two simulated waveguides.
Dependencies are inferred from the claim text.