Directly modulated laser with integrated optical filter

• US 7,778,552 B2
• Filed: 03/02/2006
• Issued: 08/17/2010
• Est. Priority Date: 03/02/2006
• Status: Active Grant

• Current Assignee: II-VI Delaware, Inc. (Coherent Corp.)
• Original Assignee: Finisar Corporation (II-VI Incorporated)
• Inventors: Deng, Hongyu, Vandyshev, Yuri
• Primary Examiner(s): Phan; Hanh
• Application Number:
  US11/366,329
• Publication Number:
  US 20100172650A1
• Time in Patent Office: 1,629 Days
• Field of Search: 398/182, 398/183, 398/185, 398/186, 398/187, 398/192, 398/193, 398/194, 398/195, 398/196, 398/197, 398/198, 398/199, 398/200, 398/201, 398/135, 398/136, 398/137, 398/138, 398/139, 398/79, 398/82, 398/84, 398/85, 398/87, 385/24, 385/37, 385/27, 385/35, 385/15, 385/33, 385/39, 372/50, 372/96, 372/97, 372/101, 372/106, 372/20, 372/92, 372/6, 372/102
• US Class Current: 398/183
• CPC Class Codes: H04B 10/504 using direct modulation
• CPC Class Codes: H04B 10/54 Intensity modulation
• CPC Class Codes: H04B 10/548 Phase or frequency modulation

Abstract

An integrated optical source includes a Directly Modulated Laser (DML) and a filter which is positioned with the DML on a common substrate. The filter is configured to receive an input signal in the form of a modulated chirped optical signal. The filter is further configured to provide an output optical signal in the form of an amplitude and/or phase modulated optical signal, optimized for long-distance transmission in optical fiber.

Claims

1. An integrated optical source comprising:

a substrate;

a Direct Modulated Laser (DML) supported by the substrate; and

an active current-tunable filter supported by the substrate and located proximate the DML, where an input to the filter comprises a modulated chirped optical data signal, and a corresponding output of the filter comprises at least one of an amplitude modulated optical data signal, a phase modulated optical data signal, or an optical data signal that incorporates both amplitude and phase modulation, the filter being tunable by a bias current applied thereto.

2. An optical source in accordance with claim 1, wherein the filter comprises:

a back mirror section;

a front mirror section; and

a cavity spacer region interposed between the front and back mirror sections.

3. An optical source in accordance with claim 1, wherein the filter comprises a tunable filter such that a change in the input modulated optical data signal corresponds to a change in a predetermined characteristic of the filter.

4. An optical source in accordance with claim 1, wherein the filter and DML are separated by an air gap.

5. An optical source in accordance with claim 1, wherein the filter and DML are in contact with each other.

6. An optical source in accordance with claim 1, wherein the filter has about a 3 db bandwidth of about 10 GHz.

7. An optical source in accordance with claim 1, wherein the filter includes a filter contact configured to receive and conduct the bias current.

8. An optical source in accordance with claim 1, wherein the directly modulated laser is one of a Fabry-Perot (FP) laser, a Distributed Feedback laser (DFB), or a Distributed Bragg Reflection laser (DBR).

9. An optical source in accordance with claim 1, wherein the filter and DML are substantially spectrally matched with each other at an operating temperature of the optical source.

10. An optical source in accordance with claim 1, wherein the filter comprises a distributed Bragg reflector.

11. An optical source in accordance with claim 1, wherein the DML is an edge-emitting laser.

12. A transmitter optical subassembly (TOSA), comprising:

a substrate;

a DML supported by the substrate;

an active current-tunable filter supported by the substrate and located proximate the DML, where an input to the filter comprises a modulated chirped optical data signal, and a corresponding output of the filter comprises at least one of an amplitude modulation optical data signal, a phase modulation optical data signal, or an optical data signal that incorporates both amplitude and phase modulation, the filter being tunable by a bias current applied thereto;

a transmit node coupled to the filter and configured to pass an optical signal to an optical fiber; and

a connection node coupled to the DML and configured to receive one or more electrical signals.

13. A TOSA in accordance with claim 12, wherein the filter comprises:

a back mirror section;

a front mirror section; and

a lasing cavity spacer region interposed between the front and back mirror sections.

14. A TOSA in accordance with claim 12, wherein the filter comprises a tunable filter such that a change in the input modulated optical data signal corresponds to a change in a predetermined characteristic of the filter.

15. A TOSA in accordance with claim 12, wherein the filter includes a cavity formed in a light propagation direction.

16. A TOSA in accordance with claim 12, wherein the filter and DML are substantially spectrally matched with each other during operation of the optical source.

17. A TOSA in accordance with claim 12, wherein the filter has about a 3 dB bandwidth of about 10 GHz.

18. A TOSA in accordance with claim 12, wherein the filter comprises an integrated optical filter.

19. A TOSA in accordance with claim 12, wherein the directly modulated laser is one of a Fabry-Perot (FP) laser, a Distributed Feedback laser (DFB), or a Distributed Bragg Reflection lasers (DBR).

20. An optical transceiver comprising:

a Receiver Optical Subassembly (ROSA) configured to receive an optical signal and generate a corresponding electrical signal;

a post-amplifier configured to process the electrical signal generated by the ROSA; and

a Transmitter Optical Subassembly (TOSA) configured to transmit an optical signal to an optical fiber, and the TOSA comprises;

a substrate;

a DML supported by the substrate; and

an active current-tunable filter supported by the substrate, where an input to the filter comprises a modulated chirped optical data signal, and a corresponding output of the filter comprises at least one of an amplitude modulation optical data signal, a phase modulation optical data signal, or an optical data signal that incorporates both amplitude and phase modulation, the filter being tunable by a bias current applied thereto; and

a laser driver configured to provide electrical signals to the TOSA.

21. An optical transceiver in accordance with claim 20, wherein the optical transceiver is one of a 1 Gb/s laser transceiver, a 2 Gb/s laser transceiver, a 4 Gb/s laser transceiver, a 8 Gb/s laser transceiver, or a 10 Gb/s laser transceiver.

22. An optical transceiver in accordance with claim 20, wherein the filter includes a cavity formed in a light propagation direction.

23. An optical transceiver in accordance with claim 20, wherein the optical transceiver substantially conforms with one of the following form factors;

XFP;

SFP;

SFF.

24. An optical transceiver in accordance with claim 20, wherein the directly modulated laser is one of a Fabry-Perot (FP) laser, a Distributed Feedback laser (DFB), or a Distributed Bragg Reflection lasers (DBR).

25. An optical transceiver in accordance with claim 20, wherein the filter comprises an integrated optical filter.