Integrated multi-channel wavelength monitor

Patent metadata

Field	Value
Publication number	US-9369201-B2
Application number	US-201213453930-A
Country	US
Kind code	B2
Filing date	Apr 23, 2012
Priority date	Apr 23, 2012
Publication date	Jun 14, 2016
Grant date	Jun 14, 2016

Abstract

An optical-source monitor images and diffracts received optical signals using an optical device that has a reflective geometry. For example, the optical device may include a diffraction grating on a curved surface, such as an echelle grating. By imaging and diffracting the optical signals, the optical device may couple to the optical signals on different diffraction orders of the optical device (which have different carrier wavelengths) from input optical waveguides to corresponding output optical waveguides. Then, output power monitors may measure the output power levels of the optical signals, and control logic may provide wavelength control signals to optical sources that provide the optical signals based on measured output power levels.

First claim

What is claimed is:

1. An optical-source monitor, comprising:
an optical device, input optical waveguides, output optical waveguides, output power monitors, and control logic,
the input optical waveguides configured to convey optical signals having carrier wavelengths, wherein each of the input optical waveguides is configured to convey a plurality of carrier wavelengths simultaneously, and wherein each of the input optical waveguides is arranged to have a different incident angle so that center carrier wavelengths of all the input optical waveguides are diffracted into a same output optical waveguide, wherein corresponding side carrier wavelengths of all the input optical waveguides are diffracted into respective output optical waveguides,
wherein the optical device comprises a plurality of input ports, a plurality of output ports, and a reflective geometry, each of the input ports optically coupled to a corresponding input optical waveguide and configured to receive the optical signal for the corresponding input optical waveguide,
wherein, for each optical signal of the optical signals, the optical device images and diffracts the optical signal from the corresponding input port using the reflective geometry, and wherein, after imaging and diffracting the optical signal, the optical device optically couples the optical signal to a corresponding output port in the output ports on a different diffraction order of the optical device,
wherein each of the output ports is optically coupled to a corresponding output optical waveguide of the output optical waveguides, and wherein each of the output ports is configured to couple the corresponding optical signal to the output optical waveguide for the output port,
wherein the output optical waveguides are configured to convey the optical signals, wherein each of the output optical waveguides is configured to receive one carrier wavelength from each of the input optical waveguides.

2. The optical-source monitor of claim 1 , wherein an incidence angle associated with the diffraction order is different than a diffraction angle associated with the diffraction order.

3. The optical-source monitor of claim 1 , wherein the reflective geometry includes a diffraction grating on a curved surface.

4. The optical-source monitor of claim 1 , wherein the reflective geometry includes an echelle grating.

5. The optical-source monitor of claim 1 , further comprising:
a substrate;
a buried-oxide layer disposed on the substrate; and
a semiconductor layer disposed on the buried-oxide layer, wherein the optical device is included in the semiconductor layer.

6. The optical-source monitor of claim 5 , wherein the substrate, the buried-oxide layer and the semiconductor layer comprise a silicon-on-insulator technology.

7. The optical-source monitor of claim 1 , wherein the carrier wavelengths have a fixed spacing.

8. The optical-source monitor of claim 1 , wherein a number of input optical waveguides equals a number of output optical waveguides; and
wherein the number of input optical waveguides equals a number of carrier wavelengths.

9. The optical-source monitor of claim 1 , wherein the output power monitors are optically coupled to the output optical waveguides and are configured to measure output power levels of the optical signals, wherein a given output power monitor is configured to measure an output power level of the given optical signal, and
wherein the control logic is electrically coupled to the output power monitors and is configured to provide wavelength control signals to optical sources that provide the optical signals based on the measured output power levels of the optical signals.

10. The optical-source monitor of claim 1 , further comprising:
beam splitters optically coupled to the input optical waveguides; and
input power monitors optically coupled to the beam splitters, wherein a given input power monitor is configured to measure an input power level of the given optical signal; and
wherein the control logic is electrically coupled to the input power monitors and is configured to provide power control signals to the optical sources that provide the optical signals based on measured input power levels of the optical signals.

11. A system, comprising:
a processor;
a memory storing a program module that is configured to be executed by the processor;
optical sources configured to output optical signals having carrier wavelengths, wherein a given optical signal output by a given optical source has a given carrier wavelength; and
an optical-source monitor, wherein the optical-source monitor which includes an optical device, input optical waveguides, output optical waveguides, output power monitors, and control logic,
the input optical waveguides configured to convey the optical signals, wherein each of the input optical waveguides is configured to convey a plurality of carrier wavelengths simultaneously, and wherein each of the input optical waveguides is arranged to have a different incident angle so that center carrier wavelengths of all the input optical waveguides are diffracted into a same output optical waveguide, wherein corresponding side carrier wavelengths of all the input optical waveguides are diffracted into respective output optical waveguides,
wherein the optical device comprises a plurality of input ports, a plurality of output ports, and a reflective geometry, wherein each of the input ports is optically coupled to a corresponding input optical waveguide and is configured to receive the optical signal for the corresponding input optical waveguide,
wherein, for each optical signal of the optical signals, the optical device images and diffracts the optical signal from the corresponding input port using the reflective geometry, and wherein, after imaging and diffracting the optical signal, the optical device optically couples the optical signal to a corresponding output port in the output ports on a different diffraction order or the optical device,
wherein each of the output ports is optically coupled to a corresponding output optical waveguide of the output optical waveguides, and wherein each of the output ports is configured to couple the corresponding optical signal to the output optical waveguide for the output port,
wherein the output optical waveguides are configured to convey the optical signals, wherein each of the output optical waveguides is configured to receive one carrier wavelength from each of the input optical waveguides.

12. The system of claim 11 , wherein an incidence angle associated with the given diffraction order is different than a diffraction angle associated with the given diffraction order.

13. The system of claim 11 , wherein the optical device includes a diffraction grating on a curved surface.

14. The system of claim 11 , wherein the optical device includes an echelle grating.

15. The system of claim 11 , further comprising:
a substrate;
a buried-oxide layer disposed on the substrate; and
a semiconductor layer is disposed on the buried-oxide layer, wherein the optical device is included in the semiconductor layer.

16. The system of claim 11 , wherein a number of input optical waveguides equals a number of output optical waveguides; and
wherein the number of input optical waveguides equals a number of carrier wavelengths.

17. The system of claim 11 , wherein the output power monitors are optically coupled to the output optical waveguides are configured to measure output power levels of the optical signals, wherein a given output power monitor is configured to measure a

Assignees

• Luo Ying L
• Zheng Xuezhe
• Krishnamoorthy Ashok V
• Li Guoliang
• Oracle Int Corp

Inventors

• Luo Ying L
• Zheng Xuezhe
• Krishnamoorthy Ashok V
• Li Guoliang

Classifications

• H01S5/0687

  Stabilising the frequency of the laser · CPC title

• H04B10/07955 Primary

  Monitoring or measuring power · CPC title

• H01S5/40

  Arrangement of two or more semiconductor lasers, not provided for in groups H01S5/02 - H01S5/30 (H01S5/50 takes precedence) · CPC title

• H04B10/0775 Primary

  Performance monitoring and measurement of transmission parameters · CPC title