Device comprising a ring optical resonator

Patent metadata

Field	Value
Publication number	US-11079232-B2
Application number	US-201916511152-A
Country	US
Kind code	B2
Filing date	Jul 15, 2019
Priority date	Jul 19, 2018
Publication date	Aug 3, 2021
Grant date	Aug 3, 2021

Abstract

A device includes an optical resonator having four ports including a first port, a second port, a third port, and a fourth port. A first electronic circuit is configured to calculate a first information representative of a power difference between optical signals supplied by two of the four ports. A method of operating a device is also disclosed.

First claim

What is claimed is:

1. A device comprising:
an optical resonator comprising a first port, a second port, a third port, and a fourth port;
a first electronic circuit configured to calculate a first information representative of a power difference between a second-port optical signal supplied by the second port and a third-port optical signal supplied by the third port, the second-port optical signal and the third-port optical signal originating from a laser source; and
a second electronic circuit configured to calculate a second information representative of a power difference between a first-port optical signal supplied by the first port and a fourth-port optical signal supplied by the fourth port, the first-port optical signal and the fourth-port optical signal originating from the laser source, the second information being used to control a resonance wavelength of the optical resonator so that the power difference between the first-port optical signal and the fourth-port optical signal is zero at a wavelength of the laser source.

2. The device of claim 1 , wherein the optical resonator comprises a first ring waveguide.

3. The device of claim 2 , wherein the optical resonator further comprises a second waveguide coupled to the first ring waveguide and linking the first port to the second port, and a third waveguide coupled to the first ring waveguide and linking the third port to the fourth port.

4. The device of claim 3 , wherein the device is configured so that a initial optical signal is supplied to the first port and a first part of the initial optical signal is transmitted to the second port by the second waveguide to produce the second-port optical signal and wherein a second part of the initial optical signal is transmitted to the third port by the first ring waveguide to produce the third-port optical signal.

5. The device of claim 1 , wherein the laser source is linked to the first port and the second port.

6. The device of claim 5 , wherein the laser source has a wavelength adjustable according to a laser control signal.

7. The device of claim 6 , wherein the second electronic circuit determines the laser control signal based on the second information.

8. The device of claim 7 , wherein the second electronic circuit is configured to determine the laser control signal so that the second information is representative of a zero difference.

9. The device of claim 1 , further comprising an optical modulator.

10. The device of claim 9 , wherein the optical modulator is configured so that optical signals supplied to the first and second ports are modulated at different frequencies.

11. The device of claim 1 , wherein the first electronic circuit is configured to determine an angular speed based on the first information.

12. A device comprising:
an optical resonator comprising a first port, a second port, a third port, and a fourth port;
a laser source linked to the first port and the second port;
a first electronic circuit configured to calculate a first information representative of a power difference between a second-port optical signal supplied by the second port and a third-port optical signal supplied by the third port, the second-port optical signal and the third-port optical signal originating from the laser source; and
a second electronic circuit configured to calculate a second information representative of a power difference between a first-port optical signal supplied by the first port and a fourth-port optical signal supplied by the fourth port, the first-port optical signal and the fourth-port optical signal originating from the laser source, the second information being used to control a resonance wavelength of the optical resonator so that the power difference between the first-port optical signal and the fourth-port optical signal is zero at a wavelength of the laser source.

13. The device of claim 12 , wherein the optical resonator comprises:
a first ring waveguide;
a second waveguide coupled to the first ring waveguide and linking the first port to the second port; and
a third waveguide coupled to the first ring waveguide and linking the third port to the fourth port.

14. The device of claim 13 , wherein the device is configured so that an initial optical signal is supplied to the first port by the laser source and a first part of the initial optical signal is transmitted to the second port by the second waveguide to produce the second-port optical signal and wherein a second part of the initial optical signal is transmitted to the third port by the first ring waveguide to produce the third-port optical signal.

15. The device of claim 12 , wherein the laser source has a wavelength adjustable according to a control signal wherein the second electronic circuit is configured to determine the control signal based on the second information.

16. The device of claim 15 , wherein the second electronic circuit is configured to determine the control signal so that the second information is representative of a zero difference.

17. A method for determining a rotation speed of a device that includes an optical resonator comprising a first port, a second port, a third port, and a fourth port, the method comprising:
transmitting an initial optical signal from a laser source to the first port;
directing a first part of the initial optical signal to the third port via a first ring waveguide to produce a third-port optical signal;
directing a second part of the initial optical signal to the second port via a second waveguide to produce a second-port optical signal;
calculating a first information representative of a power difference between the second-port optical signal and the third-port optical signal;
determining the rotation speed of the device with respect to a central axis of the first ring waveguide based on the first information transmitting a second initial optical signal from the laser source to the second port;
directing a first part of the second initial optical signal to the fourth port via the first ring waveguide to produce a fourth-port optical signal;
directing a second part of the second initial optical signal to the first port via the second waveguide to produce a first-port optical signal; and
calculating a second information representative of a power difference between the fourth-port optical signal and the first-port optical signal; and
using the second information to control a resonance wavelength of the optical resonator so that the power difference between the first-port optical signal and the fourth-port optical signal is zero at a wavelength of the laser source.

18. The method of claim 17 , further comprising determining an angular speed based on the first information.

19. A device comprising:
an optical resonator comprising:
a first port being configured to receive an initial optical signal from a laser source and direct a first part of the initial optical signal to a third port via a first ring waveguide to produce a third-port signal and direct a second part of the initial optical signal to a second port via a second waveguide to produce a second-port signal;
the second port being configured to receive a second initial optical signal from the laser source and direct a first part of the second initial optical signal to a fourth port via the first ring waveguide to produce a fourth-port signal and direct a second part of the second initial optical signal to the first port via the second waveguide to produce a first-port signal; and

a first electronic circuit configured to calculate a f

Assignees

• St Microelectronics Srl

Inventors

• Fincato Antonio
• Temporiti Milani Enrico Stefano
• Zuffada Maurizio
• Simbula Angelica

Classifications

• G01C19/727 Primary

  using a passive ring resonator · CPC title

• G01C19/662 Primary

  signal readout; dither compensators · CPC title