Light receive scanner with liquid crystal beamsteerer

Patent metadata

Field	Value
Publication number	US-11681199-B2
Application number	US-201916543060-A
Country	US
Kind code	B2
Filing date	Aug 16, 2019
Priority date	Aug 16, 2019
Publication date	Jun 20, 2023
Grant date	Jun 20, 2023

Abstract

An optical system for receiving light scanned from different light origination locations in space can include a Liquid Crystal (LC) waveguide (LCW), including first and second LCW light ports. A beamsteering LC electrode can be included in or coupled to the LCW and can be configured to vary a receiving direction of light received at the second LCW light port in response to a varying electrical input signal applied to the LC electrode to scan receiving of light at the second LCW light port from different light origination locations in space. A photodetector can be optically coupled to the first LCW light port, such as to detect waveguided light from different light origination locations in space received in response to the varying electrical input signal applied to the first LC electrode. Ranger, bright-spot locking, laser detection, direct detect and coherent lidar, wavelength detection, and other techniques and use cases are possible.

First claim

The invention claimed is:

1. An optical system for receiving light scanned from different remote light origination locations in space, the optical system including:
a first Liquid Crystal (LC) waveguide (LCW), including first and second LCW light ports;
a beamsteering first LC electrode, included in or coupled to the first LCW, the first LC electrode configured to vary a receiving direction of light received at the second LCW light port in response to a varying electrical input signal applied to the first LC electrode to scan receiving of light at the second LCW light port from different remote light origination locations in space and to direct received light from different remote light origin locations in space through the LCW from the second LCW light port to the first LCW light port;
a photodetector, optically coupled to the first LCW light port, to detect waveguided light from different remote light origination locations in space at different locations of the photodetector by varying electrical input signal applied to the first LC electrode; and
a control circuit, configured to control the varying electrical input signal applied to the first LC electrode to direct receiving of waveguided light at the first LCW light port from different remote light origination target locations in space and to control the photodetector to direct the waveguided light from different remote light origin locations in space to different locations of the photodetector.

2. The optical system of claim 1 , in which the photodetector is integrated with the first LCW on a shared substrate.

3. The optical system of claim 2 , comprising a scanning region optical threshold comparator to compare to a threshold value an intensity of scanned received light at the second LCW light port from different remote light origination locations in space.

4. The optical system of claim 1 , in which an area of the second LCW light port is larger than an area of an input port of the photodetector, and wherein the first LCW waveguide tapers to concentrate light received at the first LCW light port and to direct the concentrated light to the input port of the photodetector.

5. The optical system of claim 1 , further comprising:
a second LCW, configured to receive input laser light at a third LCW light port and to guide and transmit the received input laser light out a fourth LCW light port; and
a beamsteering second LC electrode, included in or coupled to the second LCW, the second LC electrode configured to vary a transmitting direction of light transmitted at the fourth LCW light port in response to a varying electrical input signal applied to the second LC electrode to scan transmitting of light at the fourth LCW light port toward different remote target locations in space.

6. The optical system of claim 5 , wherein the received light at the second LCW port includes reflected light that is reflected from light transmitted from the fourth LCW light port.

7. The optical system of claim 1 , further comprising:
a flashed light source; and
a control circuit, configured to control the varying electrical input signal applied to the first LC electrode to scan receiving of light at the first LCW light port from different remote light origination locations in space in synchronization with respect to one or more flashes of light from the flashed light source.

8. The optical system of claim 1 , wherein the first LCW is configured to receive laser light input at the first LCW port, and further comprising:
a control circuit, configured to control the varying electrical input signal applied to the first LC electrode to scan transmitting of laser light received at the first LCW port and steered by the first LCW toward different remote target locations in space, and to receive at the second LCW port reflected light from the different remote target locations in space for being guided by the same first LCW toward the photodetector.

9. The optical system of claim 8 , including a light circulator configured to direct toward the photodetector, via the first LCW port, waveguided light received from the different remote target locations in space.

10. The optical system of claim 1 , in which the photodetector includes a pixelated photodetector including different pixels configured to receive and detect, via the first LCW port, different wavelengths of the waveguided light received from the different remote target locations in space.

11. The optical system of claim 1 , included in or in combination with a LIDAR system.

12. The optical system of claim 11 , in which the LIDAR system includes at least one of a direct detect LIDAR system or a coherent LIDAR system.

13. The optical system of claim 1 , further comprising signal processing circuitry configured to use the waveguided light received from the different remote target locations in space to a determine a range of at least one of the different remote target locations in space.

14. The optical system of claim 1 , further comprising control circuitry configured to control the varying electrical input signal applied to the first LC electrode to scan receiving of light at the first LCW light input port from different remote light origination locations in space for bright spot locking of at least one of the different remote target locations in space.

15. A method of receiving light scanned from different remote light origination locations in space, the method comprising:
receiving light at a second light port of a Liquid Crystal (LC) waveguide (LCW);
adjusting a control signal applied to a LC electrode of the LCW to scan receiving of light at the second LCW light port from different remote light origination locations in space; and
detecting waveguided light from a first light port of the LCW from the scanned different remote light origination locations in space, including controlling an electrical signal applied to a LC electrode near the first light port to steer waveguided light from scanned different remote light origin locations in space to different locations of a photodetector.

16. The method of claim 15 , comprising signal processing a signal based on the detected waveguided light to provide an indication associated with the different remote light origination locations in space.

17. The method of claim 16 , comprising using the indication for determining a range of at least one of the different remote light origination locations in space.

18. The method of claim 15 , further comprising detecting different wavelengths of the detected waveguided light received from at least one of the different remote light origination locations in space.

19. An optical system for receiving light scanned from different remote light origination locations in space, the optical system including:
a first Liquid Crystal (LC) waveguide (LCW), including first and second LCW light ports;
means for scanning receiving of light at the second LCW light port from different remote light origination locations in space, including a control circuit configured to control a varying electrical input signal applied to an incoupling LC electrode to scan receiving of light to scan the different remote light origin locations in space; and
means for detecting, at different locations of a photodetector, waveguided light from a first light port of the LCW from different remote light origination locations in space.

20. The system of claim 19 , comprising means for detecting different wavelengths of the detected waveguided light received from at least one of the different

Assignees

• Analog Devices Inc

Inventors

• Ziemkiewicz Michael
• Davis Scott Robert
• Anderson Michael Howard
• Sodergren Bennett
• Marathe Radhika

Classifications

• G02F2/004

  Transferring the modulation of modulated light, i.e. transferring the information from one optical carrier of a first wavelength to a second optical carrier of a second wavelength, e.g. all-optical wavelength converter · CPC title

• G02B6/00

  Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings · CPC title

• G02F1/011

  in optical waveguides, not otherwise provided for in this subclass · CPC title

• G02F1/313 Primary

  in an optical waveguide structure · CPC title

• G01S7/4817

  relating to scanning · CPC title