Transimpedance amplifier for Lidar system

Patent metadata

Field	Value
Publication number	US-11614543-B2
Application number	US-201916582494-A
Country	US
Kind code	B2
Filing date	Sep 25, 2019
Priority date	Oct 9, 2018
Publication date	Mar 28, 2023
Grant date	Mar 28, 2023

Abstract

A Lidar system, photonic chip and method of detecting an object. The photonic chip includes a laser and one or more photodetectors. The laser generates a transmitted light beam. The one or more photodetectors are receptive to a reflected light beam that is a reflection of the transmitted light beam from an object and generate an electrical signal as output in response to the reflected light beam signal. An amplifier is configured to amplify a signal related to the reflected light beam to amplify the output signal of the one or more photodetectors. A processor determines a parameter of the object from the amplified output signal.

First claim

What is claimed is:

1. A method of detecting an object, comprising:
generating a transmitted light beam at a laser of a photonic chip, wherein a leakage energy from a back end of the laser passes through an amplifier region of the laser;
directing the transmitted light beam from the photonic chip;
adjusting a bias voltage in the amplifier region to amplify the leakage energy in the amplifier region to obtain an amplified local oscillator beam;
receiving a reflected light beam at the photonic chip, the reflected light beam being a reflection of the transmitted light beam from the object;
coupling the amplified local oscillator beam with the reflected light beam to obtain an output signal at a photodetector receptive to the coupled amplified local oscillator beam and the reflected light beam;
amplifying the output signal at a signal amplifier; and
determining, at a processor, a parameter of the object using the amplified output signal.

2. The method of claim 1 , wherein amplifying the output signal further comprises amplifying, via an electronic amplifier, an electrical signal output by the photodetector receptive to the reflected light beam.

3. The method of claim 2 , wherein the electronic amplifier is an integrated component of the photonic chip.

4. The method of claim 2 , wherein the electronic amplifier is separate from the photonic chip.

5. A photonic chip, comprising:
a laser configured to generate a transmitted light beam, wherein a leakage energy passes from a back end of the laser through an amplifier region of the laser;
a controller configured to adjust a bias voltage in the amplifier region to amplify the leakage energy in the amplifier region to obtain an amplified local oscillator beam
a coupler configured to couple a reflected light beam received at the photonic chip and the amplified local oscillator beam to obtain a coupled signal, the reflected light beam being a reflection of the transmitted light beam from an object;
one or more photodetectors receptive to the coupled signal and operable to generate an electrical signal in response to the coupled signal; and
an amplifier configured to provide an amplified of electrical signal output by the one or more photodetectors.

6. The photonic chip of claim 5 , wherein the amplifier is configured to amplify a local oscillator beam that is coupled to the reflected light beam to form the optical signal received at the one or more photodetectors.

7. The photonic chip of claim 6 , wherein the amplifier region is an element of the laser of the photonic chip receptive to the leakage energy from the laser.

8. The photonic chip of claim 5 , wherein the amplifier is an electronic amplifier receptive to the electrical signal generated at the one or more photodetectors.

9. The photonic chip of claim 8 , wherein the electronic amplifier is an integrated component of the photonic chip.

10. A Lidar system, comprising:
a photonic chip comprising:
a laser configured to generate a transmitted light beam, wherein a leakage energy passes from a back end of the laser through amplifier region of the laser;
a controller configured to adjust a bias voltage in the amplifier region to amplify the leakage energy in the amplifier region to obtain an amplified local oscillator beam
a coupler configured to couple a reflected light beam received at the photonic chip and the amplified local oscillator beam to obtain a coupled signal, the reflected light beam being a reflection of the transmitted light beam from an object;

one or more photodetectors receptive to the coupled signal and operable to generate an electrical signal in response to the coupled signal; and
an amplifier configured to amplify the electrical signal of the one or more photodetectors; and
a processor configured to determine a parameter of the object from the amplified electrical signal.

11. The Lidar system of claim 10 , wherein the laser generates a local oscillator beam that couples to the reflected light beam to form the optical signal, and the amplifier region is configured to amplify the local oscillator beam.

12. The Lidar system of claim 11 , wherein the amplifier region is an element of the laser of the photonic chip receptive to the leakage energy from the laser.

13. The Lidar system of claim 10 , wherein the amplifier is an electronic amplifier receptive to the electrical signal generated at the one or more photodetectors.

14. The Lidar system of claim 13 , wherein the electronic amplifier is an integrated component of the photonic chip.

15. The Lidar system of claim 13 , wherein the electronic amplifier is a separate component from the photonic chip.

16. The Lidar system of claim 13 , wherein the processor is further configured to navigate a vehicle using the parameter of the object.

Assignees

• Gm Global Tech Operations Llc

Inventors

• Talty Timothy J
• Mulqueen Michael
• Li James Chingwei
• Elliott Ken R

Classifications

• G01S7/4861

  Circuits for detection, sampling, integration or read-out · CPC title

• G01S17/89 Primary

  for mapping or imaging · CPC title

• G01S17/42

  Simultaneous measurement of distance and other co-ordinates (indirect measurement G01S17/46) · CPC title

• G01S7/4865

  Time delay measurement, e.g. time-of-flight measurement, time of arrival measurement or determining the exact position of a peak (peak detection in noise, signal conditioning G01S7/487) · CPC title

• G01S17/34 Primary

  using transmission of continuous, frequency-modulated waves while heterodyning the received signal, or a signal derived therefrom, with a locally-generated signal related to the contemporaneously transmitted signal · CPC title