Lidar system and control system for a motor vehicle

Patent metadata

Field	Value
Publication number	US-11585938-B2
Application number	US-201916264128-A
Country	US
Kind code	B2
Filing date	Jan 31, 2019
Priority date	Feb 1, 2018
Publication date	Feb 21, 2023
Grant date	Feb 21, 2023

Abstract

A LIDAR system includes a monolithic frequency-stabilized semiconductor laser having a linear thermal wavelength shift and a bandpass filter that is configured to effectuate a thermal wavelength shift that does not deviate from the linear thermal wavelength shift of the semiconductor laser by more than 40%, and a temperature stabilization of the semiconductor laser can be dispensed with by the use of the invention. The LIDAR system can be provided in a control system that includes a control unit that controls obstacle avoidance of a motor vehicle based on an obstacle distance determined by the LIDAR system.

First claim

What is claimed is:

1. A LIDAR system comprising:
a monolithic frequency-stabilized semiconductor laser having a linear thermal wavelength shift;
a receiver configured to receive light that passes through an optical path to the receiver; and
a bandpass filter that:
is configured to effectuate a thermal wavelength shift that does not deviate from the linear thermal wavelength shift of the semiconductor laser by more than 40%; and
includes:
a plurality of filter segments whose transmission properties differ from one another; and
a shift element, wherein the shift element is configured to respond to change which of the plurality of filter segments is positioned in the optical path in dependence on changes in temperature.

2. The LIDAR system of claim 1 , wherein the bandpass filter includes an element made entirely or partially of a material for which a dependence of a central wavelength on temperature is significantly greater than that of glass.

3. The LIDAR system of claim 1 , wherein the bandpass filter includes an element made entirely or partially of a material for which a dependence of a central wavelength on temperature is at least two times greater than that of glass.

4. The LIDAR system of claim 1 , wherein respective layer thicknesses of the plurality of filter segments differ from one another.

5. The LIDAR system of claim 1 , wherein the thermal wavelength shift effectuated by the bandpass filter does not deviate by more than 0.01 nm/K from the linear thermal wavelength shift of the semiconductor laser.

6. The LIDAR system of claim 1 , wherein the thermal wavelength shift effectuated by the bandpass filter does not deviate by more than 20% from the linear thermal wavelength shift of the semiconductor laser.

7. The LIDAR system of claim 1 , wherein the thermal wavelength shift effectuated by the bandpass filter does not deviate by more than 5% from the linear thermal wavelength shift of the semiconductor laser.

8. A motor vehicle control system comprising:
a control unit; and
a LIDAR system that is configured to determine an obstacle distance and that includes:
a monolithic frequency-stabilized semiconductor laser having a linear thermal wavelength shift;
a receiver configured to receive light that passes through an optical path to the receiver; and
a bandpass filter that:
is configured to effectuate a thermal wavelength shift that does not deviate from the linear thermal wavelength shift of the semiconductor laser by more than 40%; and
includes a shift element and a plurality of filter segments whose transmission properties differ from one another;

wherein:
the shift element is configured to change which of the plurality of filter segments is positioned in the optical path in dependence on changes in temperature; and
the control unit is configured to control obstacle avoidance of the motor vehicle based on the determined obstacle distance.

9. The LIDAR system of claim 1 , wherein the bandpass filter is made at least partially of amorphous silicon.

Assignees

• Bosch Gmbh Robert

Inventors

• Heussner Nico
• Spiessberger Stefan

Classifications

• G02F1/0147

  based on thermo-optic effects (G02F1/132 takes precedence) · CPC title

• G01S7/4814 Primary

  of transmitters alone · CPC title

• G01S7/4911 Primary

  Transmitters · CPC title

• G02F1/218

  using semi-conducting materials · CPC title

• G01S17/08

  for measuring distance only (indirect measurement G01S17/46; active triangulation systems G01S17/48) · CPC title