Selective illumination in LIDAR based on detection results
A LIDAR system is provided. The LIDAR system comprises at least one processor configured to: control at least one light source in a manner enabling light flux to vary over a scan of a field of view using light from the at least one light source; control at least one light deflector to deflect light from the at least one light source; use first detected reflections associated with a scan of a first portion of the field of view to determine an existence of a first object in the first portion at a first distance; determine an absence of objects in a second portion of the field of view at the first distance; alter a light source parameter; and use second detected reflections in the second portion of the field of view to determine an existence of a second object at a second distance greater than the first distance.
1. A LIDAR system, comprising:
at least one processor configured to:
control at least one light source in a manner enabling light flux to vary over a scan of a field of view using light from the at least one light source;
control at least one light deflector to deflect light from the at least one light source in order to scan the field of view;
use first detected reflections associated with a scan of a first portion of the field of view to determine an existence of a first object in the first portion at a first distance;
determine an absence of objects in a second portion of the field of view at the first distance;
following the detection of the first reflections and the determination of the absence of objects in the second portion, alter a light source parameter such that more light is projected toward the second portion of the field of view than is projected toward the first portion of the field of view; and
use second detected reflections in the second portion of the field of view to determine an existence of a second object at a second distance greater than the first distance.
2. The LIDAR system of claim 1 , wherein the at least one processor is further configured to control the at least one light deflector such that the at least one light deflector is pivoted in two orthogonal axis.
3. The LIDAR system of claim 1 , wherein the at least one processor is further configured to control a rotatable motor for steering the at least one light deflector.
4. The LIDAR system of claim 1 , wherein the at least one light deflector includes a pivotable MEMS mirror.
5. The LIDAR system of claim 1 , wherein a single scanning cycle of the field of view includes moving the at least one light deflector such that during the scanning cycle the at least one light deflector is located at a plurality of different instantaneous positions, and wherein the at least one processor is configured to control the at least one light source and the at least one light detector such that while the at least one light deflector is located at a particular instantaneous position, a light beam from the at least one light source is deflected by the at least one deflector toward an object in the field of view, and reflections from the object are deflected by the at least one light deflector toward at least one sensor.
6. The LIDAR system of claim 5 , wherein the second portion of the field of view corresponds to a single instantaneous position of the at least one light deflector.
7. The LIDAR system of claim 5 , wherein the second portion of the field of view corresponds to a plurality of instantaneous positions of the at least one light deflector.
8. The LIDAR system of claim 5 , wherein the at least one processor is further configured to alter the light source parameter such that more irradiance per solid angle is projected toward the second portion of the field of view in a same scanning cycle in which the absence of objects in the second portion at the first distance is determined.
9. The LIDAR system of 8 , wherein the at least one light deflector includes a pivotable MEMS mirror.
10. The LIDAR system of claim 1 , wherein the at least one processor is further configured to alter the light source parameter such that the more light is projected toward the second portion of the field of view in a same scanning cycle in which the absence of objects in the second portion at the first distance is determined.
11. The LIDAR system of claim 8 , wherein the at least one processor is further configured to use a third detected reflection associated with a scan of the second portion to determine the absence of objects in the second portion at the first distance, and to use the third detected reflection and the second detected reflections to determine the existence of the second object at the second distance.
12. The LIDAR system of claim 1 , wherein the at least one processor is further configured to control the at least one light source and the at least one light deflector such that the second reflections are detected in subsequent scanning cycle following a prior scanning cycle in which the absence of the object in the second portion at the first distance was determined.
13. The LIDAR system of claim 12 , wherein the at least one processor is further configured to control the at least one light source such that an amount of light projected toward the first portion in the subsequent scan is substantially the same as an amount of light projected toward the first portion in the prior scan.
14. The LIDAR system of claim 1 , wherein the at least one processor is further configured to alter the light source parameter such that the more light is projected toward the second portion in response to determining the absence of objects in the second portion at the first distance.
15. The LIDAR system of claim 1 , wherein the at least one processor is further configured to alter the light source parameter such that flux of light directed to the second portion of the field of view is greater than flux of light directed to the first portion of the field of view.
16. The LIDAR system of claim 1 , wherein the light source parameter includes light pulse power and the at least one processor is further configured to alter the light source parameter to increase power of light pulses projected toward the second portion of the field of view.
17. The LIDAR system of claim 1 , wherein the light source parameter includes a light-pulse-repetition number per scan and the at least one processor is further configured to alter the light source parameter to project more light pulses to the second portion than a number of light pulses projected toward to the first portion.
18. A method for detecting objects using a LIDAR system, the method comprising:
controlling at least one light source in a manner enabling light flux to vary over a scan of a field of view using light from the at least one light source;
controlling at least one light deflector to deflect light from the at least one light source in order to scan the field of view;
using first detected reflections associated with a scan of a first portion of the field of view to determine an existence of a first object in the first portion at a first distance;
determining an absence of objects in a second portion of the field of view at the first distance;
following the detection of the first reflections and the determination of the absence of objects in the second portion, altering a light source parameter such that more light is projected toward the second portion of the field of view than is projected toward the first portion of the field of view; and
using second detected reflections in the second portion of the field of view determine an existence of a second object at a second distance greater than the first distance.
19. The method of claim 18 , wherein scanning includes undertaking a plurality of scanning cycles, wherein a single scanning cycle includes moving the at least one light deflector across a plurality of instantaneous positions, and wherein while the at least one light deflector is located at a particular instantaneous position, the method includes deflecting a light beam from the at least one light source toward an object in the field of view, and deflecting received reflections from the object toward at least one sensor.
20. The method of claim 18 , wherein the second portion of the field of view corresponds to a single instantaneous position of the at least one light deflector.
21. The method of claim 18 , wherein the second portion of the field of view corresponds to a plurality of instantaneous positions of the at least one light deflector.
22. The method of claim 18 , further comprising detecting the second reflections in a same scanning cycle in which the absence of the object in the second portion at the first distance was determined.
23. The method of claim 18 , further comprising detecting the second reflections in subsequent scanning cycle following a prior scanning cycle in which the absence of the object in the second portion at the first distance was determined.
24. The method of claim 18 , further comprising using third detected reflections associated with a scan of the second portion to determine the absence of objects in the second portion at the first distance, and to use the third detected reflection and the second detected reflections to determine the existence of the second object at the second distance.
25. A non-transitory computer-readable storage medium storing instructions that, when executed by at least one processor, cause the at least one processor to perform a method for detecting objects using a LIDAR system, the method comprising:
controlling at least one light source in a manner enabling light flux to vary over a scan of a field of view using light from the at least one light source;
controlling at least one light deflector to deflect light from the at least one light source in order to scan the field of view;
using first detected reflections associated with a scan of a first portion of the field of view to determine an existence of a first object in the first portion at a first distance;
determining an absence of objects in a second portion of the field of view at the first distance;
following the detection of the first reflections and the determination of the absence of objects in the second portion, altering a light source parameter such that more light is projected toward the second portion of the field of view than is projected toward the first portion of the field of view; and
using second detected reflections in the second portion of the field of view determine an existence of a second object at a second distance greater than the first distance.