Fast scanning lidar with dynamic voxel probing

Abstract

A LIDAR system includes a scanner; a receiver; and one or more processor devices to perform actions, including: scanning a continuous light beam over the field of view in a first scan pass; detecting photons of the continuous light beam that are reflected from one or more objects; determining a coarse range to the one or more objects based on times of departure of the photons of the continuous light beam and times of arrival of the photons at the receiver; scanning light pulses over the field of view in a second scan pass; detecting photons from the light pulses that are reflected from the one or more objects; and determining a refined range to the one or more objects based on times of departure of the photons of the light pulses and times of arrival of the photons at the receiver.

1 . A method for measuring a range of one or more objects, the method comprising:
 employing one or more scanners to scan one or more light beams at the one or more objects;   employing the one or more light beams that are reflected by the one or more objects to determine the range between the one or more scanners and the one or more objects;   employing a time period of activation for each pixel of a receiver arranged to detect reflection of the one or more of light beams by determining an estimated arrival time of photons corresponding to a direct path of the reflection of the one or more light beams by the one or more objects; and   redetermining the range based on subsequent detected reflection of the one or more light beams during each time period of activation for each pixel of the receiver.   
     
     
         2 . The method of  claim 1 , wherein employing the one or more scanners to scan the one or more light beams further comprises:
 scanning one or more continuous light beams and one or more pulsed light beams at the one or more objects;   employing reflection of the one or more continuous light beams reflected by the one or more objects to determine a coarse range between the one or more scanners and the one or more objects; and   employing reflection of the one or more pulsed light beams reflected by the one or more objects to determine a refined range between the one or more scanners and the one or more objects.   
     
     
         3 . The method of  claim 1 , wherein reflection of the one or more light beams further comprises:
 sequentially scanning of each activated pixel of the receiver for the direct path of the reflection of the one or more light beams by the one or more objects.   
     
     
         4 . The method of  claim 1 , further comprising:
 in response to determining the range between the one or more scanners and the one or more objects, scanning another light beam having a visible wavelength that is reflected by the one or more objects, wherein reflection of the other light beam is employed to refine the determined range between the one or more scanners and the one or more objects.   
     
     
         5 . The method of  claim 1 , further comprising:
 in response to determining the range between the one or more scanners and the one or more objects, reducing a field of view for the scan of the one or more light beams at the one or more objects by the one or more scanners; and   employing the reduced field of view to provide for faster scanning of the one or more light beams at the one or more objects and faster detection of reflection of the one or more light beams by the receiver.   
     
     
         6 . The method of  claim 1 , wherein employing the one or more scanners to scan the one or more light beams at the one or more objects further comprises:
 employing two scanners to laterally scan the one or more light beams at the one or more objects at different velocities in opposing directions.   
     
     
         7 . The method of  claim 1 , wherein the one or more scanners further comprise one or more single photon avalanche diode (SPAD) for each pixel employed to detect reflection of the one or more light beams by the one or more objects. 
     
     
         8 . A device for measuring a range of one or more objects, comprising:
 a memory for instructions; and   one or more processors that execute the instructions to perform actions, including:
 employing one or more scanners to scan one or more light beams at the one or more objects; 
 employing the one or more light beams that are reflected by the one or more objects to determine the range between the one or more scanners and the one or more objects; 
 employing a time period of activation for each pixel of a receiver arranged to detect reflection of the one or more of light beams by determining an estimated arrival time of photons corresponding to a direct path of the reflection of the one or more light beams by the one or more objects; and 
   redetermining the range based on subsequent detected reflection of the one or more light beams during each time period of activation for each pixel of the receiver.   
     
     
         9 . The device of  claim 8 , wherein employing the one or more scanners to scan the one or more light beams further comprises:
 scanning one or more continuous light beams and one or more pulsed light beams at the one or more objects;   employing reflection of the one or more continuous light beams reflected by the one or more objects to determine a coarse range between the one or more scanners and the one or more objects; and   employing reflection of the one or more pulsed light beams reflected by the one or more objects to determine a refined range between the one or more scanners and the one or more objects.   
     
     
         10 . The device of  claim 8 , wherein reflection of the one or more light beams further comprises:
 sequentially scanning of each activated pixel of the receiver for the direct path of the reflection of the one or more light beams by the one or more objects.   
     
     
         11 . The device of  claim 8 , further comprising:
 in response to determining the range between the one or more scanners and the one or more objects, scanning another light beam having a visible wavelength that is reflected by the one or more objects, wherein reflection of the other light beam is employed to refine the determined range between the one or more scanners and the one or more objects.   
     
     
         12 . The device of  claim 8 , further comprising:
 in response to determining the range between the one or more scanners and the one or more objects, reducing a field of view for the scan of the one or more light beams at the one or more objects by the one or more scanners; and   employing the reduced field of view to provide for faster scanning of the one or more light beams at the one or more objects and faster detection of reflection of the one or more light beams by the receiver.   
     
     
         13 . The device of  claim 8 , wherein employing the one or more scanners to scan the one or more light beams at the one or more objects further comprises:
 employing two scanners to laterally scan the one or more light beams at the one or more objects at different velocities in opposing directions.   
     
     
         14 . The device of  claim 8 , wherein the one or more scanners further comprise one or more single photon avalanche diode (SPAD) for each pixel employed to detect reflection of the one or more light beams by the one or more objects. 
     
     
         15 . A computer readable non-transitory media that includes instructions for measuring a range of one or more objects, wherein execution of the instructions by one or more processors performs actions, comprising:
 employing one or more scanners to scan one or more light beams at the one or more objects;   employing the one or more light beams that are reflected by the one or more objects to determine the range between the one or more scanners and the one or more objects;   employing a time period of activation for each pixel of a receiver arranged to detect reflection of the one or more of light beams by determining an estimated arrival time of photons corresponding to a direct path of the reflection of the one or more light beams by the one or more objects; and   redetermining the range based on subsequent detected reflection of the one or more light beams during each time period of activation for each pixel of the receiver.   
     
     
         16 . The media of  claim 15 , wherein reflection of the one or more light beams further comprises:
 sequentially scanning of each activated pixel of the receiver for the direct path of the reflection of the one or more light beams by the one or more objects.   
     
     
         17 . The media of  claim 15 , further comprising:
 in response to determining the range between the one or more scanners and the one or more objects, scanning another light beam having a visible wavelength that is reflected by the one or more objects, wherein reflection of the other light beam is employed to refine the determined range between the one or more scanners and the one or more objects.   
     
     
         18 . The media of  claim 15 , further comprising:
 in response to determining the range between the one or more scanners and the one or more objects, reducing a field of view for the scan of the one or more light beams at the one or more objects by the one or more scanners; and   employing the reduced field of view to provide for faster scanning of the one or more light beams at the one or more objects and faster detection of reflection of the one or more light beams by the receiver.   
     
     
         19 . The media of  claim 15 , wherein employing the one or more scanners to scan the one or more light beams at the one or more objects further comprises:
 employing two scanners to laterally scan the one or more light beams at the one or more objects at different velocities in opposing directions.   
     
     
         20 . The media of  claim 15 , wherein the one or more scanners further comprise one or more single photon avalanche diode (SPAD) for each pixel employed to detect reflection of the one or more light beams by the one or more objects.