Solid state light detection and ranging (lidar) system and system and method for improving solid state light detection and ranging (lidar) resolution

Abstract

A sensor system can comprise a detector with a plurality of units, wherein the detector is configured to generate a first set of electrical signals based on received photon energy of a light beam that is reflected back from a first plurality of points on one or more objects, in a first configuration. Additionally, the detector is configured to generate a second set of electrical signals based on received photon energy of a light beam that is reflected back from a second plurality of points on one or more objects in a second configuration, wherein the first configuration and the second configuration are with a predetermined correlation. Furthermore, the detector can determine distance to each of the first plurality of points and the second plurality of points on the one or more objects based on the first set of electrical signals and the second set of electrical signals.

What is claimed is: 
     
         1 . A sensor system, comprising:
 a light source configured to emit a laser beam; and   a detector comprising a plurality of photon detection devices, wherein the detector is configured to:
 generate a first set of electrical signals based on a first portion of the laser beam received by the plurality of photon detection devices in a first configuration, wherein the first portion of the laser beam is reflected by a first plurality of points on one or more objects in a FOV of the sensor system and the first set of electrical signals corresponds to a first set of pixels; 
 generate a second set of electrical signals based on a second portion of the laser beam received by the plurality of photon detection devices in a second configuration, wherein the second portion of the laser beam is reflected by a second plurality of points on the one or more objects in the FOV of the sensor system and the second set of electrical signals corresponds to a second set of pixels; and 
 switch the plurality of photon detection devices between the first configuration and the second configuration to cause a pixel shift between the first set of pixels and the second set of pixels. 
   
     
     
         2 . The sensor system of  claim 1 , further comprising:
 an expander configured to expand the laser beam;   a homogenizer configured to homogenize the expanded laser beam so as to scan surrounding environment in the FOV of the sensor system; and   a collimator configured to collimate the laser beam.   
     
     
         3 . The sensor system of  claim 2 , wherein the light source, the collimator, the expander, the homogenizer are disposed in this order in a direction of the emitted laser beam. 
     
     
         4 . The sensor system of  claim 1 , further comprising one or more optical structures to capture and direct the reflected laser beam toward the detector. 
     
     
         5 . The sensor system of  claim 1 , wherein the light source is a solid-state laser. 
     
     
         6 . The sensor system of  claim 2 , wherein the expander comprises a pair of a concave lens and a convex lens. 
     
     
         7 . The sensor system of  claim 2 , wherein the homogenizer is a holographic filter. 
     
     
         8 . The sensor system of  claim 7 , further comprising a first lens and a second lens after the homogenizer, wherein the first lens directs each group of parallel rays transmitted from the holographic filter to a particular point on a focal plane of the first lens, and the second lens has the same focal length as the first lens, is disposed on the focal plane of the first lens, and corrects divergence of telecentric cone angles exiting from the focal plane and creates a telecentric light field. 
     
     
         9 . The sensor system of  claim 1 , wherein each of the plurality of photon detection devices comprises a detecting structure and a micro-lens on top of the detection structure. 
     
     
         10 . The sensor system of  claim 9 , wherein the detection structure is an APD cell. 
     
     
         11 . The sensor system of  claim 10 , wherein the detection structure further comprises a readout integrated circuit to read out photon detection events based on the generated electrical signals by the corresponding APD cell. 
     
     
         12 . The sensor system of  claim 9 , wherein each of the plurality of photon detection devices further comprises an antireflective film between the micro-lens and the detecting structure. 
     
     
         13 . The sensor system of  claim 1 , wherein each of the plurality of photon detection devices generates one or more electrical signals that indicate distance information for one or more objects in corresponding sections of the FOV. 
     
     
         14 . The sensor system of  claim 13 , wherein each of the plurality of photon detection devices generates the electric signals independently. 
     
     
         15 . The sensor system of  claim 1 , wherein the plurality of photon detection devices are arranged in an array. 
     
     
         16 . The sensor system of  claim 1 , further comprising a timer used to trigger emission of the laser beam and provide time information related to each of the generated electrical signals. 
     
     
         17 . The sensor system of  claim 1 , wherein the sensor system further comprises a planar plate lens in front of the detector. 
     
     
         18 . The sensor system of  claim 17 , wherein the planar plate lens is configured to be at a first angle relative to incoming light in a first configuration and is configured to be at a second angle relative to incoming light in a second configuration. 
     
     
         19 . The sensor system of  claim 1 , further comprising circuitry configured to calculate distance information for each of the one or more objects based on time difference between a time point when the electric signals are generated at different photon detection devices and a time point when the laser beam is emitted. 
     
     
         20 . A method for sensing one or more objects using a detector with a plurality of photon detection devices, comprising:
 generating a first set of electrical signals based on a first portion of a laser beam received by the plurality of photon detection devices in a first configuration, wherein the first portion of the laser beam is reflected by a first plurality of points on the one or more objects in a FOV of a sensor system and the first set of electrical signals corresponds to a first set of pixels;   generating a second set of electrical signals based on a second portion of the laser beam received by the plurality of photon detection devices in a second configuration, wherein the second portion of the laser beam is reflected by a second plurality of points on the one or more objects in the FOV of the sensor system and the second set of electrical signals corresponds to a second set of pixels; and   switching the plurality of photon detection devices between the first configuration and the second configuration to cause a pixel shift between the first set of pixels and the second set of pixels.