# US 12,007,480 B2 · Techniques for detecting cross-talk interferences in LiDAR imaging sensors with multiple light sources > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,007,480 B2 - Document ID: US12007480B2 - Status: Granted - Kind: B2 - Application number: 17/471,781 - Filed: 2021-09-10 - Published: 2021-12-30 - Granted: 2024-06-11 - Earliest claimed: 2019-10-02 - Assignees: Cepton Technologies, Inc. - Applicants: Cepton Technologies, Inc. - Inventors: Jon Day Allen; Dongyi Liao; Mark A. McCord - Web page: https://patentgrep.com/patent/US12007480B2 ## CPC - G01S 17/10: using transmission of interrupted, pulse-modulated waves (determination of distance by phase measurements G01S17/32) - G01S 7/4815: {using multiple transmitters} - G01S 7/487: Extracting wanted echo signals {, e.g. pulse detection} - G01S 17/894: Three-dimensional [3D] imaging with simultaneous measurement of time-of-flight at a two-dimensional [2D] array of receiver pixels, e.g. time-of-flight cameras or flash lidar - G01S: RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES ## Abstract A LiDAR system includes one or more light sources configured to emit a set of light pulses in a temporal sequence with randomized temporal spacings between adjacent light pulses, one or more detectors configured to receive a set of return light pulses, and a processor configured to: determine a time of flight for each return light pulse of the set of return light pulses; and obtain a point cloud based on the times of flight of the set of return light pulses. Each point corresponds to a respective return light pulse. The processor is further configured to, for each respective point of the set of points in the point cloud: analyze spatial and temporal relationships between the respective point and a set of neighboring points in the set of points; and evaluate a quality factor for the respective point based on the spatial and temporal relationships. ## Claims ### Claim 1 A LiDAR system comprising: a plurality of light sources disposed as an array and configured to emit a plurality of sets of light pulses to be directed toward a scene within a field of view of the LiDAR system, wherein: each respective set of light pulses comprises a plurality of light pulses in a temporal sequence, each respective light pulse is emitted by a respective light source of the plurality of light sources, and the plurality of light pulses being emitted by the plurality of light sources in a randomized order; a plurality of detectors disposed as an array, each respective detector corresponding to a respective light source, the plurality of detectors configured to detect a plurality of return light pulses, at least a subset of the plurality of return light pulses corresponds to the plurality of sets of light pulses that have been reflected off of one or more objects in the scene; and a processor coupled to the plurality of light sources and the plurality of detectors, the processor configured to: determine a time of flight for each respective return light pulse of the plurality of return light pulses; obtain a point cloud based on the times of flight of the plurality of return light pulses, the point cloud including a plurality of points representing one or more surfaces of the one or more objects, each respective point corresponding to a respective return light pulse; and for each respective point in the point cloud: analyze spatial and temporal relationships between the respective point and neighboring points in the point cloud; and evaluate a quality factor for the respective point based on the spatial and temporal relationships. ### Claim 2 (depends on 1) The LiDAR system of claim 1, wherein the plurality of sets of light pulses are temporally separated from each other by randomized time delays. ### Claim 3 (depends on 1) The LiDAR system of claim 1 wherein the plurality of light pulses in each respective set of light pulses is separated from each other by an equal temporal spacing between adjacent light pulses. ### Claim 4 (depends on 1) The LiDAR system of claim 1 wherein the plurality of light pulses in each respective set of light pulses is separated from each other by randomized temporal spacings between adjacent light pulses. ### Claim 5 (depends on 1) The LiDAR system of claim 1 wherein analyzing the spatial and temporal relationships between the respective point and the neighboring points comprises: for each respective neighboring point, evaluating a partial quality factor that is inversely proportional to a spatial and temporal separation between the respective point and the respective neighboring point; and evaluating a sum of partial quality factor values of the set of neighboring points. ### Claim 6 (depends on 5) The LiDAR system of claim 5 wherein the spatial and temporal separation between the respective point and the respective neighboring point relates to an angular separation, a range separation, and a temporal separation. ### Claim 7 A method of operating a LiDAR system, the method comprising: emitting, using a plurality of light sources disposed as an array, a plurality of sets of light pulses to be directed toward a scene within a field of view of the LiDAR system, wherein: each respective set of light pulses comprises a plurality of light pulses in a temporal sequence, each respective light pulse being emitted by a respective light source of the plurality of light sources, and the plurality of light pulses being emitted by the plurality of light sources in a randomized order; detecting, using a plurality of detectors disposed as an array, a plurality of return light pulses, wherein each respective detector corresponds to a respective light source, and at least a subset of the plurality of return light pulses corresponds to the plurality of sets of light pulses that have been reflected off of one or more objects in the scene; determining a time of flight for each respective return light pulse of the plurality of return light pulses; obtaining a point cloud based on the times of flight of the plurality of return light pulses, the point cloud including a plurality of points representing one or more surfaces of the one or more objects, each respective point corresponding to a respective return light pulse; and for each respective point in the point cloud: analyzing spatial and temporal relationships between the respective point and neighboring points in the point cloud; and evaluating a quality factor for the respective point based on the spatial and temporal relationships. ### Claim 8 (depends on 7) The method of claim 7 wherein the plurality of sets of light pulses are temporally separated from each other by randomized time delays. ### Claim 9 (depends on 7) The method of claim 7 wherein the plurality of light pulses in each respective set of light pulses is separated from each other by an equal temporal spacing between adjacent light pulses. ### Claim 10 (depends on 7) The method of claim 7 wherein the plurality of light pulses in each respective set of light pulses is separated from each other by randomized temporal spacings between adjacent light pulses. ### Claim 11 (depends on 7) The method of claim 7 wherein analyzing the spatial and temporal relationships between the respective point and the neighboring points comprises: for each respective neighboring point, evaluating a partial quality factor that is inversely proportional to a spatial and temporal separation between the respective point and the respective neighboring point; and evaluating a sum of partial quality factor values of the set of neighboring points. ### Claim 12 (depends on 11) The method of claim 11 wherein the spatial and temporal separation between the respective point and the respective neighboring point relates to an angular separation, a range separation, and a temporal separation.