公开(公告)号：US20240288557A1

公开(公告)日：2024-08-29

申请号：US18176163

申请日：2023-02-28

Applicant: STMicroelectronics International N.V.

Inventor： Stuart McLeod ,  Andreas Assmann

IPC: G01S7/4865 ,  G01S7/48 ,  G01S17/89

CPC classification number: G01S7/4865 ,  G01S7/4808 ,  G01S17/89

Abstract: A method of determining a distance of a closest target using a time-of-flight (ToF) ranging system includes: receiving, by a processor, a histogram generated by a ToF imager of the ToF ranging system, where the ToF imager is configured to transmit a light pulse for ranging purpose; finding a first rising edge in the histogram that corresponds to a rising edge of a reflected light pulse from the closest target; and calculating a first estimate of the distance of the closest target by adding a pre-determined offset to a distance of the first rising edge.

公开(公告)号：US20240353538A1

公开(公告)日：2024-10-24

申请号：US18304589

申请日：2023-04-21

Applicant: STMicroelectronics International N.V.

Inventor： Andreas Assmann

IPC: G01S7/4865 ,  G01S17/894

CPC classification number: G01S7/4865 ,  G01S17/894

Abstract: A method of ranging using a time-of-flight (ToF) ranging system includes: receiving, by a processor, a histogram generated by a ToF imager of the ToF ranging system, where the ToF imager is configured to transmit a light pulse for ranging purpose; finding a rising edge of a pulse region in the histogram, where the pulse region corresponds to a reflected light pulse from a target; fine-tuning a location of the rising edge by performing a fitting process between the rising edge and a pre-stored high-solution rising edge; and calculating an estimate of a distance of the target by adding a pre-determined offset to a distance of the rising edge after fine-tuning the location of the rising edge.

公开(公告)号：US20240192337A1

公开(公告)日：2024-06-13

申请号：US18064412

申请日：2022-12-12

Applicant: STMicroelectronics International N.V.

Inventor： Andreas Assmann

IPC: G01S7/4865 ,  G01S7/481 ,  G01S17/894

CPC classification number: G01S7/4865 ,  G01S7/4813 ,  G01S7/4816 ,  G01S17/894

Abstract: A method of processing a histogram generated by a time-of-flight (ToF) imager includes: filtering the histogram using a zero-crossing filter (ZCF) to generate a ZCF output signal; finding zero-crossing points in the ZCF output signal, where the zero-crossing points define one or more pulse regions in the ZCF output signal; computing, for each pulse region of the one or more pulse regions, a weighted sum of the pulse region; finding, in each pulse region, a maximum peak; classifying the maximum peak in each pulse region as a first type of peak or a second type of peak based on the weighted sum of the pulse region; and generating a list of ZCF targets from the maximum peaks classified as the first type of peaks.

公开(公告)号：US20250012901A1

公开(公告)日：2025-01-09

申请号：US18348600

申请日：2023-07-07

Applicant: STMicroelectronics International N.V.

Inventor： Andreas Assmann

IPC: G01S7/4865

Abstract: A method of operating a time-of-flight (ToF) ranging system includes: receiving a histogram that includes a cross-talk signal generated by reflected light pulses from a cover glass of the ToF ranging system; finding, in a first region of the histogram, a first rising edge having a gradient that is larger than a threshold or is a maximum gradient in the first region, where the first rising edge is in a first histogram bin having a first value; determining a second value of a second histogram bin in the first region, where the first histogram bin precedes the second histogram bin by a pre-determined distance; estimating a ratio between the first region of the histogram and a pre-stored light pulse shape based on the first value and the second value; scaling the pre-stored light pulse shape with the estimated ratio; and subtracting the scaled pre-stored light pulse shape from the histogram.

公开(公告)号：US20250008232A1

公开(公告)日：2025-01-02

申请号：US18342965

申请日：2023-06-28

Applicant: STMicroelectronics International N.V.

Inventor： Stuart McLeod ,  Andreas Assmann

IPC: H04N25/46

Abstract: A method of operating a time-of-flight (ToF) ranging system includes: transmitting, by an emitter, a light signal toward one or more targets; receiving, by a ToF sensor, the light signal reflected by the one or more targets; generating a histogram based on the received light signal; estimating gradients of histogram bins of the histogram by computing differences between adjacent histogram bins; identifying one or more pulse regions in the histogram; finding, in a pulse region, a rising edge having a gradient that is larger than a pre-determined threshold or is a maximum gradient in the pulse region, where the rising edge is a leftmost rising edge in the pulse region having the gradient; fine-tuning a location of the rising edge; and computing an estimate of a distance of a target in the pulse region by adding a pre-determined offset to a distance of the rising edge.