# US 2025/0097604 A1 · Photoelectric conversion device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2025/0097604 A1 - Document ID: US20250097604A1 - Status: Published application - Kind: A1 - Application number: 18/825,667 - Filed: 2024-09-05 - Published: 2025-03-20 - Earliest claimed: 2023-09-14 - Assignees: Canon Kabushiki Kaisha - Applicants: Canon Kabushiki Kaisha - Inventors: SATOSHI OMODANI - Web page: https://patentgrep.com/patent/US20250097604A1 ## CPC - H04N 25/773: comprising photon counting circuits, e.g. single photon detection [SPD] or single photon avalanche diodes [SPAD] - G01S 7/4863: Detector arrays, e.g. charge-transfer gates - G01S 7/4865: Time delay measurement, e.g. time-of-flight measurement, time of arrival measurement or determining the exact position of a peak (peak detection in noise, signal conditioning G01S7/487) - G01S 7/487: Extracting wanted echo signals {, e.g. pulse detection} - G01S 17/14: wherein a voltage or current pulse is initiated and terminated in accordance with the pulse transmission and echo reception respectively, e.g. using counters - G01S 17/89: for mapping or imaging - G01S 17/931: of land vehicles - H04N 23/56: provided with illuminating means - H04N 25/705: Pixels for depth measurement, e.g. RGBZ - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION - 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 photoelectric conversion device includes: a light receiving unit configured to generate a light reception signal according to incident light by photoelectric conversion; a time-to-digital conversion unit configured to perform a time-to-digital conversion in which an operation of outputting a time count value indicating an elapsed time from light emission of a light source device to input of the light reception signal is periodically performed every time a predetermined period elapses in one ranging period; a weight determination unit configured to acquire a count value indicating the number of times of the time-to-digital conversion performed in the one ranging period and output a weight value based on the count value; and a frequency distribution generation unit configured to use the weight value to add a frequency in generation of a frequency distribution of the count value. ## Claims ### Claim 1 A photoelectric conversion device comprising: a light receiving unit configured to generate a light reception signal according to incident light by photoelectric conversion; a time-to-digital conversion unit configured to perform a time-to-digital conversion in which an operation of outputting a time count value indicating an elapsed time from light emission of a light source device to input of the light reception signal is periodically performed every time a predetermined period elapses in one ranging period; a weight determination unit configured to acquire a count value indicating the number of times of the time-to-digital conversion performed in the one ranging period and output a weight value based on the count value; and a frequency distribution generation unit configured to use the weight value to add a frequency in generation of a frequency distribution of the count value. ### Claim 2 (depends on 1) The photoelectric conversion device according to claim 1, wherein the weight determination unit outputs a first weight value when the count value is equal to or less than a first threshold value, and outputs a second weight value greater than the first weight value when the count value is greater than the first threshold value. ### Claim 3 (depends on 2) The photoelectric conversion device according to claim 2, wherein the weight determination unit outputs the second weight value when the count value is greater than the first threshold value and equal to or less than a second threshold value, and outputs a third weight value greater than the second weight value when the count value is greater than the second threshold value. ### Claim 4 (depends on 1) The photoelectric conversion device according to claim 1, wherein the weight determination unit outputs the weight value by referring to a table indicating a correspondence relationship between the count value and the weight value. ### Claim 5 (depends on 1) The photoelectric conversion device according to claim 1, wherein the weight determination unit outputs the weight value using a function indicating a correspondence relationship between the count value and the weight value. ### Claim 6 (depends on 1) The photoelectric conversion device according to claim 1, wherein the weight determination unit further acquires a total number of operations that is a setting value of a total number of times the time-to-digital conversion unit repeats an operation of outputting the time count value in the one ranging period, and wherein the weight determination unit outputs the weight value further based on the total number of operations. ### Claim 7 (depends on 6) The photoelectric conversion device according to claim 6, wherein a correspondence relationship between the count value and the weight value is set to be different according to the total number of operations. ### Claim 8 (depends on 6) The photoelectric conversion device according to claim 6, wherein the weight determination unit outputs a first weight value when the count value is equal to or less than a threshold value, and outputs a second weight value greater than the first weight value when the count value is greater than the threshold value, and wherein the threshold value is set to be different according to the total number of operations. ### Claim 9 (depends on 8) The photoelectric conversion device according to claim 8, wherein the threshold value is set to be greater as the total number of operations is greater. ### Claim 10 (depends on 8) The photoelectric conversion device according to claim 8, wherein the threshold value is set to be proportional to the total number of operations. ### Claim 11 (depends on 1) The photoelectric conversion device according to claim 1, wherein the weight value is 2M (M is an integer), and wherein a value of the M is different depending on the count value. ### Claim 12 (depends on 1) The photoelectric conversion device according to claim 1, wherein the frequency distribution generation unit generates distance information based on the frequency distribution. ### Claim 13 (depends on 12) The photoelectric conversion device according to claim 12, wherein the frequency distribution generation unit detects a maximum value of the count value and generates the distance information based on a time count value corresponding to the maximum value. ### Claim 14 (depends on 1) The photoelectric conversion device according to claim 1, wherein the frequency distribution generation unit generates velocity information of an object based on the frequency distribution. ### Claim 15 (depends on 14) The photoelectric conversion device according to claim 14, wherein the frequency distribution generation unit acquires a speed of the object based on a magnitude of variation in the count value indicated by the frequency distribution. ### Claim 16 (depends on 14) The photoelectric conversion device according to claim 14, wherein the frequency distribution generation unit acquires a direction of a velocity of the object based on an asymmetry of variation in the count value indicated by the frequency distribution. ### Claim 17 (depends on 1) The photoelectric conversion device according to claim 1, wherein the light receiving unit includes an avalanche photodiode. ### Claim 18 (depends on 1) A photodetection system comprising: the photoelectric conversion device according to claim 1; and a signal processing unit configured to process a signal output from the photoelectric conversion device. ### Claim 19 (depends on 1) A photodetection system comprising: the photoelectric conversion device according to claim 1; a signal processing unit configured to process a signal output from the photoelectric conversion device; and the light source device. ### Claim 20 (depends on 1) A movable body comprising: the photoelectric conversion device according to claim 1; and a movable body control unit configured to control the movable body based on distance information acquired by the photoelectric conversion device.