# US 11,310,410 B2 · Image capturing apparatus, method of controlling same, and storage medium > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,310,410 B2 - Document ID: US11310410B2 - Status: Granted - Kind: B2 - Application number: 16/707,784 - Filed: 2019-12-09 - Published: 2020-06-18 - Granted: 2022-04-19 - Earliest claimed: 2018-12-12 - Assignees: Canon Kabushiki Kaisha - Applicants: Canon Kabushiki Kaisha - Inventors: Kazuma Sakato; Yohei Horikawa - Web page: https://patentgrep.com/patent/US11310410B2 ## CPC - H04N 23/672: {based on the phase difference signals} - G03B 13/32: Means for focusing - G06T 7/80: Analysis of captured images to determine intrinsic or extrinsic camera parameters, i.e. camera calibration - H04N 23/73: by influencing the exposure time - G06T 2207/20212: Image combination - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION - G03B: APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR (optical parts of such apparatus G02B; photosensitive materials or processes for photographic purposes G03C; apparatus for processing exposed photographic materials G03D) - G06T: IMAGE DATA PROCESSING OR GENERATION, IN GENERAL ## Abstract An image capturing apparatus is provided with an image sensor having phase difference detection pixels for performing focus detection, an exposure control unit for causing at least the phase difference detection pixels to perform a plurality of accumulations whose exposure periods are a second exposure period shorter than a first exposure period which is a target for obtaining a main image by the image sensor, and a prediction unit for predicting an in-focus position of a subject based on signals of at least two phase difference detection pixels obtained by at least two accumulations among the plurality of accumulations whose exposure periods are the second exposure period. ## Claims ### Claim 1 An image capturing apparatus, comprising: an image sensor having phase difference detection pixels for performing focus detection; and at least one processor or circuit configured to function as the following units: an exposure control unit configured to cause at least the phase difference detection pixels to perform a plurality of accumulations whose exposure periods are a second exposure period shorter than a first exposure period which is a target for obtaining a main image by the image sensor; and a prediction unit configured to predict an in-focus position of a subject based on signals of at least two of the phase difference detection pixels obtained in at least two accumulations out of the plurality of accumulations whose exposure periods are a second exposure period. ### Claim 2 (depends on 1) The image capturing apparatus according to claim 1, wherein the exposure control unit causes the image sensor to perform exposure over a plurality of the second exposure period so that a sum of the plurality of the second exposure period becomes the first exposure period, and the at least one processor or circuit is configured to further function as a combining unit configured to generate the main image by combining a plurality of image signals obtained by the plurality of accumulations whose exposure periods are the second exposure period. ### Claim 3 (depends on 1) The image capturing apparatus according to claim 1, wherein the prediction unit predicts the in-focus position of the subject using thinned-out signals that are at equal intervals among signals obtained by the plurality of accumulations whose exposure periods are the second exposure period. ### Claim 4 (depends on 3) The image capturing apparatus according to claim 3, wherein the exposure control unit adjusts an interval for performing accumulation over the first exposure period based on an interval for performing a calculation for predicting an in-focus position of the subject. ### Claim 5 (depends on 3) The image capturing apparatus according to claim 3, wherein the image sensor outputs a signal used for generating the main image at a timing of outputting a signal that is thinned-out and is not used for predicting the in-focus position of the subject. ### Claim 6 (depends on 1) The image capturing apparatus according to claim 1, wherein the prediction unit predicts the in-focus position of the subject using thinned-out signals that are not at equal intervals among signals obtained by the plurality of accumulations whose exposure periods are the second exposure period. ### Claim 7 (depends on 6) The image capturing apparatus according to claim 6, wherein the prediction unit predicts the in-focus position of the subject using the signal obtained in a last accumulation in the first exposure period among the signals obtained in the plurality of accumulations whose exposure periods are the second exposure period. ### Claim 8 (depends on 6) The image capturing apparatus according to claim 6, wherein the prediction unit predicts the in-focus position of the subject so that the prediction of the in-focus position of the subject ends before the first exposure period ends. ### Claim 9 (depends on 8) The image capturing apparatus according to claim 8, wherein the at least one processor or circuit is configured to further function as a lens control unit configured to perform control for focusing a photographing lens, and the lens control unit drives the photographing lens in the first exposure period. ### Claim 10 (depends on 1) The image capturing apparatus according to claim 1, wherein the prediction unit comprises a selection circuit for selecting a method of predicting the in-focus position of the subject. ### Claim 11 (depends on 1) The image capturing apparatus according to claim 1, wherein the exposure control unit drives the image sensor by a slit rolling shutter method. ### Claim 12 (depends on 1) The image capturing apparatus according to claim 1, wherein the image sensor can independently perform readout of a signal for predicting the in-focus position of the subject and readout of an image signal used for generating the main image. ### Claim 13 An image capturing apparatus, comprising: an image sensor having phase difference detection pixels for performing focus detection; and at least one processor or circuit configured to function as the following units: an exposure control unit configured to cause at least the phase difference detection pixels to perform a plurality of accumulations whose exposure periods are a second exposure period shorter than a first exposure period which is a target for obtaining a main image by the image sensor; a comparison unit configured to compare a length of the first exposure period with a threshold; and a prediction unit configured to, based on a result of comparison by the comparison unit, select one of a signal obtained by accumulation over the first exposure period and a signal obtained by accumulation over the second exposure period, and predict an in-focus position of a subject. ### Claim 14 (depends on 13) The image capturing apparatus according to claim 13, wherein the prediction unit predicts the in-focus position of the subject using the signal obtained by accumulation over the first exposure period when the length of the first exposure period is shorter than the threshold, and predicts the in-focus position of the subject using the signal obtained by accumulation over the second exposure period when the length of the first exposure period is greater than or equal to the threshold. ### Claim 15 A method of controlling an image capturing apparatus provided with an image sensor having phase difference detection pixels for performing focus detection, the method comprising: causing at least the phase difference detection pixels to perform a plurality of accumulations whose exposure periods are a second exposure period shorter than a first exposure period which is a target for obtaining a main image by the image sensor; and predicting an in-focus position of a subject based on signals of at least two of the phase difference detection pixels obtained in at least two accumulations out of the plurality of accumulations whose exposure periods are the second exposure period. ### Claim 16 A method of controlling an image capturing apparatus provided with an image sensor having phase difference detection pixels for performing focus detection, the method comprising: causing at least the phase difference detection pixels to perform a plurality of accumulations whose exposure periods are a second exposure period shorter than a first exposure period which is a target for obtaining a main image by the image sensor; comparing a length of the first exposure period with a threshold; and based on a result of the comparison, selecting one of a signal obtained by accumulation over the first exposure period and a signal obtained by accumulation over the second exposure period, and predicting an in-focus position of a subject. ### Claim 17 A non-transitory computer readable storage medium storing a program for causing a computer to execute steps of a method of controlling an image capturing apparatus comprising an image sensor having phase difference detection pixels for performing focus detection, the method comprising: causing at least the phase difference detection pixels to perform a plurality of accumulations whose exposure periods are a second exposure period shorter than a first exposure period which is a target for obtaining a main image by the image sensor; and predicting an in-focus position of a subject based on signals of at least two of the phase difference detection pixels obtained in at least two accumulations out of the plurality of accumulations each over the second exposure period. ### Claim 18 A non-transitory computer readable storage medium storing a program for causing a computer to execute steps of a method of controlling an image capturing apparatus comprising an image sensor having phase difference detection pixels for performing focus detection, the method comprising: causing at least the phase difference detection pixels to perform a plurality of accumulations whose exposure periods are a second exposure period shorter than a first exposure period which is a target for obtaining a main image by the image sensor; comparing a length of the first exposure period with a threshold; and based on a result of the comparison, selecting one of a signal obtained by accumulation over the first exposure period and a signal obtained by accumulation over the second exposure period, and predicting an in-focus position of a subject.