US-12621577-B2 - Apparatus, optical apparatus, image pickup method, and non-transitory computer-readable storage medium for correcting aberration and density unevenness among a plurality of images

US12621577B2US 12621577 B2US12621577 B2US 12621577B2US-12621577-B2

Abstract

An apparatus includes a sensor, at least one processor; and a memory coupled to the at least one processor, the at least one memory having instructions that, when executed by the at least one processor, perform to acquire array information about an optical apparatus including a filter that includes a plurality of areas to disperse a light beam from an object into a plurality of spectral components, cut out a plurality of images in a tile form from an image signal output by the sensor picking out a light beam incident from the object through the filter of the optical apparatus, and correct brightness of the plurality of images based on the array information, wherein the plurality of images each corresponds to a different area among the plurality of areas of the filter.

Inventors

Masaki Ishii

Assignees

CANON KABUSHIKI KAISHA

Dates

Publication Date: 20260505
Application Date: 20221129
Priority Date: 20211203

Claims (19)

1 . An apparatus comprising: a sensor; at least one processor; and at least one memory coupled to the at least one processor, the at least one memory having instructions that, when executed by the at least one processor, cause the apparatus to: acquire array information related to an optical apparatus to which a filter that includes a plurality of areas to disperse a light beam from an object into a plurality of spectral components is able to be attached; cut out a plurality of images in a tile form from an image signal output by picking out a light beam incident from the object through a lens apparatus and the filter of the optical apparatus using the sensor; and correct aberration and density unevenness among the plurality of images, based on the array information, wherein each of the cut out plurality of images corresponds to a different area among the plurality of areas of the filter, and wherein the array information includes aberration information for correcting the aberration and density information for correcting the density unevenness among the plurality of images, and the density information is made based on a sensitivity characteristic of the sensor, an optical characteristic of the lens apparatus and transmission characteristics of the optical apparatus.
2 . The apparatus according to claim 1 , wherein the array information includes information is related to a type of the filter.
3 . The apparatus according to claim 1 , wherein the array information includes information related to transmission characteristics of a filter array of the filter and a layout of the plurality of areas.
4 . The apparatus according to claim 1 , wherein the filter is removably insertable into the optical apparatus.
5 . The apparatus according to claim 1 , wherein the filter is disposed in the optical apparatus configured to be detachably attachable to the apparatus.
6 . The apparatus according to claim 1 , wherein the optical apparatus includes a lens array including a plurality of lens units, and wherein the each of the cut out plurality of images corresponds to a different lens unit among the plurality of lens units in the lens array.
7 . The apparatus according to claim 1 , wherein the instructions further cause the apparatus to acquire correction information to be used for the correction of the density unevenness among the plurality of images, based on the array information, and wherein the correction information indicates a ratio of density unevenness of a reference image to another image each included in the plurality of images, and wherein the plurality of images is corrected based on the correction information.
8 . An optical apparatus comprising: a sensor; at least one processor; and at least one memory coupled to the at least one processor, the at least one memory having instructions that, when executed by the at least one processor, cause the optical apparatus to: acquire array information related to the optical apparatus to which a filter that includes a plurality of areas to disperse a light beam from an object into a plurality of spectral components is able to be attached; cut out a plurality of images in a tile form from an image signal output by picking up the light beam incident from the object through a lens apparatus and the filter of the optical apparatus by using the sensor; and correct aberration and density unevenness among the plurality of images, based on the array information, wherein each of the cut out plurality of images corresponds to a different area among the plurality of areas of the filter, and wherein the array information includes aberration information for correcting the aberration and density information for correcting the density unevenness among the plurality of images, and the density information is made based on a sensitivity characteristic of the sensor, an optical characteristic of the lens apparatus and transmission characteristics of the optical apparatus.
9 . The optical apparatus according to claim 8 , wherein the optical apparatus is detachably attachable to a mount portion disposed on the apparatus.
10 . A method to control an apparatus comprising a sensor, the method comprising: acquiring array information related to an optical apparatus to which a filter that includes a plurality of areas to disperse a light beam from an object into a plurality of spectral components is able to be attached; cutting out a plurality of images in a tile form from an image signal output by picking up the light beam incident from the object through a lens apparatus and the filter of the optical apparatus by using the sensor; and correcting aberration and density unevenness among the plurality of images, based on the array information, wherein each of the cut out plurality of images corresponds to a different area among the plurality of areas of the filter, and wherein the array information includes aberration information for correcting the aberration and density information for correcting the density unevenness among the plurality of images, and the density information is made based on a sensitivity characteristic of the sensor, an optical characteristic of the lens apparatus and transmission characteristics of the optical apparatus.
11 . The method according to claim 10 , wherein the array information includes information is related to a type of the filter.
12 . The method according to claim 10 , wherein the array information includes information related to transmission characteristics of a filter array of the filter and a layout of the plurality of areas.
13 . The method according to claim 10 , further comprising acquiring correction information to be used for the correction of the density unevenness among the plurality of images, based on the array information, and wherein the correction information indicates a ratio of density unevenness of a reference image to another image each included in the plurality of images, and wherein the plurality of images is corrected based on the correction information.
14 . The method according to claim 10 , wherein the filter is removably insertable into the optical apparatus.
15 . A non-transitory computer-readable storage medium which stores a program for causing a computer of an apparatus comprising a sensor to execute a method, the method comprising: acquiring array information related to an optical apparatus to which a filter that includes a plurality of areas to disperse a light beam from an object into a plurality of spectral components is able to be attached; cutting out a plurality of images in a tile form from an image signal output by picking up the light beam incident from the object through a lens apparatus and the filter of the optical apparatus by using the sensor; and correcting aberration and density unevenness among the plurality of images, based on the array information, wherein each of the cut out plurality of images corresponds to a different area among the plurality of areas of the filter, and wherein the array information includes aberration information for correcting the aberration and density information for correcting the density unevenness among the plurality of images, and the density information is made based on a sensitivity characteristic of the sensor, an optical characteristic of the lens apparatus and transmission characteristics of the optical apparatus.
16 . The non-transitory computer-readable storage medium according to claim 15 , wherein the array information includes information is related to a type of the filter.
17 . The non-transitory computer-readable storage medium according to claim 15 , wherein the array information includes information related to transmission characteristics of a filter array of the filter and a layout of the plurality of areas.
18 . The non-transitory computer-readable storage medium according to claim 15 , further comprising acquiring correction information to be used for the correction of the density unevenness among the plurality of images, based on the array information, and wherein the correction information indicates a ratio of density unevenness of a reference image to another image each included in the plurality of images, and wherein the plurality of images is corrected based on the correction information.
19 . The non-transitory computer-readable storage medium according to claim 15 , wherein the filter is removably insertable into the optical apparatus.

Description

BACKGROUND Technical Field The aspect of the embodiments relates to an image pickup apparatus for simultaneously picking up a plurality of images using an optical apparatus that is replaceable with respect to the image pickup apparatus as a multispectral camera, a control method for the image pickup apparatus, a storage medium, and an optical apparatus. Description of the Related Art Multispectral cameras, also referred to as multi-band cameras, have been known as cameras configured to capture a plurality of different spectral components in a spectroscopic spectrum. Multispectral cameras are utilized for, for example, food inspection based on images each obtained from a different spectral component. An example of an image pickup system adopted in multispectral cameras is a tiled multispectral filter array having a configuration in which, on a front side (object side) of an image sensor, filters are arranged for respective partial areas (tiles) in a manner corresponding to an image pickup area of an image sensor. The adoption of this system makes it possible to simultaneously acquire a plurality of tiled-form band images (tile images) from the image sensor in one image pickup operation. For example, Japanese Patent Application Laid-Open No. 2020-64164 discusses an optical apparatus that is configured to disperse a light beam into different wavelength bands and includes a replaceable lens array and a replaceable band-pass filter array, and also discusses an image pickup system including the optical apparatus. In the image pickup system discussed in Japanese Patent Application Laid-Open No. 2020-64164, even in a case where spectral characteristics of an object are uniform regardless of a wavelength, there is a possibility that unevenness in brightness (referred to as density unevenness) occurs between different band images. This density unevenness is due to variations in optical characteristics of lenses constituting the lens array, transmission characteristics of each band-pass filter, sensitivity characteristics of the image sensor, and the like. As a technique for reducing the density unevenness, for example, Japanese Patent Application Laid-Open No. 2010-256303 discusses a technique for performing correction processing, based on sensitivity characteristic data obtained in advance, on sensitivity characteristics of an image sensor. However, Japanese Patent Application Laid-Open No. 2010-256303 is considered to have little details on a case where a plurality of band images is obtained using an interchangeable lens apparatus or an optical apparatus including a replaceable filter array. Therefore, in a case where a lens apparatus or an optical apparatus is exchanged with another one, there may be a possibility that the density unevenness between a plurality of band images cannot be accurately corrected. SUMMARY According to an aspect of the embodiments, an apparatus includes a sensor at least one processor, and at least one memory coupled to the at least one processor, the at least one memory having instructions that, when executed by the at least one processor, perform to acquire array information related to an optical apparatus including a filter that includes a plurality of areas to disperse a light beam from an object into a plurality of spectral components, cut out a plurality of images in a tile form from an image signal output by picking out a light beam incident from the object through the filter of the optical apparatus using the sensor; and correct brightness of the plurality of images, based on the array information, wherein the each of plurality of images corresponds to a different area among the plurality of areas of the filter. Further features of the embodiments will become apparent from the following description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram illustrating a configuration example of an image pickup apparatus according to a first exemplary embodiment of the disclosure. FIGS. 2A to 2C are diagrams each illustrating an image pickup system according to the first exemplary embodiment. FIG. 3 is a flowchart illustrating aberration correction processing according to the first exemplary embodiment. FIGS. 4A to 4D are diagrams each illustrating a method for cutting out tile images and performing aberration correction processing on the tile images according to the first exemplary embodiment. FIG. 5 is a flowchart illustrating density correction processing according to a second exemplary embodiment of the disclosure. DESCRIPTION OF THE EMBODIMENTS (Basic Configuration of Image Pickup Apparatus 1) Exemplary embodiments of the disclosure will be described below with reference to the accompanying drawings. FIG. 1 is a block diagram illustrating a configuration example of an image pickup apparatus 1 according to a first exemplary embodiment of the disclosure. One or more functional blocks illustrated in FIG. 1 may be