# US 2019/0356892 A1 · Imaging apparatus and method of calculating white balance gain > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0356892 A1 - Document ID: US20190356892A1 - Status: Published application - Kind: A1 - Application number: 16/412,188 - Filed: 2019-05-14 - Published: 2019-11-21 - Earliest claimed: 2018-05-21 - Assignees: Olympus Corporation - Applicants: Olympus Corporation - Inventors: Shinya TAKASUMI - Web page: https://patentgrep.com/patent/US20190356892A1 ## CPC - H04N 1/6027: {Correction or control of colour gradation or colour contrast (H04N1/6058 takes precedence)} - H04N 23/88: for colour balance, e.g. white-balance circuits or colour temperature control - H04N 23/12: with one sensor only - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract An interchangeable-lens imaging apparatus includes a color-temperature-information calculation circuit and a white-balance-gain calculation circuit. The color-temperature-information calculation circuit calculates color-temperature information on the basis of a first white balance gain associated with a first lens unit and first lens information of the first lens unit. The first white balance gain is calculated on the basis of a signal output from an image sensor. The white-balance-gain calculation circuit calculates a second white balance gain associated with a second lens unit that is different from the first lens unit on the basis of the color-temperature information and second lens information acquired from the second lens unit. ## Claims ### Claim 1 An interchangeable-lens imaging apparatus comprising: an image sensor; a color-temperature-information calculation circuit that calculates color-temperature information on the basis of a first white balance gain associated with a first lens unit and first lens information of the first lens unit, the first white balance gain being calculated on the basis of a signal output from the image sensor; and a white-balance-gain calculation circuit that calculates a second white balance gain associated with a second lens unit that is different from the first lens unit on the basis of the color-temperature information and second lens information acquired from the second lens unit. ### Claim 2 (depends on 1) The interchangeable-lens imaging apparatus of claim 1, wherein the image sensor detects light rays having a plurality of colors in a manner such that these colors are capable of being distinguished from each other, the first white balance gain includes a plurality of first white-balance-gain components that correspond to the plurality of colors, the color-temperature information includes a plurality of color-temperature-information components that correspond to the plurality of colors, and the color-temperature-information calculation circuit calculates the plurality of color-temperature-information components on the basis of the plurality of first white-balance-gain components and the first lens information. ### Claim 3 (depends on 2) The interchangeable-lens imaging apparatus of claim 2, wherein the second white balance gain includes a plurality of second white-balance-gain components that correspond to the plurality of colors, and the white-balance-gain calculation circuit calculates the plurality of second white-balance-gain components on the basis of the plurality of color-temperature-information components and the second lens information. ### Claim 4 (depends on 2) The interchangeable-lens imaging apparatus of claim 2, wherein the plurality of color-temperature-information components are each an reciprocal color temperature. ### Claim 5 (depends on 1) The interchangeable-lens imaging apparatus of claim 1, further comprising: a white-balance correction circuit that corrects a white balance of image data, wherein the white-balance correction circuit corrects a white balance of image data generated from image shooting performed with the first lens unit on the basis of the first white balance gain, and corrects a white balance of image data generated from image shooting performed with the second lens unit on the basis of the second white balance gain. ### Claim 6 (depends on 1) The interchangeable-lens imaging apparatus of claim 1, further comprising: a display that displays a color temperature of a light source on the basis of the color-temperature information calculated by the color-temperature-information calculation circuit. ### Claim 7 An interchangeable-lens imaging apparatus comprising: an image sensor; a color-temperature-information calculation circuit that calculates color-temperature information on the basis of a first white balance gain associated with a first lens unit and first lens information of the first lens unit, the first white balance gain being calculated on the basis of a signal output from the image sensor; and a display that displays a color temperature of a light source on the basis of the color-temperature information calculated by the color-temperature-information calculation circuit. ### Claim 8 A white-balance-gain calculation method implemented by an interchangeable-lens imaging apparatus that includes an image sensor, the white-balance-gain calculation method comprising: calculating color-temperature information on the basis of first lens information of a first lens unit and a first white balance gain associated with the first lens unit that is calculated on the basis of a signal output from the image sensor; and calculating a second white balance gain associated with a second lens unit that is different from the first lens unit on the basis of the color-temperature information and second lens information acquired from the second lens unit. ### Claim 9 (depends on 8) The white-balance-gain calculation method of claim 8, wherein the first white balance gain includes a plurality of first white-balance-gain components that correspond to a plurality of colors, the color-temperature information includes a plurality of color-temperature-information components that correspond to the plurality of colors, the white-balance-gain calculation method further comprises detecting, by the image sensor, light rays having the plurality of colors in a manner such that these colors are capable of being distinguished from each other, and the calculating of the color-temperature information includes calculating the plurality of color-temperature-information components on the basis of the plurality of first white-balance-gain components and the first lens information. ### Claim 10 (depends on 9) The white-balance-gain calculation method of claim 9, wherein the second white balance gain includes a plurality of second white-balance-gain components that correspond to the plurality of colors, and the calculating of the second white balance gain includes calculating the plurality of second white-balance-gain components on the basis of the plurality of color-temperature-information components and the second lens information. ### Claim 11 (depends on 9) The white-balance-gain calculation method of claim 9, wherein the plurality of color-temperature-information components are each an reciprocal color temperature. ### Claim 12 (depends on 8) The white-balance-gain calculation method of claim 8, further comprising: correcting a white balance of image data generated from image shooting performed with the first lens unit on the basis of the first white balance gain; and correcting a white balance of image data generated from image shooting performed with the second lens unit on the basis of the second white balance gain. ### Claim 13 (depends on 8) The white-balance-gain calculation method of claim 8, further comprising: displaying a color temperature of a light source on the basis of the color-temperature information calculated by the color-temperature-information calculation circuit.