# US 2017/0257541 A1 · Lighting device that controls light emission while suppressing temperature rise, image pickup apparatus, and method of controlling lighting device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0257541 A1 - Document ID: US20170257541A1 - Status: Published application - Kind: A1 - Application number: 15/446,854 - Filed: 2017-03-01 - Published: 2017-09-07 - Earliest claimed: 2016-03-03 - Assignees: Canon Kabushiki Kaisha - Applicants: Canon Kabushiki Kaisha - Inventors: Keiichiro Saito - Web page: https://patentgrep.com/patent/US20170257541A1 ## CPC - H04N 23/56: provided with illuminating means - G03B 15/05: Combinations of cameras with electronic flash apparatus; Electronic flash units - H05B 41/325: {by measuring the incident light} - H05B 41/39: continuously - H05B 47/125: by using cameras - G03B 2215/0592: installed in front of light emitter - Y02B 20/40: Control techniques providing energy savings, e.g. smart controller or presence detection - 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) - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS ## Abstract A lighting device capable of performing satisfactory light emission control while suppressing a rise in the temperature of the lighting device irrespective of the attachment of an optical accessory. In the lighting device, an accessory detection section detects whether or not an optical accessory for color adjustment or light distribution angle adjustment is attached to a light emission section, and light emission performed by the light emission section is limited based on a result of detection performed by the accessory detection section. ## Claims ### Claim 1 A lighting device comprising: a light emission unit; a detection unit configured to detect whether or not an optical accessory for color adjustment or light distribution angle adjustment is attached to said light emission unit; and a control unit configured to limit light emission performed by said light emission unit based on a result of detection by said detection unit. ### Claim 2 (depends on 1) The lighting device according to claim 1, wherein said control unit calculates a temperature of a target site according to heat generated by light emission performed by said light emission unit, and limits light emission performed by said light emission unit based on the temperature of the target site. ### Claim 3 (depends on 1) The lighting device according to claim 1, wherein said control unit limits light emission performed by said light emission unit according to a number of times of continuous light emission performed by said light emission unit. ### Claim 4 (depends on 1) The lighting device according to claim 1, wherein said light emission unit is held such that a position thereof relative to the g target site can be changed, and wherein said control unit limits light emission performed by said light emission unit based on the relative position between said light emission unit and the target site. ### Claim 5 (depends on 4) The lighting device according to claim 4, wherein said control unit limits light emission performed by said light emission unit based on a threshold value for controlling a light emission interval or charging current according to the relative position between said light emission unit and the target site. ### Claim 6 (depends on 5) The lighting device according to claim 5, wherein said control unit changes the threshold value based on a result of detection by said detection unit. ### Claim 7 A lighting device comprising: a light source; a detection unit configured to detect that a specific optical accessory for changing characteristics of light irradiated from said light source is attached; and a suppression unit configured to perform processing for suppressing a temperature rise of the lighting device, based on a result of detection by said detection unit. ### Claim 8 (depends on 7) The lighting device according to claim 7, wherein said suppression unit performs processing for suppressing the temperature rise of the lighting device according to a total of values each added according to light emission from said light source, and makes a value added according to light emission from said light source larger in a case where said detection unit detects that the specific optical accessory is attached than in a case where said detection unit does not detect that the specific optical accessory is attached. ### Claim 9 (depends on 8) The lighting device according to claim 8, further comprising: an optical panel, and an irradiation angle change unit configured to change an irradiation angle of light irradiated from said light source by changing a relative position between said light source and said optical panel, and wherein said suppression unit sets a threshold value for switching the processing for suppressing the temperature rise, based on the relative position. ### Claim 10 (depends on 9) The lighting device according to claim 9, wherein said suppression unit makes larger the value added according to light emission from said light source, as said light source and said optical panel are closer to each other. ### Claim 11 (depends on 7) The lighting device according to claim 7, further comprising a temperature sensor for measuring a temperature of the lighting device, and wherein said suppression unit performs the processing for suppressing the temperature rise according to the temperature measured by said temperature sensor, and makes a threshold value for switching the processing for suppressing the temperature rise lower in a case where said detection unit detects that the specific optical accessory is attached than in a case where said detection unit does not detect that the specific optical accessory is attached. ### Claim 12 (depends on 7) The lighting device according to claim 7, wherein said suppression unit makes a number of times of continuous light emission allowed to be executed smaller in a case where said detection unit detects that the specific optical accessory is attached than in a case where said detection unit does not detect that the specific optical accessory is attached. ### Claim 13 (depends on 7) The lighting device according to claim 7, wherein said suppression unit makes a total light emission amount of continuous light emission smaller in a case where said detection unit detects that the specific optical accessory is attached than in a case where said detection unit does not detect that the specific optical accessory is attached. ### Claim 14 (depends on 7) The lighting device according to claim 7, wherein said suppression unit makes longer a time period during which light emission from said light source is inhibited, as the processing for suppressing the temperature rise. ### Claim 15 (depends on 7) The lighting device according to claim 7, wherein said suppression unit makes smaller charging current supplied to a capacitor that accumulates electric energy for causing light emission from said light source, as the processing for suppressing the temperature rise. ### Claim 16 An image pickup apparatus including: an image pickup unit configured to perform image pickup of an object via an image pickup optical system to thereby obtain an image, and a lighting device, wherein said lighting device comprises: a light emission unit; a detection unit configured to detect whether or not an optical accessory for color adjustment or light distribution angle adjustment is attached to said light emission unit; and a control unit configured to limit light emission performed by said light emission unit based on a result of detection by said detection unit. ### Claim 17 An image pickup apparatus including: an image pickup unit configured to perform image pickup of an object via an image pickup optical system to thereby obtain an image, and a lighting device, wherein said lighting device comprises: a light source; a detection unit configured to detect that a specific optical accessory for changing characteristics of light irradiated from said light source is attached; and a suppression unit configured to perform processing for suppressing a temperature rise of said lighting device, based on a result of detection by said detection unit. ### Claim 18 A method of controlling a lighting device, comprising: detecting whether or not an optical accessory for color adjustment or light distribution angle adjustment is attached to a light emission unit, by a detection unit; and limiting light emission performed by the light emission unit based on a result of detection by the detection unit, by a control unit. ### Claim 19 A method of controlling a lighting device, comprising: detecting that a specific optical accessory for changing characteristics of light irradiated from a light source is attached, by a detection unit; and performing processing for suppressing a temperature rise of the lighting device, based on a result of detection by the detection unit, by a suppression unit.