# US 9,753,396 B2 · Image reproduction system including a cooling unit for cooling light emitting units and method for using system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,753,396 B2 - Document ID: US9753396B2 - Status: Granted - Kind: B2 - Application number: 14/985,640 - Filed: 2015-12-31 - Published: 2016-07-14 - Granted: 2017-09-05 - Earliest claimed: 2015-01-14 - Assignees: Xeikon Manufacturing N.V. - Applicants: Xeikon Manufacturing N.V. - Inventors: Herman Jan Godelieve Van De Straete; Jurgen Norbert Bart Devlieghere - Web page: https://patentgrep.com/patent/US9753396B2 ## CPC - G03G 15/04054: {by LED arrays} - B41J 2/45: using light-emitting diode {[LED] or laser} arrays - B41J 29/377: Cooling or ventilating arrangements - F21V 29/00: Protecting lighting devices from thermal damage; Cooling or heating arrangements specially adapted for lighting devices or systems (lighting fixtures combined with outlets for air-treatment systems F24F13/078) - G03G 21/20: Humidity or temperature control {also ozone evacuation; Internal apparatus environment control} - G03G 2215/0409: Light-emitting diodes, i.e. LED-array - G03G: ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY - B41J: TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS - F21V: FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR ## Abstract A system for use in image reproduction, the system includes at least a first light emitting unit and a second light emitting unit. The first light emitting unit includes a first cooling means arranged for cooling the first light emitting unit. The second light emitting unit includes a second cooling means arranged for cooling the second light emitting unit independently of the first light emitting unit. The first light emitting unit has a first elongate emitting area. The second light emitting unit has a second elongate emitting area. A control unit controls the cooling of at least one of the first cooling means and the second cooling means such that at least one of the first elongate emitting area and the second elongate emitting area, respectively, has a desired length. ## Claims ### Claim 1 A system for use in image reproduction, said system comprising: at least a first light emitting unit and a second light emitting unit; said first light emitting unit comprising a first cooling means arranged for cooling said first light emitting unit; said second light emitting unit comprising a second cooling means arranged for cooling said second light emitting unit independently of said first light emitting unit; said first light emitting unit having a first elongate emitting area; said second light emitting unit having a second elongate emitting area; a control unit configured for controlling the cooling of at least one of said first cooling means and said second cooling means such that, when the first and second light emitting units have a different length at a same temperature, the first and second light emitting units are controlled to be at different temperatures, leading to a different expansion thereof which is controlled such that the lengths thereof are substantially equal. ### Claim 2 (depends on 1) The system of claim 1, wherein the control unit is configured for controlling the cooling of at least one of said first cooling means and said second cooling means such that |L1−L2|<60 micron, preferably |L1−L2|<40 micron, or more preferably |L1−L2|<30 micron, wherein L1 is the length of said first elongate light emitting area and L2 the length of said second elongate light emitting area. ### Claim 3 (depends on 1) The system of claim 1, further comprising a measurement device configured for measuring at least one measure representative for a difference between a first and second length of the first and second elongate light emitting area, respectively; wherein said control unit is configured for controlling the cooling of at least one of said first cooling means and said second cooling means based on said at least one measure. ### Claim 4 (depends on 2) The system of claim 2, further comprising a measurement device configured for measuring at least one measure representative for a difference between a first and second length of the first and second elongate light emitting area, respectively; wherein said control unit is configured for controlling the cooling of at least one of said first cooling means and said second cooling means based on said at least one measure. ### Claim 5 (depends on 4) The system of claim 4, wherein said measurement device comprises a left and right measurement unit for measuring a first set of positions of a left and right boundary of the first elongate light emitting area and a second set of positions of a left and right boundary of the second elongate light emitting area; said first set and said second set being said at least one measure. ### Claim 6 (depends on 4) The system of claim 4, wherein said measurement device comprises any one of the following: a camera, an optical density sensor, an interference pattern measurement device, a spectrograph measurement device. ### Claim 7 (depends on 1) The system of claim 1, further comprising a first temperature sensor for measuring a first temperature of the first light emitting unit and a second temperature sensor for measuring a second temperature of the second light emitting unit; said control circuit being further configured for controlling at least one of the first cooling means and the second cooling means in function of the measured first and second temperature. ### Claim 8 (depends on 1) The system of claim 1, wherein said first light emitting unit comprises a first carrier on which a first plurality of light emitting array ICs is arranged, and wherein said first cooling means is arranged for cooling said first carrier; wherein said second light emitting unit comprises a second carrier on which a second plurality of light emitting array ICs is arranged, and wherein said second cooling means is arranged for cooling said second carrier. ### Claim 9 (depends on 8) The system of claim 8, wherein the control unit is configured for determining a suitable temperature of at least one of the first carrier and the second carrier in function of a desired length of at least one of the first elongate light emitting area and the second elongate light emitting area; and for controlling at least one of the first cooling means and the second cooling means such that at least one of the first carrier and the second carrier is at the determined suitable temperature. ### Claim 10 (depends on 8) The system of claim 8, wherein the first carrier comprises a heat sink of the first cooling means, and the second carrier comprises a heat sink of the second cooling means. ### Claim 11 (depends on 8) The system of claim 8, wherein the first cooling means comprises: a liquid cooling circuit arranged for cooling the first carrier with liquid; an air cooler for cooling said liquid; and a sensor for measuring a temperature of the liquid; wherein the control unit is configured for regulating the air cooler such that said first elongate light emitting area has a desired length. ### Claim 12 A method for controlling an image reproduction system comprising at least a first light emitting unit and a second light emitting unit, said first light emitting unit having a first elongate light emitting area; said second light emitting unit having a second elongate light emitting area; said method comprising: actively cooling said first light emitting unit; actively cooling said second light emitting unit independently of said first light emitting unit; controlling at least one of actively cooling said first light emitting unit and actively cooling said second light emitting unit, such that, when the first and second light emitting units have a different length at a same temperature, the first and second light emitting units are controlled to be at different temperatures, leading to a different expansion thereof which is controlled such that the lengths thereof are substantially equal. ### Claim 13 (depends on 12) The method of claim 12, wherein the controlling comprises controlling at least one of actively cooling said first light emitting unit and actively cooling said second light emitting unit such that |L1−L2|<60 micron, preferably |L1−L2|<40 micron, or more preferably |L1−L2|<30 micron, wherein L1 is the length of said first elongate light emitting area and L2 the length of said second elongate light emitting area. ### Claim 14 (depends on 12) The method of claim 12, further comprising: measuring at least one measure representative for a difference between a first and second length of the first and second elongate light emitting area, respectively; wherein the controlling comprises controlling at least one of actively cooling said first light emitting unit and actively cooling said second light emitting unit based on said at least one measure. ### Claim 15 (depends on 12) A computer program product comprising computer-executable instructions for performing one or more steps of the method of claim 12, when the program is run on a computer. ### Claim 16 A system for use in image reproduction, said system comprising: at least a first light emitting unit and a second light emitting unit; said first light emitting unit comprising a first cooling means arranged for cooling said first light emitting unit; said second light emitting unit comprising a second cooling means arranged for cooling said second light emitting unit independently of said first light emitting unit; said first light emitting unit having a first elongate emitting area; said second light emitting unit having a second elongate emitting area; a measurement device configured for measuring at least one measure representative of a difference between a first and second length of the first and second elongate light emitting area, respectively; a control unit configured for controlling the cooling of at least one of said first cooling means and said second cooling means based on said at least one measure; wherein said measurement device comprises any one of the following: a camera, an optical density sensor, an interference pattern measurement device, a spectrograph measurement device. ### Claim 17 (depends on 16) The system of claim 16, further comprising a first temperature sensor for measuring a first temperature of the first light emitting unit and a second temperature sensor for measuring a second temperature of the second light emitting unit; said control circuit being further configured for controlling at least one of the first cooling means and the second cooling means in function of the measured first and second temperature. ### Claim 18 (depends on 16) The system of claim 16, wherein the control unit is configured for controlling the cooling of at least one of said first cooling means and said second cooling means such that, when the first and second light emitting units have a different length at a same temperature, the first and second light emitting units are controlled to be at different temperatures, leading to a different expansion thereof which is controlled such that the lengths thereof are substantially equal. ### Claim 19 (depends on 16) The system of claim 16, wherein the control unit is configured for controlling the cooling of at least one of said first cooling means and said second cooling means such that |L1−L2|<60 micron, preferably |L1−L2|<40 micron, or more preferably |L1−L2|<30 micron, wherein L1 is the length of said first elongate light emitting area and L2 the length of said second elongate light emitting area.