# US 2021/0241693 A1 · Temperature based oled sub-pixel luminosity correction > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0241693 A1 - Document ID: US20210241693A1 - Status: Published application - Kind: A1 - Application number: 17/048,692 - Filed: 2018-09-26 - Published: 2021-08-05 - Earliest claimed: 2018-09-26 - Assignees: Hewlett-Packard Development Company, L.P. - Applicants: Hewlett-Packard Development Company, L.P. - Inventors: Hsing-Hung Hsieh; Cheng-Hua Yu; Ann Alejandro Villegas - Web page: https://patentgrep.com/patent/US20210241693A1 ## CPC - G09G 3/3225: using an active matrix - G09G 3/3258: with pixel circuitry controlling the voltage across the light-emitting element - G01K 1/026: {arrangements for monitoring a plurality of temperatures, e.g. by multiplexing} - G01K 13/00: Thermometers specially adapted for specific purposes - G09G 2320/041: Temperature compensation - G09G 2320/048: using evaluation of the usage time - G09G 2360/16: Calculation or use of calculated indices related to luminance levels in display data - G09G: ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION (arrangements for transferring data between digital computers and displays G06F3/14; static indicating arrangements comprising an association of a number of separate sources or light control cells G09F9/00; static indicating arrangements comprising integral associations of a number of light sources H01J, H01K, H10H, H05B33/12; scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission, details thereof H04N1/00) - G01K: MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR (radiation pyrometry G01J5/00) ## Abstract In an example implementation according to aspects of the present disclosure, a system including a controller to receive a temperature value, from a temperature sensor corresponding to a sub-pixel in an organic light emitting display. The controller calculates a luminous value of the sub-pixel based on the temperature value and a function corresponding to a degradation of luminosity over time and temperature. The controller determines, based on the luminous value, a corrected luminous value corresponding to a target luminous value. The controller retrieves a voltage value from a second database, wherein the second database comprises a luminous-voltage relationship. The controller applies the voltage value to the sub-pixel. ## Claims ### Claim 1 A system comprising: an organic light emitting diode display, wherein the display is an array of sub-pixels; a temperature sensor disposed proximally to a sub-pixel selected from the array of sub-pixels; a controller communicatively coupled to the temperature sensor, the controller to: receive a temperature value corresponding to a sub-pixel; determine a luminous value of the sub-pixel based on the temperature value and a database corresponding to luminosity over time and temperature; determine, based on the luminous value, a corrected luminous value corresponding to a target luminous value; determine a voltage value based on the corrected luminous value and the luminous value; and apply the voltage value to the sub-pixel. ### Claim 2 (depends on 1) The system of claim 1, wherein the temperature sensor is disposed at an edge of the display and the received temperature value is based on an interpolation between a first temperature value from the temperature sensor and a second temperature value from a second temperature sensor disposed on the display. ### Claim 3 (depends on 2) The system of claim 2, wherein the second temperature sensor is disposed on the opposite edge of the display from the temperature sensor. ### Claim 4 (depends on 1) The system of claim 1, wherein the database comprises historical measured values of luminosity over time and temperature. ### Claim 5 (depends on 1) The system of claim 1, wherein the database comprises functional extrapolated values of luminosity over time and temperature. ### Claim 6 (depends on 1) The system of claim 1, wherein the controller is to: retrieve the voltage from a second database to determine the voltage, wherein the second database comprises a luminous-voltage relationship. ### Claim 7 A method comprising: receiving a temperature value, from a temperature sensor corresponding to a sub-pixel in an organic light emitting display; calculating a luminous value of the sub-pixel based on the temperature value and a function corresponding to a degradation of luminosity over time and temperature; determining, based on the luminous value, a corrected luminous value corresponding to a target luminous value; retrieving a voltage value from a database, wherein the database comprises a luminous-voltage relationship; and applying the voltage value to the sub-pixel. ### Claim 8 (depends on 7) The method of claim 7, wherein the temperature sensor is disposed at an edge of the display and the received temperature value is based on an interpolation between a first temperature value from the temperature sensor and a second temperature value from a second temperature sensor disposed on the display. ### Claim 9 (depends on 8) The method of claim 8, wherein the second temperature sensor is disposed on the opposite edge of the display from the temperature sensor. ### Claim 10 (depends on 9) The method of claim 9, wherein the temperature sensor and the second temperature sensor are disposed outside the perimeter of the display. ### Claim 11 (depends on 7) The method of claim 7, wherein the degradation function comprises a curve function based on historical measured values of luminosity over time and temperature. ### Claim 12 (depends on 7) The method of claim 7, wherein the database comprises functional extrapolated values of luminosity over time and temperature. ### Claim 13 A computing device comprising: a controller; a memory, communicatively coupled to the controller, having instructions stored thereon that when executed cause the controller to: receive a temperature value from a temperature sensor corresponding to a sub-pixel; retrieve from a database a luminous value of the sub-pixel based on the temperature value; determine, based on the luminous value, a corrected luminous value corresponding to a target luminous value; retrieve a voltage value based on the corrected luminous value and the luminous value from a second database, wherein the second database comprises a luminous-voltage relationship; and apply the voltage value to the sub-pixel. ### Claim 14 (depends on 13) The computing device of claim 13, wherein the temperature sensor is disposed at an interior to an edge of the display and the received temperature value is based on an interpolation between a first temperature value from the temperature sensor and a second temperature value from a second temperature sensor disposed on the display. ### Claim 15 (depends on 13) The computing device of claim 13, wherein the second temperature sensor is disposed on interior to the edge of the display from the temperature sensor.