# US 10,121,413 B2 · Display device and driving method thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,121,413 B2 - Document ID: US10121413B2 - Status: Granted - Kind: B2 - Application number: 14/858,348 - Filed: 2015-09-18 - Published: 2016-03-24 - Granted: 2018-11-06 - Earliest claimed: 2014-09-18 - Assignees: Japan Display Inc. - Applicants: Japan Display Inc. - Inventors: Tetsuo Morita; Hiroyuki Kimura; Makoto Shibusawa; Hiroshi Nakayama; Hiroshi Tabatake; Yutaka Umeda - Web page: https://patentgrep.com/patent/US10121413B2 ## CPC - G09G 3/3233: with pixel circuitry controlling the current through the light-emitting element - G09G 2300/0861: with additional control of the display period without amending the charge stored in a pixel memory, e.g. by means of additional select electrodes - G09G 2310/0245: Clearing or presetting the whole screen independently of waveforms, e.g. on power-on (G09G2310/063 takes precedence) - G09G 2330/021: Power management, e.g. power saving - G09G 2330/025: Reduction of instantaneous peaks of current - G09G 2330/026: Arrangements or methods related to booting a display - 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) ## Abstract A flash phenomenon of OLEDs at the time of power source ON of a display device is suppressed. The OLED emits light when reference potentials VSS and VDD are applied from power source lines to the OLED's cathode and anode respectively. While the anode can be connected to one of the power source line via a driving TFT and a lighting switch, a reset potential VRS can be applied to the anode via a reset switch and the driving TFT. The lighting switch is turned OFF and the reset switch and the driving TFT are turned ON so that VRS is applied to the anode, before starting the application of the reference potentials to the power source lines. Following this state, the application of the reference potentials to the power source lines starts, and thus a normal operation of allowing the OLED to emit light starts. ## Claims ### Claim 1 A display device, comprising: a light emitting element emitting light by applying a voltage between electrodes; a first power source line applied with a first reference potential which is supplied to one electrode of the light emitting element; a second power source line applied with a second reference potential which allows the light emitting element to emit light; a driving transistor controlling an amount of current between a first current terminal which is connected to the other electrode of the light emitting element and a second current terminal which is connected to the second power source line according to a control voltage signal; a first switching element switching connection and disconnection between the second power source line and the second current terminal; a second switching element switching the presence or absence of application of a reset potential to the second current terminal from a reset power source; and a control unit executing a power source ON sequence, wherein the driving transistor is an n-channel type transistor, the second reference potential is higher than the first reference potential, the reset potential has a potential difference which is less than a light emission starting voltage of the light emitting element to the first reference potential, and the power source ON sequence controls the first switching element so as to block between the driving transistor and the second power source line, and controls the second switching element and the driving transistor so as to set a preset state in which the other electrode of the light emitting element is connected to the reset power source, before starting the application of each of the reference potentials to the first power source line and the second power source line, and starts the application of each of the reference potentials to the first power source line and the second power source line in the preset state, thereby setting a ready state in which a normal operation of allowing the light emitting element to emit light is able to be performed. ### Claim 2 (depends on 1) The display device according to claim 1, wherein the first switching element is configured as a transistor having the same polarity as that of the driving transistor, and the second switching element are configured as another transistor having the same polarity as that of the driving transistor. ### Claim 3 A display device, comprising: a light emitting element disposed in each of a plurality of pixels which are arranged in a plurality of rows and emitting light by applying a voltage between electrodes; a first power source line applied with a first reference potential which is supplied to one electrode of the light emitting element; a second power source line applied with a second reference potential which allows the light emitting element to emit light; a driving transistor disposed in each of the pixels and controlling an amount of current between a first current terminal which is connected to the other electrode of the light emitting element of the pixel and a second current terminal which is connected to the second power source line according to a control voltage signal; at least one first switching element switching connection and disconnection between the second power source line and the second current terminal of a plurality of the driving transistors which are arranged in each of pixel rows; at least one second switching element switching the presence or absence of application of a reset potential from a reset power source to the second current terminal of a plurality of the driving transistors which are arranged in each of the pixel rows; and a control unit executing a power source ON sequence, wherein: the driving transistor is an n-channel type transistor, the second reference potential is higher than the first reference potential, the reset potential has a potential difference which is less than a light emission starting voltage of the light emitting element to the first reference potential, and the power source ON sequence controls the first switching element so as to block between the driving transistor and the second power source line, and controls the second switching element and the driving transistor so as to set a preset state in which the other electrode of the light emitting element is connected to the reset power source, before starting the application of each of the reference potentials to the first power source line and the second power source line, in each of the pixel rows, starts the application of each of the reference potentials to the first power source line and the second power source line in the preset state, and then sequentially controls the second switching element for each of the pixel rows in synchronization with a raster scan so as to stop the supply of the reset potential to the other electrode of the light emitting element, and performs an operation of allowing the light emitting element of the pixel row to emit light. ### Claim 4 (depends on 3) The display device according to claim 3, wherein the first switching element is configured as a transistor having the same polarity as that of the driving transistor, and the second switching element are configured as another transistor having the same polarity as that of the driving transistor. ### Claim 5 A driving method of a display device which includes a light emitting element emitting light by applying a voltage between electrodes, a first power source line applied with a first reference potential which is supplied to one electrode of the light emitting element, a second power source line applied with a second reference potential which allows the light emitting element to emit light, a driving transistor controlling an amount of current between a first current terminal which is connected to the other electrode of the light emitting element and a second current terminal which is connected to the second power source line according to a control voltage signal, a first switching element switching connection and disconnection between the second power source line and the second current terminal, and a second switching element switching the presence or absence of application of a reset potential to the second current terminal from a reset power source, wherein: the driving transistor is an n-channel type transistor; the second reference potential is higher than the first reference potential; and the reset potential has a potential difference which is less than a light emission starting voltage of the light emitting element to the first reference potential, the method comprising: controlling the first switching element so as to block between the driving transistor and the second power source line, and controlling the second switching element and the driving transistor so as to set a preset state in which the other electrode of the light emitting element is connected to the reset power source, before starting the application of each of the reference potentials to the first power source line and the second power source line; and starting the application of each of the reference potentials to the first power source line and the second power source line in the preset state, and setting a ready state in which a normal operation of allowing the light emitting element to emit light is able to be performed.