# US 11,308,884 B2 · Display device, method of display driving, and non-transitory computer-readable medium

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 11,308,884 B2
- Document ID: US11308884B2
- Status: Granted
- Kind: B2
- Application number: 17/396,994
- Filed: 2021-08-09
- Published: 2022-02-24
- Granted: 2022-04-19
- Earliest claimed: 2020-08-20
- Assignees: Sharp Kabushiki Kaisha
- Applicants: Sharp Kabushiki Kaisha
- Inventors: Fumitaka Seki; Kenji Maeda; Takuya Okamoto; Shinji Yamamoto; Yuichi Sato; Masafumi Ito; Yohichi Takazane
- Web page: https://patentgrep.com/patent/US11308884B2

## CPC

- G09G 3/3233: with pixel circuitry controlling the current through the light-emitting element
- G09G 3/2096: {Details of the interface to the display terminal specific for a flat panel (suitable for both CRT and flat panel G09G5/006; specific for a CRT G09G1/167)}
- G09G 3/3258: with pixel circuitry controlling the voltage across the light-emitting element
- G09G 2300/0417: Special arrangements specific to the use of low carrier mobility technology
- G09G 2300/0842: forming a memory circuit, e.g. a dynamic memory with one capacitor
- G09G 2310/04: Partial updating of the display screen
- G09G 2320/0247: Flicker reduction other than flicker reduction circuits used for single beam cathode-ray tubes
- G09G 2320/0626: for control of overall brightness
- G09G 2320/103: Detection of image changes, e.g. determination of an index representative of the image change
- G09G 2330/021: Power management, e.g. power saving
- G09G 2340/0435: Change or adaptation of the frame rate of the video stream
- G09G 2360/16: Calculation or use of calculated indices related to luminance levels in display data
- G09G 2370/22: Detection of presence or absence of input display information or of connection or disconnection of a corresponding information source
- H10K 59/12: Active-matrix OLED [AMOLED] displays
- 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)
- H10K: ORGANIC ELECTRIC SOLID-STATE DEVICES

## Abstract

A display device includes: a display unit; a display driver configured to drive the display unit; and a display-data generator configured to transfer a screenful of update display data to the display driver. The display driver includes a light-emission controller configured to control self-luminous elements to emit light, and a memory storing a screenful of the update display data. After a lapse of a predetermined time period from a driving stop time, the display driver reads the update display data stored in the memory and then uses the update display data to drive a screen, the driving stop time being a time when the display unit is stopped from driving based on the update display data. The display driver causes the self-luminous elements of the display unit to emit light, even during a display update or no display update performed on the display driver by the display-data generator.

## Claims

### Claim 1

A display device comprising:
a display unit having a screen with self-luminous elements arranged;
a display driver configured to drive the display unit so that the display unit performs display based on display data onto the screen; and
a display-data generator configured to, upon an update of the display data, transfer a screenful of update display data to the display driver,
wherein the display driver includes
a light-emission controller configured to control the self-luminous elements to emit light, and
a memory storing a screenful of the update display data,
after a lapse of a predetermined time period from a driving stop time, the display driver reads the update display data stored in the memory and then uses the update display data to drive the screen, the driving stop time being a time when the display unit is stopped from driving based on the update display data, and
the display driver causes the self-luminous elements of the display unit to emit light, even during a display update or no display update performed on the display driver by the display-data generator.

### Claim 2 (depends on 1)

The display device according to claim 1, wherein
the display driver starts driving the display unit in accordance with the update display data during transfer of the update display data from the display-data generator to the display driver.

### Claim 3 (depends on 1)

The display device according to claim 1, wherein
the display device performs, at least once in a pause frame, driving without a data rewrite.

### Claim 4 (depends on 1)

The display device according to claim 1, wherein
the display-data generator includes
an image determining unit configured to determine whether a ratio of a pixel in a predetermined image region is equal to or greater than a threshold, the pixel having a gradation falling within a gradation range that is equal to or greater than a first gradation and is equal to or smaller than a second gradation, the first gradation not being a minimum gradation, the second gradation not being a maximum gradation,
a drive changer configured to determine a refresh rate of the display device in accordance with a resultant determination made by the image determining unit, and
a determination unit configured to determine a level of voltage that is to be used in driving without a data rewrite, or to determine a period of how long the voltage is to be applied, and
the determination unit determines the level of the voltage that is to be used in the driving without a data rewrite, or determines the period of how long the voltage is to be applied.

### Claim 5 (depends on 4)

The display device according to claim 4, wherein
the determination unit determines the level, the period, or the refresh rate in accordance with a property of an individual included in the display device.

### Claim 6 (depends on 4)

The display device according to claim 4, wherein
the determination unit determines the level, the period, or the refresh rate in accordance with a temperature of the display unit included in the display device.

### Claim 7 (depends on 4)

The display device according to claim 4, wherein
the determination unit determines the level, the period, or the refresh rate in accordance with a brightness level.

### Claim 8 (depends on 1)

The display device according to claim 1, wherein
a refresh rate in no update to the display data is set at equal to or smaller than a maximum drive-enabled frequency, the refresh rate indicating a frequency of how often a display content on the screen is to be updated based on the update display data after a lapse of a predetermined time period.

### Claim 9 (depends on 1)

The display device according to claim 1, wherein
the self-luminous elements include an organic light emitting diode.

### Claim 10 (depends on 1)

The display device according to claim 1, wherein
the display unit has switching elements corresponding to the self-luminous elements, and
the switching elements include a thin-film transistor composed of an oxide semiconductor using In, Ga, and Zn.

### Claim 11

A method of display driving that is performed by a display driver that drives a display unit having a screen so that the display unit performs display based on display data onto the screen, the display unit having self-luminous elements arranged, the method comprising the steps of:
upon an update of the display data, receiving a screenful of update display data;
controlling the self-luminous elements to emit light;
after a lapse of a predetermined time period from a driving stop time, reading the update display data stored in a memory and then using the update display data to refresh the screen, the driving stop time being a time when the display unit is stopped from driving based on the update display data, the memory storing a screenful of the update display data; and
controlling the self-luminous elements of the display unit to emit light during no update of the update display data performed on the display driver by the display-data generator.

### Claim 12 (depends on 11)

A non-transitory computer-readable medium storing a display driving program for a computer to execute the individual steps included in the method according to claim 11.