Display device and method of driving display device

Patent metadata

Field	Value
Publication number	US-2016293101-A1
Application number	US-201514861089-A
Country	US
Kind code	A1
Filing date	Sep 22, 2015
Priority date	Apr 6, 2015
Publication date	Oct 6, 2016
Grant date	—

Abstract

A method of driving a display device includes calculating an average load and an asymmetry by analyzing an input image data, and adjusting at least one of a high data voltage and a low data voltage, which are supplied to a display panel of the display device, based on the average load and the asymmetry.

First claim

What is claimed is:

1 . A method of driving a display device, the method comprising:
generating a plurality of sub-image data by dividing an input image data supplied to a display panel of the display device into the plurality of sub-image data corresponding to a plurality of blocks of the display panel, respectively; calculating sub-loads for the plurality of blocks based on the plurality of sub-image data, respectively; and adjusting at least one of a high data voltage and a low data voltage, which are supplied to the display panel, by analyzing the sub-loads.

2 . The method of claim 1 , wherein
the high data voltage is a data voltage for turning off a driving transistor included in a pixel of the display panel, and the low data voltage is a data voltage for turning on the driving transistor.

3 . The method of claim 1 , wherein the calculating the sub-loads comprises:
calculating average grayscales for the plurality of blocks based on the plurality of sub-image data, respectively; and calculating the sub-loads based on the average grayscales, respectively.

4 . The method of claim 1 , wherein the adjusting the at least one of the high data voltage and the low data voltage comprises:
calculating an asymmetry of the input image data based on the sub-loads; and generating a voltage control signal, which changes at least one of the high data voltage and the low data voltage, based on the sub-loads and the asymmetry.

5 . The method of claim 4 , wherein the generating the voltage control signal comprises:
generating the voltage control signal based on at least one of a selected sub-load and the asymmetry when the asymmetry is within a specified range, wherein the selected sub-load is selected among the sub-loads; and generating the voltage control signal based on an average load of the sub-loads when the asymmetry is out of the specified range.

6 . The method of claim 4 , wherein the generating the voltage control signal comprises:
selecting a minimum sub-load of the sub-loads; and generating the voltage control signal based on the minimum sub-load, wherein the voltage control signal adjusts the high data voltage.

7 . The method of claim 4 , wherein the generating the voltage control signal comprises:
selecting a maximum sub-load of the sub-loads; and generating the voltage control signal based on the maximum sub-load, wherein the voltage control signal adjusts the low data voltage.

8 . The method of claim 4 , wherein the generating the voltage control signal comprises:
determining a supply voltage level of a first power voltage which is supplied to the display panel; calculating a first current-resistance drop of the first power voltage by analyzing the sub-loads; calculating a first local voltage level of the first power voltage by subtracting the first current-resistance drop from the supply voltage level; calculating a first target voltage level by subtracting a first offset voltage from the first local voltage level; and generating the voltage control signal based on the first target voltage level, wherein the voltage control signal adjusts the high data voltage.

9 . The method of claim 8 , wherein the first current-resistance drop of the first power voltage is calculated based on a minimum sub-load of the sub-loads.

10 . The method of claim 8 , wherein
a driving transistor included in a pixel of the display panel is turned off in response to the high data voltage, and the first offset voltage has a substantially constant level determined based on a gate-source voltage of the turned-off driving transistor.

11 . The method of claim 4 , wherein the adjusting the at least one of the high data voltage and the low data voltage comprises:
determining a supply voltage level of a first power voltage which is supplied to the display panel; calculating a second current-resistance drop of the first power voltage by analyzing the sub-loads; calculating a second local voltage level of the first power voltage by subtracting the second current-resistance drop from the supply voltage level; calculating a second target voltage level by subtracting a second offset voltage from the second local voltage level; and generating the voltage control signal based on the second target voltage level, wherein the voltage control signal adjusts the low data voltage.

12 . The method of claim 11 , wherein the second current-resistance drop of the first power voltage is calculated based on a maximum sub-load of the sub-loads.

13 . The method of claim 11 , wherein
a driving transistor included in a pixel of the display panel is turned on in response to the low data voltage, and the second offset voltage has a substantially constant level determined based on a gate-source voltage of the turned-on driving transistor.

14 . A method of driving a display device, the method comprising:
calculating an average load and an asymmetry by analyzing an input image data; and adjusting at least one of a high data voltage and a low data voltage, which are supplied to a display panel of the display device, based on the average load and the asymmetry.

15 . The method of claim 14 , wherein the calculating the average load and the asymmetry comprises:
generating a plurality of sub-image data by dividing the input image data into the plurality of sub-input image data corresponding to a plurality of blocks of the display panel, respectively; calculating sub-loads of the plurality of blocks based on the plurality of sub-input image data, respectively; calculating the average load based on the sub-loads; and calculating the asymmetry based on the sub-loads and the average load.

16 . The method of claim 15 , wherein the adjusting the at least one of the high data voltage and the low data voltage comprises:
generating a voltage control signal, which adjusts at least one of the high data voltage and the low data voltage, based on the average load; and compensating the voltage control signal based on the asymmetry.

17 . The method of claim 16 , wherein the compensating the voltage control signal comprises:
determining whether the asymmetry is within a specified range; selecting a minimum sub-load among the sub-loads when the asymmetry is within the specified range; and compensating the voltage control signal based on the minimum sub-load, wherein the voltage control signal adjusts the high data voltage.

18 . The method of claim 16 , wherein the compensating the voltage control signal comprises:
determining whether the asymmetry is within a specified range; selecting a maximum sub-load among the sub-loads when the asymmetry is within the specified range; and compensating the voltage control signal based on the maximum sub-load, wherein the voltage control signal adjusts the low data voltage.

19 . A display device comprising:
a display panel; a sub-load calculator which generates a plurality of sub-image data by dividing an input image data into a plurality of blocks and calculates sub-loads for the plurality of blocks based on the plurality of sub-input image data, respectively; a data voltage controller which calculates an asymmetry of the input image data based on the sub-loads and generates a voltage control signal based on the sub-loads and the asymmetry; and a power supplier which adjusts at least one of a high data voltage and a low data voltage based on the voltage control signal, wherein the high data voltage and the low data voltage are supplied to the display panel.

Assignees

• Samsung Display Co Ltd

Inventors

• Jeong Il-Hun
• Lee Jae-Hoon

Classifications

• G09G3/3258 Primary

  with pixel circuitry controlling the voltage across the light-emitting element · CPC title

• G09G2330/027

  Arrangements or methods related to powering off a display · CPC title

• G09G3/2007 Primary

  Display of intermediate tones · CPC title

• G09G3/3225 Primary

  using an active matrix · CPC title

• G09G2330/021

  Power management, e.g. power saving · CPC title