Organic light-emitting diode display and method of driving the same

Patent metadata

Field	Value
Publication number	US-2016019838-A1
Application number	US-201414562431-A
Country	US
Kind code	A1
Filing date	Dec 5, 2014
Priority date	Jul 17, 2014
Publication date	Jan 21, 2016
Grant date	—

Abstract

An organic light-emitting diode (OLED) display and a method of driving the display are disclosed. In one aspect, the method includes receiving input image data, calculating a load value corresponding to a driving amount of the input image data, and calculating a luminance adjustment value for each of the pixels based at least in part on the load value and a voltage drop proportional value of each of the pixels. The voltage drop proportional value corresponds to a ratio of a voltage drop value to a maximum voltage drop value. The method also includes generating output image data based at least in part on the input image data and the luminance adjustment value and displaying an image corresponding to the output image data.

First claim

What is claimed is:

1 . A method of driving an organic light-emitting diode (OLED) display comprising a plurality of pixels, the method comprising:
receiving input image data; calculating a load value corresponding to a driving amount of the input image data; calculating a luminance adjustment value for each of the pixels based at least in part on the load value and a voltage drop proportional value of each of the pixels, wherein the voltage drop proportional value corresponds to a ratio of a voltage drop value to a maximum voltage drop value; generating output image data based at least in part on the input image data and the luminance adjustment value; and displaying an image corresponding to the output image data.

2 . The method of claim 1 , wherein the load value is calculated according to Equation 1 below:
Load= K r *ΣR i +K g *ΣG i +K b *ΣB i , wherein Load corresponds to the load value, Ri, Gi and Bi respectively correspond to red, green and blue color image data included in the input image data, and Kr, Kg and Kb respectively correspond to gains of the red, green and blue color image data.

3 . The method of claim 2 , wherein the load value is calculated every predetermined frame period.

4 . The method of claim 1 , wherein the voltage drop proportional value is greater than about 0 and less than or substantially equal to about 1.

5 . The method of claim 1 , wherein the voltage drop proportional value is determined based at least in part on distances between the pixels and a driver that drives the OLED display.

6 . The method of claim 1 , wherein the luminance adjustment value is determined by multiplying the voltage drop proportional value by a ratio of the load value to a maximum load value.

7 . The method of claim 1 , wherein the output image data is determined by multiplying the input image data by the luminance adjustment value.

8 . The method of claim 1 , further comprising:
calculating a grayscale distribution value of the input image data; generating conversion information for stretching the input image data based at least in part on the grayscale distribution value; and modulating the input image data based at least in part on the conversion information.

9 . The method of claim 8 , wherein an input grayscale value of the input image data is transformed into an output grayscale based at least in part on the conversion information, and
wherein a ratio of a change amount of the output grayscale value to a change amount of the input grayscale value is proportional to the grayscale distribution value.

10 . An organic light-emitting diode (OLED) display comprising:
a display panel including a plurality of pixels; a scan driver configured to provide a plurality of scan signals to the pixels; a data driver configured to provide a plurality of data signals to the pixels; a data adjuster configured to i) calculate a load value corresponding to a driving amount of input image data and ii) adjust the input image data based at least in part on the load value and a voltage drop proportional value of each of the pixels so as to generate output image data, wherein the voltage drop proportional value corresponds to a ratio of a voltage drop value to a maximum voltage drop value; and a timing controller configured to control the scan driver and the data driver so as to display an image corresponding to the output image data.

11 . The display of claim 10 , wherein the data adjuster includes:
a load value calculator configured to calculate the load value based at least in part on the input image data; a luminance adjustment value calculator configured to calculate a luminance adjustment value for each of the pixels based at least in part on the load value and the voltage drop proportional value; and an output image data generator configured to generate the output image data based at least in part on the input image data and the luminance adjustment value.

12 . The display of claim 11 , wherein the load value calculator is further configured to calculate the load value according to Equation 1 below:
Load= K r *ΣR i +K g *ΣG i +K b *ΣB i , wherein Load corresponds to the load value, Ri, Gi and Bi respectively correspond to red, green and blue color image data included in the input image data, and Kr, Kg and Kb respectively correspond to gains of the red, green and blue color image data.

13 . The display of claim 12 , wherein the load value calculator is further configured to calculate the load value every predetermined frame period.

14 . The display of claim 11 , wherein the voltage drop proportional value is greater than about 0 and less than or substantially equal to about 1.

15 . The display of claim 11 , wherein the voltage drop proportional value is configured to be determined based at least in part on distances between the pixels and the data driver.

16 . The display of claim 11 , wherein the luminance adjustment value calculator is further configured to multiply the voltage drop proportional value by a ratio of the load value to a maximum load value so as to determine the luminance adjustment value.

17 . The display of claim 11 , wherein the output image data generator is further configured to multiply the input image data by the luminance adjustment value so as to determine the output image data.

18 . The display of claim 11 , wherein the data adjuster further includes:
a grayscale distribution analyzer configured to calculate a grayscale distribution value of the input image data; a conversion information generator configured to generate conversion information configured to stretch the input image data based at least in part on the grayscale distribution value; and an image data modulator configured to modulate the input image data based at least in part on the conversion information.

19 . The display of claim 18 , wherein the grayscale distribution analyzer is further configured to convert a format of the input image data to YCbCr-format so as to calculate the grayscale distribution value.

20 . The display of claim 18 , wherein the image data modulator is further configured to transform an input grayscale value of the input image data into an output grayscale based at least in part on the conversion information, and
wherein a ratio of a change amount of the output grayscale value to a change amount of the input grayscale value is proportional to the grayscale distribution value.

Assignees

• Samsung Display Co Ltd

Inventors

• Park Jong-Woong

Classifications

• G09G3/3258 Primary

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

• G09G3/2003

  Display of colours (specific for liquid crystal displays G09G3/3607) · CPC title

• G09G2310/08

  Details of timing specific for flat panels, other than clock recovery · CPC title

• G09G3/3208 Primary

  organic, e.g. using organic light-emitting diodes [OLED] · CPC title

• G09G2360/16

  Calculation or use of calculated indices related to luminance levels in display data · CPC title