Organic light emitting display device

Patent metadata

Field	Value
Publication number	US-9355596-B2
Application number	US-201314022117-A
Country	US
Kind code	B2
Filing date	Sep 9, 2013
Priority date	Apr 30, 2013
Publication date	May 31, 2016
Grant date	May 31, 2016

Abstract

An organic light emitting diode display including a display including data lines, scan lines, sense lines, and pixels electrically coupled to the data, scan, and sense lines, a compensator for sensing first and second driving currents flowing to the pixels corresponding to first and second test data in a compensation mode, to compare first and second reference currents with the first and second driving currents, respectively, and to update compensation data, a signal controller for compensating input data according to the compensation data to generate image data, and for changing the input data into the first and second test data in the compensation mode; and a data driver for generating a plurality of data signals by using one of the image data, the first and second test data, and to supply the data signals to the data lines.

First claim

What is claimed is:

1. An organic light emitting diode display comprising:
a display comprising a plurality of data lines, a plurality of scan lines, a plurality of sense lines, and a plurality of pixels electrically coupled to the data lines, the scan lines, and the sense lines;
a compensator configured to sense first driving currents and second driving currents flowing to the pixels corresponding to first test data and second test data, respectively, in a compensation mode, to compare first reference currents and second reference currents with the first driving currents and the second driving currents, respectively, and to update compensation data corresponding to a variation of a mobility characteristic variable and a variation of a threshold voltage characteristic variable by selectively increasing or decreasing at least one of the variation of the mobility characteristic variable and the variation of the threshold voltage characteristic variable based on a result of the comparison;
a signal controller configured to compensate input data according to the compensation data to generate image data, and to change the input data into the first test data and the second test data in the compensation mode; and
a data driver configured to generate a plurality of data signals by using one of the image data, the first test data, and the second test data, and to supply the data signals to the data lines.

2. The organic light emitting diode display of claim 1 , wherein the compensator comprises:
a current sensor configured to sense the first driving currents and the second driving currents through the sense lines in the compensation mode;
a comparator configured to compare the first driving currents with the first reference currents to output first comparison data, and to compare the second driving currents with the second reference currents to output second comparison data;
a compensation data processor configured to update the compensation data according to the first comparison data and the second comparison data; and
a memory configured to store value of the first reference currents, value of the second reference currents, and the compensation data.

3. The organic light emitting diode display of claim 2 , wherein each of the pixels comprises:
an organic light emitting diode; and
a driving transistor configured to drive the organic light emitting diode according to one of the data signals.

4. An organic light emitting diode display comprising:
a display comprising a plurality of data lines, a plurality of scan lines, a plurality of sense lines, and a plurality of pixels electrically coupled to the data lines, the scan lines, and the sense lines;
a compensator configured to sense first driving currents and second driving currents flowing to the pixels corresponding to first test data and second test data, respectively, in a compensation mode, to compare first reference currents and second reference currents with the first driving currents and the second driving currents, respectively, and to update compensation data;
a signal controller configured to compensate input data according to the compensation data to generate image data, and to change the input data into the first test data and the second test data in the compensation mode; and
a data driver configured to generate a plurality of data signals by using one of the image data, the first test data, and the second test data, and to supply the data signals to the data lines,
wherein each of the pixels comprises:
an organic light emitting diode; and
a driving transistor configured to drive the organic light emitting diode according to one of the data signals,

wherein the compensator comprises:
a current sensor configured to sense the first driving currents and the second driving currents through the sense lines in the compensation mode;
a comparator configured to compare the first driving currents with the first reference currents to output first comparison data, and to compare the second driving currents with the second reference currents to output second comparison data;
a compensation data processor configured to update the compensation data according to the first comparison data and the second comparison data; and
a memory configured to store value of the first reference currents, value of the second reference currents, and the compensation data, and

wherein characteristic data of the driving transistor comprising a mobility characteristic variable, a variation of the mobility characteristic variable, a threshold voltage characteristic variable, and a variation of the threshold voltage characteristic variable, are related according to
Id =( k +α)×{ V data−( Vt −β)) p }

where the Id is a current flowing to the driving transistor, the Vdata is a voltage corresponding to the data signal, k is the mobility characteristic variable, Vt is the threshold voltage characteristic variable, α is the variation of the mobility characteristic variable, β is the variation of the threshold voltage characteristic variable, and P is a constant with a value of 1 to 2.

5. The organic light emitting diode display of claim 4 , wherein the compensation data processor is further configured to store value of the first driving currents and value of the second driving currents flowing to the pixels in the memory as value of the first reference currents and value of the second reference currents, according to the first test data and the second test data at an initial operation.

6. The organic light emitting diode display of claim 4 , wherein the compensation data processor is further configured to set the variation of the mobility characteristic, variable and the variation of the threshold voltage characteristic variable as 0 at an initial operation.

7. The organic light emitting diode display of claim 4 , wherein the compensation data processor is further configured to change the variation of at least one of the mobility characteristic variable or the threshold voltage characteristic variable by ±1 according to the first comparison data and the second comparison data.

8. The organic light emitting diode display of claim 7 , wherein the compensation data processor is further configured to change the variation of the threshold voltage characteristic variable by +1 when a corresponding one of the first driving currents is less than a corresponding one of the first reference currents and a corresponding one of the second driving currents is less than a corresponding one of the second reference currents.

9. The organic light emitting diode display of claim 7 , wherein the compensation data processor is further configured to change the variation of the threshold voltage characteristic variable by −1 when a corresponding one of the first driving currents is greater than a corresponding one of the first reference currents and a corresponding one of the second driving currents is greater than a corresponding one of the second reference currents.

10. The organic light emitting diode display of claim 7 , wherein the compensation data processor is further configured to change the variation of the mobility characteristic variable and the variation of the threshold voltage characteristic variable by −1 when a corresponding one of the first driving currents is less than a corresponding one of the first reference currents and a corresponding one of the second driving currents is greater than a corresponding one of the second reference currents.

11. The organic light emitting diode display of claim 7 , wherein the compensation data processor is further configured to change the variation of the mobility characteristic variable and the variation of the threshold volta

Assignees

• Samsung Display Co Ltd

Inventors

• Shin Choong-Sun
• Song In-Bok
• Kim Jeong-Kyoo
• Won Young-Uk

Classifications

• G09G2300/0819

  used for counteracting undesired variations, e.g. feedback or autozeroing · CPC title

• G09G3/3233

  with pixel circuitry controlling the current through the light-emitting element · CPC title

• G09G2320/0295

  by monitoring each display pixel · CPC title

• G09G2320/0271

  Adjustment of the gradation levels within the range of the gradation scale, e.g. by redistribution or clipping · CPC title

• G09G3/3275 Primary

  Details of drivers for data electrodes · CPC title