Active-matrix organic light emitting diode (amoled) display apparatus and brightness compensation method thereof

Patent metadata

Field	Value
Publication number	US-2017193909-A1
Application number	US-201615307611-A
Country	US
Kind code	A1
Filing date	Jan 13, 2016
Priority date	Aug 26, 2015
Publication date	Jul 6, 2017
Grant date	—

Abstract

An Active-Matrix Organic Light Emitting Diode (AMOLED) display apparatus and a brightness compensation method thereof are provided. At an initial compensation stage, a display screen can be subjected to brightness calibration by an image sensor so as to acquire a data voltage compensation value of each sub-pixel when a brightness value of a display panel equals a preset value, a first data voltage is output to a corresponding pixel circuit according to the data voltage compensation value of each sub-pixel, a sensed voltage of each sub-pixel at this stage is used as an initial reference voltage of each sub-pixel when the brightness value of the display panel equals the preset value; and at a subsequent compensation stage, by regulating a data voltage of each sub-pixel, the sensed voltage of each sub-pixel is made to be equal to the corresponding initial reference voltage when the brightness value of the display panel equals the preset value, so as to achieve uniform compensation on brightness of each sub-pixel at the subsequent compensation stage. Thus, not only are uniformity and accuracy of initial brightness compensation improved, but also pixel aging is accurately compensated and uniformity and accuracy of subsequent compensation are improved.

First claim

1 . An Active-Matrix Organic Light Emitting Diode (AMOLED) display apparatus, comprising a display panel, wherein the display panel comprises a plurality of sub-pixels, each sub-pixel comprises an Organic Light Emitting Diode (OLED) and a pixel circuit for independently driving the OLED, and the AMOLED display apparatus further comprises:
a drive chip, configured to output a corresponding data voltage to each sub-pixel and acquire a sensed voltage corresponding to each sub-pixel; and a Timing Controller (TCON), configured to: at an initial compensation stage, acquire a corresponding data voltage compensation value when brightness of all the sub-pixels is uniform and consistent under a condition that a brightness value of the display panel is a preset value, by regulating an initial data voltage output to each sub-pixel by the drive chip, control the drive chip to output a first data voltage to the pixel circuit of each sub-pixel according to the data voltage compensation value corresponding to each sub-pixel, acquire the sensed voltage corresponding to each sub-pixel at this stage by the drive chip, and set each sensed voltage as an initial reference voltage corresponding to each sub-pixel under the condition that the brightness value of the display panel equals the preset value; and at a subsequent compensation stage, by changing the data voltage output to each sub-pixel by the drive chip, make the sensed voltage corresponding to each sub-pixel to be equal to the initial reference voltage corresponding to each sub-pixel under the condition that the brightness value of the display panel equals the preset value, so as to achieve uniform compensation on brightness of each sub-pixel at the subsequent compensation stage; and wherein the brightness of each sub-pixel is measured by an image sensor.

2 . The AMOLED display apparatus according to claim 1 , wherein
the brightness includes a gray scale or display brightness.

3 . The AMOLED display apparatus according to claim 1 , wherein
for any one sub-pixel, the data voltage compensation value corresponding to the any one sub-pixel includes:
a first data voltage of the any one sub-pixel when the brightness of all the sub-pixels is uniform and consistent, or
a difference value or a proportional value of the first data voltage and the initial data voltage output to the any one sub-pixel by the drive chip.

4 . The AMOLED display apparatus according to claim 1 , wherein the drive chip includes a Digital-to-Analog Converter (DAC) module and an Analog-to-Digital Converter (ADC) module;
the DAC module is configured to output the data voltage corresponding to each sub-pixel; and the ADC module is configured to detect the sensed voltage corresponding to each sub-pixel.

5 . The AMOLED display apparatus according to claim 1 , wherein
for any one sub-pixel, the sensed voltage corresponding to the any one sub-pixel equals a voltage for a drive thin film transistor (TFT) in the pixel circuit of the any one sub-pixel to charge a line capacitor.

6 . The AMOLED display apparatus according to claim 1 , wherein
the TCON is further configured to: at any one moment, when the brightness value of the display panel is not equal to the preset value, for any one sub-pixel, carry out an interpolation operation by utilizing at least two groups of standard reference data related to the any one moment, calculate the data voltage which needs to be output to the pixel circuit of the any one sub-pixel at the any one moment, and control the drive chip to drive the pixel circuit of the any one sub-pixel according to the calculated data voltage, wherein each group of standard reference data related to the any one moment includes:
a corresponding preset value, and
the data voltage for making the sensed voltage corresponding to the any one sub-pixel to be equal to the initial reference voltage related to both the corresponding preset value and the any one sub-pixel at the any one moment when the brightness value of the display panel equals the corresponding preset value.

7 . A brightness compensation method of an Active-Matrix Organic Light Emitting Diode (AMOLED) display apparatus, comprising:
at an initial compensation stage, by a TCON, acquiring a data voltage compensation value corresponding to each sub-pixel when a brightness of all the sub-pixels is uniform and consistent under a condition that a brightness value of a display panel is a preset value, by regulating an initial data voltage output to each sub pixel by a drive chip, controlling the drive chip to output a first data voltage to a pixel circuit corresponding to each sub-pixel according to the data voltage compensation value corresponding to each sub-pixel, acquiring a sensed voltage corresponding to each sub-pixel at this stage by the drive chip, and setting each sensed voltage as an initial reference voltage corresponding to each sub-pixel under a condition that the brightness value of the display panel equals the preset value; and at a subsequent compensation stage, by the TCON, by changing the data voltage output to each sub-pixel by the drive chip, making the sensed voltage corresponding to each sub-pixel to be equal to the initial reference voltage corresponding to each sub-pixel under the condition that the brightness value of the display panel equals the preset value, so as to achieve uniform compensation on brightness of each sub-pixel at the subsequent compensation stage; wherein the brightness of each sub-pixel is measured by an image sensor.

8 . The method according to claim 7 , wherein
the brightness includes a gray scale or display brightness.

9 . The method according to claim 7 , wherein
for any one sub-pixel, the data voltage compensation value corresponding to the any one sub-pixel includes:
a first data voltage of the any one sub-pixel when the brightness of all the sub-pixels is uniform and consistent; or
a difference value or a proportional value of the first data voltage and the initial data voltage output to the any one sub-pixel by the drive chip.

10 . The method according to claim 7 , wherein
for any one sub-pixel, the sensed voltage corresponding to the any one sub-pixel equals a voltage for a drive thin film transistor (TFT) in the pixel circuit of the any one sub-pixel to charge a line capacitor.

11 . The method according to claim 7 , further comprising:
at any one moment, when the brightness value of the display panel is not equal to the preset value, for any one sub-pixel, carrying out an interpolation operation by utilizing at least two groups of standard reference data related to the any one moment, calculating the data voltage which needs to be output to the pixel circuit of the any one sub-pixel at the any one moment, and controlling the drive chip to drive the pixel circuit of the any one sub-pixel according to the calculated data voltage, wherein each group of standard reference data related to the any one moment includes: a corresponding preset value, and the data voltage for making the sensed voltage corresponding to the any one sub-pixel to be equal to the initial reference voltage related to both the corresponding preset value and the any one sub-pixel at the any one moment when the brightness value of the display panel equals the corresponding preset value.

12 . The AMOLED display apparatus according to claim 2 , wherein
for any one sub-pixel, the data voltage compensation value corresponding to the any one sub-pixel includes:
a first data voltage of the any one sub-pixel when the brightness of all the sub-pixels is uniform and consistent, or
a difference value or a proportional value of the first data voltage and the initial

Assignees

• Boe Technology Group Co Ltd

Inventors

• Song Danna
• Wu Zhongyuan
• Tseng Szu Heng
• Meng Song

Classifications

• G09G3/3233 Primary

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

• G09G2310/08

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

• G09G2320/0295

  by monitoring each display pixel · CPC title

• G09G2310/027

  Details of drivers for data electrodes, the drivers handling digital grey scale data, e.g. use of D/A converters · CPC title

• G09G2320/0233

  Improving the luminance or brightness uniformity across the screen · CPC title