Regulating method and regulating apparatus for a driving voltage of a display module

Patent metadata

Field	Value
Publication number	US-10453378-B2
Application number	US-201615099090-A
Country	US
Kind code	B2
Filing date	Apr 14, 2016
Priority date	Jun 11, 2015
Publication date	Oct 22, 2019
Grant date	Oct 22, 2019

Abstract

A regulating method and a regulating apparatus for a driving voltage of a display module, wherein the method comprises: applying, to the display module, a gamma voltage pair corresponding to a grayscale to be tested, selecting a test image and maintaining the test image for a predetermined time duration ( 11 ); switching to a predetermined grayscale image that matches the grayscale to be tested, regulating a common voltage of the display module, and recording a direction and a magnitude of regulation of the common voltage ( 12 ); and restoring the common voltage to a magnitude before the regulation, and regulating the first gamma voltage and the second gamma voltage according to the recorded direction and magnitude of regulation of the common voltage ( 13 ). Regulation accuracy of the driving voltage can be improved, workload for debugging can be reduced and work efficiency can be improved.

First claim

What is claimed is:

1. A regulating method for a driving voltage of a display module, comprising:
applying, to the display module, a gamma voltage pair corresponding to a grayscale to be tested, selecting a test image and maintaining the test image for a predetermined time duration, the gamma voltage pair including a first gamma voltage and a second gamma voltage;
switching to a predetermined grayscale image that matches the grayscale to be tested, regulating a common voltage of the display module so that a retention level of a residual image generated by the test image meets set requirements, and recording a direction and a magnitude of regulation of the common voltage; and
restoring the common voltage to a magnitude before the regulation, determining a voltage offset required for the first gamma voltage and a voltage offset required for the second gamma voltage according to the direction and the magnitude of regulation of the common voltage, regulating the first gamma voltage and the second gamma voltage in the same direction and with the same amplitude according to the direction of regulation of the common voltage and the required voltage offsets, to obtain a first gamma voltage to be tested and a second gamma voltage to be tested, applying, to the display module, the first gamma voltage to be tested and the second gamma voltage to be tested, so that a retention level of a residual image of the display module as being driven by the first gamma voltage to be tested and the second gamma voltage to be tested meets the set requirements.

2. The regulating method according to claim 1 , further comprising:
prior to regulating the common voltage of the display component, measuring a first luminance at a different location, and determining a type of a residual image generated by the test image and a retention level of the residual image according to the first luminance.

3. The regulating method according to claim 1 , further comprising:
regulating the common voltage of the display module, to weaken the retention level of the residual image;
measuring a second luminance at a different location, and determining the retention level of the residual image according to the second luminance;
determining whether the retention level of the residual image meets the set requirements; and
recording a direction and a magnitude of regulation of the common voltage if the retention level of the residual image meets the set requirements; otherwise, continuing to regulate the common voltage.

4. The regulating method according to claim 1 , further comprising:
again switching to the test image and maintaining the test image for the predetermined time duration;
switching to a predetermined grayscale image that matches the grayscale to be tested, measuring a third luminance at a different location, and determining a type of the residual image generated by the test image and a retention level of the residual image according to the third luminance;
determining whether the retention level of the residual image meets the set requirements; and
when the retention level of the residual image meets the set requirements, determining the first gamma voltage to be tested and the second gamma voltage to be tested as a regulated first gamma voltage and a regulated second gamma voltage of the display module.

5. The regulating method according to claim 4 , further comprising:
when the retention level of the residual image does not meet the set requirements, determining whether the type of the residual image is consistent with that of an initial residual image, according to the type of the residual image generated when applying, to the display module, the first gamma voltage to be tested and the second gamma voltage to be tested;
if consistent, continuing to regulate the common voltage in the same direction so that the retention level of the residual image meets the set requirements; if not consistent, regulating the common voltage in an inverse direction so that the retention level of the residual image meets the set requirements.

6. The regulating method according to claim 1 , wherein when the display module is in a normally black display mode, the grayscale to be tested is set as L255, and the predetermined grayscale image that matches the grayscale to be tested is set as a middle-to-low grayscale image; when the display component is in a normally white display mode, the grayscale to be tested is set as L0, and the predetermined grayscale image that matches the grayscale to be tested is set as a middle-to-high grayscale image.

7. The regulating method according to claim 1 , wherein the test image is a predetermined black-and-white checkerboard image.

8. A regulating apparatus for a driving voltage of a display module, comprising:
a display module configured to display a test image and a predetermined grayscale image that matches a grayscale to be tested;
a regulation module configured to regulate, after switching to the predetermined grayscale image that matches the grayscale to be tested, a common voltage of the display module so that a retention level of a residual image generated by the test image meets set requirements, and to record a direction and a magnitude of regulation of the common voltage, and configured to restore the common voltage to a magnitude before the regulation, and to determine a voltage offset required for the first gamma voltage and a voltage offset required for the seco gamma voltage according to the direction and the magnitude of regulation of the common voltage; regulate the first gamma voltage and the second gamma voltage in the same direction and with the sale amplitude according to the direction of regulation of the common voltage and the required voltage offsets, to obtain a first gamma voltage to be tested and a second gamma voltage to be tested, and configured to apply to the display module, the first gamma voltage to be tested and the second gamma voltage to be tested, so that a retention level of a residual image of the display module as being driven by the first gamma voltage to be tested and the second gamma voltage to be tested meets the set requirements; and
a driving module configured to apply, to the display module, a gamma voltage pair corresponding to the grayscale to be tested so that the display module displays the test image and maintains the test image for a predetermined time duration, the gamma voltage pair including a first gamma voltage and a second gamma voltage.

9. The regulating apparatus according to claim 8 , further comprising:
a luminance measuring module configured to measure a first luminance at a different location prior to regulating the common voltage of the display component, to measure a second luminance at a different location after regulating the common voltage, and to measure a third luminance at a different location after regulating the first gamma voltage and the second gamma voltage;
a data processing module configured to determine a type and a retention level of the residual image prior to regulating the common voltage according to the first luminance, to determine a type and a retention level of the residual image after regulating the common voltage according to the second luminance, and to determine a type and a retention level of the residual image generated as being driven by the regulated first gamma voltage and the regulated second gamma voltage according to the third luminance; and
a determining module configured to determine whether the retention level of the residual image after regulating the common voltage meets the set requirements, and to determine whether the retention level of the residual image as being driven by the regulated first gamma voltage and the regulated second gamma vol

Assignees

• Boe Technology Group Co Ltd
• Beijing Boe Optoelectronics Tech Co Ltd

Inventors

• Ding Jinbo
• Zhang Ying
• Li Xin
• Li Dawei
• Wang Changjiang
• Yuan Xuchen

Classifications

• G09G2320/0673

  for control of gamma adjustment, e.g. selecting another gamma curve · CPC title

• G09G3/3648 Primary

  using an active matrix (G09G3/367 - G09G3/3696 take precedence) · CPC title

• G09G2320/0686

  with two or more screen areas displaying information with different brightness or colours · CPC title

• G09G3/006

  Electronic inspection or testing of displays and display drivers, e.g. of LED or LCD displays (testing individual LED's G01R31/2635; testing lamps G01R31/44; testing of optical features of LCD displays G02F1/1309) · CPC title

• G09G3/2092 Primary

  Details of a display terminals using a flat panel, the details relating to the control arrangement of the display terminal and to the interfaces thereto (suitable for both CRT and flat panel G09G5/003; specific for a CRT G09G1/165) · CPC title