METHOD OF MORE QUICKLY CALIBRATING DISPLAY PANELS AND CALIBRATION APPARATUS FOR PERFORMING THE SAME

• US 20150194105A1
• Filed: 07/25/2014
• Published: 07/09/2015
• Est. Priority Date: 01/03/2014
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: HAN, Jung-Suk, MOON, Hoi-Sik, KIM, Kang-Hyun, JUNG, Woo-Jin, NA, Jong-Hee, CHUNG, Jae-Seob
• Granted Patent: US 9,754,545 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G02F 1/1309 Repairing; Testing
• CPC Class Codes: G09G 2320/0233 Improving the luminance or brightness uniformity across the screen
• CPC Class Codes: G09G 2320/0276 for the purpose of adaptation to the characteristics of a display device, i.e. gamma correction
• CPC Class Codes: G09G 2320/0666 for control of colour parameters, e.g. colour temperature
• CPC Class Codes: G09G 2320/068 for control of viewing angle adjustment
• CPC Class Codes: G09G 2320/0693 Calibration of display systems
• CPC Class Codes: G09G 3/2003 Display of colours specific for liquid crystal displays G09G3/3607
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence

Abstract

A method of reducing a total, per device, measurements taking time in a calibration system that uses a sensor array that serially reports out its readings and a data processing unit that needs to receive the reported out readings in good order before allowing an under-measurement first display device to advance away from a measurements taking station includes the step of not driving the first display device with all of required full screen test images where each is a full screen display of only a respective one of a predetermined minimum number of grayscale values produced as a minimum number of needed full screen sample images and; in place of at least a first plurality of the not-produced full screen images, driving the under-measurement first display device with a partial screen multi-pattern that presents a plurality of different grayscale values including ones not presented by those of all of the full screen test images that are used to drive the under-measurement first display device. The serially reported out readings from the sensor array for the partial screen multi-pattern and for the full screen test images are obtained and used to generate virtual full screen sample images based on the obtained partial screen multi-pattern and for the full screen test images.

Claims

1. A machine implemented method of compensating an image of a display panel, the method comprising:

measuring luminance and color of a plurality of full pattern images, the full pattern image including a single full grayscale;

measuring luminance and color of a multi pattern image, the multi pattern image including a plurality of multi grayscales;

generating a first compensating value to displace a position of a multi grayscale region in the multi pattern image to a central portion of the multi pattern image; and

compensating luminance and color of the display panel based on the luminance and the color of the full pattern image, the luminance and the color of the multi pattern image and the first compensating value.

2. The method of claim 1, wherein the first compensating value is generated based on measurements taken from a high full image and a low full image, the high full image having a high full grayscale which is one of the full grayscales greater than the multi grayscale and adjacent to the multi grayscale, the low full image having a low full grayscale which is one of the full grayscales less than the multi grayscale and adjacent to the multi grayscale.

3. The method of claim 2, wherein the generating of the first compensating value comprises:

determining a first difference between a measured value of the high full grayscale at a first position and a measured value of the high full grayscale at a second position in the high full image and a second difference between a measured value of the low full grayscale at the first position and a measured value of the low full grayscale at the second position in the low full image, the first position being a central portion of the multi pattern image, the second position being the position of the multi grayscale region; and

linearly interpolating the first difference and the second difference using the high full grayscale, the multi grayscale and the low full grayscale.

4. The method of claim 1, wherein the multi pattern image includes a common multi grayscale which is substantially the same as one of the full grayscales.

5. The method of claim 4, further comprising generating a second compensating value using a ratio between a measured value of the full grayscale which is substantially the same as the common multi grayscale and a measured value of the common multi grayscale in the multi pattern image.

6. The method of claim 5, wherein a measured position of the measured value of the full grayscale which is substantially the same as the common multi grayscale is substantially the same as a measured position of the measured value of the common multi grayscale in the multi pattern image.

7. The method of claim 1, wherein the number of the full pattern images is greater than or equal to three.

8. The method of claim 1, wherein the number of the multi pattern images is two, and

a first multi pattern image among the multi pattern images corresponds to relatively low grayscales and a second multi pattern image among the multi pattern images corresponds to relatively high grayscales.

9. A method of driving a display panel, the method comprising:

measuring luminance and color of a plurality of full pattern images, the full pattern image including a single full grayscale;

measuring luminance and color of a multi pattern image, the multi pattern image including a plurality of multi grayscales;

generating a first compensating value to displace a position of a multi grayscale region in the multi pattern image to a central portion of the multi pattern image;

compensating luminance and color of input image data based on the input image data, the luminance and the color of the full pattern image, the luminance and the color of the multi pattern image and the first compensating value to generate a data signal; and

displaying an image on the display panel based on the data signal.

10. The method of claim 9, wherein the first compensating value is generated using a high full image and a low full image, the high full image having a high full grayscale which is one of the full grayscales greater than the multi grayscale and adjacent to the multi grayscale, the low full image having a low full grayscale which is one of the full grayscales less than the multi grayscale and adjacent to the multi grayscale.

11. The method of claim 9, wherein the multi pattern image includes a common multi grayscale which is substantially the same as one of the full grayscales.

12. The method of claim 11, further comprising generating a second compensating value using a ratio between a measured value of the full grayscale which is substantially the same as the common multi grayscale and a measured value of the common multi grayscale in the multi pattern image.

13. The method of claim 9, wherein the number of the full pattern images is greater than or equal to three.

14. A display apparatus comprising:

a timing controller configured to compensate luminance and color of input image data to generate a data signal based on the input image data, luminance and color of a plurality of full pattern images, luminance and color of a multi pattern image and a first compensating value to displace a position of a multi grayscale region in the multi pattern image to a central portion of the multi pattern image, the full pattern image including a single full grayscale, the multi pattern image including a plurality of multi grayscales;

a data driver configured to convert the data signal into a data voltage having an analog type; and

a display panel configured to display an image based on the data voltage.

15. The display apparatus of claim 14, wherein the first compensating value is generated using a high full image and a low full image, the high full image having a high full grayscale which is one of the full grayscales greater than the multi grayscale and adjacent to the multi grayscale, the low full image having a low full grayscale which is one of the full grayscales less than the multi grayscale and adjacent to the multi grayscale.

16. The display apparatus of claim 14, wherein the multi pattern image includes a common multi grayscale which is substantially the same as one of the full grayscales.

17. The display apparatus of claim 16, wherein the timing controller is further configured to generate a second compensating value using a ratio between a measured value of the full grayscale which is substantially the same as the common multi grayscale and a measured value of the common multi grayscale in the multi pattern image.

18. The display apparatus of claim 14, wherein the number of the full pattern images is greater than or equal to three.

19. A method of reducing a total, per device, measurements taking time in a calibration system that uses a sensor array that serially reports out its readings and a data processing unit that needs to receive the reported out readings in good order before allowing an under-measurement first display device to be moved away from a measurements taking position, the method comprising:

not driving the under-measurement first display device with all full screen test images each being a full screen display of only a respective one of a predetermined minimum number of grayscale values produced as a full screen sample images;

in place of at least a first plurality of the not-produced full screen images, driving the under-measurement first display device with a partial screen multi-pattern that presents a plurality of different grayscale values including ones not presented by those of all of the full screen test images that are used to drive the under-measurement first display device; and

obtaining serially reported out readings from the sensor array for the partial screen multi-pattern and for the full screen test images that are used to drive the under-measurement first display device.

20. A machine implemented and automated method for quickly determining luminance and color compensation values for a display panel having a display area populated by a matrix of pixels, where each pixel is independently drivable over a predetermined range of grayscales, the method comprising:

first driving all the pixels with a first single full grayscale signal to thereby produce a corresponding first full screen image and using a sensor array to measure luminance and color attributes of the produced first full screen image;

second driving all the pixels with a different second single full grayscale signal to thereby produce a corresponding second full screen image and using the sensor array to measure luminance and color attributes of the produced second full screen image;

third driving at least a subset of the pixels of the display area with a corresponding multi pattern signal to thereby produce a corresponding multi pattern image having a predetermined spatial arrangement of darker and lighter regions and using the sensor array to measure respective luminances and color attributes of the respective and spatially arranged darker and lighter regions of the multi pattern image;

using the measured luminances and color attributes of the multi pattern image and of the first and second full screen images to generate luminance and color calibrating factors for the display panel.