CN100487783C - Brightness correction method and system applying same - Google Patents

Abstract

A brightness correction method is applicable to a display panel. First, in the display panel, multiple image areas are displayed according to display colors, wherein the display color of any image area is different from the display colors of the remaining image areas. Then, the luminance values corresponding to different grayscale values of the image area are detected, wherein the grayscale values have corresponding gamma voltages. Finally, according to the detected luminance values, the gamma voltage corresponding to the grayscale values is adjusted.

Description

Brightness correction method and system using the brightness correction method

technical field

The present invention relates to a calibration method and system, in particular to a brightness calibration method and system.

Background technique

Due to the advantages of thin volume, light weight and low electromagnetic radiation, Liquid Crystal Display (LCD) has been widely used in recent years. For liquid crystal displays, since the cross-voltage between the lower plate and the lower plate of the liquid crystal panel is not in a linear relationship with the light transmittance, when the digital pixel data to be displayed is converted into a voltage signal input to both sides of the liquid crystal , the action of Gamma voltage correction must be performed to reduce the color distortion of the liquid crystal display.

Generally, the image presented by the liquid crystal display is composed of three primary colors (RGB). Therefore, when performing the Gamma voltage correction operation, it is necessary to perform Gamma voltage correction for the three primary colors, so that it may take time to perform the Gamma voltage correction operation for a single display panel. 10~15 minutes.

Since the Gamma voltage calibration of the display panel takes a lot of time, when the display panels are mass-produced, the Gamma voltage calibration cannot be performed for each display panel. Therefore, most manufacturers of liquid crystal displays obtain a set of standard Gamma voltages during the R&D stage, and then use the set of standard Gamma voltages to directly burn them into each display panel.

However, the characteristics of each display panel are not necessarily the same. Therefore, when each display panel uses this standard Gamma voltage, it will easily cause problems such as different hue, color shift, or color temperature deviation of the displayed color of the display panel.

Contents of the invention

In view of this, the present invention provides a brightness calibration method suitable for a display panel. Firstly, in the display panel, a plurality of image areas are displayed according to display colors, wherein the display color of any image area is different from the display colors of the remaining image areas. Next, the luminance values corresponding to different gray scale values in the image area are detected, wherein the above gray scale values have corresponding Gamma voltages respectively. Finally, according to the detected luminance value, the Gamma voltage corresponding to the gray scale value is adjusted.

In addition, the present invention also provides a brightness calibration system, including a display panel, a brightness detection device, and a processing device. The display panel is used for displaying a plurality of image areas according to display colors, wherein the display color of any image area is different from that of the rest of the image areas. The luminance detection device detects luminance values corresponding to different gray scale values in the image area, wherein the gray scale values have corresponding Gamma voltages respectively. The processing device adjusts the Gamma voltage corresponding to the gray scale value according to the detected luminance value.

Since the present invention measures the luminance of multiple image regions simultaneously, the time for Gamma voltage correction can be greatly reduced to 2 minutes. When the brightness detection device only detects every five gray scale values, the time for Gamma voltage correction can also be shortened. When the time for Gamma voltage calibration is greatly reduced, Gamma voltage calibration can be performed simultaneously while producing the display panel. After the Gamma voltage correction is performed on each display panel, the possibility of different hue, color shift, or color temperature deviation of the display panel can be reduced.

Description of drawings

In order to make the above and other objects, features, and advantages of the present invention clearly understandable, the preferred embodiments are specifically listed below, together with the accompanying drawings, and are described in detail as follows:

FIG. 1 shows a flow chart of the brightness correction method of the present invention.

Fig. 2 shows a schematic diagram of the brightness correction system of the present invention.

Detailed ways

FIG. 1 shows a flow chart of the brightness correction method of the present invention. The brightness correction method of the present invention is suitable for a display panel of a liquid crystal display. First, an input signal set is provided to the display panel to display a plurality of image areas (step S110 ), wherein each image area has a different display color.

The above input signal group is used to control the display position and display color of the image area, which can be provided by a control device in the display panel or by an external device. When the input signal group is provided by an external device, the external device can provide the input signal group to the display panel through a DVI (digital visual interface).

Generally, the image displayed by the liquid crystal display is composed of three primary colors (R, G, B). Therefore, when the brightness is corrected, the display panel can display three image areas through the input signal group, showing the three primary colors respectively. It is also possible to make the display panel display only two image areas, which respectively display RG, GB, or RB, so as to shorten the time for brightness correction. The brightness correction method of the present invention will be described below by taking three image regions as examples.

Next, provide the gray scale value of the first level (i=0) to each image area (step S120). Assuming that the above-mentioned liquid crystal display has an 8-bit data driver, 256 gray scale values will be generated. Each grayscale value has a corresponding Gamma voltage. The image area can present corresponding luminance according to the received gray scale value.

Then, the luminance presented by the three image regions is detected (step S130). Generally, the luminance can be obtained by contacting the three measuring ends of a measuring instrument one-to-one with the image area, or measuring the luminance of the image area in a non-contact manner.

Next, determine whether the grayscale value is greater than 255 (step S140). When the grayscale value received by the image area is not greater than 255, step S150 is executed to continue to provide another grayscale value to the image area. When the image area receives another grayscale value, step S130 is executed to continue detecting the brightness of the image area.

In step S150, n can be any number. When n is equal to 1, it means that 256 grayscale values are sequentially provided to the image area. When n is equal to 2, it means that an even-numbered gray scale value is provided to the image area. The smaller the value of n, the higher the accuracy of brightness correction of the display panel. When the value of n is larger, the brightness correction time of the display panel is shorter.

When the grayscale value received by the image area is greater than 255, step S160 is executed to record the detected luminance values in a calibration table when the image area receives different grayscale values. The operator can adjust the Gamma voltage corresponding to each gray scale value according to the luminance value in the calibration table (step S170).

Finally, the adjusted Gamma voltage is stored in a storage medium (step S190), wherein the adjusted Gamma voltage can be stored in the memory device of the display panel, so that whenever the liquid crystal display wants to display an image, it can be obtained by In a storage device (such as EEPROM), the Gamma voltage is captured.

Since the luminance value presented by the image area is recorded in a correction table when it receives different gray scale values, LCD manufacturers can adjust the gamma voltage corresponding to the above gray scale value according to different needs of customers. .

In addition, the brightness correction method of the present invention can be applied to a software for correcting the brightness of the display panel of each liquid crystal display.

Fig. 2 shows a schematic diagram of the brightness correction system of the present invention. As shown in the figure, the brightness calibration system includes a display panel 22 , a brightness detection device 24 , and a processing device 26 . The display panel 22 is used for displaying image areas 221 - 223 .

The image areas 221 - 223 have different display colors respectively. Generally, images displayed by liquid crystal displays are composed of three primary colors (R, G, B). For the convenience of illustration, the display panel in FIG. 2 shows three image areas 221 - 223 , which respectively present three primary colors. However, it is also possible to make the display panel display only two image areas, which respectively display RG, GB, or RB, so as to shorten the time for brightness correction.

The luminance detection device 24 (for example, a color analyzer) has measuring terminals 241-243, and detects the luminances of the image regions 221-223 corresponding to different grayscale values in a one-to-one manner in a contact or non-contact manner. , wherein the above-mentioned gray scale values have corresponding Gamma voltages respectively. In FIG. 2 , the measurement terminals 241 - 243 detect the luminance presented by the image areas 221 - 223 in a contact manner.

The processing device 26 (such as a desktop computer) adjusts the Gamma voltage corresponding to the above-mentioned grayscale value according to the luminance value detected by the luminance detection device 24 . The adjusted Gamma voltage can be stored in a storage medium (such as EEPROM) of the display panel 22 .

In addition, in FIG. 2 , the processing device 26 can provide an input signal group to the display panel 22 through the DVI connection line 28 to define the display positions and display colors of the image areas 221 - 223 . The above input signal group can also be provided by a control element (not shown) in the display panel 22 .

The operating principle of the brightness correction system of the present invention will be described in detail below. Please refer to FIG. 2 , firstly, the processing device 26 is coupled to the display panel 22 through the DVI cable 28 for setting the display positions of the image areas 221 - 223 on the display panel. Next, the processing device 26 provides a grayscale value to the display panel 22 through the DVI connection line 28 , so that the image areas 221 - 223 have different display colors.

The brightness detection device 24 contacts the measuring ends 241 - 243 with the image areas 221 - 223 to detect the brightness of the image areas 221 - 223 , and outputs the detected brightness to the processing device 26 . The processing device 26 then provides another grayscale value to the display panel 22 .

The processing device 26 integrates the luminance detected by the luminance detection device 24 and the gray scale value output by itself into a look-up table. Manufacturers of liquid crystal displays can adjust the brightness of the image area by adjusting the gamma voltage corresponding to the gray scale value in the calibration table according to different needs of customers. The adjusted Gamma voltage can be stored in a storage medium (not shown) of the display panel 22 .

Since the present invention measures the luminance of multiple image regions simultaneously, the time for Gamma voltage correction can be greatly reduced to 2 minutes. When the brightness detection device only detects every five gray scale values, the time for Gamma voltage correction can also be shortened. When the time for Gamma voltage calibration is greatly reduced, Gamma voltage calibration can be performed simultaneously while producing the display panel. After the Gamma voltage correction is performed on each display panel, the possibility of different hue, color shift, or color temperature deviation of the display panel can be reduced.

Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the present invention The scope of protection of the invention should be defined by the appended claims.

Claims (23)

1. A brightness correction method, applicable to a display panel, the above-mentioned brightness correction method, comprising: In the display panel, a plurality of image areas are displayed according to display colors, wherein the display color of any image area is different from the display colors of the remaining image areas; Detecting luminance values presented by the image region corresponding to different grayscale values, wherein the grayscale values respectively have corresponding Gamma voltages; and According to the detected luminance value, the Gamma voltage corresponding to the gray scale value is adjusted. 2. The brightness correction method as claimed in claim 1, further comprising providing an input signal group to the display panel for defining the image area. 3. The brightness correction method according to claim 2, wherein the input signal group is used to indicate the display position and display color of the image area. 4. The brightness correction method according to claim 2, wherein the input signal set is provided by an external device. 5 . The brightness calibration method according to claim 4 , wherein the external device is coupled to the display panel through a DVI cable. 6. The brightness correction method according to claim 2, wherein the input signal set is provided by a control element in the display panel. 7. The brightness correction method according to claim 1, wherein the brightness value of the image area is obtained by contacting a plurality of measuring ends of a measuring instrument to the image area one by one. 8. The calibration method according to claim 1, wherein the luminance value of the image area is obtained by detecting the image area one by one with a plurality of measuring ends of a measuring instrument in a non-contact manner. have to. 9. The calibration method according to claim 1, further comprising recording the adjusted Gamma voltage in a calibration table. 10. The calibration method according to claim 9, further comprising: storing the calibration table in a storage medium. 11. The calibration method according to claim 10, wherein the storage medium is located in the display panel. 12. The calibration method according to claim 10, wherein the storage medium is an EEPROM. 13. The calibration method according to claim 1, wherein the display colors presented by the image areas are red, green and blue respectively. 14. A brightness correction system comprising: A display panel for displaying a plurality of image areas according to display colors, wherein the display color of any image area is different from the display colors of the rest of the image areas; A luminance detection device for detecting the luminance values presented by the image area corresponding to different gray scale values, wherein the gray scale values have corresponding Gamma voltages; and A processing device adjusts the Gamma voltage corresponding to the grayscale value according to the detected luminance value. 15. The brightness correction system according to claim 14, wherein the processing device provides an input signal set to the display panel for defining the image area. 16. The brightness correction system according to claim 15, wherein the input signal group is used to indicate the display position and display color of the image area. 17. The brightness calibration system as claimed in claim 14, wherein the processing device is coupled to the display panel through a DVI cable. 18. The brightness correction system as claimed in claim 15, wherein the display panel further comprises a control element for providing the set of input signals. 19 . The brightness calibration system according to claim 14 , wherein the brightness detection device has a plurality of measuring terminals, which contact the image area one by one to detect the brightness value of the image area. 20. The brightness correction system according to claim 14, wherein the brightness detection device has a plurality of measurement terminals for one-to-one detection of the brightness value of the image area in a non-contact manner. 21. The brightness correction system according to claim 14, wherein the display panel further comprises a storage medium for storing the adjusted Gamma voltage. 22. The brightness calibration system as claimed in claim 21, wherein the storage medium is an EEPROM. 23. The brightness correction system according to claim 14, wherein the display colors presented by the image areas are red, green and blue respectively.

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