TWI895770B - Gamma voltage adjustment method and display debugging system - Google Patents

Abstract

This invention primarily discloses a gamma voltage adjustment method. The method first measures a plurality of tuning data corresponding to a plurality of binding points and converts the tuning data into a plurality of tuning RGB data sets, where the plurality of binding points correspond to a plurality of gamma voltage sets. Next, a selected target data set is converted into a target RGB data set. An interpolation operation is then performed on the two tuning RGB data sets to generate a target gamma voltage set corresponding to the target RGB data set. Finally, the calculated target gamma voltage set is burned into a display driver chip of the display. The method of the present invention primarily utilizes mathematical calculations to obtain the target gamma voltage sets, eliminating the need for repetitive, complex steps such as chip programming, display panel driving, panel measurement, and target value matching. Therefore, it can be used for pre-production gamma testing of various displays that include display panels and display driver chips.

Description

Gamma voltage adjustment method and display debugging system

The present invention relates to the technical field of display devices, and more particularly to a gamma voltage adjustment method for a display debugging system.

Figure 1 is a block diagram of a conventional display. As shown in Figure 1, the display 1a primarily comprises a display panel 11a comprising M×N pixels and at least one display driver chip 12a, where M and N are positive integers. During normal operation, the display driver chip 12a receives display data from a host computer 2a (e.g., an application processor in a smartphone) and then drives the display panel 11a based on the display data. Electronic engineers familiar with the design and manufacture of the display driver chip 12a will understand that the display driver chip 12a has a gamma voltage generating unit 121a, and the gamma voltage generating unit 121a is used to generate M×N sets of gamma voltages corresponding to the M×N pixels, so that a source drive circuit within the display driver chip 12a drives the display panel 11a according to the M×N sets of gamma voltages.

When the display panel 11a is driven to display an image, the user can change the display mode of the display 1a to a normal mode, a low color temperature mode, a game mode, or a movie mode. At this time, the display driver chip 12a changes the register value, thereby adjusting a set of center gamma voltages ( , , ), so that the gamma voltage generating unit 121a adjusts each set of gamma voltages correspondingly according to the central gamma voltage set.

However, after completing the transformation of the central gamma voltage and adjusting each set of gamma voltages, the display driver chip 12a cannot determine whether the color coordinates and brightness of the image displayed by the display panel 11a meet the target color coordinates and target brightness. Therefore, before the display 1a is shipped, the manufacturer typically stores multiple sets of target gamma voltages corresponding to various display modes within the display driver chip 12a. Unfortunately, due to the nonlinear correlation between the gamma voltages of the display panel 11a and their corresponding display brightness, coupled with the multidimensionality of color space, it becomes difficult to find the corresponding color coordinates and brightness of the RGB gamma voltages. Therefore, it is necessary to develop an effective and high-precision gamma voltage adjustment method.

From the above description, it can be seen that a new gamma voltage adjustment method is urgently needed in this field.

The primary objective of this invention is to provide a gamma voltage adjustment method. The method first measures a plurality of tuning data corresponding to a plurality of binding points and converts the tuning data into a plurality of tuning RGB data sets, where the plurality of binding points correspond to a plurality of gamma voltage sets. Next, a selected target data set is converted into target RGB data. An interpolation operation is then performed on the two tuning RGB data sets to generate a target gamma voltage set corresponding to the target RGB data. Finally, the calculated target gamma voltage set is burned into a display driver chip of the display. As can be seen from the foregoing description, the method of the present invention primarily utilizes mathematical calculations to obtain the target gamma voltage sets. This eliminates the need for repetitive, complex steps such as chip programming, display panel driver, panel measurement, and target value matching. Therefore, it can be universally applied to pre-shipment gamma testing of various displays, including display panels and display driver chips.

To achieve the above objectives, the present invention provides an embodiment of a gamma voltage adjustment method, which is executed by a control unit to perform a gamma voltage adjustment operation on a display, wherein the display includes a display panel and at least one display driver chip. The gamma voltage adjustment method comprises the following steps: Performing a display drive operation to enable the display driver chip to drive the display panel to display an image based on a tuning gamma voltage set; wherein the tuning gamma voltage set includes a red gamma voltage digital value, a green gamma voltage digital value, and a blue gamma voltage digital value; Performing a measurement operation to obtain a calibration data from the image; wherein the calibration data includes a calibration color coordinate and a calibration brightness; Repeating the display driving operation and the measurement operation a plurality of times until a plurality of calibration data corresponding to a plurality of calibration gamma voltage sets has been measured; Converting each of the calibration data into a calibration RGB data; wherein the calibration RGB data includes a calibration red grayscale value, a calibration green grayscale value, and a calibration blue grayscale value; Performing a data conversion operation to convert target data into target RGB data; wherein the target data includes a target color coordinate and a target brightness, and the target RGB data includes a target red grayscale value, a target green grayscale value, and a target blue grayscale value; Performing a calculation operation to interpolate the two debug RGB data to generate a target gamma voltage set corresponding to the target RGB data; wherein the target gamma voltage set includes a target red gamma voltage digital value, a target green gamma voltage digital value, and a target blue gamma voltage digital value; and Repeat the aforementioned data conversion and calculation operations until a plurality of target gamma voltage sets corresponding to a plurality of target RGB data are obtained.

In one embodiment, the control unit converts the debugging data into the debugging RGB data by performing the following steps: Performing a first color space conversion operation to convert the debugging data in the xyY color space into intermediate data in the XYZ color space; and Performing a second color space conversion operation to convert the intermediate data into the debugging RGB data in the RGB color space.

In one embodiment, the control unit converts the debugging data into the debugging RGB data by performing the following steps: Performing a first color space conversion operation to convert the target data in the xyY color space into intermediate data in the XYZ color space; and Performing a second color space conversion operation to convert the intermediate data into the target RGB data in the RGB color space.

In one embodiment, the control unit uses the following equations (1) to (3) to complete the first color space conversion operation: · ... · ... · ... is the brightness, and (x,y) is the color coordinate.

In one embodiment, the control unit uses the following formula (4) to complete the second color space conversion operation: ··························· (4) Wherein, R is the red grayscale value, G is the green grayscale value, and B is the blue grayscale value.

The present invention also provides a display debugging system comprising a control device and a measurement device. The system is characterized in that the control unit executes a gamma voltage adjustment method to perform a gamma voltage adjustment operation on a display, wherein the display includes a display panel and at least one display driver chip. The gamma voltage adjustment method comprises the following steps: Executing a display driving operation to enable the display driver chip to drive the display panel to display an image based on a debugging gamma voltage set; wherein the debugging gamma voltage set includes a red gamma voltage digital value, a green gamma voltage digital value, and a blue gamma voltage digital value; Performing a measurement operation to obtain a calibration data from the image; wherein the calibration data includes a calibration color coordinate and a calibration brightness; Repeating the display driving operation and the measurement operation a plurality of times until a plurality of calibration data corresponding to a plurality of calibration gamma voltage sets has been measured; Converting each of the calibration data into a calibration RGB data; wherein the calibration RGB data includes a calibration red grayscale value, a calibration green grayscale value, and a calibration blue grayscale value; Performing a data conversion operation to convert target data into target RGB data; wherein the target data includes a target color coordinate and a target brightness, and the target RGB data includes a target red grayscale value, a target green grayscale value, and a target blue grayscale value; Performing a calculation operation to interpolate the two debug RGB data to generate a target gamma voltage set corresponding to the target RGB data; wherein the target gamma voltage set includes a target red gamma voltage digital value, a target green gamma voltage digital value, and a target blue gamma voltage digital value; and Repeat the aforementioned data conversion and calculation operations until a plurality of target gamma voltage sets corresponding to a plurality of target RGB data are obtained.

In one embodiment, the display panel is any one selected from the group consisting of an LCD panel, an OLED panel, an LED panel, a Micro-LED panel, and a QLED panel.

In one embodiment, the measuring device is any one selected from the group consisting of a CCD camera, a spectroradiometer, and a color analyzer.

In one embodiment, the control device is any one selected from the group consisting of a desktop computer, a laptop computer, an all-in-one computer, a tablet computer, and an industrial computer.

In one embodiment, the control unit converts the debugging data into the debugging RGB data by performing the following steps: Performing a first color space conversion operation to convert the debugging data in the xyY color space into intermediate data in the XYZ color space; and Performing a second color space conversion operation to convert the intermediate data into the debugging RGB data in the RGB color space.

In one embodiment, the control unit converts the debugging data into the debugging RGB data by performing the following steps: Performing a first color space conversion operation to convert the target data in the xyY color space into intermediate data in the XYZ color space; and Performing a second color space conversion operation to convert the intermediate data into the target RGB data in the RGB color space.

In one embodiment, the control unit uses the following equations (1) to (3) to complete the first color space conversion operation: · ... · ... · ... is the brightness, and (x,y) is the color coordinate.

In one embodiment, the control unit uses the following formula (4) to complete the second color space conversion operation: ··························· (4) Wherein, R is the red grayscale value, G is the green grayscale value, and B is the blue grayscale value.

In order to enable the Review Committee to further understand the structure, features, purpose, and advantages of the present invention, the following are attached with drawings and detailed descriptions of preferred specific embodiments.

FIG. 2 is a block diagram of a display debugging system applying a gamma voltage adjustment method of the present invention. As shown in Figure 2, the display debugging system 2 mainly includes: a measurement device 21 and a control device 22, wherein the measurement device 21 is configured to face a display panel 11, and the control device 22 is coupled to the measurement device 21 and at least one display driver chip 12 for driving the display panel 11 to display images. It should be understood that the display panel 11 and the at least one display driver chip 12 are the main structural units of a display 1, and the display panel 11 may be, but is not limited to, an LCD panel, an OLED panel, an LED panel, a Micro-LED panel, or a QLED panel. On the other hand, the measuring device 21 may be, but is not limited to, a CCD camera, a spectroradiometer or a color analyzer. Furthermore, the control device 22 may be, but is not limited to, a desktop computer, a notebook computer, an all-in-one computer, a tablet computer, or an industrial computer.

In particular, the present invention provides a gamma voltage adjustment method, which is executed by the control device 22 of the display debugging system 2, thereby performing a gamma voltage adjustment operation on the display 1 to find a target gamma voltage set corresponding to a gamma binding point, and storing the target gamma voltage set in the display driver chip 12. Figure 3 is a flow chart of the gamma voltage adjustment method of the present invention. As shown in FIG3 , the method flow first executes steps S1-S2: executing a display driving operation to enable the display driver chip 12 to drive the display panel 11 to display an image according to a debugging gamma voltage set, and then executing a measurement operation to measure a debugging data from the image. For example, if the image is a full grayscale 255 image, the debugging gamma voltage set includes a red gamma voltage digital value. =1020, a green gamma voltage digital value =1020 and a blue gamma voltage digital value =1020. Among them, 、 and is the register value. After the display driver chip 12a changes the register value, a gamma voltage generating unit 121 inside it will 、 and This generates corresponding red, green, and blue gamma voltages.

Next, the method proceeds to step S3: repeating the aforementioned display driving operation and the aforementioned measurement operation multiple times until a plurality of debugging data corresponding to the plurality of debugging gamma voltage sets has been measured. For example, the obtained plurality of debugging data is shown in Figure 4. Continuing, the method proceeds to step S4: converting each of the debugging data into a debugging RGB data set. Specifically, the control device 22 converts the debugging data into the debugging RGB data by performing the following steps: Performing a first color space conversion operation to convert the debugging data in the xyY color space into intermediate data in the XYZ color space; and Performing a second color space conversion operation to convert the intermediate data into the debugging RGB data in the RGB color space.

According to the design of the present invention, the test data includes a test color coordinate ( , ) and a brightness adjustment , and the debugging RGB data includes a debugging red grayscale value 1. Adjust the green grayscale value and a blue grayscale value Therefore, the control device 22 can use the following equations (1) to (3) to complete the first color space conversion operation, and use the following equation (4) to complete the second color space conversion operation: · ... · ... · ... ···················· (4)

In the above formulas (1) to (4), X, Y, and Z are tristimulus values. is the brightness, (x,y) is the color coordinate, R is the red grayscale value, G is the green grayscale value, and B is the blue grayscale value. And, ( , )as well as Where n is a positive integer representing the debug data corresponding to different binding points (i.e., debug gamma voltage sets). Finally, the 36 debug RGB data corresponding to the 36 debug gamma voltage sets shown in Figure 4 are shown in Figure 5.

As shown in Figure 3, the method flow then proceeds to step S5: performing a data conversion operation to convert target data into target RGB data. Specifically, the control device 22 converts the target data into target RGB data by performing the following steps: Performing a first color space conversion operation to convert the target data in the xyY color space into intermediate data in the XYZ color space; and Performing a second color space conversion operation to convert the intermediate data into the target RGB data in the RGB color space.

According to the design of the present invention, the target data includes a target color coordinate ( , ) and a target brightness ,in( , )as well as Where n is a positive integer (e.g., 1 to 36) to represent different target data. In addition, the target RGB data includes a target red grayscale value. , a target green grayscale value and a target blue-gray value Therefore, the control device 22 can also use the aforementioned equations (1) to (3) to complete the first color space conversion operation, and use the aforementioned equation (4) to complete the second color space conversion operation. Finally, the 36 target RGB data corresponding to the 36 target grayscale values shown in Figure 4 are shown in Figure 6.

As shown in FIG3 , the method flow then proceeds to step S6: performing a calculation operation to perform an interpolation operation on the two debug RGB data to generate a target gamma voltage set corresponding to the target RGB data. For example, as shown in FIG6 , when the target grayscale value is 255, the corresponding target RGB data is ( , , )=(280.77, 364.23, 441.09). Then, in Figure 5, we can find that 280.77 is between =286.87 and =279.48, so =280.77, =286.87, =279.48, =917 and =901 interpolation operation can calculate a target red gamma voltage digital value =904. Similarly, in Figure 5 we can find 364.23 between =372.02 and =343.72, so =364.23, =372.02, =343.72, =790 and =760 interpolation operation can calculate a target green gamma voltage digital value =782. Similarly, in Figure 5 we can find 441.09 between =453.31 and =415.57, so =441.09, =453.31, =415.57, =760 and =733 interpolation operation can calculate a target blue gamma voltage digital value =751.

As shown in FIG3 , the method flow then proceeds to step S7: repeating the aforementioned data conversion operation and the aforementioned calculation operation until a plurality of target gamma voltage sets corresponding to a plurality of target RGB data are obtained. It should be noted that each target gamma voltage set includes a target red gamma voltage digital value. , a target green gamma voltage digital value and a target green gamma voltage digital value Furthermore, after each target gamma voltage set is calculated, the target gamma voltage set is burned into the display driver chip 12. Of course, all 36 target gamma voltage sets can also be written into the display driver chip 12 after they are calculated.

Thus, the above description has completely and clearly explained a gamma voltage adjustment method of the present invention. Furthermore, it can be seen from the above description that the present invention has the following advantages:

(1) The present invention discloses a gamma voltage adjustment method, which is applied to a display debugging system including a measuring device and a control unit, and is executed by the control unit to perform a gamma voltage adjustment operation on a display. In particular, the method of the present invention first measures a plurality of debugging data corresponding to a plurality of binding points, and converts the plurality of debugging data into a plurality of debugging RGB data, wherein the plurality of binding points correspond to a plurality of gamma voltage groups, respectively. Then, a selected target data is converted into a target RGB data, and then an interpolation operation is performed on the two debugging RGB data to generate a target gamma voltage group corresponding to the target RGB data. Finally, the calculated target gamma voltage set is burned into a display driver chip of the display. As can be seen from the foregoing description, the method of the present invention primarily utilizes mathematical calculations to obtain each target gamma voltage set, eliminating the need for repeated, complex steps such as chip burning, display panel driving, panel measurement, and target value matching. Therefore, it can be universally applied to pre-shipment gamma testing of various displays that include display panels and display driver chips.

(2) Furthermore, the present invention discloses a display debugging system comprising a control device and a measuring device, wherein the control unit device executes the gamma voltage adjustment method of the present invention as described above to perform a gamma voltage adjustment operation on a display, thereby finding a gamma voltage set corresponding to a target gamma binding point, and then storing the gamma voltage set in a display driver chip of the display.

It must be emphasized that the aforementioned disclosure of this case is a preferred embodiment. Any partial changes or modifications that are derived from the technical ideas of this case and are easily inferred by those familiar with the art do not deviate from the scope of the patent rights of this case.

In summary, this case demonstrates significant differences from prior art in terms of purpose, means, and effectiveness. Furthermore, its first invention is practical and truly meets the patent requirements for invention. We earnestly request that the Review Commission examine this matter and grant a patent to this invention as soon as possible to benefit society. This is our utmost prayer.

1a: Display 11a: Display panel 12a: Display driver chip 121a: Gamma voltage generating unit 2a: Host computer 1: Display 11: Display panel 12: Display driver chip 121: Gamma voltage generating unit 2: Display debugging system 21: Measurement device 22: Control device S1: Executes a display driver operation to enable the display driver chip to drive the display panel to display an image based on a debug gamma voltage set. S2: Executes a measurement operation to obtain debug data from the image. S3: Repeat the aforementioned display driving operation and the aforementioned measurement operation multiple times until multiple adjustment data corresponding to the multiple adjustment gamma voltage sets are measured. S4: Convert each of the adjustment data into adjustment RGB data. S5: Perform a data conversion operation to convert a target data into a target RGB data. S6: Perform a calculation operation to interpolate the two adjustment RGB data to generate a target gamma voltage set corresponding to the target RGB data. S7: Repeat the aforementioned data conversion operation and the aforementioned calculation operation until multiple target gamma voltage sets corresponding to the multiple target RGB data are obtained.

Figure 1 is a block diagram of a conventional flat panel display; Figure 2 is a block diagram of a display debugging system that utilizes a gamma voltage adjustment method of the present invention; Figure 3 is a flow chart of the gamma voltage adjustment method of the present invention; Figure 4 is a table of 36 debugging data points; Figure 5 is a table of 36 debugging RGB data points; and Figure 6 is a table of 36 target RGB data points.

S1: Perform a display driving operation to enable the display driver chip to drive the display panel to display an image based on a tuning gamma voltage set. S2: Perform a measurement operation to obtain tuning data from the image. S3: Repeat the display driving operation and the measurement operation a plurality of times until a plurality of tuning data corresponding to a plurality of tuning gamma voltage sets has been measured. S4: Convert each of the tuning data into tuning RGB data. S5: Perform a data conversion operation to convert target data into target RGB data. S6: Perform a calculation operation to interpolate the two tuning RGB data to generate a target gamma voltage set corresponding to the target RGB data. S7: Repeat the aforementioned data conversion and calculation operations until multiple target gamma voltage sets corresponding to multiple target RGB data are obtained.

Claims (10)

A gamma voltage adjustment method is performed by a control unit to adjust the gamma voltage of a display, wherein the display includes a display panel and at least one display driver chip. The gamma voltage adjustment method comprises the following steps: Performing a display drive operation to enable the display driver chip to drive the display panel to display an image based on a tuning gamma voltage set; wherein the tuning gamma voltage set includes a red gamma voltage digital value, a green gamma voltage digital value, and a blue gamma voltage digital value; Performing a measurement operation to obtain a calibration data from the image; wherein the calibration data includes a calibration color coordinate and a calibration brightness; Repeating the display driving operation and the measurement operation a plurality of times until a plurality of calibration data corresponding to a plurality of calibration gamma voltage sets has been measured; Converting each of the calibration data into a calibration RGB data; wherein the calibration RGB data includes a calibration red grayscale value, a calibration green grayscale value, and a calibration blue grayscale value; Performing a data conversion operation to convert target data into target RGB data; wherein the target data includes a target color coordinate and a target brightness, and the target RGB data includes a target red grayscale value, a target green grayscale value, and a target blue grayscale value; Performing a calculation operation to interpolate the two debug RGB data to generate a target gamma voltage set corresponding to the target RGB data; wherein the target gamma voltage set includes a target red gamma voltage digital value, a target green gamma voltage digital value, and a target blue gamma voltage digital value; and Repeat the aforementioned data conversion operation and the aforementioned calculation operation until a plurality of target gamma voltage sets corresponding to a plurality of target RGB data are obtained, and these target gamma voltage sets are burned into the at least one display driver chip. The gamma voltage adjustment method of claim 1, wherein the control unit converts the adjustment data into the adjustment RGB data by performing the following steps: Performing a first color space conversion operation to convert the adjustment data in the xyY color space into intermediate data in the XYZ color space; and Performing a second color space conversion operation to convert the intermediate data into the adjustment RGB data in the RGB color space. The gamma voltage adjustment method of claim 1, wherein the control unit converts the target data into the target RGB data by performing the following steps: Performing a first color space conversion operation to convert the target data in the xyY color space into intermediate data in the XYZ color space; and Performing a second color space conversion operation to convert the intermediate data into the target RGB data in the RGB color space. The gamma voltage adjustment method as described in claim 2 or claim 3, wherein the control unit uses the following equations (1) to (3) to complete the first color space conversion operation: · ... · ... ············································· (3) ； Wherein, X, Y and Z are tristimulus values, is the brightness, and (x,y) is the color coordinate. The gamma voltage adjustment method as described in claim 4, wherein the control unit uses the following formula (4) to complete the second color space conversion operation: ················· (4) ; wherein R is the red grayscale value, G is the green grayscale value, and B is the blue grayscale value. A display debugging system includes a control device and a measurement device. The control device executes a gamma voltage adjustment method to perform a gamma voltage adjustment operation on a display, wherein the display includes a display panel and at least one display driver chip. The gamma voltage adjustment method comprises the following steps: Executing a display drive operation to enable the display driver chip to drive the display panel to display an image based on a debugging gamma voltage set; wherein the debugging gamma voltage set includes a red gamma voltage digital value, a green gamma voltage digital value, and a blue gamma voltage digital value; Performing a measurement operation to obtain a calibration data from the image; wherein the calibration data includes a calibration color coordinate and a calibration brightness; Repeating the display driving operation and the measurement operation a plurality of times until a plurality of calibration data corresponding to a plurality of calibration gamma voltage sets has been measured; Converting each of the calibration data into a calibration RGB data; wherein the calibration RGB data includes a calibration red grayscale value, a calibration green grayscale value, and a calibration blue grayscale value; Performing a data conversion operation to convert target data into target RGB data; wherein the target data includes a target color coordinate and a target brightness, and the target RGB data includes a target red grayscale value, a target green grayscale value, and a target blue grayscale value; Performing a calculation operation to interpolate the two debug RGB data to generate a target gamma voltage set corresponding to the target RGB data; wherein the target gamma voltage set includes a target red gamma voltage digital value, a target green gamma voltage digital value, and a target blue gamma voltage digital value; and Repeat the aforementioned data conversion operation and the aforementioned calculation operation until a plurality of target gamma voltage sets corresponding to a plurality of target RGB data are obtained, and these target gamma voltage sets are burned into the at least one display driver chip. The display debugging system of claim 6, wherein the control unit converts the debugging data into the debugging RGB data by performing the following steps: Performing a first color space conversion operation to convert the debugging data in the xyY color space into intermediate data in the XYZ color space; and Performing a second color space conversion operation to convert the intermediate data into the debugging RGB data in the RGB color space. The display debugging system of claim 6, wherein the control unit converts the target data into the target RGB data by performing the following steps: Performing a first color space conversion operation to convert the target data in the xyY color space into intermediate data in the XYZ color space; and Performing a second color space conversion operation to convert the intermediate data into the target RGB data in the RGB color space. In the display debugging system of claim 7 or claim 8, the control unit utilizes the following equations (1) to (3) to complete the first color space conversion operation: · ... · ... ············································· (3) ； Wherein, X, Y and Z are tristimulus values, is the brightness, and (x,y) is the color coordinate. The display debugging system as claimed in claim 9, wherein the control unit uses the following formula (4) to complete the second color space conversion operation: ················· (4) ; wherein R is the red grayscale value, G is the green grayscale value, and B is the blue grayscale value.