JP2001350456A - Display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for easily detecting a gamma characteristic of a display device. SOLUTION: A graphic 1210 consisting of a graphic 1211 and a graphic 1212 is arranged in columns and rows, and a color in which the graphic 1211 is painted out is displayed in one direction with the luminance being changed, and the graphic 1212 is also painted out in the same color and displayed on a screen in the direction perpendicular to the graphic 1211 with the luminance being changed. This display picture is scrolled over plural pieces of displays. When the display device has a small gradient in the gamma characteristic, the boundary between the graphic 1211 and the graphic 1212 becomes obscure, therefore, it is possible to display the gamma characteristic of the display device by a distribution form of a pseudo contour shape of the above display graphics.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a method for easily detecting and correcting a gamma characteristic of a display device.

[0002]

2. Description of the Related Art A display device is a device for inputting an image electric signal including color information and converting the same into light. The characteristics of this electro-optical conversion, that is, the gamma characteristics are different for each display device. There is. FIG. 2 shows an example of a gamma characteristic in order to explain individual differences in display colors of the display device. The gamma characteristic takes the image electric signal 201 on the horizontal axis and the light output 501 on the vertical axis,
The relationship is plotted.

A method of providing a circuit for correcting gamma characteristics in a display device and adjusting the parameters thereof to correct individual differences of the display device has been used. Examples of this are disclosed in JP-A-6-339148, JP-A-6-18841,
There are JP-A-9-135354 and JP-A-8-275001.

[0004]

In the prior art, it was necessary to use a measuring instrument for measuring the light output in order to obtain a gamma characteristic. Also, the gamma characteristic is for each level of the input signal,
Measurements need to be made for each of the three primary colors. Further, in a large-screen display device such as a multi-screen, it is necessary to measure each position and each three primary colors.

[0005] For this reason, in order to perform strict adjustment, it is necessary to perform a large number of measurements, it takes time for the adjustment, and it is necessary to prepare a dedicated measuring instrument such as a luminance meter. In addition, since the light output is measured by the measuring instrument, the obtained result does not always match the human sense. There is also a case where after the adjustment, readjustment by the human eye is performed.

SUMMARY OF THE INVENTION It is an object of the present invention to measure the color unevenness of the entire screen with a small number of operations without requiring a dedicated measuring device, and to provide a display device for correcting gamma characteristics using the same. .

[0007]

In order to solve the above-mentioned problems, human perception can comprehensively judge the whole, judging the color difference between two adjacent areas, and being sensitive to geometrical movement. In view of the above, an adjustment method using a test pattern that can easily determine a difference in color with human eyes is provided.

According to the present invention, in a display device provided with an image signal generating device having color conversion tables for R, G, and B primary colors, two filled figures having different luminances are arranged orthogonally while changing luminance, and The gamma characteristic of the display device is detected from a pseudo contour shape that expands as the boundary becomes unclear.

[0009] Further, the method is characterized in that a change in the pseudo contour shape is visually obtained by scrolling the array. Further, the display color is corrected by performing inverse gamma correction based on the outline shape.

[0010]

FIG. 1 shows a configuration of a display device according to the present invention. The image generation device 101 is connected to the display device 301 via the image signal 201, and the light output 501 causes the screen 40
Display 1 image. The image generation device 101 is a drawing operation device
111, frame memory 121, red color conversion table 131R and D / A converter 141R, green color conversion table 131G and D / A converter 141G, blue color conversion table 131B and D / A converter 141
B and a storage device for further storing image data 161
151 and input device 171, network interface
181.

The drawing operation device 111 reads out the image data 161 from the storage device 151 and writes it into the frame memory 121. In addition, an image pattern such as a line segment, a figure, and a character is generated, and is similarly written in the frame memory 121. The drawing calculation function includes a display data display function, a display moving function, a display color changing function, a color adjustment function, and the like.

The frame memory 121 has memories for the number of pixels displayed by the display device 301, and stores image data composed of color information for each pixel. This image data is read out one pixel at a time in accordance with the sweep direction of the display device 301, converted into color information for each of the three primary colors by the color conversion tables 131R, 131G, and 131B, and converted into image information by the D / A converters 141R, 141G, and 141B. The analog RGB signals 201R, 201G, and 201B constituting the signal 201 are output.

FIG. 3 shows test pattern image data 161.
Will be described. The image data 161 includes a rectangle 1211 displayed on the bottom of the screen and a circle displayed on the top of the screen.
It is configured by arranging a plurality of figures 1210 consisting of 1212 vertically and horizontally. Note that the circle 1212 can be replaced by other figures 1213 and 1214. The rectangle 1211 has the same fill color in the horizontal direction, and has a color whose luminance increases from 0 to 9 from bottom to top. The circle 1212 has the same fill color in the vertical direction, and has a color that increases in luminance from 0 to 9 from left to right. In this figure, the numerical value of the color is described in the figure. By writing the image data 161 into the frame memory 121, the image is displayed on the screen 401 by the display device 301 as an image.

FIG. 4 shows a screen 4 displayed on the screen 401.
015 is shown. The numerical value described in the figure indicates the value of the light output 501. The gamma characteristic of the display device 301 at this time is shown in FIG.
It is assumed that the value of the input image signal 201 and the light output 501 are linear and have the same gamma characteristic 3001 as shown by the broken line. Then, on a screen 4015 displayed on the screen 401, an arrangement of a graphic 4010 including a rectangle 4011 and a circle 4012 of the same color combination as the image data 161 is displayed. That is, the numerical values in the figure match those in FIG.

At this time, figures 4010 in which the fill colors of the rectangle 4011 and the circle 4012 match each other are arranged diagonally. This shape
For 4010, the boundary between the rectangle 4011 and the circle 4012 is not visible,
It is recognized as a figure different from the other figures 4010 with sharp boundaries. For this reason, a pseudo contour figure 4017 as shown by hatching
It is recognized as.

On the other hand, if the characteristic is such as the gamma characteristic 3011 in FIG. 2, the slope becomes smaller as the input image signal becomes larger. The screen display at this time is shown in FIG. In this figure as well, the value of the light output 501 is entered in the figure.

In the gamma characteristic 3011, when the value of the image signal 201 is 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9, the light outputs 501 are 0, 1.5, and 3 respectively. , 6, 7,
Are converted to 8.3, 8.5, 9, 9. Therefore, the rectangle
When the input image signals 4011 and 4012 are both 6 or more, the difference between the values of the light output 501 is small, and
Becomes Therefore, the pseudo contour figure 4017 in this case is displayed such that the width increases as it goes to the upper right.

In this example, the rectangle 4011 is a circle 4012 from bottom to top.
Is shaded from left to right. What is important here is that the shading of the figure displayed on the front is orthogonal to the shading direction of the figure displayed on the back. For example, if the top-most drawing is shaded from the lower left direction to the upper right direction, the foreground figure can be formed with the shading from the direction orthogonal thereto, that is, from the upper left to the lower right. In this case, the pseudo contour figure is displayed in the vertical or horizontal direction.

According to this embodiment, as shown in FIG. 5, by arranging two filled figures having different luminances while changing the luminance, a pseudo contour shape generated depending on whether the boundary between the filled figures is clear or not is obtained. Is displayed. Whether or not the boundary between two filled figures having different luminances is clear is determined by the gradient of the gamma characteristic of the display device. Therefore, the pseudo contour shape allows the gamma characteristic of the display device to be known. Therefore, it is possible to visually measure the gamma characteristic of the display device without using a measuring device for measuring the light output of the display device in order to measure the gamma characteristic.

FIG. 6 shows a processing flow of the drawing arithmetic unit 111. In step 701, an input from the keyboard 171 or the like is read, and in step 702, image data 161 of a color corresponding to the input data is read into the frame memory 121. The image data 16 read into the frame memory 121 in step 703
1 is displayed on the screen 401.

Next, at steps 704 and 705,
The command input from the keyboard 171 is determined, and the process proceeds to scroll processing 706 or color conversion data change processing 707 according to the input data.

FIG. 7 shows an embodiment of the adjustment. An adjustment pattern is displayed on the screen, and an adjustment window 901 is displayed at the lower right as an adjustment tool. This adjustment tool is a gamma characteristic operation unit that operates the gamma characteristic with a mouse etc.
902, an operation unit 903 for scrolling the adjustment pattern up, down, left and right, and an operation unit (command button) 9011 for reading and storing the adjusted parameters.

At the time of adjustment, an adjustment window 901 is displayed, and an adjustment pattern is displayed from the command button 9011. Next, the input device 171 such as a mouse is used to scroll the adjustment pattern to an arbitrary position. If the pseudo contour figure 4017 finds a large place during scrolling, the scrolling is stopped and the operation shifts to the adjustment operation. The adjustment is performed by using the operation unit 902 and changing the gamma characteristic 9021 while checking it with the cursor 9022 of the input device.

The operation of the cursor 9022 directly operates the gamma characteristic 9021 while pressing the button of the mouse 171. At this time, every time the gamma characteristic operation unit 902 is operated, the pseudo contour figure 4017 of the adjustment pattern is expanded or narrowed, but the operation unit 902 is operated so as to be in the narrowing direction 904.
That is, when the display device has the gamma characteristic 3011 shown in FIG. 2, the characteristic of the display data output from the operation unit 902 is adjusted to a normal characteristic by obtaining the inverse characteristic of the gamma characteristic 3011. After the adjustment is completed, the pseudo contour figure 4017 is moved to another place where the pseudo contour figure 4017 is large, and the adjustment is performed. Further, the adjustment can be performed even for R, G, and B single colors.

FIG. 8 shows the scroll processing. In step 801, the image data 16 in the frame memory 121 is read.
Display 1. Next, in step 802, the process waits until a predetermined time has elapsed.

FIG. 9 illustrates the pixel movement. The figure is copied to a position shifted two columns to the left for each column. The left two columns that extend beyond the screen area are copied to the right end.

FIG. 10 shows a specific process of the gamma characteristic operation unit. The gamma characteristic operation unit 902 sets defaults in the conversion table 1010 corresponding to the normal characteristic 3010. When the gamma characteristic operation unit 902 is operated by the input device 171,
The conversion value of the conversion table 1011 is changed according to, for example, the conversion characteristic 3011. That is, from the start coordinates (X0, Y0) of the button press of the input device 171 such as a mouse to the end coordinates (X
(1, Y1) is calculated, a characteristic curve 3011 is created, and a conversion value for each luminance corresponding to the curve 3011 is stored as a table 1011. The stored data is reflected in the conversion tables 131R, G, and B for each color in the image generation device.

That is, the display data output from the frame memory 121 is displayed on the display device 301 after the conversion corresponding to the characteristic 3011 is performed in the conversion table 131. Similarly, if the gamma characteristic operation unit 902 is changed to the characteristic 3012 by the input device 171, the conversion table can be changed as described above, and the display characteristics can be changed.

As described above, according to the present embodiment, by arranging two filled figures while changing the luminance, the two filled figures are scrolled together with the pseudo contour shape generated depending on whether or not the boundary between the filled figures is clear, and the gamma of the display device is adjusted. The difference in the characteristics can be visually represented as a change in the pseudo-contour shape, specifically, as a wavy display, showing positional gamma characteristic variations. This makes it possible to measure the difference in gamma characteristics depending on the display position in a short time without measuring the gamma characteristics for each display position.

Further, an operation is performed so that the pseudo contour shape reflecting the gamma characteristic is in a direction in which the pseudo contour shape is narrowed. That is, the gamma characteristic of the display device can be obtained as a gamma inverse characteristic to the characteristic of the display data output by the operation unit 902, and the characteristic can be adjusted to a normal characteristic.

[0031]

According to the present invention, according to the gamma characteristic,
A pseudo contour shape in which the boundary of the filled figure becomes unclear can be used as the adjustment pattern, and the variation in the position gamma characteristic can be visually represented. In addition, it is possible to adjust the characteristics of the display data to the normal characteristics by obtaining the gamma inverse characteristics with respect to the gamma characteristics of the display device.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a display device according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an example of a gamma characteristic.

FIG. 3 is an explanatory diagram showing a basic configuration of a test pattern.

FIG. 4 is an explanatory diagram showing an example of a test pattern.

FIG. 5 is an explanatory diagram showing another example of a test pattern.

FIG. 6 is a flowchart showing the processing of the drawing operation processing device.

FIG. 7 is a screen view showing an adjustment tool window.

FIG. 8 is a flowchart showing scroll processing.

FIG. 9 is an explanatory diagram of pixel movement.

FIG. 10 is an explanatory diagram showing an image of a gamma characteristic operation unit.

[Explanation of symbols]

101: Image generation device, 111: Image operation device, 121: Frame memory, 131: Conversion table, 141: D / A converter, 151
… Storage device, 161… image data, 171… input device, 201…
Image signal, 301: display device, 401: screen, 501: light output.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 9/69 H04N 9/69 17/02 17/02 Z F term (Reference) 5C061 BB03 5C066 AA03 CA17 DA09 EC05 GA01 GA22 GA33 KE09 KF05 KL13 KM11 5C082 AA13 BA14 BA34 BA35 BB51 CA11 CA12 CA72 CB05 CB08 DA51 DA71 EA20 MM09 MM10

Claims (3)

[Claims] 1. A display device comprising an image generation device having a color conversion table of three primary colors of R, G, and B, wherein two filled figures having different luminances are arranged orthogonally while changing luminance, and a boundary between the filled figures is changed. A display device for detecting a gamma characteristic of a display device from a pseudo contour shape that expands as the image becomes unclear. 2. The display device according to claim 1, wherein the array is scrolled to determine a change in the pseudo contour shape from a visual angle. 3. The display device according to claim 1, wherein a display color is corrected by performing inverse gamma correction based on the outline shape.