JP2005121724A - Adjusting method of flat display apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flat display apparatus in which luminance change of a display pixel of each pixel is small and a high quality image is displayed in the flat display apparatus in which a plurality of unit flat display elements are arranged. <P>SOLUTION: In an adjusting method of the flat display apparatus, after imaging a display image over a whole display face as an intermittent display at equal intervals in line in vertical or horizontal direction, an operation for sequentially moving the display pixel to an adjoining pixel and imaging the pixel, is performed over the number of times larger than the number of pixels between adjoining intermittent display pixels by one time, and all pixels on the display face are imaged and thereafter, obtained image data are arranged based on pixel arrangement information and a composite whole display face image data is formed and a pixel reference set value is set from the arranged pixel information. A correction factor of each pixel is calculated while the obtained set value is compared with the arranged pixel information and the correction factor is stored in a memory for correction factors and a video signal which is supplied to each pixel of the flat display apparatus is adjusted by the correction factors loaded from the memory for correction factors. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for adjusting luminance and the like for improving display quality of an image display device in which a plurality of unit display devices are arranged, and more particularly to a flat display device characterized by accurate measurement of the luminance of each pixel. It relates to the adjustment method.

  A flat display device in which a large-area screen is formed by arranging a large number of unit display devices such as small plasma display devices is a variation in brightness between each unit display device and each unit display device, and between adjacent unit display devices. There are many factors that degrade display quality, such as discomfort at the seam. These can greatly improve the display quality by correcting the luminance and chromaticity by adjusting the electric signal supplied to each unit display device.

Various methods for reducing luminance variations among units have been proposed as methods for correcting luminance unevenness in conventional large multi-screen display devices.
Each of these brightness adjustment methods adjusts the brightness or the like for each constituent unit, and does not adjust the variation in the pixels on the entire display surface, so there is a limit to improving the display quality.
Therefore, the present inventors have filed as Japanese Patent Application No. 2003-272038 a method for capturing the entire display screen of a display device in which a plurality of unit display devices are arranged, capturing data of all pixels, and correcting the luminance of all pixels.
This method is to adjust the luminance of the entire display surface, and the display quality is greatly improved. However, in some cases, the display quality is not properly corrected.
The present inventors have studied the problem that the luminance correction is not properly performed, and found that one of the causes is that the luminance of each pixel may not be accurately measured during measurement.

  The present invention accurately measures the quality of a display image in a flat display device in which a plurality of unit flat display elements are arranged so that the luminance of each display pixel is not affected by adjacent pixels, and based on the measurement. An object of the present invention is to provide an image adjustment method with excellent image display characteristics for adjusting the entire display surface.

An object of the present invention is to provide a method for adjusting a flat display device, in which a display image is imaged over the entire display surface as an intermittent display at equal intervals in a vertical or horizontal direction, and then the display pixels are sequentially moved to adjacent pixels. After the imaging operation is performed once more than the number of pixels between adjacent intermittent display pixels to image all pixels on the display surface, the obtained imaging data is arranged based on the pixel arrangement information and synthesized. Create all display surface image data, set the pixel reference setting value from the arranged pixel information, compare the obtained setting value with the arranged pixel information, calculate the correction coefficient of each pixel, and use the correction coefficient for the correction coefficient This can be solved by an adjustment method for a flat display device in which a video signal stored in a memory and supplied to each pixel of the flat display device is adjusted by a correction coefficient called from the correction coefficient memory.
Further, in the adjustment method of the flat display device, the number of pixels of the adjacent display pixel interval is set to a size in which the luminance of the adjacent pixels displayed simultaneously is distinguished and measured.
Further, the method for adjusting the flat display device described above, wherein the display pixel measuring means includes a plurality of light measurement pixels arranged, and the measurement data obtained by the plurality of light measurement pixels is integrated into display pixel data. It is.

In the adjustment method of the flat display device, the process from the imaging by the imaging unit to the adjustment by the video signal adjusting unit is repeatedly performed after the video signal is adjusted by the correction coefficient called from the correction coefficient memory.
In addition, when the intermittently displayed image is captured, the flat display that captures the data of each intermittent display pixel by reducing the moire by shifting the focus from the in-focus position within a range in which the intermittently displayed adjacent images are distinguished and captured. This is an apparatus adjustment method.
At least one of before and after the adjustment of the flat display device, the entire surface of the flat display device is displayed and the entire display surface is imaged, and the obtained imaging data is arranged based on the pixel arrangement information, Compare with the pixel reference value, calculate the correction coefficient of each pixel, store the correction coefficient in the correction coefficient memory, and adjust the video signal supplied to each pixel of the flat panel display device using the correction coefficient called from the correction coefficient memory It is the adjustment method of the said flat type display apparatus performed after having performed.

Further, in the adjustment method of the flat display device described above, the image capturing process is repeated a plurality of times by shifting the moire phase of the display image of the entire display surface image data, and the obtained image data is summed and averaged to obtain measurement data. is there.
In the adjustment method of the flat display device, an image pickup means that can move in the vertical or horizontal direction on the display surface of the flat display device and can simultaneously image a horizontal or vertical row is installed, and the pixels on the display surface are Alternatively, the image data is moved and displayed one by one in the vertical direction, and the image data obtained based on the pixel arrangement information is obtained by repeating the movement and imaging of the imaging unit in synchronization with the displayed pixels and imaging all the display pixels. To create composite total display surface image data, set the pixel reference setting value from the arranged pixel information, compare the obtained setting value with the arranged pixel information, calculate the correction coefficient of each pixel and correct This is a method for adjusting a flat display device in which coefficients are stored in a correction coefficient memory and a video signal supplied to each pixel of the flat display device is adjusted by a correction coefficient called from the correction coefficient memory.

  According to the present invention, in a large-sized image display device in which a large number of unit flat display elements are arranged, information on each pixel of the image display device can be accurately measured without being affected by adjacent pixels. It is possible to adjust the image with high accuracy by adjusting the composed display image thus configured in comparison with the reference pixel.

  The present invention examines the problem that the display image is not properly corrected, and finds that one of the causes is that the luminance of each pixel may not be accurately measured during measurement. In particular, when the brightness of adjacent pixels changes steeply, when measuring with full-screen display, proper adjustment may not be performed only by correction based on measurement data of adjacent pixels. It has been found that a better display image can be obtained by combining the adjustment by measuring the entire display surface and the method of accurately measuring the luminance of each pixel of the present invention.

The present invention will be described below with reference to the drawings.
FIG. 1 is a diagram illustrating a flat display device of the present invention.
A flat display device 1 described with reference to FIG. 1 includes a unit flat display element 5 including a large number of plasma display elements.
A marker 7 formed on the display surface of the flat display device 1 and indicating the periphery of the display image is picked up by an image pickup means 11 such as a CCD camera arranged at a predetermined distance from the display surface of the flat display device. The
After the position of the periphery of the display surface is determined by imaging the marker 7, all the pixels of the flat display device are displayed at regular intervals like the intermittent display pixel 9 for every N pixels, and the image is first captured with the marker. The display surface is imaged at the same magnification.

The data imaged by the imaging means is wider than the display pixels, and the resolution of the imaging means may not match the resolution of the display pixels.
Therefore, in order to accurately measure the luminance, the column image data 12 of one column of display pixels is created by integrating the imaging data on both sides with the highest luminance portion as the center.
An interpolated arrangement image corresponding to the information of each pixel is formed on the basis of the image information indicating the size of the column image data 12 of each column of display pixels determined by the image information by the marker 7 and the address. Subsequently, one full display surface image data is formed by the full display surface image forming means 13 from the interpolation arrangement data of each intermittent display image.
Reference luminance information is set from all the interpolated display image data, and the difference from the reference luminance information is calculated by the luminance distribution correction coefficient processing circuit 15 and stored in the correction coefficient memory 17.

On the other hand, after the video input signal 19 is corrected by the γ correction circuit 21, the luminance signal of each pixel is corrected in the luminance correction arithmetic circuit 23 based on the correction coefficient for each pixel stored in the correction coefficient memory 17. The
Next, the luminance-corrected data is expanded in the video signal frame memory 25 and transmitted to the display data array conversion processing circuit 27 to be data corresponding to each unit flat display element 5.
Then, the data is transmitted from the display data transmission circuit 29 to the display control circuit 31 of the unit flat display elements 5-1 to 5 -n, and is driven from the display control circuit to the address drive circuit 33, the scan drive circuit 35, and the sustain drive circuit 37. A signal is transmitted and an image is displayed.
Each drive circuit is supplied with an address drive voltage Va, a sustain drive voltage Vs, a scan drive voltage Vw, and the like from a power supply 39 formed of a DC / DC converter.

FIG. 2 is a diagram illustrating a flat display device of the present invention.
The flat display device 1 of the present invention is configured by arranging n rows of display elements in a row of element numbers U11 to U1m of the unit flat display elements 5, and one single flat display element 5 is used for each. A flat display device 1 is formed.
Each unit flat display element 5 transmits display data from the display data transmission circuit 29 and displays one image.

FIG. 3 is a diagram for explaining the luminance adjustment procedure of the pixel of the flat display device of the present invention.
Using unit flat display elements formed of 64 pixels × 64 pixels × R, G, and B pixels, eight unit flat display elements are arranged in the vertical direction and 10 in the horizontal direction, for a total of 80 units. A flat display device having a total number of pixels of 640 × 512 × R, G, B will be described as an example.
In S1, markers provided at the four vertices on the outermost periphery of the display pixel of the flat display device are displayed and imaged by the imaging means. The size of the display image is detected based on the four captured vertices.
In place of the markers arranged at the four vertices for detecting the size of the image, the size of the image may be detected by a method of causing only one row of the outermost periphery to emit light.

In S2, intermittent display is performed by dividing all display pixels at equal intervals. For example, a flat display device in which 64 × 64 ×× 3 (R, G, B) unit flat display elements are arranged in the height direction and 10 in the horizontal direction is arranged with N pixels at equal intervals in the column direction. Perform intermittent display.
In S3, the first image is captured at the same measurement magnification as when the previous marker was captured. Next, the display pixel is moved to an adjacent pixel, and a second image is captured. As described above, by moving the display image to the adjacent pixel and repeatedly performing the operation of capturing the display image N + 1 times, the data of all the pixels of the flat display device is captured.

  In S4, the image data of the display image is extracted from the image data captured by N + 1 times of imaging. The captured image data may not match the pixel position information of each pixel of the display image, but the address of each pixel information of the captured image is obtained based on the position of the previously captured marker. Integrate the data for each display pixel to obtain the data for each display pixel, and perform interpolation arrangement processing on the pixel density of the display image based on the address to determine the pixel information of each pixel of the display pixel Are interpolated to form one combined total display surface image from N + 1 pieces of display arrangement data.

Next, in S5, a correction coefficient for each pixel is calculated based on the reference luminance information set from the combined total display surface image data.
In S6, the calculated correction coefficient is read into the correction coefficient memory.
In step S7, the input R, G, B video signal is calculated by the luminance distribution calculation circuit based on the correction coefficient stored in the correction coefficient memory to correct the luminance information of the video signal.

Next, in S8, the video signal whose luminance distribution is corrected is developed in the video signal frame memory, and in S9, the luminance distribution corrected image is transmitted to the flat display device to display the image.
The luminance unevenness of the pixels is improved by the correction up to the above S9, but in order to further improve the uniformity of the luminance distribution of the display image, the corrected image is captured again and the processing steps from S2 are repeated. As a result, errors in the correction process can be reduced.

Further, according to the method of capturing an image displayed intermittently as described above, it is possible to measure the luminance of the entire display surface with the number of times of capturing one more than the number of pixels existing in the display pixel interval. Have.
Instead of such an imaging method, pixels in one column in the vertical or horizontal direction may be sequentially displayed, and images may be sequentially captured by moving the imaging unit in synchronization with the displayed pixels.

FIG. 4 is a diagram for explaining a method for sequentially displaying and imaging pixels on the display surface.
FIG. 4 shows a state in which the vertical display pixels 41 of the flat display device 1 are displayed, and the moving imaging means 42 is arranged in the vicinity of the display surface so that the display pixels can be imaged. it can.
When the imaging of the display pixel 41 is finished, the display pixel sequentially moves to adjacent pixels. Corresponding to the movement of the display pixel 41, the moving imaging means 42 also moves the display pixels while sequentially moving to measure the luminance of all the pixels of the flat display device. The obtained measurement data is shown in FIG. Processing is performed in the same manner as shown, and one composite whole display screen image is formed by arranging according to the address of each pixel information.
A line sensor camera or the like can be used as the moving image pickup means.

FIG. 5 is a diagram for explaining an example of the relationship between the pixel position and the imaging data in the adjustment method according to the present invention.
The example shown in FIG. 5A is a diagram for explaining an example of light output of a display pixel in which horizontal pixel positions are intermittently displayed at intervals of N = 6 pixels, and light output is performed every six pixels as shown on the vertical axis. Is observed.
FIG. 5B is a diagram for describing imaging data of the image shown in FIG. The imaging data indicates an imaging output having a spread centering on each display pixel, and greatly spreads in addition to the imaging output of the center display pixel at the horizontal pixel position.
In the adjustment method of the present invention, the imaging output spread by the intermittent display pixels that are displayed adjacent to each other is integrated using the imaging output in which the output of the adjacent display pixels does not affect the measurement result of the display pixels as a threshold value. Thus, by using the imaging output of one display pixel, it is possible to accurately measure the display pixel displayed intermittently.

FIG. 5C is a diagram for explaining the relative output of each display pixel obtained by one-time pixel display and imaging obtained by integration of the imaging output.
FIG. 5D is an example showing all the relative outputs of the imaging output obtained by the display and imaging of the display pixel N + 1 times, that is, 7 times.
FIG. 5E shows an example of the frequency distribution with respect to the relative output of the flat display device thus obtained. By adjusting the brightness of each display pixel based on the reference brightness, it is possible to accurately measure and correct the brightness of substantially all the pixels.

  In the above description, the method of imaging the display pixels by displaying the vertical pixel columns and sequentially moving in the horizontal direction has been described. However, the horizontal pixel columns are sequentially moved in the vertical direction. An image may be captured, and both measurement of the vertical pixel column and horizontal pixel column and pixel adjustment based on the measurement may be combined.

In general, when a display pixel in which a large number of pixels are arranged like a unit flat display element is imaged by an image sensor having a small pixel interval, moire fringes are generated due to the interference between the two. For example, in the case where 50 pixels on the image sensor side of the camera are associated with 64 pixels in the horizontal direction of the unit flat display element, luminance fluctuation due to moire fringes is observed in the captured image.
When moiré fringes are formed in the captured image, it becomes impossible to perform adjustment with high accuracy.

Therefore, the image sensor is moved slightly in the horizontal direction in order to remove the value of periodicity caused by blurring of the focus or interference between the display system and the imaging system, and reduction is performed by adding the imaging data captured for each movement. be able to.
In the above description, the case where the ratio of the pixel pitch between the image display system and the image capturing system is not so large has been described. Can be removed.
Hereinafter, the present invention will be described with reference to examples and comparative examples.

A total of 80 unit flat display elements formed of 64 pixels × 64 pixels × R, G, B pixels are arranged in a vertical direction of 8 and 10 in the horizontal direction, and the total number of pixels is 640 × 512 × R, G. , B flat display device is manufactured, the marker arranged around is lit, the marker is imaged by an imaging means having a CCD image sensor of 640 × 480 × R, G, B, and the address of the display image is set .
Next, the display surface was imaged at the same magnification as when the marker was imaged and displayed in a line in the vertical direction every 8 pixels.

Next, the display surface was imaged in the same manner by moving the column of display pixels to adjacent pixels. All of the display pixels were imaged by moving the display pixels that were intermittently displayed and the operation of imaging 9 times.
Based on the measured imaging data of each display pixel, data for each column of the display pixel was created, and then the data was arranged according to the address of the display pixel to create a composite display surface image.

FIG. 6 shows the luminance change of the formed composite display surface from the first pixel to the 32nd pixel. FIG. 6A shows the pixel change on the composite display surface, and FIG. 6B shows an enlarged view of the luminance change in the region from the 16th pixel to the 18th pixel indicated by A in FIG. 6A. Thus, the 16th and 18th pixels are slightly lower in luminance than the 15th and 19th pixels, and the 17th pixel is larger in brightness than the 16th and 18th pixels. Was a decrease.
After correcting the luminance of each pixel according to the procedure shown in FIG. 3 on the basis of the luminance change of the composite display surface, the luminance change is performed in the same manner as the case of creating the composite display surface by measuring the luminance of the display surface first. The measurement results are shown in FIG. The luminance change between the 16th pixel and the 18th pixel having a large luminance change could be corrected to the same luminance level as the other pixels.

Comparative Example 1
FIG. 7 shows changes in luminance from the first pixel to the thirty-second pixel when all pixels are displayed and the entire display surface is photographed and the luminance of all display surfaces is measured in the first embodiment. FIG. 7A shows a luminance change before correction, and FIG. 7B shows an enlarged view of a region indicated by B from the 16th pixel to the 18th pixel in FIG. 7A.
The luminance of the sixteenth pixel is reduced stepwise compared to the fifteenth pixel, the luminance of the seventeenth pixel is further reduced, and the luminance of the eighteenth pixel is reduced stepwise compared to the nineteenth pixel. It was.

Based on the luminance measurement results as described above, the luminance was measured in the same manner as in Example 1. As shown in FIG. 7C, the luminance changes from the 16th pixel to the 18th pixel. The change in brightness could not be corrected sufficiently. In imaging, the 16th and 18th pixels are lower than the actual luminance, and the 17th pixel is measured higher.
In Example 1 and Comparative Example 1, the corrected luminance was measured by measuring the luminance for each pixel with a color luminance meter (Topcon BM-7).

  According to the present invention, in a large-sized image display device in which a large number of unit flat display elements are arranged, information on each pixel of the image display device can be accurately measured without being affected by adjacent pixels. Since the composed composite display image can be adjusted by comparing it with the reference pixels, it is possible to adjust the image with high accuracy. Therefore, even in a large flat display device in which a large number of unit flat display elements are arranged, high-precision luminance correction is possible. Therefore, the present invention is extremely useful in industry that contributes to improving the quality of display images of a large flat display device.

FIG. 1 is a diagram illustrating a flat display device of the present invention. FIG. 2 is a diagram illustrating a flat display device of the present invention. FIG. 3 is a diagram for explaining the luminance adjustment procedure of the pixel of the flat display device of the present invention. FIG. 4 is a diagram for explaining a method for sequentially displaying and imaging pixels on the display surface. FIG. 5 is a diagram for explaining an example of the relationship between the pixel position and the imaging data in the adjustment method according to the present invention. FIG. 6 is a diagram illustrating the luminance change of the pixels on the composite display surface according to the embodiment. FIG. 7 is a diagram for explaining the luminance change of the pixels on the composite display surface of the comparative example.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Flat panel display device, 3 ... Plasma display element, 5,5-1, 5-n ... Unit plane display element, 7 ... Marker, 9 ... Display image, 11 ... Imaging means, 13 ... Captured image information, 15 ... Luminance distribution correction coefficient processing circuit, 17 ... correction coefficient memory, 19 ... video input signal, 21 ... gamma correction circuit, 23 ... luminance correction arithmetic circuit, 25 ... video signal frame memory, 27 ... display data array conversion processing circuit, DESCRIPTION OF SYMBOLS 29 ... Display data transmission circuit, 31 ... Display control circuit, 33 ... Address drive circuit, 35 ... Scan drive circuit, 37 ... Sustain drive circuit, 39 ... Power supply, 41 ... Display pixel, 42 ... Moving imaging means, 101 ... Planar type Display device, 102, 102A, 102B ... unit flat display element, 103 ... R pixel, 104 ... G pixel, 105 ... B pixel, 106 ... display pixel, a ... interval between display pixels, b ... unit The spacing between the surface display device

Claims (8)

In the adjustment method of the flat display device, after the entire display surface is imaged as an intermittent display at equal intervals in a line in the vertical or horizontal direction, the operation of sequentially moving the display pixels to the adjacent pixels is performed. After capturing all the pixels on the display surface once more than the number of pixels between the intermittent display pixels, the obtained imaging data is arranged based on the pixel arrangement information, and the combined total display surface image data is obtained. The pixel reference setting value is set from the created and arranged pixel information, the obtained setting value is compared with the arranged pixel information, the correction coefficient of each pixel is calculated, and the correction coefficient is stored in the correction coefficient memory. An adjustment method for a flat display device, wherein a video signal supplied to each pixel of the flat display device is adjusted by a correction coefficient called from a correction coefficient memory. 2. The method of adjusting a flat display device according to claim 1, wherein the number of pixels between adjacent display pixels is set to a size that allows the brightness of adjacent pixels displayed simultaneously to be measured. 3. The display pixel measuring means comprises a plurality of light measurement pixels arranged, and the measurement data from the plurality of light measurement pixels is integrated into display pixel data. The adjustment method of the flat-type display apparatus of description. 4. The process from the image pickup by the image pickup means to the adjustment by the video signal adjustment means is repeated after the video signal is adjusted by the correction coefficient called from the correction coefficient memory. Adjustment method of flat display device. The image data of each intermittent display pixel is captured by reducing the moire by shifting the focus from the in-focus position within a range in which the intermittently displayed adjacent images are separately captured when capturing the intermittently displayed image. 5. A method for adjusting a flat display device according to any one of 1 to 4. At least one of before and after the adjustment of the flat display device, the entire surface of the flat display device is displayed and the entire display surface is imaged, and the obtained imaging data is arranged based on the pixel arrangement information, Compare with the pixel reference value, calculate the correction coefficient of each pixel, store the correction coefficient in the correction coefficient memory, and adjust the video signal supplied to each pixel of the flat panel display device using the correction coefficient called from the correction coefficient memory 6. The method for adjusting a flat display device according to claim 1, wherein the adjustment method is performed after the operation. 7. The planar type according to claim 6, wherein the image capturing process is repeated a plurality of times while shifting the moire phase of the display image of the entire display surface image data, and the obtained image data is summed and averaged to obtain measurement data. Adjustment method of display device. In the adjustment method of the flat display device, an image pickup means that can move in the vertical or horizontal direction on the display surface of the flat display device and can simultaneously image a horizontal or vertical row is installed, and the pixels on the display surface are Alternatively, the image data is moved and displayed one by one in the vertical direction, and the image data obtained based on the pixel arrangement information is obtained by repeating the movement and imaging of the imaging unit in synchronization with the displayed pixels and imaging all the display pixels. To create composite total display surface image data, set the pixel reference setting value from the arranged pixel information, compare the obtained setting value with the arranged pixel information, calculate the correction coefficient of each pixel and correct An adjustment method for a flat display device, wherein the coefficient is stored in a correction coefficient memory, and a video signal supplied to each pixel of the flat display device is adjusted by a correction coefficient called from the correction coefficient memory.

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