JP2005010641A - Device and method for adjusting flickering of display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device and a method for adjusting the flickering of an image display device that can precisely reflect variation in luminance on adjusting algorithm. <P>SOLUTION: A TFT-mounted product 2 is equipped with a TFT display 3 and a power source whose AC-converted driving voltage can be adjusted according to a control signal. A color pattern generator 4 supplies an image signal for white display to a plurality of pixels of the TFT display 3. A CCD camera 5 images the display screen with a plurality of pixels. The RGB output of the CCD camera 5 is stored in a frame memory 12 by pixels. A CPU 14 calculates quantities of variation in luminance by the pixels from variation in luminance stored in the frame memory 12 and supplies a control signal to the power source of the TFT-mounted product 2 so that the calculated quantity of variation in luminance decreases as to the plurality of pixels, thereby adjusting the AC-converted driving voltage. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a flicker adjustment apparatus and method for a display device such as a liquid crystal display device.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a liquid crystal display device such as a play compared with a TFT which is a TFT (Thin Film Transistor) active matrix type liquid crystal display device is driven by alternating current for the purpose of avoiding deterioration of the liquid crystal. The AC drive is performed by alternately inverting the polarity of the voltage applied to the pixels of the liquid crystal display device. If there is an offset or the like in the driving electronic circuit, the voltage applied to the liquid crystal changes depending on the polarity. The polarity inversion of alternating current is performed at every frame period for displaying an image for one screen. When the luminance changes at every polarity inversion, display flickering called flicker occurs. In a liquid crystal display device that performs alternating driving, flicker is unavoidable, and adjustment of the driving voltage is performed to reduce the flicker. This adjustment is usually performed so that flickering is reduced when the operator visually observes the screen.
[0003]
Devices that detect flicker with a sensor from a screen of a display device and automatically adjust the flicker to be small have also been proposed (see, for example, Patent Document 1, Patent Document 2, and Patent Document 3). A transmissive display device and an image processing device that receive light from a small area of a liquid crystal panel with an optical sensor and perform RGB luminance correction or chromaticity correction have also been proposed (for example, see Patent Document 4).
[0004]
In Patent Document 1, the transmitted light emitted from the liquid crystal display panel is condensed on the surface of the optical sensor by the condenser lens, the AC component of the detection signal is extracted, and the liquid crystal is set so that the PP value is minimized. A trimmer provided on the display panel is mechanically adjusted. In Cited Document 2, the optical system is adjusted so that the number of scanning lines of the liquid crystal display panel and the number of scanning lines of the image connected to the CCD camera coincide with each other, and a part or all of the display range is set as a measurement range, and is inverted and driven for each field In this case, the luminance is summed for each field in the measurement range, and it is determined that there is no flicker when the luminances of the respective fields coincide with each other, and D / A (Digital / Analog) conversion is performed so as to be in this state. Adjust the driving voltage, and adjust the volume and trimmer mechanically with the rotational driving force of a stepping motor or the like. In Patent Document 3, a voltage value difference that causes flicker specific to a liquid crystal panel is obtained in advance for each pixel and stored in a correction value storage circuit as a correction value. I'm trying to prevent it.
[0005]
[Patent Document 1]
JP-A-6-130920
[Patent Document 2]
Japanese Unexamined Patent Publication No. 7-98574
[Patent Document 3]
Japanese Patent Laid-Open No. 8-24062
[Patent Document 4]
JP 2001-265296 A
[0006]
[Problems to be solved by the invention]
In the conventional flicker adjustment of the TFT display, the point at which the flicker is minimized is adjusted by a trimmer while the operator looks at the screen. For this reason, there is a variation due to a difference in visual sense between workers, and there is a problem that the visual acuity and attention of the worker are lowered by continuing to see that it is flickering. However, in order to automate, it is necessary to identify the cause of “flicker” that humans feel, and to quantify the numerical value expressed in numerical values, and the quantitative value must match the visual value. Not established.
[0007]
In the methods disclosed in Patent Document 1 and Patent Document 2, the luminance for each field is summed, and the adjustment is made so as to minimize the luminance difference between the fields. In such a technique, the luminances in the field are simply summed up. If the total values are the same, it is impossible to distinguish between cases where the luminance values vary and are uniform. It may not be possible to adjust to reduce flicker due to the cause. In particular, in the vicinity of the adjustment point where the luminance difference between the fields is minimum, it is difficult to visually perceive the luminance difference between the fields as flickering. Instead, you will feel flickering brightness that flows randomly on the screen. The effect of such random luminance variations cannot be reflected in an algorithm for adjusting flicker by simply taking the luminance sum or average. In addition, when the screen brightness is detected by an imaging device including a plurality of picture elements, the brightness value may vary even if the sensitivity varies between the picture elements.
[0008]
An object of the present invention is to provide a flicker adjustment device and method for an image display device capable of accurately reflecting variations in luminance in an adjustment algorithm.
[0009]
[Means for Solving the Problems]
The present invention is an apparatus that adjusts flickering of a display device including a display that performs alternating drive and a power source that can adjust the alternating drive voltage according to a control signal,
Display control means for controlling a plurality of pixels constituting the display screen of the display to perform display by giving predetermined image signals of the same level;
Screen imaging means for imaging the display screen of the display unit with a plurality of picture elements;
For a plurality of picture elements constituting the video imaged by the screen imaging means, a memory for storing the brightness for each picture element;
A variation amount calculating means for calculating a variation amount of luminance for each pixel from a variation in luminance stored in the memory,
And a voltage adjusting unit that provides a control signal to the power supply of the display device and adjusts the alternating drive voltage so that the variation amount of luminance calculated by the variation amount calculating unit is reduced for a plurality of picture elements. This is a flicker adjustment device for the display device.
[0010]
According to the present invention, the flicker adjustment device for a display device is a display control device as a device that adjusts flicker of a display device including a display that performs alternating drive and a power source that can adjust the alternating drive voltage according to a control signal. Means, screen imaging means, memory, variation calculation means, and voltage adjustment means. The display control means performs control so that a plurality of pixels constituting the display screen of the display are given the same predetermined level, for example, an image signal for a white image, and display is performed. The screen imaging means images the screen of the display device with a plurality of picture elements, and the luminance for each picture element is stored in the memory. The fluctuation amount calculating means calculates the luminance fluctuation amount for each picture element from the luminance change stored in the memory, so that the flickering of the luminance of the pixel of the screen imaged by each picture element is close to a human sense. The amount of variation can be obtained. Since the voltage adjustment means gives a control signal to the power supply of the display device and adjusts the alternating drive voltage so that the fluctuation amount of luminance calculated by the fluctuation amount calculation means decreases for a plurality of picture elements, the variation in luminance Can be accurately reflected in the adjustment algorithm, and the AC drive voltage can be adjusted so that the flickering that humans feel is reduced.
[0011]
In the present invention, the fluctuation amount calculating means calculates a standard deviation as the fluctuation amount.
[0012]
According to the present invention, the fluctuation amount calculating means calculates the standard deviation as the luminance fluctuation amount for each picture element, so that it is possible to easily grasp statistical data variations.
[0013]
Further, in the present invention, the voltage adjusting unit calculates an average of the standard deviation of the luminance for the plurality of picture elements, and supplies the control signal to the power source of the display device so that the average is minimized. It is characterized by.
[0014]
According to the present invention, since the average of the standard deviation for each picture element is calculated, the flickering of the display screen can be grasped as the average. Since the AC drive voltage of the display is adjusted so that the average is minimized, the flicker recognized as the average can be adjusted to be minimized.
[0015]
Further, in the present invention, the voltage adjusting unit provides the control signal to the power source of the display device so that the maximum value among the standard deviations of the luminance is minimized for the plurality of picture elements. And
[0016]
According to the present invention, the flicker of the pixel having the maximum standard deviation should be most noticeable on each screen. If the alternating drive voltage of the display is adjusted, the pixel with the maximum standard deviation may be different. Even if the pixels are different, if the AC drive voltage is adjusted so that the standard deviation is the smallest for the pixel with the largest standard deviation and the largest flicker, the flicker can be adjusted to be the least noticeable on the entire screen. it can.
[0017]
Also, in the present invention, the voltage adjustment means sends the control signal to the display device so that an average of standard deviations regarding a predetermined portion is minimized on the side where the standard deviation of luminance is large for the plurality of picture elements. It is characterized by being fed to the power source of.
[0018]
According to the present invention, for a plurality of picture elements, a predetermined portion on the side where the standard deviation of luminance is large, for example, a half on the large side, should feel flicker greater than other portions. By adjusting the AC voltage, even if the pixels belonging to the side with the large standard deviation of brightness change, if you compare the average of the standard deviation of the part that feels flickering large and adjust the average to be the minimum, It is possible to minimize luminance variations that are easily perceived as flickering.
[0019]
In the invention, it is preferable that the screen imaging unit images the display screen with a larger number of picture elements than the plurality of pixels.
[0020]
According to the present invention, since the number of picture elements is larger than the number of pixels on the display screen, the luminance of one pixel on the display screen can be reflected on the luminance of one or more picture elements. Flickering can be detected with certainty and adjusted to reduce.
[0021]
Furthermore, the present invention provides a plurality of pixels constituting a display screen of a display device that performs alternating drive while giving a predetermined same level image signal to perform display.
Take an image of the display screen with multiple picture elements,
For a plurality of picture elements constituting an imaged image, the luminance fluctuation is calculated for each picture element, and the AC drive voltage of the display device is adjusted so that the luminance fluctuation for the plurality of picture elements is reduced. This is a flicker adjustment method for a display device characterized by the above.
[0022]
According to the present invention, the flicker adjustment of the display device is performed by giving a plurality of pixels constituting the display screen of the display device the same predetermined level, for example, an image signal for a white image and performing display. Since the screen is imaged with a plurality of picture elements and the fluctuation in luminance is obtained for each picture element, a fluctuation amount close to the human sense can be obtained with respect to the flickering of the screen. Since the control signal is supplied to the power supply of the display device and the AC drive voltage is adjusted so that the amount of variation in brightness decreases for multiple pixels, brightness variations can be accurately reflected in the adjustment algorithm. The AC drive voltage can be adjusted so that the flicker that is felt is reduced.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a schematic electrical configuration of a flicker adjustment device 1 for a display device according to an embodiment of the present invention. A TFT-mounted product 2 that is a display device to be adjusted includes a TFT display 3 that is a display that performs alternating drive, and a power source that can adjust the alternating drive voltage according to a control signal. The color pattern generator 4 functions as a display control unit that controls a plurality of pixels constituting the display screen of the TFT display 3 to give a predetermined same level, for example, an image signal for white display to perform display. . On the display screen of the TFT display 3, a plurality of pixels are selectively driven by a TFT active matrix method to form a display image. A CCD (Charge Coupled Device) camera 5 is disposed in front of the TFT display 3 and functions as a screen imaging unit that images a display screen with a plurality of picture elements. The CCD camera 5 receives the vertical synchronization signal VD sent from the color pattern generator 4 via the camera adapter 6 and captures a color image using the three primary color components of RGB in synchronization with the frame period of the display screen. Instead of the CCD camera 5, other types of screen imaging means such as a MOS image sensor can be used.
[0024]
The RGB output of the CCD camera 5 is input to the image acquisition board 11 of the personal computer 10. The image acquisition board 11 includes a frame memory 12 and can store image data for at least one frame for each picture element. If the RGB output from the CCD camera 5 is digitized, each luminance of RGB is stored in the frame memory 12. If the RGB output from the CCD camera 5 is an analog signal, the image acquisition board 11 is provided with an ADC (Analog Digital Converter) and stores the luminance value in the frame memory 12 after analog / digital conversion. The personal computer 10 is also provided with a DIO board 13, which inputs and outputs digital signals, gives a remote control signal to the color pattern generator 4, and controls a VIDEO OUT signal given to the TFT mounted product 2. With such control, not only flicker adjustment but also luminance adjustment and chromaticity adjustment can be performed.
[0025]
The personal computer 10 also includes a CPU 14 as a fluctuation amount calculating means for calculating a luminance fluctuation amount for each picture element from the luminance change stored in the frame memory 12. The CPU 14 calculates the amount of variation according to a program that is read in advance from a nonvolatile storage device such as a ROM or a hard disk, or a recording medium such as a CD-ROM or DVD-ROM, or downloaded by information communication, It also functions as a voltage adjusting means for supplying a control signal to the power source of the TFT mounted product 2 and adjusting the AC drive voltage so that the calculated luminance fluctuation amount is reduced for a plurality of picture elements. As the voltage adjusting means, communication control for the TFT-mounted product 2 is performed via the communication gateway 15 connected by a data transmission interface such as RS232C.
[0026]
FIG. 2 shows a schematic electrical configuration of the TFT mounted product 2. The overall control of the TFT-mounted product 2 is performed by the microcomputer 20. A communication circuit 21 is provided for a communication interface with the communication gateway 15 of FIG. The flicker adjustment of the TFT display 3 is performed by changing the voltage generated by the microcomputer 20 from the DAC (Digital Analog Converter) 22 according to the control data received by the communication circuit 21. The voltage generated from the DAC 22 is supplied to the power source 23 to adjust the offset voltage during AC driving. The power source 23 supplies power for operation to the entire TFT-equipped device 2.
[0027]
The image display by the TFT display 3 is performed by the drive circuit 24 driving each pixel AC. The period of the alternating signal is the period of the vertical synchronization signal included in the image signal from the color pattern generator 4 in FIG. Vertical synchronization is several tens of milliseconds, and image display is performed several tens of times per second. The microcomputer 20 stores control data to be set in the DAC 22 in the memory 25. The memory 25 is configured by a non-volatile ROM capable of writing data, such as a flash memory. During normal operation as the TFT-mounted product 2, control data read from the memory 25 is given to the DAC 22 in an initialization routine such as after power-on. A signal processing circuit 26 for obtaining an image to be displayed on the TFT display 3 is provided.
[0028]
FIG. 3 shows a procedure in which the CPU 14 of FIG. 1 calculates a standard deviation as a luminance variation amount for each picture element of the CCD camera 5. The procedure is started from step s0. In step s1, image data for performing white display, that is, display with the three primary colors of RGB each having the maximum luminance is given from the color pattern generator 4 to the TFT mounted product 2. In step s2, the TFT camera 3 is imaged by the CCD camera 5. In step s3, the luminance is stored in the frame memory 12 for each of the plurality of captured picture elements. The storage of the luminance for a plurality of picture elements is performed for different storage areas for each frame. In step s4, it is determined whether or not a predetermined number of frames, for example, 10 frames has been reached. If the predetermined number of frames has not been reached, the process returns to step s2, and the storage of the luminance for each picture element is repeated for the next frame. When it is determined in step s4 that the predetermined number of frames has been reached, in step s5, the luminance data stored for each frame in the frame memory 12 is read for each picture element, and the standard deviation is calculated. When the standard deviation is calculated for all the picture elements, the procedure ends at step s6.
[0029]
Since the CPU 14 as the fluctuation amount calculating means calculates the standard deviation as the luminance fluctuation amount for each picture element, it is possible to easily grasp the statistical data variation.
[0030]
FIG. 4 shows a procedure for adjusting the TFT display 3 so as to minimize the flicker. The procedure is started from step a0. In step a1, default control data is given to the DAC 22 to the TFT mounted product. In step a2, a default average value for the minimum value, for example, a maximum value that can be displayed with a digital signal having a predetermined number of bits, is stored in the memory reserved for calculating the minimum value. In step a3, the standard deviation is calculated according to the procedure shown in FIG. In step a4, an average value of standard deviations for each picture element is calculated. In step a5, the value stored in the memory for calculating the minimum value is compared with the calculated value as an average. If the calculated value is smaller, in step a6, the calculated value as an average is stored in the memory for calculating the minimum value. In step a7, the voltage of the DAC 22 is increased by a predetermined value, and the process returns to step a3. If the calculated value does not become smaller than the stored value in step a5, the process proceeds to step a8.
[0031]
In step a8, the voltage of the DAC 22 is decreased by a predetermined value. In step a9, the standard deviation is calculated according to the procedure shown in FIG. In step a10, the average value of the standard deviation for each picture element is calculated. In step a11, the value stored in the memory for calculating the minimum value is compared with the calculated value as an average. If the calculated value is smaller, the average calculated value is stored in the memory for calculating the minimum value in step a12, and the process returns to step a8. If the calculated value is not smaller than the stored value in step a11, the process proceeds to step a13. In step 13, the voltage of the DAC 22 is increased by a predetermined value. This is for returning to the state in which the calculated value is determined to be smaller than the stored value in step a11. The procedure ends at step a14.
[0032]
As described above, the CPU 14 as the voltage adjusting means calculates the average of the standard deviation of the luminance for the plurality of picture elements captured by the CCD camera 5, and sends the control signal to the TFT mounted product 2 so that the average becomes minimum. To 23 power supplies. Since the average of the standard deviation for each picture element is calculated, the flickering of the screen of the TFT display 3 can be grasped as an average. Since the alternating drive voltage of the TFT display 3 is adjusted so that the average is minimized, it is possible to adjust so that the flicker grasped as the average is minimized.
[0033]
FIG. 5 shows a procedure for adjusting the flicker by the flicker adjusting apparatus 1 of the display device of FIG. 1 as another embodiment of the present invention. Except step b2, step b4, step b5, step b6, step b10, step b11 and step b12, that is, step b0, step b1, step b3, step b7, step b8, step b9, step b13 and step b14 are This is equivalent to each step of step a0, step a1, step a3, step a7, step a8, step a9, step a13 and step a14 of FIG. In step b2, the default maximum value is stored in a memory area reserved for storing the minimum value. In step b4, the maximum value is selected from the standard deviations for each picture element. In step b5, the selected value is compared with the stored value. In step b6, the selected value is set as a new stored value. In step b10, as in step b4, the maximum value is selected from the standard deviations for each picture element. In step b11, the selection value and the stored value are compared as in step b5. In step b12, the selected value is set as a new stored value in the same manner as in step b6.
[0034]
That is, the CPU 14 as the voltage adjusting means selects the maximum value among the standard deviations of the luminance for the plurality of picture elements instead of calculating the average value in FIG. Thus, the control signal is supplied to the power source 23 of the TFT-equipped device 2. According to the human sense, the flickering of the pixel having the maximum standard deviation should be most noticeable on each screen. If the alternating drive voltage of the TFT display 3 is adjusted, the pixel having the maximum standard deviation may be different. Even if the pixels are different, if the AC drive voltage is adjusted so that the standard deviation is the smallest for the pixel with the largest standard deviation and the most noticeable flicker, the flicker can be adjusted to be the least noticeable on the entire screen. it can.
[0035]
FIG. 6 shows a procedure for adjusting the flicker by the flicker adjusting apparatus 1 of the display device of FIG. 1 as still another embodiment of the present invention. Steps c0 to c3, steps c5 to c9, and steps c11 to c14, excluding steps c4 and c10, are the same as steps a0 to a3, steps a5 to a9, and steps a11 to a14 in FIG. is there. In step c4 and step c10, instead of taking the average value of all the standard deviations of the plurality of picture elements in step a4 and step a10 of FIG. 4, the average value is taken for half of the large standard deviations.
[0036]
The CPU 14 that is a voltage adjusting means sends a control signal to the power supply of the TFT-mounted product 2 so that the average of the standard deviations regarding a predetermined portion such as a half on the side where the standard deviation of luminance is large is minimized. 23. For a plurality of picture elements, the half on the side where the standard deviation of the luminance is large should feel that the flicker is larger than the other parts. By adjusting the AC voltage, even if the pixels belonging to the side with the large standard deviation of brightness change, if you compare the average of the standard deviation of the part that feels flickering large and adjust the average to be the minimum, It is possible to minimize luminance variations that are easily perceived as flickering.
[0037]
4, 5, and 6, the predetermined value for increasing or decreasing the DAC voltage may be decreased stepwise to perform quick and high-precision adjustment such as coarse adjustment, intermediate adjustment, and fine adjustment. it can.
[0038]
FIG. 7 exaggerates an example of an image in which flickering is felt between display lines for convenience of explanation. FIG. 7 shows an odd field and an even field when there is a luminance difference between the lines, and the polarity is inverted between the fields by AC driving. When the DAC 22 is controlled by 8 bits, about 20 is set in hexadecimal.
[0039]
FIG. 8 shows an example of an image in which no flicker is felt between display lines. Although the polarity of AC drive is inverted between the odd field and the even field, no difference is felt. When the control of the DAC 22 is performed by 8 bits, about 83 is set in hexadecimal.
[0040]
In each embodiment, it is preferable to image the display screen of the CCD camera 5 and the TFT display 3 with a larger number of picture elements than the number of pixels constituting the display screen. Since the number of picture elements is larger than the number of pixels on the display screen, the brightness of one pixel on the display screen can be reflected in the brightness of one or more picture elements, and flicker within one display screen can be detected reliably. This is because it can be adjusted so as to reduce.
[0041]
Note that the luminance fluctuation for each picture element can be obtained by other values such as a fluctuation width which is a difference between the minimum value and the maximum value, without depending on the standard deviation. In addition, other types of liquid crystal display panels, such as simple matrix type liquid crystal display panels that are not TFT displays, electroluminescent (EL) panels, plasma display (PD) panels, and other display devices that perform AC drive Similar adjustments can be made to minimize flicker.
[0042]
【The invention's effect】
As described above, according to the present invention, the screen of the display device is imaged with a plurality of picture elements, and the amount of change in luminance is calculated for each picture element. A close variation amount can be obtained, and variations in luminance can be accurately reflected in the adjustment algorithm. Since the alternating drive voltage is adjusted so that the amount of variation in luminance is reduced for a plurality of picture elements, the alternating drive voltage can be adjusted so that the flicker felt by a person is reduced.
[0043]
Further, according to the present invention, since the standard deviation is taken as the luminance variation amount for each picture element, the luminance variation can be accurately reflected in the adjustment algorithm.
[0044]
According to the present invention, since the average of the standard deviation for each picture element is calculated, the flickering of the display screen is reflected as an average in the adjustment algorithm, and the average flickering is adjusted to be minimum. Can do.
[0045]
Further, according to the present invention, even if the pixels are different, the AC drive voltage is adjusted so that the standard deviation is the smallest for the pixel having the largest standard deviation and the most noticeable flicker, and the flicker is the least noticeable. can do.
[0046]
In addition, according to the present invention, it is possible to ignore other portions that deviate from a predetermined portion on the side where the standard deviation of luminance is larger, and to reflect the effect when flickering is visually observed in the adjustment algorithm.
[0047]
Further, according to the present invention, the luminance of one pixel on the display screen is reflected on the luminance of one or more picture elements, and flickers between pixels in one display screen are reliably detected and adjusted to reduce. be able to. Even if the luminance variation flickers randomly on the screen, it can be surely reduced.
[0048]
Furthermore, according to the present invention, the amount of variation in luminance that is close to the human sense of flickering on the screen while performing display by giving a predetermined same level of image signal to a plurality of pixels constituting the display screen of the display device. Thus, the variation in luminance can be accurately reflected in the adjustment algorithm, and the alternating drive voltage can be adjusted so that the flicker felt by a person is reduced.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a schematic electrical configuration of a flicker adjustment device 1 of a display device according to an embodiment of the present invention.
2 is a block diagram showing a schematic electrical configuration of the TFT-mounted product of FIG. 1;
3 is a flowchart showing a schematic procedure for calculating a standard deviation for each picture element captured by a CCD camera 5 in the flicker adjustment device 1 of the display device of FIG. 1;
FIG. 4 is a flowchart showing a procedure for adjusting flicker to a minimum in the embodiment of FIG. 1;
FIG. 5 is a flowchart showing a procedure for adjusting flicker to a minimum according to another embodiment of the present invention.
FIG. 6 is a flowchart showing a procedure for adjusting flicker to a minimum according to still another embodiment of the present invention.
FIG. 7 is a diagram illustrating an example of an image in which flicker occurs for each display line.
FIG. 8 is a diagram illustrating an example of an image without flicker.
[Explanation of symbols]
1 Display flicker adjustment device
2 Products with TFT
3 TFT display
4 Color pattern generator
5 CCD camera
10 PC
11 Image Income Board
12 frame memory
14 CPU
20 Microcomputer
22 DAC
23 Power supply
24 Drive circuit
25 memory

Claims (7)

A device that adjusts flickering of a display device including a display that performs alternating drive and a power source that can adjust the alternating drive voltage according to a control signal,
Display control means for controlling a plurality of pixels constituting the display screen of the display to perform display by giving predetermined image signals of the same level;
Screen imaging means for imaging the display screen of the display unit with a plurality of picture elements;
For a plurality of picture elements constituting the video imaged by the screen imaging means, a memory for storing the brightness for each picture element;
A variation amount calculating means for calculating a variation amount of luminance for each pixel from a variation in luminance stored in the memory,
And a voltage adjustment unit that provides a control signal to the power supply of the display device and adjusts the AC drive voltage so that the variation amount of luminance calculated by the variation amount calculation unit is reduced for a plurality of picture elements. Display flicker adjustment device. The flicker adjustment device for a display device according to claim 1, wherein the fluctuation amount calculation means calculates a standard deviation as the fluctuation amount. The voltage adjusting unit calculates an average of the standard deviation of the luminance for the plurality of picture elements, and supplies the control signal to a power source of the display device so that the average is minimized. Item 3. A flicker adjustment device for a display device according to Item 2. 3. The voltage adjusting unit supplies the control signal to a power source of the display device so that a maximum value among the standard deviations of the luminance is minimized for the plurality of picture elements. The flicker adjustment device of the display device described. The voltage adjusting means supplies the control signal to the power supply of the display device so that the average of the standard deviations regarding a predetermined portion is minimized on the side where the standard deviation of the luminance is large for the plurality of picture elements. The flicker adjustment device for a display device according to claim 2. The flicker adjustment apparatus for a display device according to claim 1, wherein the screen imaging unit images the display screen with a larger number of picture elements than the plurality of pixels. While giving a plurality of pixels constituting a display screen of a display device that performs AC driving to display a predetermined image signal of the same level,
Take an image of the display screen with multiple picture elements,
For a plurality of picture elements that make up the captured video, find the variation in brightness for each picture element,
A flicker adjustment method for a display device, characterized in that an AC drive voltage of the display device is adjusted so that a variation in luminance with respect to the plurality of picture elements is reduced.

Images