JP3375763B2 - Inspection method and apparatus for flat display device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a liquid crystal display device (hereinafter referred to as
LCD, cathode ray tube (hereinafter, CRT), plasma display, light emitting diode (hereinafter, LED), and the like. Each of the display screens of a flat display device having pixels in a matrix, such as a display device provided in a matrix. The present invention relates to an inspection method and an inspection device for a flat-panel display device that inspects display characteristics such as luminance of pixels.

[0002]

2. Description of the Related Art In recent years, the number of pixels has increased and the wiring pattern has tended to become thinner in response to the demand for larger display screens such as LCDs and higher definition. As a result, pixels which do not blink or whose brightness is lowered are apt to occur, and thus a flat-panel display device with defective display is likely to occur. Therefore, the inspection for checking the presence or absence of this kind of defect is important for the quality control of the final product and the quality control of the manufacturing process.

Conventionally, an LCD having pixels in a matrix
As a device for inspecting the brightness of each pixel of a flat-panel display device such as a CRT or the like, for example, as disclosed in Japanese Utility Model Laid-Open No. 4-55535, the same pitch as the interval between pixels in each row of the display device is used. There is disclosed a device for inspecting each pixel in each column of the display device by a line sensor having light receiving elements arranged in one column, and sequentially moving the line sensor to the next column to inspect all pixels.

Further, Japanese Patent Laid-Open No. 188950/1987 discloses an inspection panel in which a photodiode or the like is provided in a matrix at a pitch equal to or similar to a pixel pitch of a display device to be inspected and a switching element is provided. There is disclosed an apparatus for inspecting by using each pixel in association with each pixel of the display apparatus.

That is, in these inspection apparatuses, the luminance of each pixel is detected and stored once, and then the standard luminance data and the detected luminance data are compared, and the difference between the standard luminance data and a certain value or more is found. A pixel is determined to be defective. Therefore, the detected data is detected and stored in association with which pixel.

In the case of a large display screen such as a flat panel display device, the inspection is performed by moving the sensor or the display device in parallel and reading the entire screen. Also in this case, each detection element of the sensor is associated with each pixel of the display device. In an example in which a charge-coupled device (hereinafter referred to as CCD) camera is used as a sensor, an image of a display device formed on the light receiving surface of the CCD sensor is imaged and the above correspondence is performed. Generally a two-dimensional CCD
When using a camera, make the correspondence between the row direction of the pixels of the display device and the row direction of each detection element of the sensor, or the column direction of the pixel of the display device and the column direction of each detection element of the sensor. There is. Therefore, when the sensor or the display device is moved, it is moved in parallel in the row direction or the column direction for each pixel pitch to detect the luminance of each pixel while maintaining the relative positional relationship between the sensor and the display device.

As another method, the display screen of the display device may be divided into a plurality of display area groups, and the brightness may be detected by some CCD cameras. In this case, the above-mentioned correspondence fixes the relative positional relationship between the display screen and the sensor camera, and can recognize which pixel on the display screen is the coordinate from the pixel size of the display device. The display device and the sensor are associated with each other.

In the display screen inspection method described above, the size of each detection element of the sensor is made smaller than the pixel size of the display device, and the brightness of the same pixel is detected by a plurality of sensor elements. The accuracy of the luminance measurement is improved by assigning a plurality of sensing elements of the sensor to one pixel of the display device. As described above, the brightness value of each pixel of the display device detected by this method is temporarily stored, and the difference between the brightness value of the standard pixel is stored in the storage operation device such as a computer to determine the difference in brightness value set in advance. If it is larger, it is determined as a defective pixel. In this way, LC
To inspect the display characteristics of a flat panel display device such as a D or CRT, the display device or a sensor is moved from end to end of the display screen (hereinafter referred to as an inspection scan) to detect the brightness of all pixels of the display device. Then, it is stored once, and then compared with the standard brightness value of the display device, and if the difference in brightness is larger than a preset value, the display device is determined to be defective.

[0009]

In the device for detecting the brightness of each pixel while associating each pixel with the sensing element as described above, the accuracy of the measured brightness value determines the quality of the display device to be inspected. Therefore, the accuracy of the measured luminance is important. As a method of improving the measurement accuracy, one of the display devices is
There are a method of increasing the number of detecting elements of the sensor that can be assigned to one pixel and a method of repeating the luminance measurement several times. However, the number of sensing elements is limited by the pixel size of the display device and cannot be increased so much. In addition, the method of repeating the number of times of measurement is such that one measurement detects and stores the brightness of all the pixels once as described above, and then makes a comparison by comparing with the reference data one by one. There are problems that the processing speed of the process becomes slow and that the measurement time becomes long due to the large display screen.

On the other hand, in the case of a color display device, the brightness differs for each color of the color pixel of the display device, an inspection display screen is required for each color, and an inspection scan for each display screen of a different color is required. There is a problem that the process time is longer than that when inspecting a monochrome display device.

SUMMARY OF THE INVENTION An object of the present invention is to solve the conventional problems described above, and to provide an inspection method and an inspection apparatus which can improve the accuracy of luminance detection without increasing the number of times of luminance measurement.

Another object of the present invention is to provide a white screen display in which, in the case of a color display device, the brightness of three different colors of red, green and blue are simultaneously detected, and red, green and blue pixels are simultaneously developed. By inspecting, reduce the number of scanning of the display screen,
It is to shorten the time of the inspection process.

[0013]

A method of inspecting a flat panel display device according to the present invention is an inspection method for determining pass / fail of display characteristics of each pixel of a display screen of a flat panel display device having pixels in a matrix. A sensor for detecting the brightness of a partial area of the display screen detects the brightness of each pixel in the partial area, and vibrates the sensor in the row direction or the column direction of the matrix of pixels, The brightness of pixels in a part adjacent to the pixels in the partial area is also detected, and then the brightness detection of the pixels in the display screen is similarly repeated while sequentially scanning the area adjacent to the partial area.

It is preferable that the vibration amplitude of the sensor is an integral multiple of the pixel pitch of the display screen because the brightness of a plurality of pixels can be accurately detected by the vibration.

The display screen is a display screen in which red, green, and blue color filters are regularly provided in each pixel, and the amplitude of the vibration is (3m + 1) times the size of one pixel (m is 0).
Or a positive integer), the luminance sum S ₁ of the pixels detected by one reciprocation of the vibration is obtained, and then the luminance sum S ₂ of the pixels similarly detected by moving one pixel is obtained, and S ₁ −S ₂ Relative comparison of the luminances of pixels of the same color depending on the size is preferable because it is possible to relatively compare the luminances of adjacent pixels of the same color even in the case of a color display screen.

When the flat display device is a color display device, the three pixels of red, green and blue of the display screen in which red, green and blue color filters are regularly provided in each pixel are described above. It is possible to inspect three pixels at a time by detecting as one unit by the vibration of the sensor and inspecting the brightness of the combined white display of the three pixels.

After detecting the brightness by vibrating the sensor, the brightness is repeatedly detected while moving the sensor by three pixels when detecting the next row or column. Even in the case of a color display screen, the monochrome is detected. This is preferable because the inspection can be performed with the same number of scans as.

Further, the size of the sensing element for detecting the brightness of each pixel of the sensor is 1 / n (n
It is preferable to use a sensor having a size of 2 or more) to detect the brightness of one pixel with n detection elements, because the inspection accuracy can be improved.

The inspection device for a flat-panel display device of the present invention is an inspection device for illuminating the display screen of a flat-panel display device having pixels in a matrix and determining whether the display characteristics of each pixel on the display screen are good or bad. On the display screen, and
A stage that is movable at least in a plane, a sensor that is provided above the stage and that detects the brightness of a partial area of the display screen, and a vibration that vibrates the sensor in the row direction or the column direction of the matrix of pixels. Means and scanning means for scanning the sensor in the row and / or column direction of the pixels.

The sensor is composed of an array of detection elements for detecting light, and it is preferable that a plurality of detection elements for detecting one of the pixels are provided in order to improve inspection accuracy.

[0021]

According to the inspection method of the present invention, the sensor is vibrated while detecting the brightness of a partial area of the display screen.
For example, if a partial region consists of a row of 1 pixel, and if the vibration amplitude is vibrated in the direction perpendicular to the row of the partial region (scanning direction) by 1 pixel, a tripled area can be detected at once, One pixel can be inspected three times while moving once, and the inspection accuracy is improved. Further, if the amplitude of vibration is adjusted to the pitch of 2 pixels, a 5 times region can be detected at one time by one cycle of vibration, and inspection can be performed 5 times per pixel by moving the sensor camera once.

Further, the vibration cycle can be performed in about ten and several milliseconds even if the mechanical vibration of the camera itself is taken into consideration, and the camera is moved from one end of the display screen to the other to restore the original brightness. It is possible to easily perform the inspection three times or more per pixel in a shorter time than the increase in the number of times of repeating the detection, and the inspection accuracy is significantly improved.

Furthermore, since the brightness of adjacent pixels is detected by the detection element of the same camera, the difference in brightness value between adjacent pixels can be detected, and the detected data of the entire display screen is temporarily stored. Then, without comparing with the reference data after that, it is possible to relatively judge the quality of the brightness of each pixel only by storing the detected data in one line in the scanning direction, and the inspection time can be shortened. it can.

If the amplitude of the vibration is an integral multiple of the pixel pitch, the brightness of each pixel can be always detected, and the inspection accuracy can be improved.

Even in the case of a color display screen, R, G,
It is vibrated so that an integral multiple of 3 pixels of B is one reciprocation of vibration, and the luminance sum at that time is obtained, and the sensor is moved by one pixel to obtain the luminance sum in the same manner. How much the difference is greater than 0 By checking that, it is possible to comparatively inspect adjacent luminances of pixels of the same color.

Further, when the display device is in color, the adjacent pixels repeat red, green and blue. Therefore, when the brightness is detected by each pixel alone, the brightness is different for each of the red, green and blue single colors and the mutual comparison is performed. It is difficult to judge pass / fail by using, but by inspecting the brightness of 3 pixels as one set, white display or gray display of 3 pixel simultaneous display can be made, comparison inspection becomes very easy, and scanning is performed every 3 pixels. Thus, even if the number of pixels increases in color display, the inspection process time can be the same as in monochrome.

If the size of the detecting element of the sensor is 1 / n of the size of each pixel on the display screen, one pixel can be detected by n detecting elements, and the inspection accuracy is improved by n times. Become.

According to the inspection apparatus of the present invention, since the vibrating means for vibrating the sensor for detecting the luminance of a part of the display screen is provided, the sensor is vibrated and the neck is vibrated after one row of scanning is completed. It is possible to further swing and scan, and as described above, the inspection accuracy can be improved and the inspection time can be shortened.

If there are a plurality of detecting elements of the sensor for each pixel, one pixel can be inspected by a plurality of detecting elements within one scanning period, so that the inspection accuracy is improved.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An inspection apparatus and an inspection method for a flat panel display device according to the present invention will be described below with reference to the drawings.

[Embodiment 1] FIG. 1 is a conceptual diagram of an embodiment of the inspection apparatus of the present invention. In FIG. 1, reference numeral 1 denotes a stage on which an LCD 3 which is a display device is mounted, and the x direction and the y direction (one direction in the plane and the direction orthogonal to the one direction in the same plane) and the θ direction (in the xy plane). It is equipped with a 3-axis motor that can be moved in the direction of rotation. The camera 2 detects the mark 3a provided on the LCD 3 in order to adjust the stage 1 so that the LCD 3 is placed on the stage 1 for inspection and the positional relationship with the sensor camera 4 is constant. , An LCD having pixels in a matrix in the y direction and having the mark 3a, and a plurality of 2
A sensor camera having a dimension detection element, the sensor camera 4
The scanning direction of is the y direction in this embodiment. Reference numeral 5 is a motor for vibrating the sensor camera 4 and moving the sensor camera 4 for the inspection scan. Reference numeral 6 is used to compare the brightness signal obtained by the sensor camera 4 and the brightness of the standard device stored in advance by arithmetic processing. Therefore, the computer for controlling the position (inspection scan) and vibration of the sensor camera 4 and for controlling the three-axis motor that moves the position of the stage 1 so as to keep the positional relationship between the LCD 3 and the sensor camera 4 constant. is there. The motor 5 and the computer 6 constitute a vibrating means and a scanning means. Reference numeral 7 is a drive circuit for driving the LCD 3 to be inspected, and 8 is an arm capable of vibrating the sensor camera 4 in the x direction in this embodiment.

In this device, the LCD 3 is placed on the stage 1, the sensor camera 4 and the LCD 3 are aligned with each other by the mark 3a, the backlight (not shown) is turned on, and the LCD 3 is driven by the drive circuit 7 to detect the sensor. The camera 4 detects the brightness of each pixel. In this embodiment, in order to detect the luminance, the sensor camera 4 is vibrated with an amplitude of one pixel in a direction (x direction) orthogonal to the scanning direction (y direction), and the display screen is moved from one end to the other in the y direction. Scan,
The luminance of pixels in one column in the scanning direction is detected and one inspection scan is performed. After completing this one inspection scan, the sensor camera 4
Is shaken to swing the head, and scanning is further performed in the y direction from end to end, and the sensor camera 4 is returned by the vibration, and the adjacent adjacent column is scanned again in the y direction from end to end. Next, the sensor camera 4 is moved by one pixel in the x direction and similarly inspected, this inspection scan is performed on the entire screen, and the brightness values of the pixels obtained by the inspection scan are relatively compared for each column, or The computer 6 compares the brightness of each pixel of the standard device to determine the quality of the flat panel display device.

In this embodiment, the amplitude of the vibration of the sensor camera 4 is set as the pitch interval (width of the pixel size) of the pixels on the display screen, so that the brightness of the pixels adjacent to both sides can be measured, and the brightness of the pixels adjacent to each other can be measured. The pixels to be checked are again inspected by the movement of the sensor camera 4, and eventually one pixel is detected three times, which improves the detection accuracy of the square root multiple of three. If the half cycle T / 2 of vibration is about twice (2t) the brightness detection time t of all pixels of the sensor in the scanning direction (usually about 0.5 ms for CCD or photodiode), there is no problem in brightness detection. Therefore, it is possible to detect three pixels while saving the time for moving the sensor camera 4.

Next, a method of detecting the brightness of the adjacent pixels while actually vibrating the sensor will be described. FIG. 3 shows an example of the positional relationship between the pixels of the conventional inspection apparatus and the detection element of the sensor, and shows a cross section along the x direction of FIG. In this description, for simplification, the size of the sensor is set to a size for measuring one pixel on the display screen. Figure 3
In (a), 9 indicates a pixel group along the x direction, and 1
0 is the detection element of the sensor camera, 11 is the i-th red (hereinafter, R) pixel Ri, and 12 is the i-th green (hereinafter, R).
Pixels Gi and 13 (referred to as G) indicate the i-th blue (hereinafter referred to as B) pixel Bi, respectively. In addition, the size of the pixel is W, the size of the sensing element is W _s , and the brightness detection time of the sensor is t. The sensor camera is moved in the inspection scan direction (the direction perpendicular to the paper surface of the pixel group 9 shown in FIG. 3A in the y direction) to detect the luminance of all pixels on the display screen, and the x direction shown in FIG. The graph of FIG. 3B plots the brightness of each pixel of the pixel group arranged in line. In the graph of FIG. 3B, the solid line indicates the measured data, the broken line indicates the reference data, and if the difference between the broken line and the solid line data is a certain value or more, the pixel is treated as defective. FIG. 2 is a diagram for explaining the inspection method of the present invention, in which the detection element 10 and the pixel group 9 of the sensor camera are used.
3A is the same as that in FIG. 3A, and the reference numerals are the same as those in FIG. 3A.

In the present invention, as shown in FIG. 2, the sensor camera 4 is vibrated and scanned in the x direction with an amplitude having the same width as the width W of the pixel. Therefore, after the row of Gi pixels 12 is inspected in the y direction, the Ri pixel 11 and the Bi pixel 13 are detected in the same manner, and then the sensor camera is moved in the x direction (for example, on the Bi pixel 13). Is similarly detected. The half cycle of this vibration requires the detection time of the Gi pixel 12 and the detection time of the Ri pixel 11, and as described above, it is necessary to detect the luminance in the one pixel direction (all the same color pixels in the y direction). If the time is t, 2t hours are necessary. As shown by the broken line in FIG. 3B, the brightness of the standard device also differs depending on R, G, and B, so each data must be compared with each standard value. However, by vibrating as in the present invention, three adjacent R, G, and B pixels can be continuously detected, and therefore, it is possible to compare only pixels of the same color by moving a normal sensor camera, and No change in brightness.

More specifically, referring to FIG. 2, the brightness of the pixels Ri, Gi, Bi is measured by scanning on the pixel Gi. In the next scan on the pixel Bi,
The brightness of the pixels Gi, Bi, Ri + 1 is measured. Further, in the next scan on the pixel Ri + 1, the pixels Bi and Ri +
The luminance of 1 and Gi + 1 will be measured. Assuming that the brightness sum of the scans at each position is S1, S2, and S3, the brightness difference between S1 and S2 means that the brightness between Ri and Ri + 1 is compared. The brightness difference between S2 and S3 is Gi and Gi.
This means that the brightness difference with +1 is being compared. By performing this processing, it is possible to compare the brightness of R, G and B of the same color.

In the present embodiment, the vibration direction of the sensor camera is the vertical direction (x direction) with respect to the scanning direction (y direction), but the same applies when vibrating in the same direction as the scanning direction. Further, the detection element of the sensor is not limited to one pixel, but may be a sensor that detects a range in which partial areas of a plurality of pixels are combined. For example, in the above-described embodiment, a sensor for detecting one line in the entire x-direction performs scanning in the y-direction while vibrating in the y-direction to perform inspection, and thus the entire display screen is detected a plurality of times per pixel in one inspection scan. Can be inspected at.

[Second Embodiment] In the first embodiment, the vibration amplitude of the sensor camera 4 is matched with the size of the pixel on the display screen.
Although the amplitude is set to 1, the amplitude is an integral multiple of the pixel size (m
By setting m to 2 or more, the number of pixels that can be detected without moving the sensor camera is (2m + 1), and the luminance inspection accuracy is the square root times (2m + 1) when the sensor is not vibrated.

When the sum of the luminances of the pixels during one round trip of vibration is calculated on the color display screen and the difference from the sum of the luminances after the movement of the sensor is calculated, R, G, B and three colors are set as a set. Since it needs to be detected, it can be used by setting the amplitude of vibration to (3m + 1) times the size of one pixel (m is 0 or a positive integer).

When a CCD sensor is used as the sensor, the detection time is about several tens of milliseconds even when m is 5, which is very small compared with several hundreds of milliseconds between pitch movements during scanning. The inspection time is almost never longer than when it is not vibrated. From this point of view, the larger m is, the better the luminance detection accuracy is, which is preferable. However, since the sensor camera 4 is actually vibrated, the distance between the sensor and the pixel to be detected is changed when m is large, and the luminance detection pixel is changed. On the other hand, since the brightness is detected obliquely, it is preferable to set the brightness to about 10.

[Third Embodiment] In the first embodiment, in the color display device, even if the R, G and B pixels are regularly arranged, the brightness of each of the R, G and B pixels is detected at once. For example, the R pixel and the G pixel are compared and detected, but in the present embodiment, they are detected as the brightness of white display in which three colors of R, G, and B are combined. By doing this, the sum of the three pixels should originally have the same color and the same brightness,
The pass / fail judgment can be detected by mutual comparison of only the detected luminance values, and the pass / fail judgment can be made without storing the detection data in advance and comparing with the standard data. As a result, data processing is simplified and scanning can be performed in units of 3 pixels, so that the inspection time can be further shortened. Further, if the sensor camera is moved pixel by pixel, it is the same as measuring the same pixel three times, and the detection accuracy is improved.

[Fourth Embodiment] In the first embodiment, each detecting element of the sensor camera is formed by one detecting element corresponding to one pixel of the display screen. However, the detecting element is 1 / n (n is 2 or more). integer)
By reducing the size to n and making each pixel n sensing elements, one pixel is detected by n sensing elements, and the square root multiple luminance detection accuracy of n is improved. To do. Therefore, when vibrating with an amplitude m times the size of the pixel in the second embodiment, one pixel is detected by (2m + 1) · n detection elements, and the luminance detection accuracy is (2
It is dramatically improved by multiplying the square root by m + 1) · n.

In each of the above embodiments, the LC is used as the display device.
Although D is used, the same inspection can be performed on a flat panel display device having pixels in a matrix such as a CRT other than LCD, a plasma display, a display device using a light emitting diode.

Furthermore, according to the present invention, it corresponds to performing inspection a plurality of times per pixel in any case,
Since the inspection accuracy is greatly improved, if the only purpose is to judge the quality of the display device, the brightness value of the detected pixel can be set to the peripheral value without having to associate each pixel of the display device with the detection element of the sensor. The inspection can be performed only by comparing with the luminance value of the pixel and without comparing with the luminance value of the standard device. However, when specifying a defective pixel, the defective pixel can be specified by associating with the coordinates of each pixel as in the conventional case.

[0045]

According to the inspection method of the present invention, since the sensor camera is scanned while vibrating, the inspection is performed while detecting one pixel a plurality of times, and the accuracy of detecting the brightness of each pixel is improved. To do. Therefore, the quality of the display device can be determined without storing the detected data and comparing it with the standard data, and the inspection process is simplified.

Further, the inspection accuracy can be efficiently improved by multiplying the amplitude of the vibration by an integer (m) times the pixel size of the display screen, and the inspection accuracy can be further improved by increasing m. it can.

In the case of a color display screen, set the vibration amplitude to 1
The brightness sum of the pixels due to one reciprocating vibration is calculated as (3m + 1) times (m is 0 or a positive integer) of the pixel, and the brightness of the adjacent pixels of the same color is mutually calculated by calculating the difference between the brightness sums adjacent to each other. They can be compared and easily inspected on a color display screen.

Further, when inspecting the brightness of each pixel of the color display device, the brightness of each color of R, G, B is checked by inspecting the pixels of R, G, B, and three colors together as a white display. It is not necessary to consider the difference between, and the inspection can be performed more easily.

Further, since the inspection can be performed with R, G, B, and 3 pixels as one unit, the inspection time can be shortened by moving the sensor by 3 pixels, and a monochrome display screen can be obtained. You can do the inspection at the same time.

Further, by setting the size of each detecting element of the sensor to 1 / n of the size of each pixel of the display screen and detecting by n detecting elements per pixel, the luminance detection accuracy can be further improved. , The reliability of inspection increases.

According to the inspection apparatus of the present invention, since the vibrating means for vibrating the sensor is provided, it is possible to inspect a plurality of pixels in a single inspection step and improve the inspection accuracy. This is further improved by using a plurality of detecting elements of the sensor per pixel.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of an embodiment of an inspection device of the present invention.

FIG. 2 is a diagram illustrating a positional relationship between a sensing element and a pixel of a display device for explaining an embodiment of an inspection method of the present invention.

FIG. 3 is a diagram illustrating a positional relationship similar to FIG. 2 of a conventional inspection method.

[Explanation of symbols]

1 stage, 3 LCD, 4 sensor camera, 5 motors, 6 computer, 10 detection elements, 11 R pixels, 12 G pixels, 13 B pixels.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuki Inoue Address: 997 Miyoshi, Miyoshi, Nishigoshi-machi, Kikuchi-gun, Kumamoto Prefecture (56) References JP-A-4-301684 (JP, A) JP-A-6- 58839 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G01M 11/00-11/08 G01N 21/84-21/958 G02F 1/13

Claims (8)

(57) [Claims] 1. A method for inspecting whether or not the display characteristics of each pixel of a display screen of a flat-panel display device having pixels in a matrix form are good or bad, and a sensor for detecting the brightness of a partial area of the display screen is used. The brightness of each pixel in the partial area is detected, the sensor is vibrated in the row direction or the column direction of the matrix-shaped pixels, and the brightness of the pixel in a portion adjacent to the pixel in the partial area is also detected. Then, a method for inspecting a flat panel display device, in which the brightness detection of the pixels of the display screen is similarly repeated while sequentially scanning the area adjacent to the partial area. 2. The inspection method according to claim 1, wherein the vibration amplitude of the sensor is an integral multiple of the pixel pitch of the display screen. 3. The display screen is a display screen in which red, green, and blue color filters are regularly provided in each pixel, and the amplitude of the vibration is (3m + 1) times the size of one pixel (m is 0). Or a positive integer), the luminance sum S ₁ of the pixels detected by one reciprocation of the vibration is obtained, and then the luminance sum S ₂ of the pixels similarly detected by moving one pixel is obtained, and S ₁ −S ₂ The inspection method according to claim 2, wherein luminances of pixels of the same color are relatively compared according to size. 4. A red, green, and blue color filter, which is regularly provided in each pixel, detects three pixels of red, green, and blue on a display screen as one unit by the vibration of the sensor, and the three pixels are detected. The inspection method according to claim 1, wherein the inspection is performed as the brightness of the combined white display. 5. The inspection method according to claim 4, wherein after the sensor is vibrated to detect the luminance, the luminance is repeated while moving the sensor by three pixels when detecting the next row or column. 6. The size of the sensing element for detecting the brightness of each pixel of the sensor is 1 / n (n is 2) of the size of each pixel.
The inspection method according to claim 1, 2, 3, 4, or 5, wherein the brightness of one pixel is detected by n detection elements using a sensor having a size of the above integer). 7. An inspection apparatus for illuminating a display screen of a flat-panel display device having pixels in a matrix to determine whether display characteristics of each pixel of the display screen are good or bad, wherein the display screen is mounted. In addition, a stage that is movable at least in a plane, a sensor that is provided above the stage and that detects the brightness of a partial region of the display screen, and a sensor that vibrates in the row direction or the column direction of the matrix of pixels. An inspecting device for a flat-panel display device, comprising: a vibrating unit for causing the sensor to scan; 8. The inspection apparatus according to claim 7, wherein the sensor is composed of an array of detection elements for detecting light, and a plurality of detection elements for detecting one of the pixels are provided.