JP2004069307A - Display inspection method and display inspection device for display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display inspection method and a display inspection device for a display panel for detecting a short circuit between upper and lower column electrodes separated from each other. <P>SOLUTION: When the display of the display panel is inspected, one of upper and lower divisional screens is caused to emit light in monochrome, and the other divisional screen remaining as a nonluminous screen is detected by an image sensor 2. Based on output video signals of the sensor 2, bright lines in the column direction are detected corresponding to display cell columns in the other divisional screen. When the bright lines are detected, an electrode short circuit is determined to have occurred between divided column electrodes corresponding to the cell columns from which the bright lines are detected. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a display panel display inspection method and the like for inspecting an electrode short between electrodes of a display panel in which display cells are arranged in a matrix.
[0002]
[Prior art]
A display panel comprising a plurality of row electrodes and a column electrode arranged in a direction orthogonal to the plurality of row electrodes, and a display panel having R, G, and B display cells formed at intersections of the row electrodes and the column electrodes. Are known. In such a display panel, when detecting a short circuit between adjacent electrodes, a single color pattern (R, G, B pattern) is displayed on the entire display panel. In this case, if there is a short circuit between the adjacent electrodes, the display cells of other colors emit light, so that a short circuit between the electrodes can be detected.
[0003]
[Problems to be solved by the invention]
Among the above display panels, there is a type in which column electrodes are divided in the vertical direction of the display panel. In such a type of display panel, as shown in FIG. 1, if the column electrodes in the vertically divided column electrode groups 101 and 102 are short-circuited to each other, a line defect that prevents normal display occurs. . However, when the above-described detection method for displaying a single color pattern on the entire display panel is adopted, a short circuit between the upper and lower column electrodes does not affect the display. Therefore, a short circuit between the upper and lower column electrodes cannot be detected.
[0004]
SUMMARY OF THE INVENTION It is an object of the present invention to provide a display inspection method and a display inspection device for a display panel that can detect a short circuit between upper and lower column electrodes provided separately from each other.
[0005]
[Means for Solving the Problems]
The display inspection method for a display panel according to claim 1, wherein a plurality of row electrodes, and a plurality of column electrodes arranged in a direction orthogonal to the plurality of row electrodes and forming a display cell at an intersection with the row electrodes, Wherein each of the column electrodes is divided in the display area in the column direction, and a line defect between the divided column electrodes of the display panel configured to allow simultaneous selection of display cells in row units on the divided screen is inspected. A display inspection method for a display panel, wherein one of the upper and lower split screens emits a single color light, the other split screen to be a non-light emitting screen is detected by an image sensor, and based on the output video signal, A bright line in the column direction corresponding to the display cell row in the other divided screen is detected, and an electrode short circuit occurs between the divided column electrodes corresponding to the display cell row where the bright line is detected. And judging a.
[0006]
The display inspection method for a display panel according to claim 2, further comprising a plurality of row electrodes and a plurality of column electrodes arranged in a direction orthogonal to the plurality of row electrodes and forming a display cell at an intersection with the row electrodes. One pixel is composed of display cells of three different emission colors arranged in the row direction and display cells of the same emission color are arranged in the column direction, and each of the column electrodes is divided in the display area in the column direction. A display panel inspection method for inspecting a line defect between divided column electrodes of a display panel configured to allow simultaneous selection of display cells in row units in a divided screen, wherein: Only the cell of one emission color in one split screen emits light, the other split screen which becomes a non-emission screen is detected by the image sensor, and based on the output video signal, the other split screen in the other split screen is displayed. Detecting the bright lines in the column direction corresponding to the shown cell columns, light lines are characterized by determined that the electrodes short circuit occurs between the divided column electrodes corresponding to display cell column was detected.
[0007]
The display inspection device for a display panel according to claim 3, wherein a plurality of row electrodes and a plurality of column electrodes arranged in a direction orthogonal to the plurality of row electrodes and forming a display cell at an intersection with the row electrodes, Wherein each of the column electrodes is divided in the display area in the column direction, and a line defect between the divided column electrodes of the display panel configured to allow simultaneous selection of display cells in row units on the divided screen is inspected. A display inspection apparatus for a display panel, comprising: a light emitting unit for emitting one color of one of the upper and lower split screens in a single color; an image sensor for detecting the other split screen to be a non-light emitting screen; and an output from the image sensor. A bright line in the column direction corresponding to the display cell column in the other divided screen is detected based on the video signal to be divided, and the divided line corresponding to the display cell column in which the bright line is detected is detected. A determination unit shall electrode short circuit occurs between the column electrodes, characterized in that it comprises a.
[0008]
The display inspection device for a display panel according to claim 4, further comprising a plurality of row electrodes and a plurality of column electrodes arranged in a direction orthogonal to the plurality of row electrodes and forming a display cell at an intersection of the row electrodes. One pixel is composed of display cells of three different emission colors arranged in the row direction and display cells of the same emission color are arranged in the column direction, and each of the column electrodes is divided in the display area in the column direction. A display panel inspection apparatus for inspecting a line defect between divided column electrodes of a display panel configured to be capable of simultaneously selecting display cells on a row basis in a divided screen, wherein: A light emitting means for emitting light of only one light emitting color cell in one split screen, an image sensor for detecting the other split screen to be a non-light emitting screen, and a video output from the image sensor Signal, a bright line in the column direction corresponding to the display cell column in the other divided screen is detected, and an electrode short circuit occurs between the divided column electrodes corresponding to the display cell column in which the bright line is detected. Determining means for determining that the operation has been performed.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of a display inspection method for a display panel according to the present invention will be described with reference to FIGS.
[0010]
FIG. 2 is a block diagram showing a configuration of an inspection apparatus used for a display inspection method of a plasma display panel, and FIG. 3 is a diagram showing an electrode arrangement and the like of a plasma display panel 30 to be inspected.
[0011]
As shown in FIG. 2, the inspection apparatus 100 includes an inspection machine main body 1 for turning on a plasma display panel 30 at the time of inspection, a CCD camera 2 for photographing a display surface of the plasma display panel 30, and a video signal from the CCD camera 2. And a control device 4 for controlling the image processing device 3, the CCD camera 2, and the image processing device 3. The image processing device 3 includes an image processing unit 3a that performs image processing for analyzing a light emission pattern described later, an image processing memory 3b that stores image data from the CCD camera 2 for each of RGB, and data to be subjected to image processing. Is provided with an image processing target memory 3c for temporarily storing
[0012]
As shown in FIG. 3, the tester main body 1 is provided with address drivers 11a and 11b, X sustain drivers 12a and 12b, and Y sustain drivers 13a and 13b connected to the electrodes of the plasma display panel 30.
[0013]
As shown in FIG. 3, the plasma display panel 30 is vertically divided into two parts, and the electrodes in each area are separated from each other. As shown in FIG. 3, in the upper divided area of the plasma display panel 30, column electrodes D1r, D1g, D1b, D2r, D2g, D2b... Dmr, Dmg, Dmb, row electrodes X1 to Xi, and rows The electrodes Y1 to Yi are provided. The column electrodes D1r to Dmb are connected to the address driver 11a, the row electrodes X1 to Xi are connected to the X sustain driver 12a, and the row electrodes Y1 to Yi are connected to the Y sustain driver 13a.
[0014]
In the lower divided area of the plasma display panel 30, column electrodes DA1r, DA1g, DA1b, DA2r, DA2g, DA2b... DAmr, DAmg, DAmb, row electrodes Xi + 1 to Xn, and row electrodes Yi + 1 to Yn. And are provided. The column electrodes DA1r to DAmb are connected to the address driver 11b, the row electrodes Xi + 1 to Xn are connected to the X sustain driver 12b, and the row electrodes Yi + 1 to Yn are connected to the Y sustain driver 13b.
[0015]
As shown in FIG. 3, each column electrode is sequentially assigned so as to repeatedly correspond to an R cell, a G cell, and a B cell, and in a display area 31, intersections with row electrodes X1 to Xn and row electrodes Y1 to Yn. An R cell, a G cell, and a B cell are formed for each. As shown in FIG. 3, one pixel is formed using a set of R cells, G cells, and B cells that are continuously arranged. An area 37 outside the display area is provided outside the display area 31.
[0016]
As shown in FIG. 3, the row electrodes X1 to Xn and the row electrodes Y1 to Yn are alternately arranged in a comb shape so as to extend from opposite sides. In addition, one row electrode X1 to Xn and one row electrode Y1 to Yn are assigned to one display cell row, and the row electrodes X1 to Xn and the row electrodes Y1 to Yn face in parallel in one cell. Placed.
[0017]
The column electrodes D1r to Dmb and the column electrodes DA1r to DAmb are vertically separated from each other at an intermediate portion of the display area 31. The arrangement of the column electrodes will be further described later.
[0018]
Next, a driving method of the plasma display panel 30 will be described.
[0019]
One field as a period for driving the plasma display panel 30 includes a plurality of subfields SF1 to SFN. As shown in FIG. 4, each subfield is provided with an address period for selecting a cell to be lit and a sustain period for keeping the cell selected in the address period lit for a predetermined time. Further, a reset period for resetting the lighting state in the previous field is further provided at the head of SF1, which is the first subfield. In this reset period, all cells are reset to lighting cells (cells on which wall charges are formed) or off cells (cells on which no wall charges are formed). In the former case, a predetermined cell is switched to a non-lighted cell in a subsequent address period, and in the latter case, a predetermined cell is switched to a lit cell in a subsequent address period. The sustain period is gradually increased in the order of the subfields SF1 to SFN, and a predetermined gradation display is enabled by changing the number of the subfields to be continuously turned on.
[0020]
In the address period of each subfield shown in FIG. 5, address scanning is performed for each line. That is, at the same time when the scanning pulse is applied to the row electrode Y1 constituting the first line, the column electrodes D1r, D1g, D1b, D2r... Dmb correspond to the address data corresponding to the cells of the first line. The data pulse DP1 is applied, and then the scan pulse is applied to the row electrode Y2 forming the second line, and at the same time, the data pulse DP2 corresponding to the address data corresponding to the second cell is applied to the column electrodes Z1 to Zm. Is applied. Similarly, the scanning pulse and the data pulse are simultaneously applied to the third and subsequent lines. Finally, at the same time as the scanning pulse is applied to the row electrodes Yn forming the n-th line, the column electrodes D1r, D1g, D1b, D2r,... Dmb respond to the address data corresponding to the cells of the n-th line. The applied data pulse DPn is applied. As described above, in the address period, a predetermined cell is switched from a lit cell to a non-lit cell or from a non-lit cell to a lit cell.
[0021]
When the address scanning is completed in this way, all the cells in the subfield are set as either the lighted cells or the lighted cells, and only the lighted cells emit light each time a sustain pulse is applied in the next sustain period. repeat. As shown in FIG. 5, during the sustain period, an X sustain pulse and a Y sustain pulse are repeatedly applied to the row electrodes X1 to Xn and the row electrodes Y1 to Yn at predetermined timings. In the last subfield SFN, there is provided an erasing period in which all cells are set to non-lighted cells.
[0022]
By repeating the above-described fields, gradation display in a moving image by the plasma display panel 30 becomes possible.
[0023]
Next, a procedure for inspecting a short circuit between column electrodes of the plasma display panel 30 using the inspection apparatus 100 will be described.
[0024]
As shown in FIG. 2, at the time of inspection, the plasma display panel 30 is set on the inspection apparatus main body 1, and one of the upper or lower divided regions in the display area 31 of the plasma display panel 30 is entirely monochrome. (For example, R color). At this time, black display is performed so that the entire other divided region does not emit light.
[0025]
FIG. 6 shows a light emission pattern and the like according to the presence or absence of a short circuit between column electrodes. FIG. 6A shows a case where there is no short circuit between the column electrodes, and the entire upper divided region 32 of the display region 31 emits monochromatic light. At this time, there is no cell that emits light in the lower divided region 33. The pattern shown in FIG. 6A is a detection pattern itself for detecting a short circuit between column electrodes. FIG. 6B shows a light emission pattern when there is a short circuit between column electrodes. FIG. 6C is a diagram showing a short-circuit portion between the column electrodes, in which the column electrodes in the column electrode group 101 provided in the upper divided region and the column electrodes 102 in the column electrode group 102 provided in the lower divided region. The short-circuit portion 103 in which the column electrodes of FIG. When there is such a short between the column electrodes, as shown in FIG. 6B, the column electrode provided in the upper divided region 32 via the short portion 103 and the column electrode provided in the lower divided region 33 are provided. Column electrodes are connected to each other. Then, a cell on a line (bright line) 104 along the column electrode in the column electrode 102 connected to the column electrode in the column electrode 101 emits light. For this reason, it is possible to detect a short circuit between the column electrodes.
[0026]
Such a light emission pattern of the plasma display 30 is captured by the CCD camera 2, and the image processing device 3 analyzes the light emission pattern based on the image data from the CCD camera 2.
[0027]
FIG. 7 is a flowchart showing a process at the time of inspection. 7 is executed based on the control of the control device 4.
[0028]
In step S1 of FIG. 7, the inspection machine main body 1 gives a driving pulse for causing the plasma display panel 30 to display the detection pattern. Thereby, the plasma display panel 30 is turned on in a light emitting pattern as shown in FIG. 6A or FIG. 6B, for example. The value of the flag indicating the presence / absence of a short point is initialized to a value indicating “no short point”. Next, the image of the light emission pattern is captured by the CCD camera 2 (step S2), and the image data of the captured image is transferred from the CCD camera 2 to the image processing memory 3b of the image processing device 3 (step S3). Here, RGB three-color data is transferred to separate memory areas.
[0029]
Next, a memory area in which the emission color (R, G, B) to be subjected to the image processing, that is, the data to be subjected to the image processing is set (step S4). Next, an approximate straight line approximating the center division line is calculated based on the image data stored in the image processing memory 3b (step S5).
[0030]
Next, of the image data stored in the image processing memory 3b, the entire one of the upper and lower divided areas that does not emit light is set as an image processing area (step S4). Here, the image processing area can be set based on the approximate straight line calculated in the process of step S5. In step S4, for example, when the detection pattern is the pattern shown in FIG. 6A, an area including the entire lower divided area 33 that does not emit light and the central divided line is set as an image processing area. Set.
[0031]
Next, based on the image data stored in the image processing target memory 3c, a process of extracting a bright point or a bright line in the image processing area is performed (step S7). Here, a bright point or a bright line is extracted for the luminescent color set in step S4. For example, in the case of the light emission pattern shown in FIG. 6B, a bright point or a bright line is extracted on the line 104 which is a bright line. In the case of the light emission pattern shown in FIG. 6A, no bright spot or bright line is extracted.
[0032]
Next, in step S8, it is determined whether or not a bright point or a bright line has been extracted in the process of step S7. If the determination is affirmative, the process proceeds to step S9, and if the determination is negative, the process proceeds to step S10. In step S9, assuming that there is a short-circuit between the column electrodes, the value of the flag indicating the presence or absence of the short-circuited portion is set to a value indicating "there is a short-circuited portion" for the corresponding emission color, and the process proceeds to step S11. On the other hand, in step S10, it is determined that there is a short circuit between the column electrodes, and the process proceeds to step S11 without changing the value of the flag indicating the presence or absence of the short circuit for the corresponding luminescent color.
[0033]
In step S11, it is determined whether or not the processing after step S1 has been completed for all the R, G, and B luminescent colors. If the determination is negative, the process returns to step S1 to return to the next luminescent color (for example, G color). Then, if the judgment is affirmative, the processing of FIG. 7 is terminated. As described above, after the processes of steps S1 to S10 are performed for each of the emission colors (R, G, B), all the processes are terminated.
[0034]
Through the above processing, the presence or absence of the column electrode is detected for each of the colors R, G, and B. The presence or absence of a column electrode can be determined for each emission color (R, G, B) based on the flag described above.
[0035]
As described above, in the display inspection method of the display panel of the present embodiment, only one of the divided areas of the display panel divided into upper and lower parts emits light, and the cells that emit light in the other divided area are extracted. A short circuit between the column electrodes can be reliably detected.
[0036]
In the above embodiment, an example of inspecting a color display panel in which cells of three luminescent colors are arranged has been described. However, the display inspection method of a display panel according to the present invention is suitable for inspecting a monochrome display panel in which monochromatic cells are arranged. Is also applicable. In this case, one of the cells in the divided region may emit light, and it may be detected whether or not the cells in the other divided region emit light.
[0037]
Further, in the above embodiment, the inspection of the plasma display panel has been exemplified, but the display inspection method of the display panel according to the present invention can be widely applied to other display panels.
[Brief description of the drawings]
FIG. 1 is a diagram showing a conventional inspection method.
FIG. 2 is a block diagram showing a configuration of an inspection apparatus used for a display inspection method of a plasma display panel.
FIG. 3 is a diagram showing an electrode arrangement and the like of a plasma display panel to be inspected.
FIG. 4 is a diagram showing a configuration of a field.
FIG. 5 is a timing chart showing driving pulses.
6A and 6B are diagrams showing light emission patterns and the like according to the presence or absence of a short between column electrodes, wherein FIG. 6A shows a case where there is no short between column electrodes, and FIG. 6B shows a case where there is a short between column electrodes. FIG. 3C is a diagram illustrating a light emitting pattern, and FIG. 3C illustrates a short portion between column electrodes.
FIG. 7 is a flowchart showing processing at the time of inspection.
[Explanation of symbols]
1 Inspection machine body (light emitting means)
2 Image sensor (CCD camera)
3 Image processing device (judgment means)
D1r, D1g to Dmb column electrode DA1r, DA1g to DAmb column electrode

Claims (4)

A plurality of row electrodes, and a plurality of column electrodes arranged in a direction orthogonal to the plurality of row electrodes to form display cells at intersections with the row electrodes, wherein each of the column electrodes has a column direction in a display area. A display inspection method of a display panel for inspecting a line defect between divided column electrodes of a display panel configured to be capable of simultaneously selecting display cells in row units on a divided screen,
One of the upper and lower split screens emits a single color light, the other split screen which becomes a non-light emitting screen is detected by an image sensor, and a display cell row in the other split screen is detected based on an output video signal. Detecting a bright line in a column direction corresponding to the display cell row, and determining that an electrode short-circuit has occurred between the divided column electrodes corresponding to the display cell row in which the bright line has been detected. Method. A plurality of row electrodes; and a plurality of column electrodes arranged in a direction orthogonal to the plurality of row electrodes and forming a display cell at an intersection with the row electrodes. The cells constitute one pixel and display cells of the same emission color are arranged side by side in the column direction. Each of the column electrodes is divided in the column direction in the display area. A method of inspecting a display panel for inspecting a line defect between divided column electrodes of a display panel configured to be possible,
Only one luminescent color cell in one of the upper and lower split screens emits light, the other split screen to be a non-light emitting screen is detected by an image sensor, and based on the output video signal, the other split screen is used. Detecting a bright line in the column direction corresponding to the display cell row in the divided screen of the divided screen, and determining that an electrode short circuit has occurred between the divided column electrodes corresponding to the display cell row in which the bright line has been detected. Characteristic display inspection method of display panel. A plurality of row electrodes, and a plurality of column electrodes arranged in a direction orthogonal to the plurality of row electrodes to form display cells at intersections with the row electrodes, wherein each of the column electrodes has a column direction in a display area. A display inspection apparatus for a display panel for inspecting a line defect between the divided column electrodes of a display panel configured to be capable of simultaneously selecting display cells in row units on a divided screen,
A light-emitting unit for emitting one color of one of the upper and lower divided screens,
An image sensor that detects the other split screen that is a non-light-emitting screen;
Based on the video signal output from the image sensor, a bright line in the column direction corresponding to the display cell row in the other divided screen is detected, and the bright line is divided corresponding to the detected display cell row. Determining means for determining that an electrode short has occurred between the column electrodes;
A display inspection apparatus for a display panel, comprising: A plurality of row electrodes; and a plurality of column electrodes arranged in a direction orthogonal to the plurality of row electrodes and forming a display cell at an intersection with the row electrodes. The cells constitute one pixel and display cells of the same emission color are arranged side by side in the column direction. Each of the column electrodes is divided in the column direction in the display area. A display panel inspection apparatus for inspecting a line defect between divided column electrodes of a display panel configured to be capable of,
A light emitting unit that emits light only in a cell of one luminescent color in one of the upper and lower split screens;
An image sensor that detects the other split screen that is a non-light-emitting screen;
Based on the video signal output from the image sensor, a bright line in the column direction corresponding to the display cell row in the other divided screen is detected, and the bright line is divided corresponding to the detected display cell row. Determining means for determining that an electrode short has occurred between the column electrodes;
A display inspection apparatus for a display panel, comprising:

Images