JPH1020836A - Display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To specify and detect a defective point by generating a cursor moving in pixel and generating and displaying the display positional information of the cursor. SOLUTION: A cursor signal generation part 7a generates a cursor signal according to inputted cursor transitive information, and a synthetic part 7b superimposes it onto the prescribed position of the video data. Further, a cursor positional information generation part 7c generates cursor positional information according to the cursor transitive information to output it, and the synthetic part 7d superimposes it onto the prescribed position of the video data. In such a manner, the cursor signal and cursor positional information generated in a cursor processing part 7 are superimposed onto the video data to be supplied to a liquid crystal column driver 8, and liquid crystal molecules are driven by a plasma driver 12, and the data are displayed on a screen. The cursor is moved to the defective point beforehand specified by observation, and a drive circuit (IC) and pin numbers, etc., of the drive circuit corresponding to the defective point are detected from the position of the cursor to be specified.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device using, for example, a plasma addressed liquid crystal display device for forming an image by, for example, an active matrix system.

[0002]

2. Description of the Related Art In recent years, in order to obtain more powerful images in consideration of, for example, an installation space that can be secured in a home, a large and thin television receiver, a rear projection type Projector devices have become widespread. These television receivers and rear projection type projector devices have been considerably thinner than those of the past in accordance with technological progress, but in the case of television receivers, for example, CRT (Cathode Ray Tube). depth,
Further, in the case of a projector device, there is a limit to a reduction in thickness due to structural conditions such as an angle at which a projection lens is installed.

A display device using a TFT (Thin Film Trangistor) liquid crystal panel can be made thinner than the above-mentioned television receiver and projector device. However, in order to make a large display device, it is formed by IC technology. As the number of TFTs increases, a more precise manufacturing technique is required, and the manufacturing yield is lowered, so that the manufacturing cost becomes extremely high. Therefore, a plasma-addressed liquid crystal display device (Plasma Addressed Liquid Cr) that forms a large screen equivalent to that of a television receiver or a projector device and realizes a thickness as thin as a liquid crystal display
A display device using ystal (hereinafter abbreviated as PALC) as a display unit has been considered. This plasma addressed liquid crystal display element utilizes the advantages of a TFT liquid crystal display device of high brightness and high contrast,
A large screen can be realized by the technology of P (Plasma Display Panel).

FIG. 10 is a diagram for explaining an outline of a PALC and a drive system of the PALC, for example. The PALC 20 has a large number of electrodes formed in the horizontal and vertical directions to drive each pixel in a matrix. If the PALC 20 performs color display of, for example, 640 pixels in the horizontal direction and 480 pixels in the vertical direction, 640 × 3 = 1920 drive electrodes are derived in the horizontal direction according to the pixels of each color of RGB, and 480 in the vertical direction. A number of plasma electrodes have been derived.
When a large-sized display device having a size of 20 inches or more is formed, these electrodes include, for example, a flexible type flat cable HFc (1920) and a flat cable VFc.
(480 columns), a liquid crystal column driver 40 and a plasma driver 50 in which a plurality of driving circuits are configured.
Is supplied. Note that, for example, 20
When a small-sized display device of inches or less is configured, the PALC 20, the liquid crystal column driver 40, and the plasma driver 50 are integrally configured in consideration of power consumption and manufacturing cost.

[0005] The liquid crystal column driver 40 includes a plurality of driving circuits 40a, 40b, 40, for example, composed of integrated circuits (ICs).
., 40d, 40e...
One line of pixel data input to the liquid crystal column driver 40 is divided and input to each of the drive circuits 40 (a to f...), And the generated drive signal is transmitted to the PALC 20 via the flat cable HFc. Are supplied to the drive electrodes of

The plasma driver 50 comprises a plurality of drive circuits 50a, 50b, 50c, 50d, etc., for example, formed of integrated circuits, like the liquid crystal column driver 40. Each of the driving circuits 50 (a to e) is configured to drive by dividing 480 scanning lines, and the driving circuits 50 a to 50 e correspond to the timing of scanning.
Are sequentially output from the terminals of... And supplied to the electrodes formed in the plasma channel of the PALC 20 described later. As a result, a plasma discharge is generated in the plasma channel, and the pixel can be driven in accordance with the drive signal supplied from the liquid crystal column driver 40.

FIG. 11 is a perspective view showing a part of the structure of the PALC 20, and a part thereof is shown in cross section. PAL
The C20 is structured as a transmissive display element that forms an image by selectively transmitting a light beam emitted from a backlight (not shown) disposed on the back surface thereof by an active matrix method.

On the plasma substrate 21, partition walls 22, 22,
22 form a scanning groove 23, 23, 23,..., Or a cut groove (not shown), which is partitioned into a hollow shape in the horizontal direction, for example. In the scanning grooves 23, the anodes 24, 2
, And cathodes 25, 25, 25,.
Are formed as a pair. That is, the scanning grooves 23 form horizontal scanning lines corresponding to the effective screen of the PALC 20, and are constituted by the number of scanning lines (for example, about 48). And these cathodes 25, 25, 2
5 ... A flat cable VFc derived from the plasma driver 50 is connected to each. By disposing a glass substrate 26 on which an insulating layer is formed in front of the partitions 22, 22, 22, the scanning grooves 23, 2,
Can be hermetically sealed, and the inside thereof is filled with a mixed rare gas such as helium gas as a plasma gas.

A scanning voltage of, for example, a negative pulse of about -300 V is applied to the cathode 25 from a plasma driver circuit (not shown), and the anode 24 and the cathode 25 are driven by the plasma pulse supplied at a predetermined timing. Plasma discharge is performed between them. By this plasma discharge, an electrical conductor (plasma channel) is formed in the scanning groove 23 until plasma particles ionized by the plasma gas are completely eliminated, and the same operation as the switching element is performed.

In front of the glass substrate 26, a liquid crystal display element 27 for forming pixels in a matrix, and striped filter sections 28G, 28B, 2 corresponding to RGB colors.
8R, a stripe-shaped drive electrode 29G, 29B, 2 for driving pixels of the liquid crystal display element 27.
The transparent electrode layer 29 made of 9R forms the scanning grooves 23, 23, 23.
Are formed so that this orthogonal portion becomes one pixel. Then, these drive electrodes 29G, 29
B, 29R,..., And a flat cable HFc derived from the liquid crystal column driver 40 is connected to each of the liquid crystals. That is, the drive electrodes 29G, 29
B, 29R,... Are supplied with video signals for one horizontal line, and the plasma gas in the scanning groove 23 is sequentially discharged in the vertical direction.
A video signal is applied to the liquid crystal of the pixel where (G, B, R) and the scanning groove 23 intersect, and the transmittance of light emitted from the backlight differs for each pixel, so that a color image can be displayed.

That is, as shown in FIG.
A polarization filter 30 on the incident side and the output side of
By arranging 31, the transmission amount of light polarized by the liquid crystal display element 27 can be controlled, and a color image can be obtained by the same principle as that of a normal TFT liquid crystal display device.

[0012]

When manufacturing such a large-sized flat display device, a display unit and a drive system (IC) are connected by a flat cable or the like via a connector. If there is a connection failure with the device, the pixel drive is not performed normally and the product becomes defective. In the case of a small-sized display device, the display unit and the drive system are integrally formed, so that it is difficult to repair and need to be replaced. However, as shown in FIG. 10, they are connected by a flexible type substrate or the like. With a large-sized display device, it is possible to repair a defective portion (such as disconnection).

In this case, a method for specifying a defective portion is as follows.
For example, it is conceivable that the defective portion is observed by visually observing the display unit, or that the defective portion is electrically contacted with the wiring pattern by using a measuring instrument such as an oscilloscope or a tester to detect.
However, since the size of one pixel is 1 mm or less, when observing a defective portion by visually observing the display section, it is difficult to accurately specify the defective portion, which is a very time-consuming operation. In addition, even when using a measuring instrument to make electrical contact with the wiring to detect a broken part, it is necessary to contact a fine signal line, which may cause secondary failure by contacting a nearby signal line. turn into. Further, the detection of a defective portion is not limited to the above-described PALC 20, but also has a similar problem in a normal liquid crystal display device or the like.

[0014]

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and a horizontal driver for supplying a video signal for each horizontal line to pixels arranged in a matrix is provided. And a vertical driver for selectively sequentially supplying a drive signal to the horizontal line. A display device that scans a screen with the horizontal driver and the vertical driver to form an image is displayed on a screen and input. Cursor generating means for generating a cursor that can be moved in pixel units according to the transition information, cursor position information generating means for generating and displaying display position information of the cursor, and converting the cursor and display position information into a video signal. The display device is provided with superimposing combining means.

According to the present invention, a cursor for detecting a defective portion is displayed, and the cursor is moved to the defective portion specified by observation in advance, so that the driving circuit ( IC), the pin number of the driving circuit, and the like can be detected and specified.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the display device according to the present invention will be described. FIG. 1 is a diagram showing a circuit block particularly for a video system of a display device in which the plasma addressed liquid crystal display element of the present embodiment is configured as a display unit. This plasma-addressed liquid crystal display device has the same structure as the PALC 20 described with reference to FIGS.

NTSC (National Television System C)
The signal is demodulated into a luminance signal and a color difference signal in a demodulator 1 and supplied to a double speed converter 2. In addition, the synchronization signal extracted here is supplied to a control unit 14 described later, and the control unit 14 generates an operation clock of each functional circuit described below to synchronize various signal processes. . A frame memory capable of storing one frame of video signal (luminance signal, color difference signal) is provided in the double speed conversion unit 2, and a motion component is detected by the frame memory. Then, in the still image area, the video signal of the current field and the video signal of one horizontal period one field before are read twice consecutively at twice the reading speed. In the moving image area, the video signal of one horizontal period of the field information at that time and the interpolated video signal generated by the interpolation processing using the video signals of one horizontal period above and below the same are read at double speed, and are read at 525H / 60Hz. Is converted to a non-interlaced signal.

The video signal that has been subjected to the double-speed processing is subjected to color adjustment, hue adjustment, and the like in the video signal processing unit 3, and then R, G, and B primary color signals are generated by inverse matrix processing. . Each of the primary color signals generated here is converted into digital video data V8b by an A / D converter 4 having an 8-bit quantization precision, and further equivalently converted by a frame rate conversion unit 5 into 8 bits. It is converted into 7-bit video data V7b having considerable accuracy. The video data V7b (R color, G color, B color) is supplied to the cursor processing unit 7 after being subjected to white balance processing by the white balance adjustment unit 6. As will be described later in detail with reference to FIG. 2, the cursor processing unit 7 generates a cursor displayed on the screen when detecting a defective portion of the PALC 20 and cursor position information, and supplies the cursor information from the white balance adjustment unit 6. It is superimposed on the video data to be output.

The liquid crystal column driver 8 has video data for one horizontal period (for example, 640 pixels), that is, 640 pixels ×
Pixels of three channels (R, G, B) (for example, 19
The video data V7b (20 pixels) is latched, and the video data V7b for each pixel is held for one horizontal period. The pixel data held here is read out for each horizontal line when a plasma discharge is generated in a predetermined scanning groove 23 by the plasma driver 12, and furthermore, the pixel data is read out.
/ A converter 9 converts the analog signals into
The voltage is applied to the drive electrodes 29R, 29G, and 29B of the LC 20.

The LCD controller 10 is configured to operate with a power supply of about 7 V, for example, and operates in accordance with an operation clock generated based on a synchronization signal to generate an S-shaped correction waveform generator 11.
Clock driving the plasma, and the plasma driver 1
2 is driven to generate a plasma pulse for plasma discharge for each scanning groove 23 (horizontal line). The count clock is supplied to the S-shaped correction waveform generation unit 11 to generate an S-shaped correction waveform for controlling the driving rate according to the transmittance characteristics of the liquid crystal molecules to be pixels. The S-shaped correction waveform is supplied to the liquid crystal column driver 8, and S-shaped correction (γ correction) is performed on the video data V7b that has been subjected to the white balance processing.

The plasma driver 12 sequentially selects the scanning grooves 23 formed in the PALC 20 and supplies a plasma pulse to the scanning grooves 23.
A plasma discharge is generated by a power supply voltage of V. That is, in synchronization with the double-speed video data V7b input to the liquid crystal column driver 8, the scanning grooves 23, 23, 23,... Are sequentially plasma-discharged from the top to the bottom, for example, and the discharge state is repeated for each field. The liquid crystal display element 27 can be driven according to the video data. As a result, the input video signal can be displayed as a video.

The backlight 13 is arranged as a light source for illuminating the PALC 20 from the back side, and a light beam emitted from the backlight 13 passes through predetermined pixels of the liquid crystal display element 27 to form a display image. Further, picture adjustment can be performed by adjusting the brightness of the light source.

The control unit 14 generates operation clocks for the above-described respective functional circuits from the input synchronization signal to synchronize various signal processings, and also transmits a signal from the remote commander RC to the light receiving unit 15.
In accordance with a command input through the controller, various kinds of control such as tuning of a tuner, image adjustment, and power on / off are performed. Further, in the present invention, when the display device is powered on while a specific key of the remote commander RC is pressed, a transition is made to a failure detection mode for displaying a cursor for detecting a defective portion such as disconnection between the PALC 20 and the drive system. You can do it.
Then, when a cursor movement command is input by the remote commander RC, cursor movement information is generated from this operation. In the defect detection mode, the cursor shift information, the vertical / horizontal synchronization pulse, and the operation clock are supplied to the cursor processing unit 7.

Next, the cursor processing unit 7 will be described in detail with reference to FIG. FIG. 2 is a diagram for explaining in detail a main part of the block diagram of FIG. 1 in order to explain the cursor processing unit 7. Note that the NTSC demodulator 1, double speed processor 2, video signal processor 3, A / D converter 4, frame rate converter 5, and white balance adjuster 6 shown in FIG. ing.

First, the liquid crystal column driver 8 and the plasma driver 12 will be described in detail. The liquid crystal column driver 8 includes, for example, a plurality of drive circuits 8 formed of an integrated circuit (IC).
a, 8b, 8c, 8d, 8e, 8f, etc. For example, 32 pins are led out from each of the driving circuits 8a, 8b, 8c,..., And for example, the 108th (3 × 32 + 12 = 108) from the horizontal scanning start point is the twelfth pin of the third driving circuit 8c. It can be said that it is a pin. In other words, if it is possible to determine the line in the horizontal direction from the horizontal scanning start point, the drive circuit and the pin number of the drive circuit can be specified. One line of pixel data input to the liquid crystal column driver 8 is divided and input to the drive circuits 8 (a to f...), And the generated drive signals are transmitted to the PALC 20 via the flat cable HFc. It will be supplied to the drive electrode. It is assumed that the D / A converter 9 is also included in the liquid crystal column driver 8 shown in FIG.

The plasma driver 12 includes a plurality of driving circuits 12a, 12b, 12c,
12d... Each of the driving circuits 12a, 12b, 12c,... Has, for example, 32 pins led out, and if it is possible to determine the number of the horizontal line, a driving circuit that drives that horizontal line;
And the pin number of the drive circuit can be specified. Each of these pins is configured to drive by dividing 480 scanning lines, and sequentially outputs plasma pulses from the pins of the drive circuit 12a... In accordance with the scanning timing.

As indicated by the dashed line, the cursor processing section 7 outputs a cursor signal to be displayed in, for example, a defect detection mode for detecting a defective portion in an OSD (On Screen Display).
A) a cursor signal generating unit 7a for generating data, a synthesizing unit 7b for superimposing a cursor signal generated by the cursor signal generating unit 7a on video data, cursor position information (line number, driving of the liquid crystal column driver 8 or the plasma driver 12). Circuit and drive circuit pin numbers)
A combining unit 7 for superimposing cursor position information generated by a screen display signal generating unit 7c generated as data on image data
d.

The cursor signal generator 7a inputs cursor transition information input by a remote commander RC or the like by a special operation, for example, via the controller 14. Then, a cursor signal corresponding to the input cursor transition information is generated and output. The cursor signal is superimposed on a predetermined position of the video data (for each horizontal line) in the synthesizing unit 7b. The cursor position information generating section 7c generates and outputs the cursor position information according to the cursor transition information. The cursor position information output here is superimposed on a predetermined position of the video data by the synthesizing unit 7d. In this manner, the cursor signal and the cursor position information generated by the cursor processing unit 7 are superimposed on the video data by the synthesizing units 7b and 7d, supplied to the liquid crystal column driver 8, and drive the liquid crystal molecules by the plasma driver 12. This will cause it to be displayed on the screen.

FIG. 3 is a block diagram for explaining the cursor generating section 7a in detail. The cursor generating section 7a includes a horizontal cursor signal generating section 16, a vertical cursor generating section 17, and the like as shown by a dashed line. In this embodiment, an input selector switch SW1 and an output selector switch S1 are provided before and after each cursor generating unit.
W2 is provided, and cursor position information supplied from the control unit 14 is selected, and as will be described later with reference to FIGS.
Horizontal and vertical cursors are selected and displayed individually. Switching of these switches is controlled in conjunction with a command input to the control unit 14 from a special operation of the remote commander RC or an operation for maintenance.

First, the horizontal cursor generator 16 will be described. The horizontal cursor generator 16 includes a programmable counter 16a (hereinafter referred to as a P counter) and a gate 16b.
It is constituted by. The P counter 16a is provided with a preset terminal, a preset value input terminal, and a clock terminal. Cursor transition information by operation of the remote commander RC is generated by the preset input terminal, the control unit 14 generates an operation clock, a clock terminal, and a horizontal terminal. The synchronization pulse is input to a preset terminal. The operation clock is formed as a pulse having a cycle corresponding to the number of pixels in the horizontal direction.

Here, the signal waveform input to the cursor generator 16 and the cursor signal waveform superimposed on the video data within one horizontal scanning period (1H) will be described with reference to FIG. 4A is an operation clock, FIG. 4B is a horizontal synchronization pulse, FIG. 4C is an output of the P counter 16a,
4D shows an output of the gate 16b, FIG. 4E shows a video signal output from the video signal forming unit 18, and FIG. 4F shows a cursor signal superimposed on the video signal of FIG. 4E. The state is shown.

The P counter 16a is preset to the value of the cursor transition information every time a horizontal synchronizing pulse is input, and starts counting up according to the operation clock.
Then, as shown in FIG. 4 (c), the preset value is supplied as a count output to the gate 16b, and the gate 16b starts from the falling point of the input count output as shown in FIG. 4 (d). A cursor signal having a width of one clock is output. The output of the gate 16b is synthesized into a video signal by the synthesizing unit 7b.
The drive signal supplied to 0 is as shown in FIG. Then, by superimposing the cursor signal on the video data of all the scanning lines, the cursor signal is displayed as a line-shaped cursor Ch in the vertical direction as described later with reference to FIG.

Next, the vertical cursor generator 17 will be described. The vertical cursor generator 17 is, like the horizontal cursor generator 16, a programmable counter 17 a (hereinafter referred to as P
And a gate 17b.
The P counter 17a is provided with a preset terminal, a preset value input terminal, and a clock terminal. And
Cursor shift information by a user operation is input to a preset input terminal, an operation clock generated by the control unit 14 and synchronized with a horizontal frequency is input to a clock terminal, and a vertical synchronization pulse is input to a preset terminal. The operation clock is formed as a pulse having a cycle corresponding to the number of pixels in the horizontal direction, similarly to the one input to the horizontal cursor generation unit 16.

Here, the signal waveform input to the vertical cursor generator 17 and the cursor signal waveform superimposed on the video data within one vertical scanning period (1 V) will be described with reference to FIG. FIG. 5A shows an operation clock, and FIG.
5C shows a vertical synchronization pulse, FIG. 5C shows the output of the P counter 17a, FIG. 5D shows the output of the gate 17b, and FIG. 5E shows a state where the cursor signal is superimposed on the video signal.

The P counter 17a receives the vertical synchronizing pulse V1,
Each time V2... Is input, the value is preset to the value of the cursor shift information, and count-up is started according to the operation clock. Then, as shown in FIG. 5C, the preset value is supplied to the gate 17b as a count output, and the gate 17b outputs a cursor signal having one horizontal line width from the input count output. For example, when the cursor signal is output at the timing of the horizontal pulse H120 shown in FIG. 5B, all the one horizontal line corresponding to H120 becomes the cursor signal as shown in FIG. 5E. Then, the output of the gate 17b is synthesized into a video signal by the synthesizing unit 7d, and the PALC2
0 will be supplied. In this way, the cursor signal is superimposed on the position corresponding to the preset value based on the cursor transition information, and is displayed as the cursor Cv over one horizontal line as described later with reference to FIG.

In FIG. 3, the horizontal cursor generator 16,
Although the vertical cursor generator 17 is switched by the switches SW1 and SW2 to display only one of the cursors, the horizontal and vertical cursors are simultaneously displayed without the switches SW1 and SW2. May be.

When actually detecting a defective portion, the user first observes the screen to find a position that is abnormal, and moves the cursor to that position. For example, as shown in FIG. 6, when the conductive wire of the “B” color electrode indicated by hatching is broken (indicated by “x”), the “B” color does not develop and the cursor is moved to that position. By moving, a defective portion can be specified. However, "B"
In some cases, observation is difficult due to interference of the “R” color and the “G” color that are developed on both sides of the color. When the number of pixels increases, as shown in the schematic diagram of FIG. 7, a number of driving circuits R1, R2, G1
, G2, B1, B2,..., The driving electrodes (R, G, B,...) May be connected alternately from above and below. Doing so is not efficient.

Accordingly, for example, the R, G, and B colors are sequentially displayed in a single color by the video signal processing unit 3 shown in FIG. 1 and observed, and a defective portion is detected with respect to a specific color having an abnormality. Thereby, the detection efficiency is improved.

FIGS. 8A and 8B are horizontal directions, that is, FIG.
FIG. 4 is a diagram schematically illustrating an example of a case where a connection failure between the PALC 20 and the liquid crystal column driver 8 is detected. Here, it is assumed that the mode has shifted to the defect detection mode and the observation for each color has already been performed. For example, the 12th of the fourth drive circuit 8d of the liquid crystal column driver 8 driving the PALC 20
It is assumed that there is an abnormality such as a disconnection at the th pin. In this case, since no power is supplied to the electrode connected to the pin, the electrode appears on the screen of the PALC 20 as an abnormal point Ir as shown by a broken line in FIG. As described above, for example, 32 pins are led out to each of the drive circuits 8a, 8b, 8c,..., And therefore, the abnormal point Ir is the 108th (3 × 32 + 12 = 108) from the scanning start point.
Is connected to this pin.

The cursor Ch (dashed line) generated by the horizontal cursor generator 16 is displayed in a vertical line shape. Along with the cursor Ch, the line number where the cursor Ch generated by the cursor position information generating section 7c is located, the number of the drive circuit (IC), and the pin number of the drive circuit are indicated by numerical values. When a predetermined operator provided on the remote commander RC is operated to move the cursor Ch in the direction of the arrow (horizontal direction), the “line number”, “drive circuit number”, and “drive circuit pin number” are also incremented. (Or decrement),
As shown in FIG. 8B, when the cursor Ch is moved over the abnormal point Ir, numerical values such as a line number = 1100, a drive circuit number = 4, and a pin number = 12 are displayed. This makes it possible to detect, for example, that the twelfth pin of the fourth drive circuit 8d of the liquid crystal column driver 8 has a defect. Further, as shown in FIG. 7, the driving circuits R1, G1, B
.. Are connected, the cursor position information of, for example, the fourth drive circuit 12 for driving the “R” color
What is necessary is just to indicate that a failure has occurred in the th pin.

FIGS. 9A and 9B show the vertical direction, that is, P
FIG. 4 is a diagram illustrating an example of a case where a defective connection between the ALC 20 and the plasma driver 12 is detected. For example, PALC2
It is assumed that the twelfth pin of the third drive circuit 12c of the plasma driver 12 driving 0 has an abnormality such as disconnection. In this case, since no power is supplied to the electrode connected to the pin, the electrode appears on the screen of the PALC 20 as an abnormal point Ir as shown by a broken line in FIG. 9A.

The cursor Cv (dashed-dotted line) generated by the vertical cursor generation unit 17 corresponds to 1 corresponding to the plasma channel.
Displayed on a horizontal line. And this cursor Cv
In addition, the line number where the cursor Cv generated by the cursor position information generation unit 7b is located, and the driving circuit (I
The number C) and the pin number of the drive circuit are indicated by numerical values. When a predetermined operator provided on the remote commander RC is operated to move the cursor Cv in the direction of the arrow (vertical direction), the “line number”, “drive circuit number”, and “drive circuit pin number” are also incremented. (Or decremented), as shown in FIG.
When the cursor Cv is moved to the abnormal point Ir, numerical values such as line number = 230, drive circuit = 3, and pin number = 12 are displayed. This makes it possible to detect that a defect has occurred at the twelfth pin of the third drive circuit 12c of the plasma driver 12.

Note that the cursor Ch, shown in FIGS.
Cv may be displayed at the same time, and a defective portion in the connection state between the liquid crystal column driver 8 and the plasma driver 12 may be simultaneously detected. In addition, the display device is not limited to the plasma-addressed display device described in the embodiment. For example, the display unit is configured by a TFT-type liquid crystal display device, and the display unit and the scan driving unit are connected by a connector or the like. The present invention can be applied to any monitor device.

[0044]

As described above, the display device of the present invention displays a cursor for detecting a defective portion, and moves the cursor to the defective portion specified by observation in advance, so that the defective position can be changed from the cursor position to the defective portion. , And a pin number of the driving circuit and the like can be detected and specified. This makes it possible to quickly check the operation of the display unit and detect a defective portion during the manufacturing process or during service.

[Brief description of the drawings]

FIG. 1 is a block diagram of a plasma addressed liquid crystal display device according to an embodiment of the present invention. You.

FIG. 2 is a block diagram illustrating a cursor processing unit.

FIG. 3 is a block diagram illustrating a cursor generation unit constituting the cursor processing unit.

FIG. 4 is a diagram illustrating waveforms of signals related to the operation of a horizontal cursor generation unit.

FIG. 5 is a diagram illustrating waveforms of signals related to the operation of a vertical cursor generation unit.

FIG. 6 is a diagram illustrating an example of a disconnection state.

FIG. 7 is a diagram schematically showing a connection state between a drive electrode and a drive circuit.

FIG. 8 is a diagram illustrating a cursor generated by a horizontal cursor generation unit and an abnormal point on a screen.

FIG. 9 is a diagram illustrating a cursor generated by a vertical cursor generation unit and an abnormal point on a screen.

FIG. 10 is a diagram illustrating a PALC and a drive system of the PALC.

FIG. 11 is a diagram illustrating a structure of a PALC.

[Explanation of symbols]

16 horizontal cursor generator, 16a, 17a programmable counter, 16b, 17b gate, 17 vertical cursor generator, Ch, Cv cursor

Claims (3)

[Claims] A horizontal driver for supplying a video signal for each horizontal line to pixels arranged in a matrix, and a vertical driver for selectively sequentially supplying a drive signal to the horizontal lines. In a display device that scans a screen by the horizontal driver and the vertical driver to form an image, a cursor generating unit that generates a cursor that is displayed on the screen and that can be moved in pixel units based on input transition information, A display device comprising: cursor position information generating means for generating and displaying cursor display position information; and synthesizing means for superimposing the cursor and display position information on a video signal. 2. The display device according to claim 1, wherein the cursor is configured to be displayed in a line shape over a horizontal line and / or a vertical line. 3. The display device according to claim 1, wherein the transition information is configured to stop the cursor at an arbitrary position on a screen manually or automatically.