JPH06138426A - Method for correcting pixel defect - Google Patents

Abstract

PURPOSE:To provide a correcting method for pixel defect which can control transmitted light without any deterioration of a liquid crystal. CONSTITUTION:A gate electrode 2, a gate insulating film 3, a drain electrode 4, and a source electrode 5 are provided on an insulating substrate 1. A signal line 6 is connected to the drain electrode 4 and a pixel electrode 7 is connected to the source electrode 5 to form an array substrate 8. On an insulating substrate 9, a counter electrode 10 is formed to form a counter electrode substrate 11. The array substrate 8 and counter electrode substrate 11 are opposed to each other through the liquid crystal 12 to form a liquid crystal display device 15. When the supply of a signal to one pixel electrode 7 becomes abnormal, light is transmitted continuously at all times to cause the bright point defect that only the single pixel illuminates. A shield body 21 is provided on a light transmission part at the insulating substrate 1 of the array substrate 8 and then the bright point defect can easily be made into a dimmed point defect which does not transmit the light and is relatively inconspicuous.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pixel defect repairing method for repairing pixel defects in a dot-shaped transparent portion where light continues to be transmitted.

[0002]

2. Description of the Related Art A conventional method for correcting a pixel defect will be described with reference to FIGS.

A conventional liquid crystal display device having a TFT (Thin Film Transistor) is constructed as shown in FIGS.

That is, a gate electrode 2 is formed on an insulating substrate 1 such as a glass substrate, and a gate insulating film 3 is formed on the insulating substrate 1 so as to cover the gate electrode 2. The drain electrode 4 and the source electrode 5 are provided on the gate electrode 2 with the gate insulating film 3 interposed therebetween, the signal line 6 is connected to the drain electrode 4, and the source electrode 5 is provided on the gate insulating film 3. The pixel electrodes 7 formed on a plane are connected to the pixel electrodes 7, and the pixel electrodes 7 are arranged in a matrix to form an array substrate 8.

On the other hand, a counter electrode 10 and a counter electrode substrate 11 are formed on the insulating substrate 9 such as a glass substrate which faces the insulating substrate 1 in the same manner.

Further, the array substrate 8 and the counter electrode substrate
The liquid crystal display device 15 is formed by facing 11 via the liquid crystal 12.

Then, for example, when the supply of a signal to a certain pixel electrode 7 becomes abnormal, a voltage is not applied to this pixel electrode 7, light is always transmitted, and a voltage on the screen is not applied. Only the pixel corresponding to 7 may continue to emit light and become a bright spot.

In the case where the signal supply to the pixel electrode 7 is abnormal, in order to make the pixel electrode 7 inconspicuous on the screen and the point where light does not always pass, the gate electrode 2 and the gate electrode 2 are conventionally used by a laser. , A voltage is applied to the pixel electrode 7 by forming the conductive portion 16 on the source electrode 5 and short-circuiting, and forcibly no light is transmitted by an electric means, that is, a voltage is applied to the liquid crystal 12 so as to become a dark spot. is doing.

[0009]

However, in the case of the above-mentioned conventional technique, it is possible to make the portion corresponding to the abnormal pixel electrode 7 the dark spot where no light is transmitted at all times, but it is always 50. It is impossible to control such that only% or 30% of light is transmitted.

Further, depending on the driving method, a direct current component may be continuously applied between the pixel electrode 7 and the counter electrode 10, which is a dark point at which light does not pass initially.
Since a direct current voltage is applied from the pixel electrode 7 to the liquid crystal 12, the liquid crystal molecules may be destroyed and eventually become a bright spot where light continues to be transmitted to the corresponding portion of the liquid crystal 12.

Further, a thin film fragment forming the gate electrode 2 or the pixel electrode 7 which is generated when the gate electrode 2 and the source electrode 4 are short-circuited by using a laser,
There is also a problem that the pixel electrode 7 or the liquid crystal 12 may be adversely affected.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a method of correcting a pixel defect capable of controlling transmitted light without deterioration of liquid crystal.

[0013]

DISCLOSURE OF THE INVENTION The present invention provides a pixel defect repairing method for repairing a pixel defect in a dot-shaped transmissive portion where light is always transmitted in an image display surface of the liquid crystal display device. After completion of the above step, a shield is provided on the light transmitting portion of the pixel defect.

[0014]

According to the present invention, a shield is provided at a bright spot defect where light is always transmitted, so that a bright spot defect that always transmits light and a conspicuous bright spot defect that does not always transmit light can be easily made into an inconspicuous dark spot defect. You can Further, unlike the conventional method, since the correction method does not require thin film destruction by laser, it is not necessary to consider the influence of the thin film generated at the time of pixel destruction on other pixels.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method of correcting a pixel defect of a liquid crystal display device according to an embodiment of the present invention will be described below with reference to the drawings. The parts corresponding to those of the conventional example shown in FIGS. 7 and 8 are designated by the same reference numerals for description.

As shown in FIGS. 1 and 2, a liquid crystal display device having a TFT (Thin Film Transistor) has a gate electrode 2 formed on an insulating substrate 1 such as a glass substrate.
A gate insulating film 3 is formed on the entire surface of the insulating substrate 1 so as to cover the gate electrode 2. The drain electrode 4 and the source electrode 5 are provided on the gate electrode 2 with the gate insulating film 3 interposed therebetween, the signal line 6 is connected to the drain electrode 4, and the gate insulating film 3 is connected to the source electrode 5.
Pixel electrodes 7 to be pixels formed on a plane are connected to the upper side, and the pixel electrodes 7 are arranged in a matrix to form an array substrate 8.

On the other hand, a counter electrode 10 and a counter electrode substrate 11 are formed on the insulating substrate 9 such as a glass substrate so as to face the insulating substrate 1 in the same manner.

Further, the array substrate 8 and the counter electrode substrate
The liquid crystal display device 15 is formed by facing 11 via the liquid crystal 12.

A lamp (not shown) is provided on either one of the liquid crystal display devices 15, and light is emitted from this lamp to project an image through the liquid crystal 12.

In a normal state, a voltage is applied to the gate electrode 2 by the signal of the signal line 6, the timing is measured, and the voltage is applied to the pixel electrode 7 to set the contents for projection.

On the other hand, the drain electrode 4 or the source electrode 5
If the signal supply to a certain pixel electrode 7 becomes abnormal due to breakage or poor contact between the signal line 6 and the drain electrode 4, no voltage is applied to this pixel electrode 7, and light is constantly transmitted. Then, only the pixels to which no voltage is applied on the screen are continuously illuminated, and only a single pixel corresponding to the pixel electrode 7 having an abnormality on the screen is illuminated, resulting in a bright spot defect.

In this case, as shown in FIG.
By providing the shield 21 in the light transmitting portion of the insulating substrate 1, the bright spot defect can be easily formed into a dark spot defect that does not transmit light that is relatively inconspicuous even after the liquid crystal display device 15 is completed.

Further, as the shielding method, in addition to the method of completely shielding the light, a shield 21 for partially transmitting the light is used as shown in FIGS.
The pixel electrode 7 that has an abnormality by a method of transmitting light to the inside, a method of using a shield that transmits a certain amount of light, a method of obtaining a desired transmittance by using a colored shield, or the like. You can adjust the light that passes through.

Further, the shield 21 may be installed at a position corresponding to the abnormal pixel electrode 7 on the insulating substrate 9 of the counter electrode substrate 11, as shown in FIG.

Further, as shown in FIG. 7, a polarizing plate 22 may be provided on the surface side of the counter electrode substrate 11, and a shield 21 may be provided on the polarizing plate 22.

According to the above-mentioned embodiment, since it is not necessary to break the thin film by the laser unlike the conventional case, it is not necessary to consider the influence of the thin film generated at the time of breaking on the other pixel electrodes 7 or the liquid crystal 12.

Further, since the shield 21 is provided on the insulating substrates 1 and 9 or the deflection plate 22, the correction can be performed even after the liquid crystal display device 15 is completed.

[0028]

According to the pixel defect correcting method of the present invention,
By placing a shield on the portion of the bright spot defect through which light always passes, a conspicuous bright spot defect through which light always passes can be easily made into an inconspicuous dark spot defect through which light does not always pass through.
Further, unlike the conventional method, since the correction method does not require thin film destruction by laser, it is not necessary to consider the influence of the thin film generated at the time of pixel destruction on other pixels.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a liquid crystal display device of an embodiment of the present invention.

FIG. 2 is an enlarged front view showing the above liquid crystal display device.

FIG. 3 is a sectional view showing a liquid crystal display device of another embodiment of the same as above.

FIG. 4 is an enlarged front view showing the above liquid crystal display device.

FIG. 5 is a cross-sectional view of a liquid crystal display device showing another embodiment of the above.

FIG. 6 is a sectional view of a liquid crystal display device showing still another embodiment of the same.

FIG. 7 is a cross-sectional view showing a conventional liquid crystal display device.

FIG. 8 is an enlarged front view showing a conventional liquid crystal display device.

[Explanation of symbols]

 7 Pixel electrode as a pixel 21 Shield

Claims (1)

[Claims] 1. A method of repairing a pixel defect in a dot-shaped transmissive portion in which light is constantly transmitted in an image display surface of a liquid crystal display device, the method comprising: repairing a pixel defect after completion of the liquid crystal display device; A method of repairing a pixel defect, which comprises providing a shield on a transparent portion of the pixel.