JP2006091673A - Manufacturing method for liquid crystal display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method for a liquid crystal display which is not influenced by the behavior of an air bubble and with which stable repair quality is obtained. <P>SOLUTION: The manufacturing method for the liquid crystal display 10 which is constituted by sandwiching a liquid crystal material 13 between an array substrate 11 and a counter substrate 12 and has a plurality of pixels 23 includes: an information generation step of detecting an electric signal from a pixel electrode 15 of each pixel 23 formed on the array substrate 11 and generating positional information of a 2nd defect pixel 23A to be repaired on the basis of the electric signal; a sticking step of sticking the array substrate 11 and counter substrate 12 together after the information generation step; a laser irradiation step of making the 2nd defect pixel 23A being a repair target be irradiated with pulse laser light L on the basis of the positional information after the sticking step; and an injection step of injecting the liquid crystal material 13 into a space between the array substrate 11 and counter substrate 12 after the laser irradiation step. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing a liquid crystal display having a step of darkening defective pixels such as defective bright spots.

  Of the defects that occur in the manufacturing process of the liquid crystal display, the pixels that always transmit light are called bright spot defects. This bright spot defect is very conspicuous, and usually it cannot be shipped as a product if there is even one.

  On the other hand, a pixel that always blocks light is called a dark spot defect. However, since this dark spot defect is less noticeable than a bright spot defect, it is often permitted even if it exists. Therefore, in the manufacturing process of the liquid crystal display, a dark spot repair for changing the bright spot defect found in the lighting evaluation into a dark spot defect may be performed.

  There are roughly two types of dark spot repairs: electrical methods and optical methods. The former is a method of preventing voltage from being applied to the pixel electrode by cutting or short-circuiting the wiring on the liquid crystal substrate. With this method, the darkness level after repair is 100%, but there are some that can be repaired and some that cannot be repaired due to the cause of the bright spot failure, and the repair rate is low.

  The latter is a method of reducing light transmittance by generating fine particles in a pixel by laser irradiation and depositing the fine particles on an alignment film. With this method, repair is possible regardless of the cause of the bright spot failure, so the repair rate is high. However, it is difficult to determine the conditions for obtaining a sufficient darkness level. In particular, the repair method of scanning pixels with a pulse laser focused on a small spot diameter is difficult in terms of [1] to [3] below.

[1] In order to darken all the pixels with defective bright spots, the generated fine particles need to be scattered not only to the scanning path of the pulse laser but also to the periphery thereof.

[2] In order to disperse the fine particles, it is necessary that bubbles exist in the liquid crystal layer near the irradiation point of the pulse laser.

[3] In order to deposit fine particles with a stable density and distribution, it is necessary to make the bubbles sufficiently large or to set the scanning path and scanning speed in accordance with the growth and movement of the bubbles.

  Next, the conventional dark spot repair will be described with reference to FIG.

  FIG. 4 is an explanatory diagram for explaining the state of the conventional dark spot repair.

  When scanning of the bright spot defect 100 by the pulse laser L is started, bubbles 102 are generated in the liquid crystal layer 101 in the vicinity of the irradiation point of the pulse laser L, and materials such as the ITO 103, the alignment films 104a and 104b, and the color filter 105 are formed. Fine particles 106 are generated.

The fine particles 106 scatter in the bubbles 102 and deposit on the surfaces of the alignment films 104a and 104b, thereby forming irregularities 110 on the surface of the array substrate 107 and the counter substrate 108 that are in contact with the liquid crystal layer 109. Thereby, the orientation of the liquid crystal layer 109 is lowered, and the bright spot defect 100 is darkened.
JP-A-8-15660

  When performing the optical darkening repair by the conventional method, the quality is greatly influenced by the behavior of the bubbles. For this reason, there is a problem in that stable repair quality cannot be obtained and it takes too much time to manufacture a liquid crystal display that can be shipped as a product.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method for manufacturing a liquid crystal display that is not affected by the behavior of bubbles and that can obtain stable repair quality. .

  In order to solve the above-described problems and achieve the object, the liquid crystal display manufacturing method of the present invention is configured as follows.

(1) In a method of manufacturing a liquid crystal display having a plurality of pixels, in which a liquid crystal material is sandwiched between an array substrate and a counter substrate, an electrical signal is detected from the pixel electrode of each pixel formed on the array substrate, and the electrical signal An information creation process for creating position information of a pixel to be repaired based on the above, a bonding process for bonding the array substrate and the counter substrate after the information creation process, and a position after the bonding process A laser irradiation step of irradiating the pixel to be repaired with a laser based on information; and an injection step of injecting the liquid crystal material between the array substrate and the counter substrate after the laser irradiation step. Features.

  According to the present invention, stable repair quality that is not affected by the behavior of bubbles can be obtained.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 is a cross-sectional view of a liquid crystal display 10 according to an embodiment of the present invention.

  As shown in FIG. 1, the liquid crystal display 10 has an array substrate 11 and a counter substrate 12. The array substrate 11 and the counter substrate 12 are arranged to face each other with a gap G of about 5 μm, and a liquid crystal material 13 is sealed between them.

  The array substrate 11 has a transparent glass substrate 14, an ITO pixel electrode 15 and a PI alignment film 16 are sequentially formed on the surface of the liquid crystal material 13, and on the opposite surface of the liquid crystal material 13. A polarizing film 17 is attached.

  On the other hand, the counter substrate 12 has a transparent glass substrate 18, and a color filter 19 composed of RGB three colors, an ITO conductive thin film 20, and a PI alignment film 21 are sequentially formed on the surface of the liquid crystal material 13. A polarizing film 22 is affixed to the opposite surface of the liquid crystal material 13.

  FIG. 2 is a process diagram showing a manufacturing process of the liquid crystal display 10 according to the embodiment.

  As shown in FIG. 2, the array substrate 11 is first manufactured (step S1). Then, the charge amount of each pixel electrode 15 of the array substrate 11 is measured by the array tester, and a pixel 23 whose charge amount is out of the specified range (hereinafter referred to as “first defective pixel 23”) is detected. The position information (hereinafter referred to as “first position information”) is created. Note that the first defective pixel 23 whose charge amount is out of the specified range may be a defective pixel such as a so-called bright spot defect that always transmits light when the liquid crystal display 10 is turned on.

  The first defective pixel 23 is repaired based on the first position information, and the first defective pixel 23 (hereinafter referred to as “second defective pixel”, which is not improved even if the repair is performed). 23A ") is detected, and its position information (hereinafter referred to as" second position information ") is created (step S2). It should be noted that the second defective pixel 23A that does not become a good spot even when the good spot repair is performed has a very high possibility of a defective pixel such as a bright spot defect.

  On the other hand, the counter substrate 12 is manufactured in a separate process from the above process (step S3).

  When the creation of the second position information and the manufacture of the counter substrate 12 are completed, the array substrate 11 and the counter substrate 12 are bonded together at an interval of about 5 μm (step S4). Then, the bonded array substrate 11 and counter substrate 12 are divided for each screen, that is, for each liquid crystal display 10 (step S5).

  Next, the second defective pixel 23A is scanned by the pulse laser L based on the second position information created by the array tester. As a result, the second defective pixel 23A is darkened prior to the lighting evaluation (step S6). The manner in which the second defective pixel 23A is scanned with the pulse laser L to darken will be described in detail later.

  Next, the liquid crystal material 13 is injected into the gap G between the array substrate 11 and the counter substrate 12, and the periphery thereof is sealed with a sealing material (not shown) (step S7). Then, polarizing plates 17 and 22 are attached to the surfaces of the array substrate 11 and the counter substrate 12 opposite to the liquid crystal material 13 (step S8), and the liquid crystal display 10 is completed.

  When the liquid crystal display 10 is completed, lighting evaluation is performed and it is inspected whether there is a bright spot defect on the display screen of the liquid crystal display 10 (step S9). If there is no bright spot defect by this inspection, it is conveyed to the next step.

  Next, how the second defective pixel 23A is darkened (step S6) will be described in detail.

  FIG. 3 is an explanatory diagram for explaining a state of the second dark spot repair according to the embodiment.

  First, the second defective pixel 23A is scanned with the pulse laser L based on the second position information. As a result, the alignment films 16 and 21, the pixel electrode 15, the conductive thin film 20, the color filter 19 and the like at positions corresponding to the second defective pixels 23A are processed, and fine particles 30 made of these materials are generated in the vicinity thereof. .

  The fine particles 30 scatter in the gap G between the array substrate 11 and the counter substrate 12 and are deposited on the alignment films 16 and 21. Thereby, irregularities 31 are formed on the inner surfaces of the array substrate 11 and the counter substrate 12, and the orientation of the liquid crystal material 13 is lowered. As a result, as described above, the second defective pixel 23A is darkened prior to the lighting evaluation of the liquid crystal display 10.

  What is important here is that before the liquid crystal material 13 is injected into the gap G between the array substrate 11 and the counter substrate 12, the second defective pixel 23A is scanned with the pulse laser L, and the inner surfaces of the array substrate 11 and the counter substrate 12 are uneven. 31 is formed.

  Therefore, the fine particles 30 generated by the irradiation of the pulse laser L can be freely scattered in the gap G between the array substrate 11 and the counter substrate 12 without being obstructed by the liquid liquid crystal material 13. The fine particles 30 are deposited with a substantially uniform density and distribution over the entire two defective pixels 23A, and the second defective pixels 23A can be reliably darkened.

  As a result, a situation in which a bright spot failure is found in the lighting evaluation performed after the completion of the liquid crystal display 10 and repair is performed is reduced, so that the manufacturing time of the liquid crystal display 10 is shortened and thus productivity is improved. be able to.

  In addition, this invention is not limited to the said embodiment, In an implementation stage, a component can be deform | transformed and embodied in the range which does not deviate from the summary. Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above embodiments. For example, some components may be deleted from all the components shown in the embodiment.

1 is a cross-sectional view of a liquid crystal display according to an embodiment of the present invention. Process drawing which shows the manufacturing process of the liquid crystal display which concerns on the same embodiment. Explanatory drawing explaining the mode of the darkening repair of the 2nd defective pixel which concerns on the embodiment. Explanatory drawing for demonstrating the mode of the conventional darkening repair.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Liquid crystal display, 11 ... Array substrate, 12 ... Opposite substrate, 13 ... Liquid crystal material, 15 ... Pixel electrode, 23 ... Pixel, 23A ... Second defective pixel, L ... Pulse laser.

Claims (1)

In a manufacturing method of a liquid crystal display having a plurality of pixels, wherein a liquid crystal material is sandwiched between an array substrate and a counter substrate,
An information creation step of detecting an electrical signal from the pixel electrode of each pixel formed on the array substrate and creating position information of a pixel to be repaired based on the electrical signal;
After the information creation step, a bonding step of bonding the array substrate and the counter substrate;
After the bonding step, a laser irradiation step of irradiating the pixel to be repaired with a laser based on the position information;
After the laser irradiation step, an injection step of injecting the liquid crystal material between the array substrate and the counter substrate;
A method of manufacturing a liquid crystal display, comprising:

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