JP2008180962A - Laser repair method for liquid crystal panel, laser repair apparatus, and method for manufacturing the liquid crystal panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laser repair method for liquid crystal panel, capable of efficiently and stably performing laser repair of a defective pixel irrespective of the structure of a liquid crystal panel, a laser repair apparatus, and a method of manufacturing the liquid crystal panel. <P>SOLUTION: In the laser repair method for liquid crystal panel, emitting a laser beam toward the defective pixel of the liquid crystal panel, a laser beam, having a first spot size smaller than the minimum width dimension of the pixel, is emitted towards the defective pixel and a laser beam having a second spot size which is larger than the first spot size is emitted, while a gas bubble formed by the irradiation remains. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a laser repair method, a laser repair device, and a liquid crystal panel manufacturing method used for manufacturing a liquid crystal panel.

  Liquid crystal display devices are used in various home appliances and information terminal devices such as televisions, personal computers and mobile phones. In recent years, the defect rate has increased in the manufacturing process of an active matrix type liquid crystal display device with an increase in screen size and resolution. For example, if a TFT (Thin Film Transistor) malfunction or a defect such as a wiring layer or pixel electrode occurs, the alignment of the liquid crystal cannot be controlled, and a “bright spot defect” that is fixed at a high light transmittance occurs. There are things to do. Such bright spot defects degrade the display quality of the liquid crystal display device. In addition, among various defects that occur in the manufacturing process of the liquid crystal display device, the incidence of bright spot defects is high. However, it is technically very difficult to mass-produce liquid crystal display devices without generating defective pixels such as bright spot defects.

  Therefore, a liquid crystal display that irradiates such defective pixels with a laser to locally evaporate liquid crystals to form bubbles, disperses the alignment film into the bubbles, disturbs the orientation, and darkens the bright spot defects. A panel laser repair device is disclosed (for example, see Patent Documents 1 and 2). When bubbles are formed to facilitate the scattering of the alignment film, the alignment property of the alignment film can be sufficiently disturbed, and the light transmittance of defective pixels that are luminescent spot defects can be reduced.

However, the techniques disclosed in Patent Document 1 and Patent Document 2 have not taken into consideration the diversified structures of liquid crystal panels in recent years. Therefore, depending on the structure of the liquid crystal panel, there is a possibility that a portion where bubbles are not formed occurs and the success rate of the repair is lowered, or the bubbles spread beyond the defective portion and darken to the surrounding normal pixels.
JP-A-5-313167 JP 2003-149619 A

  The present invention provides a laser repair method for a liquid crystal panel, a laser repair device, and a method for manufacturing a liquid crystal panel, which can effectively and stably repair defective pixels regardless of the structure of the liquid crystal panel.

  According to one aspect of the present invention, there is provided a laser repair method for a liquid crystal panel that irradiates a laser toward a defective pixel of the liquid crystal panel, wherein the first spot diameter is smaller than the minimum width dimension of the pixel toward the defective pixel. And a laser having a second spot diameter larger than the first spot diameter while the bubbles formed by the irradiation stay in the laser. A repair method is provided.

  According to another aspect of the present invention, a laser oscillator that emits a laser, a stage on which a liquid crystal panel is placed, and the liquid crystal that is placed on the stage with the laser emitted from the laser oscillator. Optical means for leading to the panel, laser irradiation with a first spot diameter smaller than the minimum width dimension of the pixels of the liquid crystal panel, laser irradiation with a second spot diameter larger than the first spot diameter, And a laser repair apparatus characterized by comprising:

  According to another aspect of the present invention, a step of forming a liquid crystal panel by encapsulating liquid crystal between an array substrate and a counter substrate, a step of inspecting and finding defective pixels included in the liquid crystal panel, And a step of repairing the defective pixel by the laser repair method as described above.

  According to the present invention, there are provided a laser repair method, a laser repair device, and a liquid crystal panel manufacturing method for a liquid crystal panel that can effectively and stably repair a defective pixel regardless of the structure of the liquid crystal panel.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a flowchart for illustrating a laser repair method for a liquid crystal panel according to an embodiment of the present invention.
That is, in the present embodiment, first, a laser with a small spot diameter is irradiated toward the defective pixel of the liquid crystal panel to form bubbles (step S1). Here, bubbles are formed in the defective pixel because a part of the liquid crystal layer is evaporated by the laser energy when the defective pixel is irradiated with the laser.

  Next, a defective pixel is darkened by irradiating a laser toward the formed bubble (step S2). Here, the defective pixel is darkened because the alignment film exposed in the bubble is broken, vaporized and scattered by laser irradiation, and the deposit accumulates. This is because the orientation of the liquid crystal in contact with is disturbed.

  Next, if necessary, the laser irradiation position is moved to a desired location in the defective pixel, and laser irradiation is performed according to the above-described procedure (step S3). In this case, if a bubble already exists at the moved position, the laser for darkening can be irradiated (step S2) without irradiating the laser for forming the bubble (step S1).

Here, before describing the laser repair method according to the present embodiment, the structure of the liquid crystal panel W will be described first.
FIG. 2 is a schematic diagram for explaining the structure of the liquid crystal panel. FIG. 2A is a schematic cross-sectional view for illustrating the structure of a liquid crystal panel to be repaired, and FIG. 2B is a schematic plan view of the liquid crystal panel. Here, FIG. 2A is a cross-sectional view taken along line XX of FIG.

  As shown in FIG. 2A, the liquid crystal panel W has a structure in which the liquid crystal 30 is sandwiched between the array substrate 10 and the counter substrate 40. A polarizing plate (not shown) is provided on the surface opposite to the liquid crystal 30 for each of the array substrate 10 and the counter substrate 40. The array substrate 10 has a structure in which a glass substrate 12, an array region 15, a color filter 20 (20R, 20G, 20B), and an alignment film 25 are stacked. A structure in which the color filter 20 is formed on the array substrate 10 side in this manner is referred to as a “color filter on array (COA) structure”.

In the array region 15, openings for transmitting light are formed, and adjacent openings are partitioned by a light-shielding black matrix 50. Each portion partitioned by the black matrix 50 is referred to as a “pixel”. The pixel size is, for example, about 50 to 60 micrometers in width and about 150 to 200 micrometers in length. In the array region 15, in addition to the black matrix 50 that also serves as a wiring layer, for example, a switching element such as a TFT (Thin Film Transistor) (not shown), an auxiliary capacitance unit, an interlayer insulating film, a planarizing layer made of a resin, or the like. Is formed. A pixel electrode (not shown) is formed on the color filter 20.
On the other hand, the counter substrate 40 has a structure in which a glass substrate 45, a counter electrode 42, and an alignment film 35 are stacked.
With such a configuration, a predetermined driving voltage can be applied to the liquid crystal 30 for each pixel.

  Here, the color filter 20 generally includes a red (R) color filter 20R corresponding to the three primary colors of light, a green (G) color filter 20G, and a blue (B) color filter 20B. Consists of. The arrangement pattern of the color filters 20R, 20G, and 20B is, for example, as shown in FIG. 2B, in which the color filters of the same color are “striped” in the longitudinal direction of the pixels, and the color filters of each color are arranged in the lateral direction. Arranged periodically. In addition, the color filters for each color may be arranged in a staggered pattern, a mosaic pattern, a delta pattern, or the like.

  In such a liquid crystal panel W, the surface of the alignment film 25 formed on the array substrate 10 is often not always flat. For example, in the case illustrated in FIG. 2A, the green color filter 20G is formed thicker than the adjacent color filter 20B. As a result, a step S is generated between the color filters 20G and 20B, and the cell gap (thickness of the liquid crystal 30) D1 in the color filter 20B is larger than the cell gap D2 in the color filter 20G. As described above, when the thicknesses of the color filters 20R, 20G, and 20B are not the same, a step S is generated between the adjacent color filters.

The color filters 20R, 20G, and 20B are formed by a method such as photolithography, a printing method, or an ink jet method. In that case, depending on the order of formation of the color filters 20R, 20G, and 20B, a color filter formed later may be laminated on the end portion of the previously formed color filter, resulting in a step. Such a step between pixels is determined by the structure, the forming method, and the order of the color filter 20 and the like.
In addition to the color filter, a projection may be formed between adjacent pixels depending on the structure of the wiring and switching elements constituting the array region.
In addition, a spacer (for example, glass beads) (not shown) that determines the thickness of the liquid crystal 30 may be provided.

  These steps, protrusions, and the like are not necessarily formed uniformly among all the pixels, and are often formed only in a specific direction between specific pixels. Also, the spacers are not necessarily provided equally for all pixels.

Here, bubbles formed by laser irradiation do not always stay in the same position, and may move. According to the knowledge obtained by the present inventor, when there is a step or a protrusion, there is a tendency that bubbles tend to move from a narrower cell gap to a wider one. This is not necessarily clear, but the resistance when the bubbles move is higher when the cell gap is narrower, so the bubbles are more likely to move toward the wider cell gap. It is thought that this is because the bubbles move in a direction in which they can easily move. In addition, if there is a spacer, the formed bubbles may be broken or the growth of the bubbles may be hindered.
In this way, the movement and division of bubbles occur due to the structure of the liquid crystal panel such as the steps, protrusions, and spacers, which affects the success or failure of the repair.

For this reason, in the technique disclosed in Patent Document 1, there is a possibility that a bubble does not exist in the defective pixel due to the movement or division of the bubble, and a problem that such a portion cannot be repaired may occur. In that case, as in the technique disclosed in Patent Document 2, if a large bubble is formed so as to include the normal pixels around the defective pixel, the scattered objects are also scattered around the normal pixels. May accumulate and cause a new problem of darkening even normal pixels.
It is also conceivable to suppress the movement of bubbles by optimizing the irradiation conditions. However, in order to obtain appropriate conditions corresponding to the diversified structures of liquid crystal panels in recent years, there are a large number of related parameters, and even if appropriate conditions are required, it takes a lot of labor and time, and productivity is increased. There is a possibility that the problem of lowering may occur.

  As a result of the study, the present inventor first irradiates a laser with a small spot diameter to form a bubble in a part of the defective pixel, and then irradiates the formed bubble with a laser to darken a part of the defective pixel. After that, if the entire defective pixel is darkened by repeating this, the knowledge that the defective pixel can be repaired effectively and stably regardless of the structure of the liquid crystal panel was obtained. .

  FIG. 3 is a schematic diagram for explaining a laser repair method for the liquid crystal panel according to the present embodiment. Here, FIG. 3A is a schematic diagram for explaining laser spots used for bubble formation and darkening, and FIG. 3B is a diagram illustrating the laser repair method described in FIG. It is a schematic diagram for demonstrating visually. FIG. 3C is a schematic graph for explaining irradiation energy and irradiation timing of a laser used for bubble formation and a laser used for darkening.

  FIG. 3A shows a case where irradiation is performed so that the optical axis of the laser used for bubble formation and the optical axis of the laser used for darkening are substantially coaxial. The spot A laser is used for bubble formation, and the surrounding spot B laser is used for darkening.

  Here, it is preferable that the spot diameter of the laser (spot A) used for the bubble formation is sufficiently smaller than the minimum width dimension of the pixel. Further, the spot diameter of the laser (spot B) used for darkening is larger than that of the laser used for bubble formation, and as will be described later, the deposit generated by the bubble formation can be scattered again. It is preferable to use a size.

  If these spot diameters are illustrated, for example, the spot diameter of a laser (spot A) used for bubble formation is 2 micrometers or less, and the spot diameter of a laser (spot B) used for darkening is 5 micrometers in diameter. It can be over meters. However, it is not necessarily limited to these dimensions and can be appropriately changed.

  As a procedure of the laser repair method, first, as shown in the diagram on the left side of FIG. 3B, a laser with a small spot diameter (spot A) is radiated toward the defective pixel 55 of the liquid crystal panel so that the bubbles 80 are formed. Let it form.

  The reason why the bubbles 80 are formed by irradiating the laser with the small spot diameter is to prevent the bubbles 80 that are larger than necessary from being formed and the surrounding normal pixels from being darkened. As will be described later, it is also for making the range in which scattered matter is deposited as much as possible by laser irradiation in the presence of liquid crystal as small as possible.

The lower part of FIG. 3B is an enlarged view of the YY cross section of the left part. In addition, the same code | symbol is attached | subjected to the part similar to what was demonstrated in Fig.2 (a), and description is abbreviate | omitted.
When the laser is irradiated toward the pixel, liquid crystal is initially present in the irradiated portion, so that the liquid crystal in that portion is vaporized and bubbles 80 are formed. Then, a part of the alignment films 25 and 35 is vaporized, destroyed and scattered, and depressions 25a and 35a are formed in the parts, and the scattered particles are deposited as deposits 25b and 35b.

  Here, according to the knowledge obtained by the present inventor, the orientation of the liquid crystal in contact with the deposits 25b and 35b after the disappearance of the bubbles 80 is affected by the size (particle diameter) of the deposits 25b and 35b. Therefore, the size (particle diameter) of the deposits 25b and 35b is preferably determined in consideration of the orientation. However, in the initial laser irradiation, since the liquid crystal exists in the irradiated portion, a part of the irradiation energy is taken away by the temperature rise and vaporization of the liquid crystal, and the temperature of the alignment films 25 and 35 is controlled, and the alignment films 25 and 35 are destroyed. Control of vaporization becomes difficult. As a result, it is difficult to control the size (particle diameter) of the deposits 25b and 35b, and the repair success rate may be reduced.

  In the present embodiment, by irradiating with a laser having a small spot diameter, the range in which the deposits 25b and 35b, which are likely to have an inconvenient size (particle diameter) are deposited, is made as small as possible. Further, by irradiating with a laser having a small spot diameter, it is possible to suppress the formation of bubbles 80 that are larger than necessary, and to suppress the darkening due to the accumulation of scattered matter even in parts that are not necessary. I have to.

  Next, as shown in the center diagram of FIG. 3B, the formed bubble 80 is irradiated with a laser. At this time, the spot diameter of the laser to be irradiated is made larger than the spot diameter of the laser used for forming the bubble 80. As described above, if the alignment films 25 and 35 exposed in the bubble 80 are destroyed and vaporized by irradiating the laser beam toward the bubble 80, the size (particle diameter) of the deposits 25b and 35b is reduced. Control is also possible, and defective pixels can be repaired effectively and stably. In addition, deposits that are likely to have the above-mentioned inconvenient size (particle diameter) are obtained by, for example, irradiating the laser used for bubble formation and the laser used for darkening substantially coaxially. If it can be scattered again, almost all the deposits 25b and 35b can be made a size (particle diameter) convenient for the orientation.

The right side of FIG. 3B shows a case where the bubble 80 disappears due to heat dissipation after the end of laser irradiation, and the black dots in the figure indicate darkened portions.
Next, if necessary, the laser irradiation position is moved to a desired location in the defective pixel, and laser irradiation is performed according to the above-described procedure. In this case, if a bubble already exists at the moved position, the laser used for darkening can be irradiated without irradiating the laser used for forming the bubble (laser with a small spot diameter).

  It is also possible to specify a position where darkening is to be performed in a defective pixel by an image processing means (not shown) or the like, and to irradiate that portion with laser according to the above-described procedure. In this way, unnecessary laser irradiation is eliminated, so that damage to the liquid crystal panel W can be reduced and production efficiency can be increased.

  Further, after the laser irradiation, an inspection is performed by an image processing means (not shown), and when the degree of darkness does not reach a predetermined threshold value, the laser irradiation according to the above-described procedure can be performed again. In this way, the success rate of repair can be increased. Here, in the present embodiment, since the laser with a small spot diameter is irradiated to form the bubbles 80, it is possible to suppress the formation of the bubbles 80 that are larger than necessary even when the laser irradiation is performed again. Can do. Therefore, even in the case of re-irradiation, the influence on surrounding normal pixels can be minimized.

FIG. 3C is a schematic graph for explaining the irradiation energy and irradiation timing of a laser used for bubble formation and a laser used for darkening. The vertical axis represents irradiation energy and the horizontal axis represents time. .
In the figure, A1, A2, and A3 represent laser irradiation used for forming bubbles, and B1, B2, and B3 represent laser irradiation used for darkening. In addition, the bubble residence time in the figure refers to the time that the bubble 80 stays at the irradiation position of the laser used for darkening, and when this time elapses, the formed bubble 80 moves or disappears. I mean.

As shown in FIG. 3C, first, laser irradiation A1 used for forming the bubble 80 is performed. At this time, since the laser spot diameter is small, the energy is also low.
Next, laser irradiation B1 used for darkening is performed within the bubble residence time. Since the spot diameter of the laser at this time is larger than that in the case of the irradiation A1, the energy is also high.
Thereafter, irradiation A2 and irradiation B2, and irradiation A3 and irradiation B3 are performed in the same procedure. In addition, the frequency | count of irradiation is not necessarily limited to what was illustrated, It can change suitably.

  Here, if the timing of each irradiation is illustrated, the time between the laser irradiation used for forming the bubble 80 and the laser irradiation used for darkening is set to about several tens of microseconds to several hundreds of microseconds. The time between the laser irradiation used to form the bubble 80 and the laser irradiation used to form the next bubble 80 can be about 1 millisecond.

  The ratio of the laser irradiation energy used for forming the bubble 80 and the laser irradiation energy used for darkening can be about 1: 2 to 1: 3. Note that the energy densities of both may be the same.

As described above, according to the laser repair method of the liquid crystal panel according to the present embodiment, it is possible to sequentially repair so as to divide the defective pixel while forming bubbles of an appropriate size with a small spot diameter. Therefore, laser repair can be performed effectively and stably regardless of the structure of the liquid crystal panel.
Further, since the formed bubbles 80 do not become unnecessarily large, there is no possibility that even the surrounding normal pixels are darkened.
In addition, deposits that are likely to have an inconvenient size (particle diameter) can be scattered again, so that the repair success rate can be increased.
In addition, since the darkening laser is always applied to the alignment films 25 and 35 exposed in the bubble 80, the size (particle diameter) of the deposits 25b and 35b can be controlled, and the defective pixels can be effectively used. Laser repair can be performed efficiently and stably.
Therefore, the success rate of repair can be increased and the yield of products can be improved. In addition, since there is no possibility that even the surrounding normal pixels are darkened, the quality of the liquid crystal panel can be improved.

Next, a laser repair apparatus for a liquid crystal panel according to an embodiment of the present invention will be described.
FIG. 4 is a schematic view for illustrating a laser repair apparatus for a liquid crystal panel according to the first embodiment of the present invention.
As shown in FIG. 4A, the laser repair apparatus 100 for a liquid crystal panel includes a first laser oscillator 102 and a first laser that guides the laser emitted from the laser oscillator 102 to the liquid crystal panel W placed on the stage 115. Energy control unit 103, flattening optical system 104, condensing lens 105, mask 106, beam combining prism 107, dichroic mirror 108, imaging lens 109, second laser oscillator 110, and laser oscillator 110, an energy control unit 111, a reflection mirror 112, an image detection unit 113, an image detection unit lens 114, a stage 115, which are second optical means for guiding the laser emitted from the laser beam 110 to the liquid crystal panel W placed on the stage 115. Etc.

  The first laser oscillator 102 emits a laser for forming the bubble 80. As a laser source of the laser oscillator 102, for example, a YAG laser having a wavelength of about 1064 nanometers can be used. The energy control unit 103 adjusts the energy intensity of the laser emitted from the laser oscillator 102. The flattening optical system 104 includes a fly-eye lens (Fly-Eye Lenz) and the like, and uniformizes the energy intensity of the laser. The condensing lens 105 condenses the laser, and the mask 106 narrows the spot diameter. The beam combining prism 107 causes the optical axis of the laser emitted from the laser oscillator 102 and the optical axis of the laser emitted from the laser oscillator 110 to be substantially coaxial. Therefore, as shown in FIG. 4B, the laser beams emitted from both can irradiate a substantially coaxial position on the defective pixel. The circle in FIG. 4B represents the spot diameter at the laser irradiation position, the laser emitted from the laser oscillator 102 is the center spot A, and the laser emitted from the laser oscillator 110 is the substantially coaxial spot B. It becomes. The dichroic mirror 108 has a function of turning the laser emitted from the laser oscillator 102 or the laser oscillator 110 back to the imaging lens 109 side and transmits light incident from the imaging lens 109 side to the image detection unit lens 114 side. It has a function to make it. The imaging lens 109 focuses the laser emitted from the laser oscillator 102 or the laser oscillator 110 on the defective pixel surface.

  The second laser oscillator 110 emits a laser for darkening. As a laser source of the laser oscillator 110, for example, a carbon dioxide laser can be used. The YAG laser described above can also be used. The energy control unit 111 adjusts the energy intensity of the laser emitted from the laser oscillator 110. The reflection mirror 112 turns the laser emitted from the laser oscillator 110 back to the beam combining prism 107 side.

  For example, a CCD (Charge Coupled Device) sensor can be used as the image detection unit 113. The image detection unit lens 114 enlarges an image to be captured and forms an image on the image detection unit 113. The image information obtained from the image detection unit 113 is processed by a processing unit (not shown), and is used for specifying the laser irradiation position, inspection after irradiation, positioning of the irradiation position, and the like.

  The stage 115 places and holds the liquid crystal panel W and moves the liquid crystal panel W. In addition, although not shown, illumination means for illuminating the imaging surface to facilitate imaging, the first laser oscillator 102, the energy control unit 103, the second laser oscillator 110, the energy control unit 111, and the image detection unit 113, stage 115, control means for controlling each operation of the illumination means (not shown), a database storing defect data of the liquid crystal panel W, and the like are appropriately provided.

  Next, the operation of the laser repair apparatus 100 will be described.

First, the liquid crystal panel W is placed on the stage 115 by a conveying means (not shown). The placed liquid crystal panel W is positioned on a stage 115 after being positioned by positioning means (not shown).
Next, based on the defect information stored in a database (not shown), the stage 115 moves so that the defective pixel to be repaired can be irradiated with the laser.
Next, the laser used for forming the bubble 80 is irradiated toward the defective pixel. In other words, the energy emitted from the laser oscillator 102 is adjusted by the energy control unit 103, the energy intensity is made uniform by the flattening optical system 104, condensed by the condenser lens 105, and the spot diameter is made by the mask 106. The aperture is focused, and the defective pixel is irradiated through the beam combining prism 107, the dichroic mirror 108, and the imaging lens 109. In this case, since the spot diameter on the irradiated surface can be small as shown in A of FIG. 4B, the bubbles 80 of an appropriate size can be formed as described above.

  Next, the irradiation from the laser oscillator 102 is stopped, and the irradiation from the laser oscillator 110 is performed. That is, the laser emitted from the laser oscillator 110 is adjusted in energy intensity by the energy control unit 111, and is irradiated to the defective pixel via the reflection mirror 112, the beam combining prism 107, the dichroic mirror 108, and the imaging lens 109. In this case, the optical axis of the laser emitted from the laser oscillator 102 and the optical axis of the laser emitted from the laser oscillator 110 are substantially coaxial by the beam combining prism 107. In addition, the spot diameter on the irradiation surface is set to be larger than the above-described A as shown in B of FIG. Therefore, irradiation is performed also on the deposit generated by the laser irradiation from the laser oscillator 102, and the deposit can be re-scattered as described above. This irradiation is performed within the bubble residence time as described with reference to FIG. Therefore, the alignment films 25 and 35 exposed in the bubble 80 can always be irradiated with laser, and the size (particle diameter) of the deposits 25b and 35b can be controlled. Laser repair can be performed.

  Next, if necessary, the laser irradiation position is moved to a desired location in the defective pixel by the stage 115, and laser irradiation is performed according to the above-described procedure. In this case, if a bubble already exists at the moved position, the laser used for darkening can be irradiated without irradiating the laser used for forming the bubble (laser with a small spot diameter). In this case, the presence or absence of the bubble 80 is detected and determined by the image detection unit 113.

  Further, the position where darkening should be performed in the defective pixel can be detected and judged by the image detection unit 113, and the laser irradiation can be performed on the portion by the above-described procedure. In this way, unnecessary laser irradiation is eliminated, so that damage to the liquid crystal panel W can be reduced and production efficiency can be increased.

  Further, after the laser irradiation, detection and inspection are performed by the image detection unit 113, and when the degree of darkness does not reach a predetermined threshold value, the laser irradiation according to the above-described procedure can be performed again. In this way, the success rate of repair can be increased. Here, in the present embodiment, since the laser with a small spot diameter is irradiated to form the bubbles 80, it is possible to suppress the formation of the bubbles 80 that are larger than necessary even when the laser irradiation is performed again. Can do. Therefore, even in the case of re-irradiation, the influence on surrounding normal pixels can be minimized.

  Next, if necessary, the laser irradiation position is moved to the next defective pixel by the stage 115, and laser irradiation is performed according to the above-described procedure. When all the repairs in the liquid crystal panel W are completed, the liquid crystal panel W is carried out by a conveying means (not shown).

As described above, according to the laser repair apparatus for a liquid crystal panel according to the present embodiment, it is possible to sequentially repair so as to divide a defective pixel while forming bubbles of an appropriate size with a small spot diameter. Therefore, laser repair can be performed effectively and stably regardless of the structure of the liquid crystal panel.
Further, since the formed bubbles 80 do not become unnecessarily large, there is no possibility that even the surrounding normal pixels are darkened.
In addition, deposits that are likely to have an inconvenient size (particle diameter) can be scattered again, so that the repair success rate can be increased.
In addition, since the darkening laser is always applied to the alignment films 25 and 35 exposed in the bubble 80, the size (particle diameter) of the deposits 25b and 35b can be controlled, and the defective pixels can be effectively used. Laser repair can be performed efficiently and stably.

  Therefore, the success rate of repair can be increased and the yield of products can be improved. In addition, since there is no possibility that even the surrounding normal pixels are darkened, the quality of the liquid crystal panel can be improved.

FIG. 5 is a schematic view for illustrating a laser repair apparatus for a liquid crystal panel according to the second embodiment of the present invention.
In addition, the same code | symbol is attached | subjected to the part equivalent to what was demonstrated in FIG. 4, and description is abbreviate | omitted.

  A laser repair apparatus 200 for a liquid crystal panel includes a laser oscillator 202, an optical path switching unit 203 that is an optical unit that guides a laser beam emitted from the laser oscillator 202 to a liquid crystal panel W placed on a stage 115, an energy control unit 103, a flat surface Optical system 104, condenser lens 105, mask 106, beam combining prism 107, dichroic mirror 108, imaging lens 109, energy control unit 111, reflection mirror 112, image detection unit 113, image detection unit lens 114, stage 115, etc.

The laser oscillator 202 emits a laser for forming and darkening the bubble 80. As a laser source of the laser oscillator 202, for example, a YAG laser having a wavelength of about 1064 nanometers can be used.
The optical path switching unit 203 switches the optical path in response to a command from a control unit (not shown), and switches the laser emitted from the laser oscillator 202 to the formation and darkening of the bubble 80. That is, when the bubble 80 is formed, the optical path of the laser emitted from the laser oscillator 202 is switched to the optical path L1 side by the optical path switching unit 203, the energy intensity is adjusted by the energy control unit 103, and the energy is obtained by the flattening optical system 104. The intensity is made uniform, the light is condensed by the condensing lens 105, the spot diameter is narrowed by the mask 106, and the defective pixel is irradiated through the beam combining prism 107, the dichroic mirror 108, and the imaging lens 109. In this case, since the spot diameter on the irradiation surface can be small as shown in A of FIG. 4B, the bubbles 80 of an appropriate size can be formed as described above.

  When darkening, the optical path of the laser emitted from the laser oscillator 202 is switched to the optical path L2 side by the optical path switching unit 203, the energy intensity is adjusted by the energy control unit 111, the reflection mirror 112, the beam coupling prism The defective pixel is irradiated through 107, the dichroic mirror 108, and the imaging lens 109. In this case, due to the beam combining prism 107, the optical axis of the laser from the optical path L1 side and the optical axis of the laser from the optical path L2 side are substantially coaxial. In addition, the spot diameter on the irradiation surface is set to be larger than the above-described A as shown in B of FIG. Therefore, irradiation is also performed on the deposit generated by the laser irradiation from the optical path L1 side, and the deposit can be re-scattered as described above. This irradiation is performed within the bubble residence time as described with reference to FIG. Therefore, the alignment films 25 and 35 exposed in the bubble 80 can always be irradiated with laser, and the size (particle diameter) of the deposits 25b and 35b can be controlled. Can be laser repaired.

  In addition, although not shown, illumination means for illuminating the imaging surface to facilitate imaging, laser oscillator 202, optical path switching means 203, energy control unit 103, energy control unit 111, image detection unit 113, image detection unit A lens 114, a stage 115, control means for controlling each operation of the illumination means (not shown), a database storing defect data of the liquid crystal panel W, and the like are provided as appropriate.

  The operation of the laser repair apparatus 200 is the same as that of the laser repair apparatus 100 described with reference to FIG. 4 except for the switching of the optical path by the optical path switching means 203 described above, and a description thereof will be omitted.

  As described above, according to the laser repair device 200 of the liquid crystal panel according to the present embodiment, it is possible to enjoy the same effect as the laser repair device 100 described in FIG. Further, since only one laser oscillator 202 is required, the apparatus can be reduced in size and simplified.

Next, a method for manufacturing the liquid crystal panel according to the present embodiment will be described.
For convenience of explanation, a method of manufacturing a TFT (Thin Film Transistor) color liquid crystal display panel will be described.

  The manufacturing process of the TFT color liquid crystal display panel includes a TFT array forming process, a color filter forming process, an alignment film forming process, a substrate bonding process, a liquid crystal injection process, and a substrate cutting process.

  Here, the laser repair method according to the present embodiment described above is performed after the liquid crystal injection step or after the substrate cutting step. That is, after the liquid crystal is sealed between the array substrate and the counter substrate to form the liquid crystal panel W, the defective pixel included in the liquid crystal panel W is inspected, and if there is a defective pixel, the laser repair according to the present embodiment is performed. The defective pixel is repaired by the method.

  In addition, since the technique of each well-known process can be applied except for the laser repair method according to the present embodiment described above, description thereof will be omitted.

As described above, according to the liquid crystal panel manufacturing method according to the present embodiment, it is possible to sequentially repair so as to divide the defective pixel while forming bubbles of an appropriate size with a small spot diameter. Regardless of the structure of the liquid crystal panel, laser repair can be performed effectively and stably.
Further, since the formed bubbles 80 do not become unnecessarily large, there is no possibility that even the surrounding normal pixels are darkened.

In addition, deposits that are likely to have an inconvenient size (particle diameter) can be scattered again, so that the repair success rate can be increased.
In addition, since the darkening laser is always applied to the alignment films 25 and 35 exposed in the bubble 80, the size (particle diameter) of the deposits 25b and 35b can be controlled, and the defective pixels can be effectively used. Laser repair can be performed efficiently and stably.
Therefore, the success rate of repair can be increased and the yield of products can be improved, and the quality of the liquid crystal panel can also be improved because there is no possibility that even the surrounding normal pixels are darkened.

The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples.
For example, although a YAG laser and a carbon dioxide laser have been exemplified as the laser source, the present invention is not limited to this, and various lasers such as an excimer laser can be used.
Further, the shape, size, material, arrangement, and the like of each element of the laser repair device described above are not limited to those illustrated, but are included in the scope of the present invention as long as the gist of the present invention is included.
Further, even if various modifications and additions are made by those skilled in the art for each element of the liquid crystal panel laser repair method and the liquid crystal panel manufacturing method, they are included in the scope of the present invention as long as the gist of the present invention is included. The
Moreover, each element with which each specific example mentioned above is provided can be combined as much as possible, and what combined these is also included in the scope of the present invention as long as the gist of the present invention is included.

3 is a flowchart for illustrating a laser repair method for a liquid crystal panel according to an embodiment of the present invention; It is a schematic diagram for demonstrating the structure of a liquid crystal panel. It is a schematic diagram for demonstrating the laser repair method of the liquid crystal panel which concerns on this Embodiment. It is a schematic diagram for illustrating the laser repair apparatus of the liquid crystal panel which concerns on the 1st Embodiment of this invention. It is a schematic diagram for illustrating the laser repair apparatus of the liquid crystal panel which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

  25, 35 Alignment film, 25b, 35b Deposit, 30 Liquid crystal, 80 bubbles, 100 Laser repair device, 102 First laser oscillator, 110 Second laser oscillator, 200 Laser repair device, 202 Laser oscillator, 203 Optical path switching means , A spot, A1 to A3 irradiation, B spot, B1 to B3 irradiation, L1 optical path, L2 optical path, W liquid crystal panel

Claims (5)

A liquid crystal panel laser repair method for irradiating a laser toward a defective pixel of a liquid crystal panel,
Irradiating the defective pixel with a laser having a first spot diameter smaller than the minimum width dimension of the pixel;
A laser repair method for a liquid crystal panel, wherein a laser having a second spot diameter larger than the first spot diameter is irradiated while bubbles formed by the irradiation stay.   2. The laser repair method for a liquid crystal panel according to claim 1, wherein the laser having the first spot diameter and the laser having the second spot diameter are irradiated so that their optical axes are substantially coaxial.   3. The liquid crystal panel according to claim 1, wherein the laser irradiation with the first spot diameter and the laser irradiation with the second spot diameter are performed at a plurality of locations in the defective pixel. 4. Laser repair method. A laser oscillator for emitting a laser;
A stage on which a liquid crystal panel is placed;
Optical means for guiding the laser emitted from the laser oscillator to the liquid crystal panel mounted on the stage;
Control means for controlling laser irradiation with a first spot diameter smaller than the minimum width dimension of a pixel of the liquid crystal panel and laser irradiation with a second spot diameter larger than the first spot diameter;
A laser repair device comprising: Forming a liquid crystal panel by enclosing liquid crystal between the array substrate and the counter substrate;
Inspecting and finding defective pixels contained in the liquid crystal panel;
A method of manufacturing a liquid crystal panel comprising: repairing the defective pixel by the laser repair method according to claim 1.

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