KR101214045B1 - Method and device for repairing brightness defect of liquid crystal display panel - Google Patents

Abstract

Disclosed are a method and a bright point repair apparatus for repairing a bright point defect of a liquid crystal display panel. A method of repairing bright spot pixels of a liquid crystal display panel using a laser processing device, comprising: irradiating a first laser beam to a color filter of a bright spot pixel portion of a liquid crystal display panel to form a modified layer in which the color filters are blackened; A method of repairing a bright point of a liquid crystal display panel comprising a step of separating a modified layer from an upper substrate by a laser beam, and forming a light blocking layer by depositing a modified layer separated by a third laser beam on a pixel surface of the lower substrate. According to the present invention, the laser is irradiated directly to the color filter to undergo the pigment modification step, the separation step, and the deposition step, thereby effectively darkening the bright pixel and repairing the bright spot defect.

Description

Method and device for repairing bright spot of liquid crystal display panel {Method and device for repairing brightness defect of liquid crystal display panel}

The present invention relates to a method and apparatus for repairing a bright point defect of a liquid crystal display panel.

A liquid crystal display panel is a device using optical anisotropy and polarization properties of a liquid crystal. A display device converts and transmits various electrical information into visual information by using liquid crystal transmittance which is changed by adjusting an arrangement direction of liquid crystal molecules according to an applied voltage. to be. Such liquid crystal display panels are widely used in that they have low operating voltage and low power consumption.

The liquid crystal display panel is classified into a TN mode, a VA mode, an IPS mode, and the like according to its operation mode. It is classified according to the arrangement method of the liquid crystal molecules and the alignment method of the liquid crystal molecules by voltage, which greatly affects the viewing angle and response speed of each mode.

Such liquid crystal display panels have various pixel defects, such as color defects, bright spot defects, dark spot defects, and defects due to short circuits. Among these, the bright spot defect is a defect caused by the pixel being always on and always displaying white, and the dark spot defect is a defect caused by the pixel being always turned off and always displaying black.

In general, black dots on a white background are not well recognized, but white dots on a black background are well recognized, and a bright point defect is most visible to a user as compared to a dark point defect. In addition, the number of bright point pixels that is also generally accepted is stricter than the number of dark point pixels. Therefore, it is possible to blacken a bright pixel and to improve the yield of a liquid crystal display panel.

In order to correct such a defect of bright spots, a bright spot repair operation using a laser is recently used.

1 is a cross-sectional view of a liquid crystal display panel irradiated with a laser according to a bright point repair method using a conventional laser.

Referring to FIG. 1, the liquid crystal display panel 1 includes a first array substrate 10 (hereinafter referred to as a “C / F substrate”) and a second array substrate 20 that face each other with the liquid crystal layer 30 therebetween. (Hereinafter referred to as 'TFT substrate').

The C / F substrate 10 includes a black matrix 18 for preventing light leakage sequentially formed on the upper substrate 12, and color filters 14 of R, G, and B for implementing red, green, and blue colors. And an organic thin film layer 16 made of an organic material, an ITO film, or the like, in order to planarize the surface of the color filter 14.

The TFT substrate 20 includes gate wirings and data wirings defining unit pixel regions formed on the lower substrate 22, thin film transistors 24 formed at intersections of the gate wirings and data wirings, and thin film transistors 24. And a pattern of a pixel electrode connected to apply a voltage for driving the liquid crystal layer 30.

An alignment film (not shown) formed on the inner side to determine the initial orientation of the liquid crystal layer 30 and a common electrode (not shown) for applying a reference voltage for driving the liquid crystal layer 30 to face the pixel electrode are not shown. It may be further included in the F substrate 10 and / or the TFT substrate 20.

For the liquid crystal display panel 1 having such a structure, when the bright point defect is found in the bonding step of the C / F substrate 10 and the TFT substrate 20 and the inspection step after the liquid crystal injection step is completed, the bright pixel is darkened. As a method for ignition, a laser is irradiated to the black matrix to melt the black matrix, and the melted black matrix material is guided to the foreign material to darken the bright pixels.

The method of diffusing the black matrix into the color filter includes forming a gap to form a dark ignition layer (i.e., a light blocking layer) inside the color filter, decomposing the black matrix as a raw material for dark ignition, and dissolving the decomposed black matrix material. It consists of a diffusion step into the filter. According to this, there are various technical and method limitations, such as difficult to carry out a process process and a long repair time.

First, there is a technical limitation that can be applied only when the pigment component of the black matrix, which is a raw material for dark ignition, is an organic substance.

In addition, there is a problem that the thin films burst due to a large amount of bubbles generated during processing in forming a gap in the color filter to introduce a black matrix, which is a raw material for dark ignition, into the color filter. In this case, as the thin film bursts, the ITO fragment, the organic thin film fragment, and the ionic material flow into the liquid crystal layer, thereby limiting the method of affecting the display driving quality.

In addition, due to the enlargement of the liquid crystal display panel and the improvement of the aperture ratio in the decomposition step of the black matrix, the area of the pixel is relatively too large compared to the amount of the black matrix required for darkening, so that it is difficult to form a uniform dark spot region and to form a light blocking layer. Since the amount of the matrix is relatively small compared to the pixel area, the thinly formed light blocking layer may not completely block the light from the backlight. When a large amount of black matrix pigment is used to thicken a thin light blocking layer, when a constant thickness cannot be maintained, there is a method limit in which light leakage occurs between pixels.

In the diffusion step of introducing the decomposed black matrix material into the color filter in the repairing step, the overlapped laser is irradiated to the processed color filter in the gap forming step, and various organic materials covering the color filter and color filter corresponding to the pixel area are applied. There is a difficulty in how the thin film, ITO electrode, etc. explode, and finally, there is a fatal technical and method problem that requires a considerable processing time (for example, 10 minutes or more) for a high quality defective pixel repair. . However, when there is an overcoat layer on the C / F substrate of the liquid crystal display panel, even if bubbles within a predetermined amount occur during the repair process, the thin film does not burst within the turnover stress value of the overcoat layer, and defective pixel repair of good quality may be achieved. .

Such a method of diffusing the black matrix into the color filter is a poor quality pixel repair method, but it is limited to only the model having the overcoat layer in the liquid crystal display panel, and thus it is applicable. Recently, in order to reduce the cost of the liquid crystal display panel, domestic and foreign manufacturers have applied a technology for manufacturing a liquid crystal display panel without using an overcoat layer in mass production. Therefore, for the liquid crystal display panel without the overcoat layer, it is difficult to use the above-described method, and there is a need for a method which has been replaced or improved.

In order to overcome the technical and method limitations of the conventional method, a method of darkening a bright pixel by changing the color of the color filter black by irradiating and carbonizing a color filter in a region corresponding to the bright pixel is used.

The repair method by direct blackening of the color filter has to follow a complicated processing method in order to repair one defective pixel of the repair method using the conventional black matrix, requires a very long processing time, and the black matrix is an organic pigment component. It can be applied only to the phosphorus model, it is limited only to the model with the overcoat layer, and it is a method that can overcome many technical and method limitations such as the difficulty of repairing the enlarged liquid crystal display panel.

In the case of the direct blackening method of the color filter, since the color filter is directly blackened using a laser, processing can be performed regardless of the increased pixel size and various pixel shapes of each panel manufacturer due to the enlargement of the liquid crystal display panel. For example, the repair time can be shortened to 2 to 3 seconds. Further, by directly processing the pigment constituting the color filter, a light blocking layer can be formed regardless of the pigment component of the black matrix. In addition, the pigments constituting the color filter are blackened to form a thick light blocking layer, thereby improving the problems according to the conventional method, such as having a higher light blocking effect than the light blocking effect of the conventional light blocking layer using the black matrix.

However, during the process of directly carbonizing the color filter, there is a problem in that impurities including the color filter, the pixel electrode or the common electrode ITO, the alignment layer PI, and the like introduced into the liquid crystal layer may not be prevented from flowing into the liquid crystal layer.

2 is an optical image of a thin film layer on the surface of a color filter after laser processing when the conventional color filter is directly blackened. Referring to FIG. 2, it can be seen that impurities falling into the liquid crystal layer as the thin film bursts by bubbles generated during laser processing affect the driving of the liquid crystal.

In addition, in this process, the color filter is composed of a polymer-based material and exhibits a heat-sensitive reaction when carbonized with a laser. Thus, an ionic material is generated, and the ionic material is combined with a peripheral TFT electrode or a liquid crystal to resist the pixel electrode. Phenomena such as increased value and / or lowered voltage holding ratio. As a result, an electric field or / and a current value formed between the pixel electrode and the common electrode may not be applied for a predetermined time through the liquid crystal, and thus, normal pixels around the processing area may malfunction.

An ionic material generated during carbonization at a high temperature generates a high temperature light emission phenomenon, that is, pixel unevenness, in which peripheral normal pixels emit abnormally, and needs to be solved to improve product yield.

The above-described background technology is technical information that the inventor holds for the derivation of the present invention or acquired in the process of deriving the present invention, and can not necessarily be a known technology disclosed to the general public prior to the filing of the present invention.

The present invention is to provide a method and apparatus for repairing a bright spot of a liquid crystal display panel by irradiating a laser directly to a color filter to undergo a pigment modification step, a separation step, and a deposition step to effectively darken the bright spot pixel to repair the bright spot defect. .

In addition, the present invention is a bright point repair method of a liquid crystal display panel in the conventional color filter direct blackening method to prevent impurities introduced into the liquid crystal layer by bursting the lower organic thin film layer of the lower layer due to bubbles generated during color filter processing and It is for providing a device.

In addition, the present invention is a lower peak covering the color filter and the color filter corresponding to the pixel area by irradiating a femtosecond laser having a high peak power and a heat effect generated during processing to generate heat only within the bright pixel to be processed. The present invention provides a method and apparatus for bright spot repair of a liquid crystal display panel in which an organic thin film layer is deposited on a lower substrate in a pixel shape.

In addition, the present invention, unlike the conventional light blocking layer formed on the upper substrate of the liquid crystal display panel is formed in the lower substrate by blocking the light from the backlight in the vicinity of the backlight to the light in a wider area of the pixel area It is to provide a bright point repair method and apparatus of a liquid crystal display panel by improving the repair quality by being blocked over.

Other objects of the present invention will be readily understood through the following description.

According to an aspect of the present invention, a method of repairing bright spot pixels of a liquid crystal display panel using a laser processing apparatus, the color filter of the bright spot pixel portion of the liquid crystal display panel is irradiated with a laser beam to blacken the color filter and from the upper substrate There is provided a bright point pixel repair method that forms a light blocking layer that separates and deposits on a pixel surface of a lower substrate to block light from a backlight.

The organic thin film layer positioned under the color filter may also be modified to form a modified layer.

The spot of the laser beam may be uniformly scanned corresponding to the size of the bright pixel or the shape of the laser beam may be irradiated to correspond to the size of the bright pixel.

The laser beam may be a pulse laser consisting of pulses having an energy of 0.95 to 1.76 nJ.

When the liquid crystal display panel operates in one of the TN mode and the VA mode, the laser beam may be irradiated through one of the upper substrate and the lower substrate.

When the liquid crystal display panel operates in the IPS mode, the laser beam can be irradiated through the upper substrate.

According to an aspect of the present invention, a method of repairing bright spot pixels of a liquid crystal display panel using a laser processing apparatus, wherein the color filter is blackened by irradiating a first laser beam to the color filter of the bright spot pixel portion of the liquid crystal display panel. Forming a layer, separating the modified layer from the upper substrate by the second laser beam, and depositing the modified layer separated by the third laser beam onto the pixel surface of the lower substrate to form a light blocking layer. A bright point repair method of a liquid crystal display panel is provided.

In the modified layer forming step, the organic thin film layer positioned under the color filter may be modified together to form the modified layer.

The separation step may be performed by scanning a spot of the second laser beam uniformly corresponding to the size of the bright pixel or by forming and irradiating a shape of the second laser beam to correspond to the size of the bright pixel.

The first laser beam, the second laser beam, and the third laser beam may have high laser outputs.

The first laser beam may be a pulse laser including pulses having an energy of 0.05 to 0.70 nJ, a second laser beam of 0.71 to 0.94 nJ, and a third laser beam of 0.95 to 1.76 nJ.

When the liquid crystal display panel operates in one of the TN mode and the VA mode, the first laser beam, the second laser beam, and the third laser beam may be radiated through one of the upper substrate and the lower substrate. Alternatively, when the liquid crystal display panel operates in the IPS mode, the first laser beam, the second laser beam, and the third laser beam may be irradiated through the upper substrate.

On the other hand, according to another aspect of the present invention, a method for repairing the bright pixel of the liquid crystal display panel using a laser processing apparatus, a modified layer in which the color filter is blackened by irradiating a laser beam to the color filter of the bright pixel portion of the liquid crystal display panel A method of repairing a bright point of a liquid crystal display panel is provided, including forming a light emitting layer, separating the modified layer from the upper substrate, and depositing the separated modified layer on the pixel surface of the lower substrate.

In the modified layer forming step, the organic thin film layer positioned under the color filter may be modified together to form the modified layer.

The separation step may be performed by scanning a spot of the laser beam uniformly corresponding to the size of the bright pixel or by forming and irradiating a shape of the laser beam to correspond to the size of the bright pixel.

The laser beam may be a pulse laser consisting of pulses having an energy of 0.95 to 1.76 nJ.

When the liquid crystal display panel operates in one of the TN mode and the VA mode, the laser beam may be irradiated through one of the upper substrate and the lower substrate. Alternatively, when the liquid crystal display panel operates in the IPS mode, the laser beam may be irradiated through the upper substrate.

On the other hand, according to another aspect of the present invention, a bright spot repair device for repairing a bright spot of a liquid crystal display panel, the laser generating unit for generating a laser beam of a predetermined condition, the laser beam is received and irradiated to the color filter of the bright pixel portion The blackening part forming the modified layer in which the color filter is blackened, the separating part receiving the laser beam and irradiating the modified layer to separate the modified layer from the upper substrate, and receiving the laser beam and irradiating the separated modified layer. Provided is a bright point repair apparatus including a deposition unit in which a modified layer forms a light blocking layer deposited on a pixel surface of a lower substrate.

The blackening unit may also denature the organic thin film layer positioned under the color filter.

The separation unit may scan the spot of the laser beam uniformly corresponding to the size of the bright pixel or form the shape of the laser beam to correspond to the size of the bright pixel.

The laser generation unit may cause the laser beams used in the blackening unit, the separation unit, and the deposition unit to sequentially have a high laser output.

The laser generation unit may allow the laser beam to be composed of pulses having an energy of 0.95 to 1.76 nJ.

When the liquid crystal display panel operates in one of the TN mode and the VA mode, the laser beam may be transmitted through one of the upper substrate and the lower substrate. Alternatively, when the liquid crystal display panel operates in the IPS mode, the laser beam may be radiated through the upper substrate.

On the other hand, according to another aspect of the present invention, a liquid crystal display panel repaired by the above-described bright point repair method, a color filter corresponding to the bright point pixel portion is blackened and separated from the upper substrate is deposited on the pixel surface of the lower substrate light blocking layer A liquid crystal display panel is provided.

Other aspects, features, and advantages will become apparent from the following drawings, claims, and detailed description of the invention.

According to an embodiment of the present invention, the laser is irradiated directly to the color filter to undergo a pigment modification step, a separation step, and a deposition step, thereby effectively darkening the bright pixel and repairing the bright spot defect.

In addition, it can be applied regardless of the size, structure, material, etc. of the pixel to be processed, can solve the problems caused by the inflow of impurities or / and ionic substances in the liquid crystal layer, and in the color filter processing in the conventional color filter direct blackening method Due to the bubbles generated, the lower organic thin film layer in the lower layer bursts, thereby preventing impurities from flowing into the liquid crystal layer.

In addition, the femtosecond laser, which has a high peak power and heat effects generated during processing, is irradiated to generate heat only within the bright pixels to be processed, so that the color filter corresponding to the pixel area and the lower organic thin film layer covering the color filter are It is effective to deposit the pixel shape on the lower substrate.

In addition, unlike the conventional light blocking layer formed on the upper substrate of the liquid crystal display panel, the light blocking layer is formed on the lower substrate so that light from the backlight is blocked in the vicinity of the backlight so that light in the bright pixel area is blocked over a larger area. As a result, the repair quality can be improved.

1 is a cross-sectional view of a liquid crystal display panel irradiated with a laser in accordance with a bright spot repair method using a conventional laser.
2 is an optical image of a thin film layer on the surface of a color filter after laser processing by a method of directly blackening a conventional color filter.
3 is a view showing a schematic configuration of a laser processing apparatus used to correct a bright point defect of a liquid crystal display panel according to an embodiment of the present invention.
4 is a block diagram showing a configuration of a bright point repair apparatus of a liquid crystal display panel according to an embodiment of the present invention.
5 is a flowchart of a bright point repair method of a liquid crystal display panel according to an exemplary embodiment of the present invention.
6A to 6C are views illustrating a state of a liquid crystal display panel according to each process of the bright point repair method according to an embodiment of the present invention.
7 is a view showing spot processing and area processing when performing a separation step according to an embodiment of the present invention.
8 is an optical image of the surface of the color filter after the bright spot repair according to an embodiment of the present invention.
FIG. 9 is an optical image of a light blocking layer deposited on a lower substrate of a liquid crystal display panel after bright spot repair according to an embodiment of the present invention. FIG.
10A through 10C are three-dimensional images and thickness measurements of light blocking layers for red, green, and blue pixels, respectively.
Fig. 11A is a schematic diagram illustrating a method of irradiating a laser on a TFT substrate and a development image according to an embodiment of the present invention.
FIG. 11B is a schematic diagram illustrating a method of irradiating a laser on a C / F substrate according to another embodiment of the present invention. FIG.
12 is a view showing a result of performing a bright spot repair by irradiating a laser on each of a TFT substrate and a C / F substrate in a liquid crystal display panel operating in IPS mode.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated in the drawings and described in detail in the detailed description. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a view showing a schematic configuration of a laser processing apparatus used to correct a defect of a liquid crystal display panel according to an embodiment of the present invention. Referring to FIG. 3, the laser generator 110, the optical modulator 120, the beam dump 125, the reflection mirror 130, the beam expander 140, the scanner 150, the objective lens unit 160, and the stage The unit 170, the liquid crystal display panel 1, and the path 115 of the laser beam are shown.

The laser processing apparatus according to the present embodiment is characterized by performing fine precision processing by using an ultra-short laser pulse. The laser beam having the ultra short laser pulse is oscillated by the laser generator 110, modulated by the optical modulator 120, and directed to the beam dump 125 or the reflection mirror 130. The laser beam traveling to the reflective mirror 130 is magnified through the beam expander 140, scanned by the scanner 150, and mounted on the stage 170 through the objective lens unit 160. Is irradiated to the color filter layer belonging to the bright pixel. Here, the reflective mirror 130 may be omitted along the path 115 of the laser beam. This will be described in detail for each part as follows.

The laser generator 110 includes a laser medium, a pumping unit, a switching unit, and the like to output a laser beam having a predetermined pulse width. The laser beam oscillated by the laser generator 110 may be an ultra-short laser pulse having a pulse width in femto-second units.

When using a laser beam having an extremely short pulse, the pulse duration is shorter than the thermal diffusion time, so that the target exposed to the laser beam with high energy intensity can be removed in a short time because there is no energy transfer between the electron and the lattice. As a result, a melting zone or a heat affected zone is hardly observed in the portion to which the laser beam is irradiated. In addition, the length of the laser pulse absorbed and diffused in any material is proportional to the width of the laser pulse. The ultra short laser pulse has a short duration and a diffusion length in which the laser pulse is absorbed and diffused into the processing part. It also shortens, enabling precision machining.

The optical modulator 120 modulates the laser beam so that a part thereof is directed toward the objective lens unit 160 (first path), and the other part is adjusted to be irradiated to the beam dump 125 (second path). It plays a role. The scheme may be an Acoustic Optic Modulator (AOM) or an Electro Optic Modulator (EOM).

Since the optical modulator 120 has a faster response than a shutter or motor driving mirror which is generally used, it is suitable for controlling the laser processing time at a high speed.

In this embodiment, the response time of the optical modulator 120 is within 110 ns / mm, and can be closed after opening only for a desired processing time in conjunction with the position of the target measured by the position measuring unit, which will be described later. The time can vary from a few microseconds to a few seconds depending on the target.

Here, the amount of the laser beam to be adjusted may be one or more of the number of laser pulses, irradiation time, and the like. In the case of adjusting the number of laser pulses, as many or more pulses necessary for correcting a defect of the liquid crystal display panel 1 among the pulses of the laser beam generated from the laser generator 110 are routed to the objective lens unit 160. The amount of pulses is controlled by branching the remaining pulses to another path, such as the bypass path (in this embodiment, to the beam dump 125). When the number of pulses of the laser beam generated from the laser generator 110 is a natural number unit, the optical modulator 120 may adjust the amount of pulses by separating the number of pulses, that is, the quantity. In the case of adjusting the irradiation time, the laser beam is in the continuous wave mode, and the path is set so that the laser beam travels to the objective lens unit 160 only for a predetermined irradiation time or additionally a predetermined time or more. do.

The optical modulator 120 calculates the amount of laser pulses required to process the target according to the size of the target, and controls the operation of the optical modulator 120 to direct the laser pulse corresponding to the calculated amount to the objective lens unit 160. Modulation control unit (not shown) may be added. The modulation control unit may be integrally formed with the optical modulator 120, may be connected to a separate device, or may be integrated with an apparatus control unit (not shown) that controls the entire laser processing apparatus.

That is, the optical modulator 120 may determine the path of travel of the laser beam according to the on / off signal from the modulation controller corresponding to the irradiation time. That is, the path of the laser beam is deflected by deflecting the laser beam from the laser generating unit 110 to the objective lens unit 160 when the on signal is applied, and deflecting the laser beam to the beam dump 125 when the off signal is applied. Can be separated.

The scanner 150 corresponds to a focus adjusting unit, and finely horizontally moves the focus of the laser beam on the processing surface. The scanner 150 may be a galvano mirror installed with two mirrors facing each other.

The first galvano mirror receives and reflects the laser beam and rotates about the first axis. The second galvano mirror receives and reflects a laser beam reflected from the first galvano mirror while rotating about a second axis different from the first axis. Therefore, the laser beam can be irradiated to a desired point on the stage unit 170 by adjusting the angle between the first and second axes, the degree of rotation of the first galvano mirror, and the degree of rotation of the second galvano mirror. Do.

After the scanner 150 positions the laser beam at a specific point, the objective lens unit 160 collects the laser beam with finely adjusted focus and irradiates a target to be processed. Here, the objective lens unit 160 may be composed of a single objective lens, a plurality of lens groups such as a convex lens, a concave lens may be composed of, or may be composed of a combination of one or more lenses and other optical systems. .

The scanner 150 may be provided with a scanner controller (not shown) for controlling the operation of the scanner 150 so that the laser beam can be irradiated to the corresponding position according to the position of the target. The scanner controller may be integrated with the scanner 150, may be connected to a separate device, or may be integrated into the device controller for controlling the entire laser processing apparatus.

In the present embodiment, in order to denature, separate, and / or deposit the target (color filter layer) of the liquid crystal display panel 1, the position, shape, size, height, etc. of the bright pixel must be measured, and the laser beam is applied to the bright pixel area. The objective lens unit 160 should be focused so that it can be irradiated correctly.

To this end, a position measuring unit (not shown) capable of capturing bright spot pixels using an image pickup camera and receiving the photographed information to determine the location of the bright spot pixels may be added. Like the above-described modulation control unit or scanner control unit, the position measuring unit may be formed integrally with or separately from other devices, and may be integrated with the device control unit. In this embodiment, the position measuring unit may include all the devices for measuring the position using the imaging camera, a detailed description thereof will be omitted. In addition, an auto focus system for receiving a signal from the imaging camera and focusing the objective lens unit 160 may be added.

The stage unit 170 is a portion for placing the liquid crystal display panel 1, and the distance and / or position with respect to the objective lens unit 160 may be adjusted to adjust the exact position and focus. To this end, a stage component 170 may be added a mechanical component that enables movement, rotation, and the like.

The path of the laser beam is from the laser generator 110 to the liquid crystal display panel 1 on the stage 170 via the optical modulator 120, the beam expander 140, the scanner 150, and the objective lens unit 160. Is set to face, the path may be changed according to the configuration of the laser processing apparatus and the reflective mirror 130 is used for this purpose.

In the present exemplary embodiment, an apparatus controller for controlling overall driving of the laser generator 110, the optical modulator 120, the scanner 150, and the stage unit 170 may be provided. The device control unit may be a conventional computer including a CPU, a ROM, and a RAM, and checks a target to be processed through an imaging camera and a position measuring unit, and generates a laser beam, modulates and irradiates a laser beam through an output of a control signal. Positioning, focal length movement, stage portion movement and rotation can be controlled.

In addition, according to the present embodiment, it is preferable to use a laser beam in a wavelength region with good absorption depending on the pigment material constituting the color filter layer. To this end, the laser processing apparatus may further include a wavelength converter (not shown) that receives the laser beam generated by the laser generator 110 and converts the laser beam into a laser beam having an appropriate wavelength. In the present embodiment, the wavelength converter may include any device for converting the wavelength of the laser beam, and a detailed description thereof will be omitted.

In this embodiment, the laser generator 110, the optical modulator 120, the reflection mirror 130, the beam expander 140, the scanner 150, and the objective lens unit 160 are optically connected. Optical phenomena include various phenomena such as reflection, diffraction, and refraction of light. Here, 'optically connected' means that light emitted from one component by various optical phenomena is received by the other component. it means.

4 is a block diagram illustrating a configuration of a bright spot repair apparatus of a liquid crystal display panel according to an embodiment of the present invention, and FIG. 5 is a flowchart of a bright spot repair method of a liquid crystal display panel according to an embodiment of the present invention, and FIG. 6A. 10C are views illustrating a state of a liquid crystal display panel according to each process of the bright spot repair method according to an embodiment of the present invention, and FIG. 7 illustrates spot processing and area processing when a separation step is performed according to an embodiment of the present invention. 8 is an optical image of a surface of a color filter after bright spot repair according to an embodiment of the present invention, and FIG. 9 is a light difference deposited on a lower substrate of a liquid crystal display panel after bright spot repair according to an embodiment of the present invention. 10A to 10C show a three-dimensional image and a thickness measurement value of a light blocking layer for each of a red pixel, a green pixel, and a blue pixel. A tanaen drawings.

Referring to FIGS. 3 and 6A to 6C, the bright spot repair apparatus 200, the laser generating unit 210, the blackening unit 220, the separating unit 230, the deposition unit 240, the liquid crystal display panel 1, C / F substrate 10, TFT substrate 20, liquid crystal layer 30, upper substrate 12, color filter 14, organic thin film layer 16, black matrix 18, lower substrate 22, The thin film transistor 24, the modified layer 40, the isolation material 50, and the light blocking layer 60 are shown.

In the present embodiment, for convenience of understanding and explanation of the invention, it is assumed that the bright pixel of the liquid crystal display panel 1 corresponds to a green color filter, but the scope of the present invention is not limited thereto. Of course.

The bright point repair apparatus 200 of the liquid crystal display panel according to the present exemplary embodiment includes a laser generator 210, a blackening unit 220, a separation unit 230, and a deposition unit 240.

The laser generator 210 generates a laser beam having a condition suitable for each step when correcting a defect of the liquid crystal display panel 1. For example, the laser generator 210 may generate a femtosecond laser beam having a pulse repetition rate of 85 MHz to modify the pigment constituting the color filter 14. In this case, if the laser power is about 5mW, the energy per pulse is about 0.0588nJ, which is very small value, so it can be seen as a continuous laser.

The blackening unit 220 receives the laser beam generated by the laser generating unit 210 and irradiates the color filter 14 corresponding to the bright pixel portion of the liquid crystal display panel 1. The pigment constituting the color filter 14 may be modified by the laser beam irradiated from the blackening unit 220 to form a modified carbonized layer 40 directly (step S310). Referring to FIG. 6A, a state in which a modified layer 40 is formed by irradiating a laser beam to a green color filter in a bright pixel portion is illustrated.

In addition, when the overcoat layer, which is the organic thin film layer 16 that protects the color filter 14, exists in the liquid crystal display panel 1 according to the exemplary embodiment, the color filter 14 may be positioned below the color filter 14. The organic thin film layer 16 protecting the color filter 14 may also be modified together to form the modified layer 40.

The laser beam used in the blackening unit 220 may be a pulse laser composed of a pulse having an energy of 0.05 to 0.70 nJ. In each case, the processing time is about 1 to 600 seconds, but may be changed according to the size of the bright pixel to be corrected.

The separating unit 230 receives the laser beam generated by the laser generating unit 210 so that the denatured layer 40 in which the color filter 14 is blackened is separated from the upper substrate 12 (step S320). The light blocking layer 60 is cracked inside the pigment due to the modification of the color filter 14 and bubbles are generated so that the organic thin film layer 16 exceeds the limit stress value of the organic thin film layer 16 other than the color filter 14. This explodes to exist as a separation material 50 in the liquid crystal layer 30. Herein, the separation material 50 has adhesiveness in which organic substances are melted in a lump together. Referring to FIG. 6B, the modified layer 40 is separated from the upper substrate 12 and exploded into the separation material 50.

The laser beam used in the separating unit 230 may be a pulse laser consisting of a pulse having an energy of 0.71 to 0.94 nJ. In each case, the processing time is about 1 to 600 seconds, but may be changed according to the size of the bright pixel to be corrected.

The separation layer 40 may be uniformly separated from the upper substrate 12 by scanning a spot of a laser beam during the process of separating the modified layer 40 from the upper substrate 12. See (a) of 7). Alternatively, the shape of the laser beam may be formed to have a shape corresponding to the bright pixel, so that the modified layer 40 may be uniformly separated from the upper substrate 12 by one irradiation (see FIG. 7B). .

The deposition unit 240 receives the laser beam generated by the laser generation unit 210 and the lower substrate corresponding to the bright point pixel portion in which the modified layer 40 separated by the separation unit 230 is lower in the vertical direction. The light blocking layer 60 is formed on the upper pixel surface 26 of the pixel 22 (step S330). Referring to FIG. 6C, a light blocking layer 60 is deposited and solidified on the upper pixel surface 26 corresponding to the bright pixel portion of the lower substrate 22 to completely block light transmission from the backlight. The formed state is shown.

As the organic thin film layer 16 is blown out by bubbles generated from the inside, bubbles introduced into the liquid crystal layer 30 generate an empty space corresponding to the bright pixel portion. Since the ions generated during the blackening step (step S310) by the blackening part 220 or / and the separating step (step S320) by the separating part 230 are areas where the inside of the liquid crystal display panel is sealed, The heat forms a plasma to instantaneously cause the separation material 50 to be chemical vapor deposition (CVD) on the upper pixel surface 26 of the lower substrate 22. As the heat retained by the separation material 50 escapes, the molten organic agglomerates solidify on the upper pixel surface 26 on which the molten organic substance is deposited, thereby solidifying the light blocking layer 60 inside the liquid crystal display panel 1. Will be formed.

The laser beam used in the deposition unit 240 may be a pulse laser consisting of a pulse having an energy of 0.95 to 1.76nJ. In each case, the processing time is about 1 to 600 seconds, but may be changed according to the size of the bright pixel to be corrected.

In the present embodiment, the separation material 50 of the modified layer 40 of the color filter introduced into the liquid crystal layer 30 is deposited on the upper pixel surface 26 of the lower substrate 22 by the deposition unit 240. Existing impurities or ionic materials in the liquid crystal layer 30 as in the related art can be suppressed from adversely affecting the normal pixels adjacent to the bright pixels (for example, high temperature light emission, pixel unevenness, etc.). It can be effective.

Referring to FIG. 8, an optical image of an upper substrate, that is, a surface of a color filter, of a liquid crystal display panel which has been subjected to a blackening step S310, a separation step S320, and a deposition step S330 according to the present embodiment is illustrated. It can be seen that the organic thin film layers protecting the color filter and / or the color filter are separated toward the lower substrate over the entire area irradiated by the laser.

9, when the bright pixels are red pixels, green pixels, and blue pixels, according to the present embodiment, a thick separation material separated from the upper substrate is deposited on the lower substrate to solidify the light coming from the backlight. It can be seen that the light blocking layer is blocked.

10A to 10C, three-dimensional images of light blocking layers 60R, 60G, and 60B deposited on a lower substrate, that is, a TFT substrate, are illustrated when the bright pixels are red, green, and blue pixels, respectively. As compared with the pixel areas 70R, 70G, and 70B, the light blocking layers 60R, 60G, and 60B form a dark ignition layer having a thickness of about 0.5 to 1.5 um.

By forming the light blocking layer 60 on the lower substrate 22 as described above, the distance from the backlight is shortened as compared with the conventional light blocking layer formed on the upper substrate of the liquid crystal display panel, thereby blocking light from the backlight in the vicinity of the backlight. It is possible to increase the light blocking efficiency in the bright pixel area.

In this embodiment, the case in which the liquid crystal display panel 1 has the organic thin film layer 16 that protects the color filter 14, that is, the overcoat layer is illustrated, but the same applies to the liquid crystal display panel without the overcoat layer. It is possible.

FIG. 11A is a schematic diagram and a method of irradiating a laser from a TFT substrate according to an embodiment of the present invention, and FIG. 11B is a schematic diagram and a method of irradiating a laser from a C / F substrate, according to another embodiment of the present invention. FIG. 12 illustrates a result of performing bright spot repair by irradiating a laser on a TFT substrate and a C / F substrate in a liquid crystal display panel operating in an IPS mode. 11A and 11B, the laser beam, the TFT substrate 20, the C / F substrate 10, and the color filter are blackened and separated from the C / F substrate on the TFT substrate according to the present invention. The deposited light blocking layer 60 is shown.

When the laser beam generated by the laser generating unit is irradiated in the present invention, the irradiation direction may be changed according to the operation mode of the liquid crystal display panel.

In liquid crystal display panels operating in twisted nematic (TN) mode and / or vertical alignment (VA) mode, the liquid crystal molecules rotate in a vertical direction to control the amount of backlight light, such that the common electrode and the pixel electrode have a liquid crystal layer interposed therebetween. It is located on different sides. Therefore, both a method of irradiating a laser beam through a TFT substrate (see FIG. 11A) and a method of irradiating a laser beam through a C / F substrate (see FIG. 11B) may be used.

However, in the In-Plane-Switching (IPS) mode, the horizontal and horizontal liquid crystal molecules are rotated in the horizontal direction to control the amount of backlight light, so that both the common electrode and the pixel electrode are located on the TFT substrate surface. Therefore, when the laser beam is irradiated through the TFT substrate, it is difficult to transfer uniform energy to the pigment constituting the color filter due to the common electrode and the pixel electrode. Thus, as shown in FIG. It is desirable to transmit so that the laser beam is illuminated.

The repaired bright pixel area when the laser beam is transmitted through the TFT substrate is shown in FIG. 12A, and the repaired bright pixel area when the laser beam is transmitted through the C / F substrate is shown in FIG. shown in (b). Referring to this, when the laser beam is transmitted through the C / F substrate and the laser beam is transmitted through the TFT substrate where the common electrode and the pixel electrode are positioned, the blocking efficiency of the backlight light is higher than that when the laser beam is irradiated.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention as defined in the appended claims. It will be understood that the invention may be varied and varied without departing from the scope of the invention.

1: liquid crystal display panel 10: C / F substrate
20: TFT substrate 30: liquid crystal layer
12: upper substrate 14: color filter
16: organic thin film layer 18: black matrix
22: lower substrate 24: thin film transistor
110: laser generating unit 120: optical modulator
130: reflection mirror 140: beam expander
150: scanner 160: objective lens unit
170: stage 200: bright spot repair device
210: laser generating unit 220: blackening unit
230: separation unit 240: deposition unit
40: modified layer 50: separation material
60: light blocking layer

Claims (27)

As a method of repairing a bright pixel of a liquid crystal display panel using a laser processing apparatus,
Irradiating a laser beam of a predetermined condition on the color filter of the bright pixel portion of the liquid crystal display panel; The color filter forms a blackened modified layer; The modified layer is separated from the upper substrate; A bright point pixel repair method for forming a light blocking layer that blocks light from a backlight by being deposited on a pixel surface of a lower substrate.
The method of claim 1,
The organic light emitting layer disposed under the color filter is also modified to form the modified layer, characterized in that the bright point repair method of the liquid crystal display panel.
The method of claim 1,
And irradiating a spot of the laser beam uniformly corresponding to the size of the bright pixel or forming and irradiating a shape of the laser beam to correspond to the size of the bright pixel.
The method of claim 1,
The laser beam is a pulse point laser repair method of the liquid crystal display panel, characterized in that the pulse laser consisting of a pulse having an energy of 0.95 to 1.76nJ.
The method of claim 1,
And the laser beam is irradiated through one of the upper substrate and the lower substrate when the liquid crystal display panel operates in one of a TN mode and a VA mode.
The method of claim 1,
The laser beam is irradiated through the upper substrate when the liquid crystal display panel operates in the IPS mode, the bright point repair method of the liquid crystal display panel.
As a method of repairing a bright pixel of a liquid crystal display panel using a laser processing apparatus,
Irradiating a first laser beam of a predetermined condition to a color filter of a bright pixel portion of the liquid crystal display panel to form a modified layer in which the color filter is blackened;
Separating the denatured layer from the upper substrate by a second laser beam in a predetermined condition; And
And a light blocking layer formed by depositing the separated denatured layer on a pixel surface of a lower substrate by a third laser beam under a predetermined condition.
The method of claim 7, wherein
In the forming of the modified layer, the organic thin film layer disposed under the color filter is also modified to form the modified layer.
The method of claim 7, wherein
The separating may be performed by scanning a spot of the second laser beam uniformly corresponding to the size of the bright pixel or by forming and irradiating a shape of the second laser beam to correspond to the size of the bright pixel. Bright point repair method of a liquid crystal display panel.
The method of claim 7, wherein
And the first laser beam, the second laser beam, and the third laser beam in order of high laser output.
The method of claim 10,
Wherein the first laser beam is 0.05 to 0.70 nJ, the second laser beam is 0.71 to 0.94 nJ, and the third laser beam is a pulse laser including pulses having energy of 0.95 to 1.76 nJ. Point of repair repair method.
The method of claim 7, wherein
When the liquid crystal display panel operates in one of a TN mode and a VA mode, the first laser beam, the second laser beam, and the third laser beam are irradiated through one of the upper substrate and the lower substrate. Bright point repair method of a liquid crystal display panel.
The method of claim 7, wherein
And the first laser beam, the second laser beam, and the third laser beam are irradiated through the upper substrate when the liquid crystal display panel is operated in the IPS mode.
As a method of repairing a bright pixel of a liquid crystal display panel using a laser processing apparatus,
Irradiating a laser beam of a predetermined condition on the color filter of the bright pixel portion of the liquid crystal display panel to form a modified layer in which the color filter is blackened;
Separating the modified layer from the upper substrate; And
The separated modified layer is deposited on the pixel surface of the lower substrate to form a light blocking layer comprising a bright point repair method of a liquid crystal display panel.
15. The method of claim 14,
In the forming of the modified layer, the organic thin film layer disposed under the color filter is also modified to form the modified layer.
15. The method of claim 14,
The separating step may be performed by scanning a spot of the laser beam uniformly corresponding to the size of the bright pixel or by forming and irradiating a shape of the laser beam to correspond to the size of the bright pixel. How to repair the bright spot of the panel.
15. The method of claim 14,
The laser beam is a pulse point laser repair method of the liquid crystal display panel, characterized in that the pulse laser consisting of a pulse having an energy of 0.95 to 1.76nJ.
15. The method of claim 14,
And the laser beam is irradiated through one of the upper substrate and the lower substrate when the liquid crystal display panel operates in one of a TN mode and a VA mode.
15. The method of claim 14,
The laser beam is irradiated through the upper substrate when the liquid crystal display panel operates in the IPS mode, the bright point repair method of the liquid crystal display panel.
As a bright spot repair apparatus which repairs the bright spot defect of a liquid crystal display panel,
A laser generator for generating a laser beam in a predetermined condition;
A blackening unit that receives the laser beam and irradiates a color filter of a bright pixel portion to form a modified layer in which the color filter is blackened;
A separation unit for receiving the laser beam and irradiating the modified layer to separate the modified layer from the upper substrate; And
And a deposition unit for receiving the laser beam and irradiating the separated modified layer to form a light blocking layer in which the separated modified layer is deposited on a pixel surface of a lower substrate.
21. The method of claim 20,
The blackening unit is a bright point repair device, characterized in that to modify the organic thin film layer located below the color filter.
21. The method of claim 20,
And the separating unit irradiates a spot of the laser beam uniformly corresponding to the size of the bright pixel or to form and irradiate a shape of the laser beam so as to correspond to the size of the bright pixel.
21. The method of claim 20,
The laser generating unit is a bright point repair device, characterized in that the laser beam used in the blackening unit, the separation unit, the deposition unit sequentially have a high laser output.
21. The method of claim 20,
The laser generating unit is a point repair device characterized in that the laser beam is composed of a pulse having an energy of 0.95 to 1.76nJ.
21. The method of claim 20,
And the laser beam is irradiated through one of the upper substrate and the lower substrate when the liquid crystal display panel is operated in one of a TN mode and a VA mode.
21. The method of claim 20,
And the laser beam is irradiated through the upper substrate when the liquid crystal display panel operates in the IPS mode.
A liquid crystal display panel in which a bright point defect is repaired by a laser processing apparatus,
A liquid crystal display panel, in which a color filter corresponding to a bright pixel portion is blackened by a laser beam under a predetermined condition, separated from an upper substrate, and deposited on a pixel surface of a lower substrate to form a light blocking layer.

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