KR100847293B1 - Method and apparatus for inspecting external appearance of liquid crystal display panel - Google Patents

Abstract

A method and an apparatus for inspecting the external appearance of an LCD(Liquid Crystal Display) panel are provided to perform the inspection by means of different polarizing films without a replacing work. A frame(100) having an inside space comprises the opened upper side and lower side. A back light unit is installed in the inner space of the frame. First and second stages are installed to be symmetric respectively to the upper and the lower side of the frame with the back light unit as the center. A rotation member(300) inverts the frame for placing the LCD panel selectively on one of the first and the second stages. The first polarization plate is installed at one side of the first optical module facing to the first stage. A second polarization plate having the different property from the first polarization plate is installed at one side of a second optical module facing to the second stage. The light supplied to the first stage direction is different from the light supplied to the second stage direction.

Description

Apparatus and method for inspecting the appearance of a liquid crystal display panel {Method and Apparatus For Inspecting External Appearance of Liquid Crystal Display Panel}

1 is a perspective view schematically showing an appearance inspection apparatus of a substrate to be processed according to an embodiment of the present invention.

2 and 3 are a plan view and a side cross-sectional view schematically showing an appearance inspection apparatus of a substrate to be processed according to an embodiment of the present invention.

4 is a diagram illustrating a modified example of the first and second optical modules.

5A to 5G are diagrams for explaining a step of inspecting an appearance of a substrate.

* Description of the symbols for the main parts of the drawings *

100: frame

200: backlight unit

300: rotating member

400a: Stage 1

400b: second stage

The present invention relates to an inspection apparatus for a liquid crystal display panel, and more particularly, to an inspection apparatus for a liquid crystal display panel for visual inspection.

As the information society develops, the demand for display devices is increasing in various forms.In recent years, liquid crystal display (LCD), plasma display panel (PDP), electro luminescent display (ELD), and vacuum fluorescent display (VFD) have been developed. Various flat panel display devices have been studied, and some of them are already used as display devices in various devices.

Among them, LCD is the most widely used as a substitute for CRT (Cathode Ray Tube) for the use of mobile image display device because of the excellent image quality, light weight, thinness, and low power consumption, and mobile type such as monitor of notebook computer. In addition, it is being developed in various ways such as a television for receiving and displaying a broadcast signal, a monitor of a computer.

As described above, although various technical advances have been made in order for the liquid crystal display device to serve as a screen display device in various fields, the task of improving the image quality as the screen display device has many advantages and disadvantages. Therefore, in order to use a liquid crystal display device in various parts as a general screen display device, development of high quality images such as high brightness and large area while maintaining the characteristics of light weight, thinness, and low power consumption is at stake. Can be.

The liquid crystal display may be classified into a liquid crystal display panel displaying an image and a driving unit for applying a driving signal to the liquid crystal display panel, wherein the liquid crystal display panel includes a first and second substrates having a space and are bonded to each other; It consists of a liquid crystal layer injected between said first and second substrates.

The liquid crystal display panel performs an external appearance inspection of the liquid crystal display panel before the module process of additionally assembling the backlight and the driving circuit. The external appearance of the liquid crystal display panel is inspected using a polarizing film having a different characteristic as necessary. To this end, conventionally, after preparing two polarizing modules equipped with different polarizing films, the situation is selectively used.

However, the replacement of the polarizing module has the following problems. First, in order to replace the polarizing module, at least two workers are required by manpower because two workers must hold and replace the polarizing module at both sides. In addition, after replacing the polarizing module, a time loss that requires a new setup also occurs.

An object of the present invention is to provide an appearance inspection equipment of the liquid crystal display panel which can be inspected using different polarizing films without replacement work.

It is also an object of the present invention to provide an external appearance inspection equipment of a liquid crystal display panel which can inspect two liquid crystal display panels having different characteristics.

In addition, an object of the present invention is to provide an appearance inspection equipment of the liquid crystal display panel that can improve the inspection throughput.

In order to achieve the above technical problem, an apparatus for inspecting an appearance of a liquid crystal display panel according to an embodiment of the present invention has an internal space, and includes a frame having an upper surface and a lower surface; A backlight unit installed in the inner space of the frame; First and second stages symmetrically disposed on an upper surface and a lower surface of the frame around the backlight unit and on which a liquid crystal display panel is disposed; And a rotating member for inverting the frame so that the liquid crystal display panel can be selectively placed on any one of the first stage and the second stage.

The backlight unit may include: a first optical module having a first polarizing plate installed on one surface facing the first stage; And a second optical module installed on one surface facing the second stage and having a second polarizing plate having a different property from that of the first polarizing plate.

In example embodiments, the backlight unit may include a first polarizing plate disposed on one surface facing the first stage, and a second polarizing plate disposed on one surface facing the second stage and having a different property from that of the first polarizing plate. It includes more.

In one embodiment, the first polarizing plate passes through the light of the P wave (longwave) component, the second polarizing plate passes through the light of the S wave (transverse wave) component.

In one embodiment, the backlight unit comprises a light source; And a reflection shade for providing the light of the light source in the first stage direction or the second stage direction.

In one embodiment, the reflector is rotated according to the rotation angle of the frame.

In one embodiment, the backlight unit further comprises a support plate on which both ends of the reflection shade is installed; The support plate is formed with a guide groove for guiding the reflector to rotate in accordance with the rotation angle.

The first stage and the second stage may further include a plurality of support pins for supporting the bottom of the liquid crystal display panel, and clamps for fixing the edges of the liquid crystal display panel supported by the support pins.

In another aspect, an apparatus for inspecting appearance of a liquid crystal display panel according to the present invention may include a backlight unit having a light source for irradiating light to the liquid crystal display panel; A first stage positioned at one side of the backlight unit and having a liquid crystal display panel; A second stage positioned in the other direction of the backlight unit opposite to the first stage and on which a liquid crystal display panel is placed; A first optical module disposed between the first stage and the backlight unit and having a first polarizing plate; And a second optical module disposed between the second stage and the light source and having a second polarizing plate.

The apparatus may include: a frame in which the backlight unit and the first and second stages are fixedly installed; It further comprises a rotating member for rotating the frame.

In an embodiment, the backlight unit may include: a first optical module installed on one surface facing the first stage and having a first polarizing plate through which light of a P wave component is passed; And a second optical module installed on one surface facing the second stage and having a second polarizing plate through which light of an S wave component passes.

In one embodiment, the first optical module and the second optical module further comprises a diffusion plate for diffusing light, and a reinforcing plate for supporting the diffusion plate; The tempered plate is shaped of tempered glass in the form of a bar.

In one embodiment, the first stage and the second stage a plurality of support bars across the open surface of the frame; A plurality of support pins installed at the support bars at predetermined intervals to support a bottom surface of the liquid crystal display panel; And clamps fixing an edge of the liquid crystal display panel supported by the support pins.

According to an aspect of the present invention, there is provided a method of inspecting an external appearance of a liquid crystal display panel, the method comprising: performing a primary appearance inspection by providing light through a backlight unit in a state where the liquid crystal display panel is placed on a first stage; Inverting the liquid crystal display panel so that the liquid crystal display panel can be placed on a second stage opposite to the first stage with the backlight unit interposed therebetween; And providing a light through the backlight unit in a state where the liquid crystal display panel is placed on the second stage, and performing a second appearance inspection.

In one embodiment, the light provided to the liquid crystal display panel in the first inspection step and the light provided to the liquid crystal display panel in the second inspection step are different from each other.

In one embodiment, the light provided to the liquid crystal display panel placed on the first stage in the first inspection step is provided after passing through the first polarizing plate of the backlight unit, the liquid crystal placed on the second stage in the second inspection step Light provided to the display panel is provided after passing through the second polarizing plate of the backlight unit.

In one embodiment, the first polarizing plate passes through the light of the P wave (longwave) component, the second polarizing plate passes through the light of the S wave (transverse wave) component.

For example, embodiments of the present invention may be modified in various forms, and the scope of the present invention should not be construed as being limited by the embodiments described below. This embodiment is provided to more completely explain the present invention to those skilled in the art. Accordingly, the shape of the elements in the drawings and the like are exaggerated to emphasize a clearer description. In understanding the drawings, it should be noted that like parts are intended to be represented by the same reference numerals as much as possible. And detailed description of known functions and configurations that are determined to unnecessarily obscure the subject matter of the present invention is omitted.

(Example)

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings to describe the apparatus and method for inspecting the appearance of a substrate for a liquid crystal display panel according to the present invention. In addition, in the drawings, the same reference numerals are denoted together for components that perform the same function.

 According to the present invention, a unit panel is formed by joining two substrates so that liquid crystals are interposed therebetween, and then, before assembling a backlight and a driving circuit, the exterior of the bonded panel is inspected by inspecting the appearance of the unit panel, and is there a scratch on the appearance? The present invention relates to an appearance inspection apparatus capable of inspecting whether there are foreign substances in the liquid crystal layer by selectively using two polarizing plates having different properties.

Here, the substrate 20 is a large substrate for a liquid crystal display panel having at least one unit liquid crystal display panel formed thereon, and the unit liquid crystal display panel is a pattern formed on the upper glass substrate, the lower glass substrate, and the lower glass substrate on which the pattern is formed. And a liquid crystal filled between the spacer and the sealing material applied to correspond to the upper glass substrate and the lower glass substrate to correspond to each pattern.

1 is a perspective view schematically showing an appearance inspection apparatus of a substrate according to an embodiment of the present invention, FIG. 2 is a plan view schematically illustrating an appearance inspection apparatus of a substrate according to an embodiment of the present invention, and FIG. 3. Is a side cross-sectional view of line aa shown in FIG. 2.

1 to 3, the apparatus 10 for inspecting appearance of a substrate to be processed may include a frame 100, a backlight unit 200, a rotating member 300, and a first stage 400a and a second stage. 400b. As shown in FIG. 3, in the appearance inspection apparatus 10 of the present invention, the stages 400a and 400b on which the processing target substrate 20 is placed are disposed on both sides, and the frame 100 is formed using polarizing plates having different characteristics. It has a special effect of selectively inspecting two to-be-processed substrates or inspecting one to-be-processed substrate using different polarizing plates while inverting 180 degrees.

Looking at each configuration in detail as follows.

The frame 100 has openings 112 larger than the substrate to be processed on the first and second surfaces 110a and 110b corresponding to the upper and lower surfaces, respectively, and the rear surface of the substrate 20 in the inner space. The backlight unit 200 which is turned on to illuminate is installed. The frame 100 is connected to the rotating shaft 310 so that both sides 120 are rotatable, and the rotating member 300 is connected to one of the rotating shafts.

The frame 100 is rotated by the rotating member 300 so that the transport robot may bring the substrate 20 to the first stage 400a or may carry the substrate 20 from the first stage 400a. The first stage 400a is rotated to be located above. In addition, the frame 100 may include the rotating member 300 so that the transport robot may bring the substrate 20 to the second stage 400b or may carry the substrate 20 from the second stage 400b. The second stage 400b is rotated to be positioned above. In the inspection step, the operator may be rotated inclined by the rotating member 300 so that the operator can easily observe the substrate 20 from various angles.

The backlight unit 200 is installed in the internal space of the frame 100. The backlight unit 200 includes a plurality of high brightness fluorescent lamps 210, reflection shades 220, a first optical module 230a, and a second optical module 230b.

The fluorescent lamps 210 are installed on the center line of rotation of the frame 100. The reflector 220 has an arch shape for reflecting light of the fluorescent lamp 210 so that the light emitted from the fluorescent lamp 210 is incident on the substrate 20 to be processed. The reflection shade 220 is provided so that the guide pins 222 at both ends are rotatably supported by the support plate 226. The support plate 226 is formed with a guide groove 228 into which the guide pins 222 of both ends of the reflection shade 220 are fitted within a predetermined radius of rotation. The reflector 220 is lowered by the weight along the guide groove 228 to provide the light of the fluorescent lamp 210 to the first stage 400a or the second stage 400b according to the rotation of the frame 100. Is rotated in the direction. In particular, the reflection shade 220 is configured to form a weight 224 below the center to facilitate rotation by its own weight.

For example, the reflector 220 is temporarily positioned upward when the frame 100 is rotated, but then falls downward along the guide groove 228 by its own weight, so that the reflector 220 can always reflect light upward. It is home. In the present embodiment, the reflection shade 220 is configured to rotate along the guide groove 228 by its own weight, but if necessary, the rotation of the reflection shade 220 is not rotated by its own weight, but the frame 100 using the driving device. According to the rotation of the reflector 220 may be implemented to rotate.

The first optical module 230a is disposed between the first stage 400a and the fluorescent lamp 210, and the second optical module 230b is disposed between the second stage 400b and the fluorescent lamp 210. That is, the first optical module 230a and the second optical module 230b are symmetrically installed with the fluorescent lamp 210 interposed therebetween. The first optical module 230a has a structure in which the reinforcing plate 232, the diffusion plate 234, and the first polarizing plate 236 are stacked in a multilayer. In addition, the second optical module 230b has a structure in which the reinforcing plate 232, the diffusion plate 234, and the second polarizing plate 238 are stacked in multiple layers.

The reinforcing plate 232 of the first optical module 230a and the second optical module 230b is made of a glass material supporting the diffusion plate 234. When the substrate 20 is a large area, a problem may arise in that the central portion of the reinforcing plate 232 is bent by its own weight. In order to solve this problem, as shown in Figure 4, it may be formed of tempered glass 232a of the long bar shape in the longitudinal direction of the fluorescent lamp 210. Bar-shaped tempered glass (232a) may be arranged spaced apart from each other or may be arranged to be connected to each other. The diffusion plate 234 of the first optical module 230a and the second optical module 230b is made of an acrylic plate. For example, the first optical module 230a and the second optical module 230b may further include optical sheets such as a prism sheet.

The first polarizing plate 236 of the first optical module 230a and the second polarizing plate 238 of the second optical module 230b use different properties. That is, light passing through the first optical module 230a to the first stage 400a and light passing through the second optical module 230b to the second stage 400b have different properties from each other. Preferably, the first polarizing plate 236 has a polarizing film structure through which light of a P wave (longwave) component passes, and the second polarizing plate 238 has a polarizing film structure through which light of a S wave component is transmitted. .

The first stage 400a is installed on the first surface 110a of the frame 100, and the second stage 400b is disposed on the second surface 110b of the frame 100 opposite to the first stage 400a. Is installed. The first stage 400a and the second stage 400b are provided with a plurality of support bars 410 across the open surface of the frame 100 and the support bars 410 at predetermined intervals to be processed. A plurality of support pins 420 supporting the bottom surface of the 20 and the edges of the substrate 20 supported by the support pins 420 are fixed to rotate the frame 100 to be processed. The clamps 430 to stably hold and the alignment 440 for aligning the position of the substrate 20 to be processed. In the present invention, the substrate 20 is supported by the plurality of support pins 420, thereby minimizing deflection.

The substrate 20 to be processed is placed on the support pins 420 of the first stage 400a or the second stage 400b by the transfer robot. The edge of the substrate 20 is fixed by the clamps 430. Here, the fixing method of the substrate 20 is a commercially available method commonly used in the liquid crystal display panel inspection apparatus, and detailed illustration and description thereof will be omitted.

5A to 5G, the appearance inspection process of the substrate to be processed will be described step by step.

As shown in FIG. 5A, the substrate 20 to be processed is loaded into the first stage 400a by an external transfer robot 700. When the substrate 20 is fixed by the clamp 430 while being supported by the support pins 420, the substrate 20 is inclined to the rotation angle for inspection by the rotating member 300 (FIG. 5B). In this case, the backlight unit 200 provides light to the substrate 20 through the first optical module 230a. In this state, the operator directly holds a separate polarizing plate 800 having a size of a predetermined size in his hand. The primary appearance inspection of the substrate 20 to be processed from various angles. On the other hand, after completing the primary appearance inspection, the frame 100 is rotated back to its original state (FIG. 5C). After the first inspection, the substrate 20 to be processed is temporarily unloaded from the first stage 400a by the transfer robot 700 (FIG. 5D), and the frame 100 is rotated 180 degrees by the rotating member 300. Inverted (FIG. 5E). When the substrate 20 to be processed is placed on the second stage 400b again by the transfer robot 700 (FIG. 5F) and fixed by the clamp 430, with the second stage 400b facing upwards. The rotating member 300 is tilted at an angle of rotation for inspection (FIG. 5G). The backlight unit 200 provides light to the substrate 20 through the second optical module 230b. In this state, the operator directly holds a separate polarizing plate 800 having a size of a predetermined standard in his hand and performs secondary appearance inspection on the appearance of the substrate 20 to be processed at various angles.

In this embodiment, it was described that one test substrate is subjected to two inspections using different polarizing plates on the first stage and the second stage, respectively. However, if necessary, it is a matter of course that the substrates having different properties can be selectively inspected on the first stage and the second stage, respectively.

As described above, the apparatus for inspecting the external appearance of the substrate to be processed may automatically perform appearance inspection using different polarizing plates in an in-line state, and waste time due to unnecessary replacement of the polarizing plate in the conventional external inspection. By preventing the inconvenience of the work, there is an advantage that can expect to improve the throughput (Throughput).

Apparatus for inspecting the appearance of the substrate for a liquid crystal display panel according to the present invention may be variously modified and may take various forms. It is to be understood, however, that the present invention is not limited to the specific forms referred to in the above description, but rather includes all modifications, equivalents and substitutions within the spirit and scope of the invention as defined by the appended claims. It should be understood to do.

As described above, the present invention can automatically perform appearance inspection using different polarizing plates in an in-line state, thereby avoiding time wastage and inconvenience of work due to unnecessary replacement of polarizing plates in conventional appearance inspection. By preventing, there is an advantage that can expect to improve the throughput (Throughput).

Claims (17)

In the appearance inspection apparatus of the liquid crystal display panel: A frame having an inner space and having an open top and bottom surfaces; A backlight unit installed in the inner space of the frame; First and second stages symmetrically disposed on an upper surface and a lower surface of the frame around the backlight unit and on which a liquid crystal display panel is disposed; And And a rotating member which inverts the frame so that the liquid crystal display panel can be selectively placed on any one of the first stage and the second stage. The method of claim 1, The backlight unit A first optical module having a first polarizing plate installed on one surface facing the first stage; And A second optical module installed on one surface facing the second stage and having a second polarizing plate having a property different from that of the first polarizing plate, the light provided in the first stage direction and the second stage direction; Apparatus for inspecting the appearance of a liquid crystal display panel, wherein light provided is different. The method of claim 1, The backlight unit A first polarizing plate installed on one surface facing the first stage; A second polarizing plate disposed on one surface facing the second stage and having a property different from that of the first polarizing plate, wherein the light provided in the first stage direction and the light provided in the second stage direction are different from each other; Appearance inspection apparatus of the liquid crystal display panel characterized by. The method according to claim 2 or 3, And the first polarizing plate passes light having a P wave component, and the second polarizing plate passes light having a S wave component. The method according to claim 1 or 2, The backlight unit Light source; And And a reflection shade for providing the light of the light source to the first stage direction or the second stage direction. The method of claim 5, Appearance inspection apparatus of the liquid crystal display panel, characterized in that the reflection shade is rotated according to the rotation angle. The method of claim 5, The backlight unit Further comprising a support plate on which both ends of the reflection shade is installed; And a guide groove for guiding the reflection shade to rotate according to a rotation angle. The method according to any one of claims 1 to 3, The first stage and the second stage A plurality of support pins for supporting the bottom of the liquid crystal display panel, Apparatus for inspecting the appearance of a liquid crystal display panel further comprising clamps for fixing the edge of the liquid crystal display panel supported by the support pins. In the appearance inspection apparatus of the liquid crystal display panel: A backlight unit having a light source for irradiating light to the liquid crystal display panel; A first stage positioned at one side of the backlight unit and having a liquid crystal display panel; A second stage positioned in the other direction of the backlight unit opposite to the first stage and on which a liquid crystal display panel is placed; A first optical module disposed between the first stage and the backlight unit and having a first polarizing plate; And And a second optical module disposed between the second stage and the light source, the second optical module having a second polarizing plate. The method of claim 9, The device is A frame in which the backlight unit and the first and second stages are fixedly installed; Apparatus for inspecting the appearance of a liquid crystal display panel further comprising a rotating member for rotating the frame. The method of claim 9 or 10, The backlight unit A first optical module installed on one surface facing the first stage and having a first polarizing plate through which light of a P wave component passes; And And a second optical module installed on one surface facing the second stage and having a second polarizing plate through which light of an S-wave component passes. The light provided in the first stage direction and provided in the second stage direction. Apparatus for inspecting appearance of a liquid crystal display panel, characterized in that light is different. The method of claim 11, The first optical module and the second optical module further comprises a diffusion plate for diffusing light and a reinforcing plate for supporting the diffusion plate; And the tempered plate is formed of tempered glass having a bar shape. The method of claim 9 or 10, The first stage and the second stage A plurality of support bars across the open side of the frame; A plurality of support pins installed at the support bars at predetermined intervals to support a bottom surface of the liquid crystal display panel; And Apparatus for inspecting the appearance of the liquid crystal display panel comprising clamps for fixing the edge of the liquid crystal display panel supported by the support pins. In the external inspection method of the liquid crystal display panel: Performing a first appearance inspection by providing light through the backlight unit while the liquid crystal display panel is placed on the first stage; Inverting the liquid crystal display panel so that the liquid crystal display panel can be placed on a second stage opposite to the first stage with the backlight unit interposed therebetween; And providing a light through a backlight unit in a state where the liquid crystal display panel is placed on the second stage, and performing a second external appearance inspection. The method of claim 14, The light provided to the liquid crystal display panel in the first inspection step and the light provided to the liquid crystal display panel in the second inspection step are different from each other. The method of claim 14, Light provided to the liquid crystal display panel placed on the first stage in the first inspection step is provided after passing through the first polarizing plate of the backlight unit. And the light provided to the liquid crystal display panel placed on the second stage in the second inspection step is provided after passing through the second polarizing plate of the backlight unit. The method of claim 16, And the first polarizing plate passes light of a P wave component, and the second polarizing plate passes light of a S wave component.

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