JP2003075792A - Tool for inspecting liquid crystal panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tool for inspecting a liquid crystal panel hardly causing oversights of defects or the like in a dynamic display operating inspection. SOLUTION: The tool for inspecting the liquid crystal panel is provided with a holding plate 2 for freely attachable and detachably holding a liquid crystal panel 1, which holding plate 2 consists of a frame body with an opening 2a to bring in light from a backlight 4 to the display part of the liquid crystal panel 1 and has a fitting part 12 which is a recession with a specified depth arranged downward on the circumferential part of the opening 2a of the holding plate 2 and accepts and mounts the circumference of a diffusion plate 9, a lens sheet 10, a polarizing plate 11, etc., stacked on the downside of the liquid crystal panel 1 to the fitting part 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal panel inspection jig applied to a liquid crystal panel lighting inspection or the like.

[0002]

2. Description of the Related Art A liquid crystal panel includes a large number of pixel electrodes arranged in rows and columns, and a liquid crystal layer that modulates light according to a voltage applied to the pixel electrodes. In recent years, with the improvement in the quality of such liquid crystal panels, a method has been used in which a switching element is added to each picture element electrode and a video signal is applied to the picture element electrode via the switching element. However, since the process of forming such a switching element is complicated, problems such as defective pixels, disconnection or short circuit of scanning lines and signal lines, and defective switching elements have become problems.

Further, the liquid crystal display device includes a TFT substrate and a CF.
By forming a substrate, pasting these two substrates together, dividing them, and injecting a liquid crystal in order, then by incorporating a polarizing plate, a driver circuit for driving the liquid crystal panel, a mounting member such as a backlight and a bezel, Can be assembled. Since these members are expensive, it is necessary to detect the above defects before mounting and select good products and defective products.

Conventionally, as an inspection before incorporating the mounting member, as shown in FIGS. 13 and 14, a liquid crystal panel 20 is provided.
A simple inspection jig is used in which a holding plate 21 for holding the liquid crystal panel and a mounting plate 22 having a testing signal input unit for inputting a drive signal to the liquid crystal panel 20 are combined. This inspection jig is used for the liquid crystal panel 2
It is installed on a backlight 24 having a polarizing plate 23 attached to its light emitting surface so that light can enter 0.
The inspection is carried out by placing a polarizing plate 25 having a polarization angle orthogonal to that of the polarizing plate 23 on the second plate 2.

When using such an inspection jig, the attachment plate 2 to which the above-mentioned inspection signal input unit is attached
Due to the thickness of 2, the shadow of the mounting plate 22 enters the space 26 between the liquid crystal panel 20 and the upper polarizing plate 25 at the time of inspection, so that an erroneous determination or the like of the inspection operator occurs.

As a means for solving such a problem, a technique disclosed in Japanese Patent Laid-Open No. 10-54967 has been proposed, particularly as a technique for thinning the inspection signal input unit. Further, the technique disclosed in Japanese Patent Laid-Open No. 10-20326 has been proposed as a technique capable of inspecting in a state closer to a module.

As shown in FIG. 14, the liquid crystal panel 20
A space 27 is created between the lower polarizing plate 23 and the lower polarizing plate 23, and as a result, when the liquid crystal panel 20 is inspected, scratches, dust, etc. of the lower polarizing plate 23 and the backlight 24 can be seen through the liquid crystal panel. However, it has led to erroneous detection such as oversight of small pixel defects and flaws in the CF substrate. In addition, ambient light and the like are reflected by the upper polarizing plate, and the inspection operator overlooks defects.

[0008]

In the inspection using a conventional jig for inspecting a liquid crystal panel, particularly, the jig disclosed in the above-mentioned Japanese Patent Laid-Open No. 10-54967, the polarized light disposed above and below the liquid crystal panel is polarized. Since there is a space between the plates to hold the holding plate of the liquid crystal panel and the mounting plate of the inspection signal input unit, when inspecting the liquid crystal panel, it passes over the liquid crystal panel and scratches and dust on the lower polarizing plate and backlight, and dust. Etc. are visible, which leads to erroneous detection of small pixel defects and oversight of flaws in the CF substrate. In addition, ambient light and the like are reflected by the upper polarizing plate, and the inspection operator may overlook the defect.
Detection failure was found in the inspection in the module state in which the mounting members were assembled.

In order to solve such a problem, a diffusing plate, a lens sheet, and a polarizing plate are directly installed on the lower side of the liquid crystal panel without providing a space below the liquid crystal panel to show a gap passing through the liquid crystal panel. It is also necessary to use a polarizing plate including an antireflection layer as the upper polarizing plate so that ambient light is not reflected.

In the technique disclosed in Japanese Unexamined Patent Publication No. 10-20326, an electric signal is input using a leaf spring and a rubber connector so that the liquid crystal panel can fit within the thickness of the liquid crystal panel. As the size and size increase, the leaf springs and rubber connectors have severe thickness restrictions, making it difficult to maintain the pressure required to connect the terminals of the liquid crystal panel. Further, in the above-mentioned conventional technique, a plate having the inspection signal input unit attached is provided on the upper side of the inspection jig, and the liquid crystal panel is attached / detached by opening / closing this plate. There was a fear of damage. It is an object of the present invention to provide a jig for inspecting a liquid crystal panel that solves these problems.

[0011]

According to the present invention, a jig for inspecting a liquid crystal panel comprises a frame body having an opening for taking in light from a backlight and detachably holding the liquid crystal panel. The holding plate is provided, and a recess having a predetermined depth is provided downward in the peripheral portion of the opening of the holding plate to form a fitting portion, and the fitting portion is laminated and arranged on the lower surface of the liquid crystal panel. The peripheral portions of the polarizing plate, the lens sheet, the diffusion plate, etc. are fitted and placed.

According to this structure, since the polarizing plate, the lens sheet, the diffusing plate and the like are laminated on the lower surface of the liquid crystal panel held by the holding plate, the bending of these laminated bodies including the liquid crystal panel is reduced. Especially, by using the lens sheet and the diffusion plate together, the efficiency of the backlight can be improved and the inspection accuracy of the liquid crystal panel can be improved. Moreover, since there is no gap between the liquid crystal panel and the polarizing plate, there is an erroneous detection at the time of inspecting the liquid crystal panel, which is caused by the space formed between the liquid crystal panel and the lower polarizing plate in the prior art, that is, when the liquid crystal panel is inspected. It is possible to see scratches, dust, and the like of the lower polarizing plate and the backlight after passing through the panel, and eliminate erroneous detection such as overlooking small pixel defects and scratches in the CF substrate.

Further, in the liquid crystal panel inspection jig of the present invention, a vertically moving push-up pin is provided at the edge of the opening of the holding plate, and the push-up pin allows the liquid crystal panel to float above the holding plate. There is. With this configuration, when the liquid crystal panel is removed from the plate of the present invention, the liquid crystal panel can be easily lifted from the holding plate by moving the push-up pin upward, and the liquid crystal panel can be easily removed.

Further, in the inspection jig for a liquid crystal panel of the present invention, a vertically moving push-up pin is provided at the edge of the opening of the holding plate, and the push-up pin is provided at a position opposite to the position where the push-up pin is provided. A positioning member for positioning the liquid crystal panel is provided on the holding plate, and the liquid crystal panel is lifted from the holding plate by the push-up pin with the positioning member as a fulcrum. According to this structure, when the liquid crystal panel is removed from the plate of the present invention, the liquid crystal panel can be easily lifted from the holding plate by moving the push-up pin upward with the positioning member as a fulcrum, and the liquid crystal panel can be easily removed. Can be done.

Further, the liquid crystal panel inspection jig of the present invention holds the inspection signal input unit for inputting the inspection signal only to the side of the liquid crystal panel where the inspection signal needs to be input. It is arranged on the plate. According to this configuration, the inspection signal input unit for inputting the inspection signal only on the side of the liquid crystal panel where the inspection signal needs to be input is arranged on the holding plate. The number of points can be reduced as much as possible.

Further, the jig for inspecting a liquid crystal panel of the present invention is the jig for inspecting a liquid crystal panel according to any one of claims 1 to 4, wherein the upper polarizing plate is closely attached to the upper surface of the liquid crystal panel. Is equipped with. With this configuration, the upper polarizing plate can be easily attached to the upper surface of the liquid crystal panel and the upper polarizing plate can be held without slipping off.

Further, the liquid crystal panel inspecting jig of the present invention is supported by a supporting arm erected on the substrate plate so as to be capable of displacing the inclination angle by the backlight portion. With this configuration, the tilt angle can be changed on the substrate plate with the liquid crystal panel attached to the inspection jig, and the liquid crystal panel can be easily inspected.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. 1 and 2 are a schematic plan view and a schematic side view showing a state in which a liquid crystal panel is inspected using an inspection jig for a liquid crystal panel according to an embodiment of the present invention. As is clear from these figures, FIG. LCD panel inspection jig
A holding plate 2 made of a quadrilateral frame for holding the liquid crystal panel 1 in the center, a test signal input unit 3 attached to the holding plate 2 and electrically connected to two sides of the liquid crystal panel 1, A backlight 4, which is attached to the back surface of the holding plate 2 for making light incident on the liquid crystal panel 1, and irradiates the display section of the liquid crystal panel with light emitted through an opening 2a provided in the central portion of the holding plate 2. A backlight holding frame 5 that surrounds the backlight 4 and a support arm 7 that is erected on the substrate plate 6 and that supports the entire body through the backlight holding frame 5 so as to displace the tilt angle back and forth. There is.

As shown in FIG. 3, the holding plate 2 has a positioning member 8 for positioning the inspection signal input unit 3 and the liquid crystal panel 1 on the holding plate 2, and a backlight light emitted from the backlight 4 to be uniform. A diffusing plate 9, a lens sheet 10 for aligning backlight light in parallel, and a recessed fitting portion 12 for fitting the peripheral edges of a polarizing plate 11, and urethane rubber fixed to the polarizing plate 11 side and fixed with screws or the like. As a result, the polarizing plate pressing plate 13 for pressing the polarizing plate 11 and the push-up pin 14 for vertically moving the liquid crystal panel 1 from the holding plate 2 are provided at the edge of the opening 2a of the holding plate 2. It has and.

The fitting portion 12 is processed to a depth of the same size as the combined thickness of the diffusion plate 9, the lens sheet 10 and the polarizing plate 11, and is fitted into the fitting portion 12 at the time of inspection. Diffusing plate 9, lens sheet 10 and polarizing plate 1
1 is in contact with the lower side of the liquid crystal panel 1 (TFT substrate side). At this time, the diffusing plate 9 should preferably have a thickness of 0.5 mm to 1.0 mm in consideration of the bending and the transmittance of the diffusing plate itself. As a result, it is possible to eliminate the space between the liquid crystal panel and the polarizing plate unlike the conventional inspection jig.

The polarizing plate pressing plate 1 for preventing the diffusion plate 9, the lens sheet 10 and the polarizing plate 11 from being displaced.
3 (FIG. 1) is arranged so as not to come into contact with the liquid crystal panel 1, the diffusion plate 9 for the liquid crystal panel 1 to be inspected,
Since the outer dimensions of the lens sheet 10 and the polarizing plate 11 are formed to be larger than the opening size of the holding plate 2 and attached to the holding plate 2, the liquid crystal panel 1 is in a state of being in close contact with the polarizing plate 11. Has become. Therefore, according to such a configuration, when the liquid crystal panel 1 is detached from the inspection jig, a worker needs a gap for engaging a fingertip or a tool in order to lift the liquid crystal panel 1.

As described above, in order to lift the liquid crystal panel 1 from the polarizing plate 11, the holding panel 2 is used in this embodiment.
It is equipped with a push-up pin 14. That is, the push-up pin 14 is arranged on the side of the inspection signal input unit 3 where the contact area with the liquid crystal panel 1 can be easily obtained. The push-up pin 14 is at the same height as the back surface of the liquid crystal panel 1 during the inspection as shown in FIG. 3, and when the liquid crystal panel 1 is detached after the inspection, Using the power of the cylinder, the liquid crystal panel 1 is lifted up until there is a space (about 20 mm) between the liquid crystal panel 1 and the polarizing plate 11 where an operator can put his / her hand.

As shown in FIG. 1, when the inspection jig for the liquid crystal panel 1 includes the inspection signal input unit 3 on the upper edge and the left edge of the liquid crystal panel 1, the upper edge side of the liquid crystal panel 1 A push-up pin 14 is provided on the positioning member 8 when removing the liquid crystal panel, as shown in FIG.
Is a fulcrum and pushes up the pin 14 above the liquid crystal panel 1.
A gap is formed due to the rise of the liquid crystal panel, and the liquid crystal panel 1 can be easily removed from the upper edge thereof by utilizing this gap.

On the other hand, when the liquid crystal panel inspection jig of the present invention is provided with the inspection signal input unit 3 at the lower edge and the left edge of the liquid crystal panel 1, the positioning member 8 and the push-up pin 14 are provided. As shown in FIG. 5, when the liquid crystal panel 1 is integrally provided, a gap is formed under the liquid crystal panel 1 together with the positioning member 8 by the rise of the push-up pin 14, and the liquid crystal can be easily utilized by utilizing this gap. Panel 1
Can be removed from its lower edge.

Next, the inspection signal input unit 3 for inputting an electric signal required for inspection to the liquid crystal panel 1 will be described. The inspection signal input unit 3 is arranged in the holding frame 2 only at the edge of the liquid crystal panel 1 where a signal input is required.

FIGS. 6 and 7 are a plan view and a side view showing the structure of the inspection signal input unit 3. As is apparent from these drawings, the inspection signal input unit 3 has a printed circuit board 3e described later. A flexible conductive plate 3a formed in a more comb-like shape, and contacts 3b provided on the flexible conductive plate 3a for directly contacting a plurality of signal input terminal portions of the liquid crystal panel 1 to input an electric signal, A pressing member 3c that presses the flexible conductive plate 3a, a printed circuit board 3d that leads out each flexible conductive plate 3a, and the flexible conductive plate 3a, the pressing member 3c, and the printed circuit board 3d are fixed and connected to a drive unit. Drive plate 3e.

FIG. 8 shows the details of the flexible conductive plate 3a, the pressing member 3c, and the signal input portion of the liquid crystal panel 1. As shown in FIG. 8, a cushioning material is provided at the tip of the pressing member 3c. As described above, since the urethane rubber 3f is attached, it is possible to absorb the attachment accuracy of the pressing member 3c, the bending of the liquid crystal panel 1, and the like, and it is possible to omit the mechanism for performing minute height adjustment for each pressing member 3c.

The hardness of the urethane rubber 3f is 30 degrees or more.
It is preferable that the elastic property of 50 degrees is high, and regarding the shape, when the size is outside the terminal portion of the liquid crystal panel 1, when the flexible conductive plate 3a is connected to the terminal portion of the liquid crystal panel, the above-mentioned minute Since the height adjusting mechanism is not installed, pressure is applied to the edge of the terminal portion of the liquid crystal panel, so that sufficient pressure is not applied to the contact 3b, and the lighting signal cannot be normally input. . Therefore, it is necessary to make the size of the urethane rubber 3f such that the urethane rubber 3f fits inside the terminal portion of the liquid crystal panel 1.

As shown in FIG. 9, the inspection signal input unit 3 having the above-mentioned configuration is brought into contact with the liquid crystal panel 1 in order to avoid contact with the liquid crystal panel 1 when the liquid crystal panel 1 is removed after the inspection. From the state, as shown by an arrow A, it is vertically moved up by 2 to 3 mm, and then, as shown by an arrow B, it is moved backward by about 30 mm in a direction to separate from the liquid crystal panel. On the other hand, when inspecting the liquid crystal panel 1, the liquid crystal panel 1 is set on the holding plate 2 and the inspection signal input unit 3 is moved in the horizontal direction with respect to the liquid crystal panel 1 by the operation opposite to the case where the liquid crystal panel 1 is removed after the inspection. And move them down to connect them.

In this way, the contact 3 of the flexible conductive plate 3a is always
The reason why the surface b is on the lower side is to prevent the operator's hand from contacting and damaging the surface of the contact 3b of the flexible conductive plate 3a when the liquid crystal panel is attached or detached. In addition, since the components are brought closer to each other in the horizontal direction and then lowered from the upper portion, scratches at the time of contact can be reduced and abrasion of the contact 3b can be prevented.

Further, the polarizing plate 11 provided on the upper surface of the liquid crystal panel 1 is preferably a polarizing plate including an antireflection layer in order to prevent reflection of ambient light and the like so that an inspection operator does not overlook it. In order to use the polarizing plate, it is necessary to bring it into close contact with the upper side of the liquid crystal panel 1.

Compared with the case where the inspection signal input unit 3 is collectively fixed by the holding plate as in the prior art, the inspection signal input unit 3 is installed on the holding plate 2 only on the necessary side of the liquid crystal panel 1. Therefore, the space on the upper side of the liquid crystal panel 1 can be widened, and the polarizing plate 15 including the antireflection layer is provided with signal input terminal portions on the upper side and the left side of the liquid crystal panel 1 as shown in FIGS. If there is
The upper left corner can be installed in common.

By enlarging the polarizing plate 15 including this antireflection layer, it is common to inspect liquid crystal panels of the same type, that is, liquid crystal panels of different sizes having signal input terminal portions on the upper and left sides of the liquid crystal panel 1. It is not necessary to prepare a polarizing plate for each size.

FIG. 12 shows a holding means for the polarizing plate 15. As shown in FIG. 12, a polarizing plate is provided between a plate 16 having the same thickness as the liquid crystal panel 1 and a plate 17 thicker than the plate 16. The polarizing plate holder has a structure in which a gap plate 18 having the same thickness as 15 is sandwiched. With this configuration, the polarizing plate 15 can be held by a free hand without being displaced from the tilted inspection jig of the liquid crystal panel 1.

When there are signal input terminal portions on the lower side and the left side of the liquid crystal panel 1, the polarizing plate 15 can be installed so that the lower left corner portion is common. The method of holding the polarizing plate 15 at this time is necessary when the polarizing plate 15 can be mounted on the inspection signal input unit 3 when it comes into contact with the liquid crystal panel 1, and the above-mentioned upper left corner portion is common. The above-mentioned polarizing plate holder is unnecessary.

In the future, when inspecting a liquid crystal panel having a wide viewing angle characteristic on the polarizing plate side, it is necessary to bring the polarizing plate into close contact with the liquid crystal panel. In that case, the inspection jig of the present invention is utilized. Thus, the inspection of the liquid crystal panel can be performed successfully.

[0037]

According to the present invention, since the polarizing plate, the lens sheet, the diffusing plate and the like are laminated and provided on the lower surface of the liquid crystal panel held by the holding plate, the bending of these laminated bodies including the liquid crystal panel is reduced. In addition, the efficiency of the backlight is improved by using the lens sheet and the diffusion plate together, and the inspection accuracy of the liquid crystal panel can be improved. Moreover, since there is no gap between the liquid crystal panel and the polarizing plate, there is an erroneous detection at the time of inspecting the liquid crystal panel, which is caused by the space formed between the liquid crystal panel and the lower polarizing plate in the prior art, that is, when the liquid crystal panel is inspected. It is possible to see scratches, dust, and the like of the lower polarizing plate and the backlight after passing through the panel, and eliminate erroneous detection such as overlooking small pixel defects and scratches in the CF substrate.

Further, a push-up pin that moves up and down is provided at the edge of the opening of the holding plate, and the push-up pin allows the liquid crystal panel to float above the holding plate, thereby removing the liquid crystal panel from the holding plate. At this time, the liquid crystal panel can be easily lifted from the holding plate by moving the push-up pin upward, and the liquid crystal panel can be easily removed.

A push-up pin that moves up and down is provided at the edge of the opening of the holding plate, and a positioning member for positioning the liquid crystal panel on the holding plate is provided at a position opposite to the position where the push-up pin is provided. If the liquid crystal panel is provided and the positioning member is used as a fulcrum to lift the liquid crystal panel from the holding plate by the push-up pin, the liquid crystal panel can be easily removed.

Further, by disposing the inspection signal input unit for inputting the inspection signal only on the side of the liquid crystal panel where the inspection signal needs to be input, the inspection signal input unit is arranged on the holding plate. The number of parts of the jig can be reduced as much as possible.

Further, the upper polarizing plate can be easily attached to the upper surface of the liquid crystal panel by providing the upper plate with the holder for closely placing the upper polarizing plate on the upper surface of the liquid crystal panel. Can be held without slipping off.

Further, the supporting arm provided upright on the substrate plate is supported by the backlight unit so as to be able to displace the tilt angle, so that the substrate is mounted on the substrate while the liquid crystal panel is mounted on the inspection jig. The tilt angle can be changed on the plate, and the liquid crystal panel can be easily inspected.

[Brief description of drawings]

FIG. 1 is a front view of a state in which a liquid crystal panel is attached to an inspection jig according to an embodiment of the present invention.

FIG. 2 is a side view showing a state in which a liquid crystal panel is attached to the inspection jig according to the embodiment of the present invention.

FIG. 3 is a schematic view showing a holding plate portion in the above-mentioned inspection jig.

FIG. 4 is a schematic view showing a state in which the upper side of the liquid crystal panel is pushed up by a push-up pin in the above-mentioned inspection jig.

FIG. 5 is a schematic view showing a state where the lower side of the liquid crystal panel is pushed up by a push-up pin in the above-mentioned inspection jig.

FIG. 6 is a top view showing an inspection signal input unit in the above inspection jig.

FIG. 7 is a side view showing an inspection signal input unit in the above inspection jig.

FIG. 8 is an enlarged side view showing the relationship between the flexible conductive plate, the pressing member and the signal input section of the liquid crystal panel in the above inspection jig.

FIG. 9 is a view showing a state in which the inspection signal input unit in the inspection jig is attached.

FIG. 10 is a front view showing a state in which a liquid crystal panel having an upper polarizing plate on the upper surface is attached to the inspection jig of the present invention.

FIG. 11 is a bottom view showing a state in which the liquid crystal panel having the upper polarizing plate is attached to the inspection jig of the present invention.

FIG. 12 is a schematic view showing a method of attaching the upper polarizing plate to the holding plate.

FIG. 13 is a perspective view showing a state in which a liquid crystal panel is attached to a conventional inspection jig.

FIG. 14 is a schematic side sectional view showing a state in which a liquid crystal panel is attached to a conventional inspection jig.

[Explanation of symbols]

1 LCD panel 2 holding plate 3 Inspection signal input unit 4 backlight 6 substrate plate 8 Positioning member 9 Diffuser 10 lens sheet 11 Polarizer 12 Fitting part 13 Polarizer holding plate 14 Push-up pin 15 Polarizer

Claims (6)

[Claims] 1. A liquid crystal panel is detachably held, and a display plate of the liquid crystal panel is provided with a holding plate made of a frame having an opening for taking in light from a backlight, and a downward direction is provided at a peripheral portion of the opening of the holding plate. A recess having a predetermined depth is formed on the base plate as a fitting part, and the peripheral parts such as a polarizing plate, a lens sheet, and a diffusion plate, which are stacked and arranged on the lower surface of the liquid crystal panel, are fitted and mounted on the fitting part. A jig for inspecting a liquid crystal panel, which is characterized by: 2. The liquid crystal according to claim 1, wherein a push-up pin that moves up and down is provided at an edge of the opening of the holding plate, and the push-up pin lifts the liquid crystal panel from the holding plate. Jig for panel inspection. 3. A positioning pin is provided at the edge of the opening of the holding plate for moving up and down, and is positioned at a position opposite to the position where the lifting pin is provided to position the liquid crystal panel on the holding plate. The jig for inspecting a liquid crystal panel according to claim 2, wherein a member is provided and the push-up pin lifts the liquid crystal panel from the holding plate with the positioning member as a fulcrum. 4. An inspection signal input unit for inputting the inspection signal to only the side of the liquid crystal panel where the inspection signal needs to be input is arranged on the holding plate. The jig for inspecting a liquid crystal panel according to claim 1. 5. A holding tool for closely arranging a polarizing plate on the upper surface of the liquid crystal panel is provided.
4. A liquid crystal panel inspection jig according to any one of 4 above. 6. The jig for inspecting a liquid crystal panel according to claim 1, which is supported by a supporting arm erected on a substrate plate so as to be capable of displacing an inclination angle by the backlight portion.