KR101661285B1 - Liquid Crystal Display Device - Google Patents

Abstract

The present invention discloses a liquid crystal display device. A liquid crystal display device of the present invention includes: a liquid crystal display panel; And a backlight unit including a light guide plate for supplying a light source to the liquid crystal display panel, a lamp for supplying a light source to the light guide plate, and an optical sheet disposed between the liquid crystal display panel and the light guide plate, At least one of the first polarizing plate and the second polarizing plate is separated from the static electricity by the liquid crystal, and the first polarizing plate and the second polarizing plate are attached to the back surface of the upper substrate and the lower substrate, respectively, And a conductive layer for protecting the display panel is integrally formed.

The present invention has the effect of easily shielding the static electricity generated in the liquid crystal display device by using the conductive polarizer.

Liquid crystal display, static electricity, polarizing plate, conductive, ground, picture quality

Description

[0001] The present invention relates to a liquid crystal display device,

The present invention relates to a liquid crystal display device.

2. Description of the Related Art [0002] Liquid crystal displays (LCDs) are becoming more and more widespread due to features such as light weight, thinness, and low power consumption driving. According to this trend, liquid crystal display devices are used in office automation equipment, audio / video equipment, and the like. The liquid crystal display device displays a desired image on the screen by controlling the amount of transmitted light according to a video signal applied to a plurality of control switches arranged in a matrix form.

Such a liquid crystal display device has a structure in which an upper substrate on which a color filter layer is formed, a lower substrate on which a thin film transistor (Thin Film Transistor) and a pixel electrode are formed, are bonded together with a liquid crystal layer interposed therebetween.

A polarizer and a retardation film are attached to the outer surfaces of the upper substrate and the lower substrate. By selectively configuring such a plurality of components, the liquid crystal display device adjusts brightness and contrast ratio characteristics by changing the progress of light or changing the refractive index.

A liquid crystal display controls liquid crystal molecules contained in a liquid crystal layer by rotating an electric field to control the transmittance. Generally, a common electrode is formed on an upper substrate, a pixel electrode is formed on a lower substrate, Nematic mode was used.

However, such a TN mode has a disadvantage in that it has a narrow viewing angle because it has a characteristic that light transmittance in gradation display is changed according to the viewing angle.

In order to improve this, an in-plane switching mode (hereinafter referred to as "IPS mode") using a parallel electric field was developed. In the transverse electric field mode, a common electrode and a pixel electrode are formed on a lower substrate, And is a mode for rotating liquid crystal molecules by an electric field.

Such a transverse electric field mode significantly improves the viewing angle characteristics such as contrast ratio, gray inversion, and color shift compared to the conventional TN mode.

However, the liquid crystal display device of the transverse electric field mode is vulnerable to the static electricity applied from the outside of the liquid crystal display device because there is no common electrode on the upper substrate.

Such static electricity affects the arrangement of the liquid crystal molecules in the liquid crystal layer disposed between the upper substrate and the lower substrate to change the transmittance of the liquid crystal molecules. Such a change in the transmittance of the liquid crystal molecules causes a deterioration in image quality.

The present invention provides a liquid crystal display device capable of increasing brightness and improving picture quality by removing static electricity applied to a liquid crystal display device using a conductive polarizer.

According to an aspect of the present invention, there is provided a liquid crystal display device including: a liquid crystal display panel; And a backlight unit including a light guide plate for supplying a light source to the liquid crystal display panel, a lamp for supplying a light source to the light guide plate, and an optical sheet disposed between the liquid crystal display panel and the light guide plate, At least one of the first polarizing plate and the second polarizing plate is separated from the static electricity by the liquid crystal, and the first polarizing plate and the second polarizing plate are attached to the back surface of the upper substrate and the lower substrate, respectively, And a conductive layer for protecting the display panel is integrally formed.

Here, the display device may further include a support main body in which the liquid crystal display panel and the backlight unit are assembled, and a top cover and a bottom cover assembled on the upper and lower sides of the entire support main body in which the liquid crystal display panel and the backlight unit are assembled.

In the polarizing plate including the conductive layer, a first protective layer and a second protective layer are formed on both sides of the polarizing layer, and a conductive layer is formed on the back surface of the first protective layer or the second protective layer along the entire surface of the polarizing plate Wherein the polarizing plate including the conductive layer is electrically connected to the front layer by a conductive sealant formed on an upper substrate or a lower substrate of the liquid crystal display panel and then electrically connected to the conductive sealant by a conductive tape electrically connected to the conductive sealant, And is electrically grounded with the top cover or the bottom cover.

The present invention has the effect of increasing the brightness and improving the image quality by removing the static electricity applied to the liquid crystal display device by using the conductive polarizer.

In addition, the present invention can reduce the production time and production cost by forming the conductive layer integrally on the polarizing plate, thereby reducing the formation of additional components or the use of equipment for preventing static electricity.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The following embodiments are provided by way of example so that those skilled in the art can fully understand the spirit of the present invention. Therefore, the present invention is not limited to the embodiments described below, but may be embodied in other forms. In the drawings, the size and thickness of the device may be exaggerated for convenience. Like reference numerals designate like elements throughout the specification.

1 is an exploded perspective view of a liquid crystal display device according to the present invention.

1, the liquid crystal display device mainly includes a liquid crystal display panel 10, a backlight unit 20, a support main body 30, a lower cover 50, and a top cover 40. The liquid crystal display panel 10 is composed of an upper substrate 10a and a lower substrate 10b which face each other with a liquid crystal layer sandwiched therebetween, which plays a key role in image display. A gate printed circuit board 11 for supplying a driving signal and a data printed circuit board 12 for supplying a data signal to the liquid crystal display panel 10 are connected to one edge of the liquid crystal display panel 10 have.

A color filter layer is formed on the upper substrate 10a, and a TFT and a pixel electrode are formed on the lower substrate 10b. Since the present invention is for preventing static electricity generated in the IPS mode liquid crystal display device, a common electrode and a pixel electrode are formed on the lower substrate 10b. However, the present invention is also applicable to a TN mode liquid crystal display device in which a common electrode is formed on an upper substrate 10a and a pixel electrode is formed on a lower substrate 10b.

A first polarizing plate 13a and a second polarizing plate 13b are disposed on the upper and lower portions of the liquid crystal display panel 10. In the present invention, the first polarizing plate 13a attached to the back surface of the upper substrate 10a A conductive polarizing plate on which a conductive layer is formed is used.

However, since this is not fixed, a conductive polarizing plate having a conductive layer formed on both the first polarizing plate 13a and the second polarizing plate 13b may be used, or any one polarizing plate may be used as the conductive polarizing plate.

A backlight unit 20 is provided behind the liquid crystal display panel 10.

At this time, the backlight unit 20 includes first and second lamps 24a and 24b disposed along the lengthwise opposite side edges of the support main body 30, and first and second lamps 24a and 24b A first or second lamp housing 25a or 25b for fixing the first and second lamp housings 25a and 25b on the lower cover 50 and a white or silver reflector 22 seated on the lower cover 50, 24a, and 24b to generate a planar light source, and a plurality of optical sheets 28 interposed therebetween.

The liquid crystal display panel 10 and the backlight unit 20 are assembled on the upper and lower sides of the support main body 30 having a rectangular frame shape and then mounted on a top cover 40 and the lower cover 50 covering the back surface of the backlight unit 20, and are integrated through the support main 30.

The light emitted from the first and second lamps 24a and 24b is incident on the light entrance portion of the light guide plate 26 and is refracted in the direction of the liquid crystal display panel 10. While passing through the plurality of optical sheets 28 And is incident on the liquid crystal display panel 10. As a result, the liquid crystal display panel 10 displays an image on the outside.

2 is a cross-sectional view showing the structure of the conductive polarizer used in the liquid crystal display device of the present invention.

As shown in FIG. 2, the first polarizing plate 13a, which is a conductive polarizing plate, has a polarizing layer 30 disposed at the center thereof. The first and second protective layers 32a and 32b are formed on the upper and lower sides of the polarizing layer 30, And a layer 32b are formed. A conductive layer 34 is formed under the second protective layer 32b.

The conductive layer 34 may be formed by attaching a transparent conductive material such as ITO in the form of a sheet or directly printing on the back surface of the second protective layer 32b. The conductive layer 34 has the same area as the front surface of the conductive polarizer.

In addition, when a conductive metal such as copper (Cu) or silver (Ag) is formed to have a small thickness although not a transparent conductive material, the conductive property can be maintained while maintaining transparency.

The thickness of the conductive layer 34 may be varied depending on the kind of the material within a range where the transmittance is 42% or more.

FIG. 3 is a view showing a structure in which the conductive polarizer of FIG. 2 is attached to a liquid crystal display panel.

3, a first polarizing plate 13a and a second polarizing plate 13b are attached to the upper substrate 10a and the lower substrate 10b of the liquid crystal display panel 10 by an adhesive layer 35, respectively, have.

When the first polarizing plate 13a is used as a conductive polarizing plate in order to prevent the static electricity of the liquid crystal display device, the conductive polarizing plate shown in FIG. 2 is used as the first polarizing plate 13a and the upper substrate 10a ) To the back.

The first polarizing plate 13a is attached to the back surface of the upper substrate 10a by the adhesive layer 35 in the same manner as the conventional polarizing plate attaching method. However, the conductive polarizer used in the liquid crystal display of the present invention has the conductive layer 34, the second protective layer 32b, the polarizing layer 30, and the first protective layer 32a on the basis of the back surface of the upper substrate 10a, Structure.

Therefore, when static electricity is generated from the outside, the conductive layer 34 formed on the first polarizing plate 13a has a function of shielding static electricity.

In the figure, the conductive polarizer is used only on the upper substrate 10a, but this is not fixed. Therefore, the second polarizing plate 13b may be manufactured using the same structure as the first polarizing plate 13a, which is a conductive polarizing plate, so that both the first polarizing plate 13a and the second polarizing plate 13b can be used as the conductive polarizing plate.

In some cases, only the second polarizing plate 13b attached to the rear surface of the lower substrate 10b may be used as the conductive polarizing plate.

4 is an assembled cross-sectional view of the liquid crystal display device of the present invention shown in Fig.

4, the liquid crystal display panel 10 is assembled on the upper side of the support main body 30 and the optical sheet 28, the light guide plate 26, the reflection plate 22, The lamp 24b and the second lamp housing 25b are housed with the lower cover 50 as a bottom surface.

A first polarizing plate 13a and a second polarizing plate 13b are attached to the back surface of the upper substrate 10a and the lower substrate 10b of the liquid crystal display panel 10, respectively. The conductive polarizing plate shown in Fig. 2 of the first polarizing plate 13a is used.

Since the first polarizing plate 13a includes a conductive layer, the first polarizing plate 13a is grounded to the outside, and the conductive tape 250 is attached to protect the liquid crystal display panel 10 from static electricity. A conductive sealant 260 is formed on the back surface of the upper substrate 10a at one edge region of the first polarizer 13a for electrical connection with the first polarizer 13a.

The conductive sealant 260 is formed on the back surface of the upper substrate 10a and is electrically connected to the conductive layer of the first polarizer 13a through the side surface of the first polarizer 13a.

Therefore, when the conductive tape 250 is electrically connected to the conductive sealant 260, the conductive tape 250 is electrically connected to the conductive layer of the first polarizer 13a.

The conductive tape 250 is electrically connected to the top cover 40 and the bottom cover 50 through the support main body 30.

Since the conductive tape 250 is so thin as to form the same plane as the first polarizing plate 13a, the assembly position of the top cover 40 to be fastened to the support main body 30 remains unchanged.

Fig. 5 is an enlarged cross-sectional view of the region A in Fig. 4. As shown in Fig. 5, a conductive first polarizing plate 13a is attached to the upper substrate 10a of the liquid crystal display panel 10 by an adhesive layer 35. Fig.

A conductive layer 34, a second protective layer 32b, a polarizing layer 30 and a first protective layer 32a of a first polarizing plate 13a are laminated on the adhesive layer 35. [ A conductive sealant 260 is formed on the back surface of the upper substrate 10a at the edge of the first polarizer 13a and the conductive sealant 260 is in electrical contact with the conductive layer 34 of the first polarizer 13a .

Therefore, the conductive sealant 260 needs to be equal to or higher than the height of the conductive layer 34 of the first polarizing plate 13a. A conductive tape 250 is electrically connected to the conductive sealant 260 and the height of the first polarizer 13a is equal to the height of the first protective layer 32a.

The conductive tape 250 is electrically connected to the conductive sealant 260. The conductive tape 250 is extended along the support main 30 to the outer cover 40 and the bottom cover and is electrically grounded. However, in some cases, the conductive tape 250 may be electrically attached and grounded along the inner surface of the top cover 40.

The conductive sealant 260 may be formed only in a region corresponding to the width of the conductive tape 250 along the periphery of the first polarizer 13a. For example, when the conductive tape 250 has a width of 1 to 5 cm, the conductive sealant 260 may be formed to have a width corresponding to the width of the conductive tape 250.

That is, the position where the conductive layer 34 of the first polarizing plate 13a is electrically grounded to the top cover 40 and the bottom cover 50 may be any region along the edge of the first polarizing plate 13a And, in some cases, one or more ground regions may be selected.

A conductive sealant 260 is formed in the region where the conductive layer 34 of the first polarizer 13a is to be electrically grounded and the conductive tape 250 is attached to the conductive tape 34, The liquid crystal display panel can be protected from static electricity by attaching it to the top cover 40 or the bottom cover 50.

As described above, according to the present invention, there is an advantage that the liquid crystal display can be shielded from static electricity without additional structural change or equipment input by using a polarizing plate in which the conductive layers are integrally formed.

1 is an exploded perspective view of a liquid crystal display device according to the present invention.

2 is a cross-sectional view showing the structure of the conductive polarizer used in the liquid crystal display device of the present invention.

FIG. 3 is a view showing a structure in which the conductive polarizer of FIG. 2 is attached to a liquid crystal display panel.

4 is an assembled cross-sectional view of the liquid crystal display device of the present invention shown in Fig.

5 is an enlarged cross-sectional view of region A in Fig.

 (Description of Reference Numbers to Main Parts of the Drawings)

10: liquid crystal display panel 20: backlight unit

30: Support main 22: Reflector

26: light guide plate 34: conductive layer

250: Conductive tape 260: Conductive sealant

Claims (6)

A liquid crystal display panel; And A backlight unit including a light guide plate for supplying a light source to the liquid crystal display panel, a lamp for supplying a light source to the light guide plate, and an optical sheet disposed between the liquid crystal display panel and the light guide plate, A support main body to which the liquid crystal display panel and the backlight unit are assembled; and a top cover and a bottom cover for assembling the entire support main body in which the liquid crystal display panel and the backlight unit are assembled, The liquid crystal display panel includes a first polarizer and a second polarizer attached to the back surface of the upper substrate and the lower substrate, respectively, with the upper substrate and the lower substrate interposed between the liquid crystal layers, At least one of the first polarizing plate and the second polarizing plate is integrally provided with a conductive layer for protecting the liquid crystal display panel from static electricity, And a conductive tape attached along an inner surface of the top cover, A conductive sealant is disposed on the upper substrate, and the conductive sealant is in electrical contact with the conductive layer and the conductive tape. delete The polarizing plate according to claim 1, wherein the polarizing plate including the conductive layer has a first protective layer and a second protective layer formed on both sides of the polarizing layer, Wherein the layer is disposed along the front surface of the polarizer. The method according to claim 1, And the height of the conductive sealant is equal to or higher than the conductive layer. The liquid crystal display of claim 1, wherein the conductive tape has the same height as an upper surface of the first polarizer or the second polarizer including the conductive layer. The method according to claim 1, Wherein the conductive sealant is provided only in a region corresponding to the width of the conductive tape along the circumference of the first polarizer or the second polarizer.

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