KR20100044026A - Liquid crystal display device - Google Patents

Abstract

PURPOSE: An LCD device is provided to drastically reduce a manufacturing cost and the weight by eliminating a guide panel. CONSTITUTION: An optical sheet(141) is attached to the rear side of liquid crystal panel which image is embodied. At least one of the lamp(142) supplies a light to a liquid crystal panel. A lower cover(150) receives the lamps. The lower cover supports the liquid crystal panel which optical sheet is attached. An upper cover(130) supports a part of the liquid crystal panel. The upper cover is combined with the lower cover.

Description

[0001] LIQUID CRYSTAL DISPLAY DEVICE [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly, to a liquid crystal display device capable of greatly reducing manufacturing costs and greatly reducing weight by removing a guide panel.

Recently, with the development of various portable electronic devices such as mobile phones, PDAs, and notebook computers, there is a growing demand for flat panel display devices for light and thin applications. Such flat panel displays are being actively researched, such as LCD (Liquid Crystal Display), PDP (Plasma Display Panel), FED (Field Emission Display), VFD (Vacuum Fluorescent Display), but mass production technology, ease of driving means, Liquid crystal display devices (LCDs) are in the spotlight for reasons of implementation.

The liquid crystal display device is a transmissive display device, and a desired image is displayed on the screen by controlling the amount of light passing through the liquid crystal layer by the refractive index anisotropy of the liquid crystal molecules. As a result, a backlight for transmitting light through the liquid crystal layer is required.

1 is a view showing a conventional liquid crystal display device having a backlight as described above.

As shown in FIG. 1, the liquid crystal display device 1 includes a liquid crystal panel 10 in which a plurality of pixels are arranged in a matrix form, and a guide panel supporting a rear edge and side surfaces of the liquid crystal panel 10. 20 and the upper cover 30 which is pressed against the upper edge of the liquid crystal panel 10 and coupled to the side surface of the guide panel 20, and the side surface and the screw 51 of the guide panel 20. The lower cover 50 is coupled to support the backlight 40.

The backlight 40 includes a reflecting plate 41 provided on an upper surface of the lower cover 50, a plurality of lamps 42 for injecting light into the entire rear surface of the liquid crystal panel 10, and the lamps 42. And a diffusion plate 44 disposed between the liquid crystal panel 10 and diffusing the light incident from the lamp 42 to the liquid crystal panel 10 and supported by the lower cover 50 at the rear edge thereof. It consists of an optical sheet 45 disposed on the upper surface of the diffusion plate 44, the liquid crystal panel 10 and the optical sheet 45 has a predetermined interval by the protrusion of the guide panel 20.

As described above, in the conventional liquid crystal display device, the guide panel 20 is provided to support the liquid crystal panel 10, the diffusion plate 44, and the optical sheet 45. It is possible to prevent the diffusion plate 44 and the optical sheet 45 from flowing.

However, the above-described conventional liquid crystal display has the following problems.

As shown in FIG. 1, the guide panel 20 is formed in the entire outer region of the liquid crystal panel 10 to couple the liquid crystal panel 10, the lower cover 50, and the upper cover 30. Therefore, when the liquid crystal display device 10 is manufactured, the guide panel 20 becomes an important cause of increasing weight of the liquid crystal display device 10. In addition, the area of the liquid crystal display device 1 is increasing with the recent development of technology. As the area increases, the size of the guide panel 20 also increases, so that the weight of the liquid crystal display device 10 is further increased. There was a problem.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a liquid crystal display device which can reduce the manufacturing cost and significantly reduce the manufacturing cost by eliminating the number of parts by removing the guide panel and the diffusion plate. .

In order to achieve the above object, the liquid crystal display device according to the present invention comprises an optical sheet attached to the rear of the liquid crystal panel is implemented image; At least one lamp supplying light to the liquid crystal panel; A lower cover accommodating the lamp and supporting the liquid crystal panel to which the optical sheet is attached; An upper cover supporting a portion of an upper surface of the liquid crystal panel and coupled to the lower cover; And a protrusion formed on one of the lower cover and the upper cover to fix the liquid crystal panel.

The protrusion is a kind of stopper that prevents the liquid crystal panel from flowing. The protrusion is formed integrally with or separately from the lower cover or the upper cover, and is formed on the bottom of the lower cover to reflect the light incident from the lamp to the liquid crystal panel. It is formed into a lens shape for scattering light.

In the present invention, by removing the guide panel and the diffusion plate in the liquid crystal display, not only can the weight be greatly reduced, but also the manufacturing cost can be reduced.

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

2 is a view showing a liquid crystal display device according to the present invention. As shown in FIG. 2, the liquid crystal display device 100 is provided with a liquid crystal panel 110 in which a plurality of pixels are arranged in a matrix form, and is disposed under the liquid crystal panel 110 to supply light to the liquid crystal panel 110. A backlight 140, an upper cover 130 for pressing the upper edge of the liquid crystal panel 110, and a lower cover 150 for supporting the backlight 140 by being combined with the upper cover 130. .

The backlight 140 is provided on an upper portion of the lower cover 150 to provide light to the liquid crystal panel 110 to emit light, and is provided on an upper surface of the lower cover 150. A reflecting plate 141 reflecting light incident from the light source 142 to the liquid crystal panel 110, a diffusion sheet attached to a lower portion of the liquid crystal panel 110, and a diffusion sheet for diffusing light incident from the lamp 142. It consists of an optical sheet 141 made of a prism sheet for adjusting the path of the light.

In the liquid crystal display device 100 according to the present invention configured as described above, the liquid crystal panel 110 to which the optical sheet 141 is attached is in direct contact with the upper surface of the side of the lower cover 150, and the side surface of the lower cover 150 is upper. In contact with and coupled to the side of the cover 130. Although not shown in the drawings, the lower cover 130 and the lower cover 150 may be coupled by a screw, or may be made by an adhesive means such as an adhesive or a double-sided tape.

The liquid crystal panel 110 is placed on the upper surface of the lower cover 150. Although only a cross section is illustrated in the drawing, since the lower cover 150 is formed along four sides of the liquid crystal display, four sides (ie, entire edge regions) of the liquid crystal panel 110 are formed on the lower cover 150. The liquid crystal panel 110 is supported by the lower cover 150 to be placed on the upper surface.

On the other hand, the protrusion (150a) is formed on the upper portion of the lower cover 150. The protrusion 150a is a kind of stopper. When an external force acts on the liquid crystal panel 110 from the outside, the protrusion 150a firmly fixes the liquid crystal panel 110 to prevent the liquid crystal panel 110 from flowing. In this case, since the protrusion 150a is formed over the entire upper surface of the lower cover 150 (as formed along the edge of the liquid crystal panel 110), the liquid crystal panel 110 is supported on the upper surface of the lower cover 150. In this case, since four side surfaces of the liquid crystal panel 110 are in contact with the protrusions 150a, the liquid crystal panel 110 may be prevented from flowing due to external force in four directions.

The backlight 140 is a direct type backlight. That is, in the backlight 140, the lamp 142 is disposed under the liquid crystal panel 110, and the light emitted from the lamp 142 is directly incident on the liquid crystal panel 110.

Compared to a conventional edge type backlight, in which a lamp is formed at one side of the backlight and light incident from the lamp is supplied to the liquid crystal panel through the light guide plate, the direct type backlight 140 has light emitted from the lamp 142. Since it is directly supplied to the liquid crystal panel 110, it is mainly used for the large area liquid crystal display device 100 with high luminance.

The lamp 142 mainly uses a cold cathode fluorescent lamp or an external electrode fluorescent lamp, but various types of light sources, such as a light emitting device (LED), may be used.

The liquid crystal panel 110 implements an image by adjusting the transmittance of light incident from the lamp 142. The structure thereof will be described with reference to FIGS. 3A and 3B as follows.

3A is a plan view showing the structure of a liquid crystal panel. As shown in FIG. 3A, the liquid crystal panel 110 includes a plurality of pixels 119, each of which includes a gate line 114 to which a scan signal is applied from an external driving circuit and data to which an image signal is applied. And a thin film transistor formed at an intersection region of the line 116. The thin film transistor includes a gate electrode 113 connected to the gate line 114, a semiconductor layer 118 formed on the gate electrode 113 and activated when a scan signal is applied to the gate electrode 113, and the semiconductor. And a source / drain electrode 115 formed over the layer 118. As the semiconductor layer 118 is activated by being connected to the source / drain electrode 115 in the display area of the pixel 119, an image signal is applied through the source / drain electrode 115 so that the liquid crystal (not shown) is not shown. Is formed on the pixel electrode 111.

3B is a cross-sectional view of the liquid crystal panel. As shown in FIG. 3B, the liquid crystal panel 100 includes a first substrate 170 and a second substrate 180 made of a transparent insulating material such as glass, and a gate electrode 113 formed on the first substrate 170. ), A gate insulating layer 172 stacked over the entire substrate 170 on which the gate electrode 113 is formed, and formed on the gate insulating layer 172 to be activated when a signal is applied to the gate electrode 113. A semiconductor layer 116, a source / drain electrode 115 formed on the semiconductor layer 116, a passivation layer 174 formed on the source / drain electrode 115 to protect the device, and A pixel electrode 111 formed on the passivation layer 174 and connected to the source / drain electrodes 115 of the thin film transistor through a contact hole formed in the passivation layer 174, to which an image signal is applied through the thin film transistor; Formed on the second substrate 180 to form a thin film transistor forming region and a gate line A black matrix 182 formed in an image non-display area such as an inverse and a data line forming area to block light transmitted to the corresponding area, and a R (red) formed on the second substrate 180. , A color filter layer 184 consisting of a sub-color filter of G (Green) and B (Blue) to realize an actual image, and an image signal applied to the pixel electrode 111 formed on the second substrate 180. Accordingly, the pixel electrode 111 includes a common electrode 186 forming an electric field, and a liquid crystal layer 190 formed between the first substrate 170 and the second substrate 180.

In the liquid crystal panel 110 configured as described above, when a scan signal from an external driving element is input to the gate electrode 113 of the thin film transistor along the gate line 114, the semiconductor layer 118 is activated to form a channel layer. At the same time, an image signal is input from the external driving element to the pixel electrode 111 through the data line 116 and the source / drain electrode 115. As the image signal is input to the pixel electrode 111, an electric field is formed between the pixel electrode 111 and the common electrode 186 and applied to the liquid crystal layer 190. The liquid crystal molecules of the liquid crystal layer 190 are arranged in accordance with the applied electric field to adjust the transmittance of the light passing through the liquid crystal layer 190.

The first polarizing plate 176 and the second polarizing plate 188 are attached to the outside of the first substrate 170 and the second substrate 180, respectively. The first polarizing plate 176 and the second polarizing plate 188 have polarization axes parallel or perpendicular to each other, and are linearly polarized through the first polarizing plate 176 to provide light having a changed polarization direction to the liquid crystal layer 190. By transmitting or blocking the polarizing plate 188, the transmittance of light passing through the liquid crystal layer 190 may be adjusted.

The optical sheet 141 is attached to the first polarizing plate 176 by an adhesive layer 178. The optical sheet 141 is composed of one or more diffusion sheets or prism sheets, and diffuses or condenses the light incident from the lamp 141 to supply uniform light to the liquid crystal panel 110.

As described above, in the liquid crystal display according to the present invention, the optical sheet 141 is directly attached to the liquid crystal panel 110 and diffuses and condenses the light incident from the lamp 141 to supply the liquid crystal panel 110. Further, in the present invention, the guide panel provided in the conventional liquid crystal display device can be removed.

Typically, the guide panel not only fixes the liquid crystal panel and the diffusion plate but also serves to fix the optical sheet. The diffusion plate is made of a solid and flat plate shape, the optical sheet is made of a flexible and elastic sheet. Therefore, in the conventional liquid crystal display device, the optical sheet is provided on the diffusion plate fixed to the guide panel so that the flexible optical sheet can be fixed between the liquid crystal panel and the lamp.

In the present invention, by attaching the optical sheet 141 directly to the liquid crystal panel 110, there is no need for a rigid plate-shaped diffusion plate for supporting the optical sheet. That is, since the liquid crystal panel 110 itself has a rigid plate shape, the optical sheet 141 may be prevented from bent by attaching the optical sheet 141 to the liquid crystal panel 110. In addition, since the liquid crystal panel 110 is fixed by the protrusion 150a formed on the lower cover 150, the liquid crystal panel 110 may be prevented from flowing by external force from the outside. As a result, in the present invention, it is possible to remove not only the guide panel but also the diffusion plate from the liquid crystal display device 100, so that the number of parts of the liquid crystal display device can be greatly reduced, so that the weight of the liquid crystal display device can be greatly reduced. And the manufacturing cost can be reduced.

The protrusion 150a is generally preferably formed integrally with the lower cover 150, but may be formed as a separate 150a and installed on the lower cover 150.

In addition, as shown in FIG. 4, the protrusion 150a may be formed on the upper cover 230. That is, since the upper cover 230 and the lower cover 250 are coupled by a coupling means such as a screw coupling or an adhesive, a protrusion 230a, that is, a stopper is formed on the upper cover 230 and placed on the lower cover 250. Even when the liquid crystal panel 210 is fixed, the liquid crystal panel 210 can be prevented from flowing by external force.

On the other hand, unlike the prior art, since the diffusion plate as well as the guide panel is removed in the present invention, the light emitted from the lamp is first incident on the optical sheet in the non-diffused state and then supplied to the liquid crystal panel. Therefore, the liquid crystal panel and the optical sheet should be spaced more than a predetermined distance.

In view of this point, in the present invention, it is possible to uniformly supply light to the liquid crystal panel 310 by improving the efficiency of light reflected from the reflecting plate and supplied to the liquid crystal panel.

FIG. 5A illustrates a structure of a liquid crystal display 300 in which a reflecting plate 341 of the backlight 340 is formed in a microlens shape. In the liquid crystal display 300 having the structure, light reflected from the lamp 342 is reflected in the microlens. After scattering by the light, the light is incident on the optical sheet 344 to improve the light efficiency. At this time, although only the configuration in which the reflecting plate 341 is made of concave microlenses is illustrated, the reflecting plate 341 may be made of convex microlenses or may be made of convex or concave lenses having a predetermined curvature. In addition, the reflective plate 341 may be formed in a polygonal shape such as a triangle shape. In other words, the reflecting plate 341 may be in any form as long as it can scatter the light incident from the lamp 342 and uniformize the light incident on the optical sheet 344.

FIG. 5B illustrates a structure of the liquid crystal display device 300 in which a diffusion layer 343 made of a diffusion material is formed on the reflective plate 341 of the backlight 340. In the liquid crystal display device 300 having the structure, the light is reflected from the lamp 342. After the light is diffused in the diffusion layer 343, the light diffused into the optical sheet 344 is incident to improve the light efficiency.

As described above, in the present invention, since the optical sheet is directly attached to the liquid crystal panel, the guide panel and the diffusion plate, which are conventionally provided, can be removed, thereby reducing the manufacturing cost and greatly reducing the weight of the liquid crystal display device. It becomes possible.

In the above detailed description of the present invention, the structure of the liquid crystal panel, the structure of the projections, the shape of the reflecting plate, and the like have been described as specific structures. For example, in addition to the structure of the liquid crystal panel disclosed in the above description, the common electrode and the pixel electrode are arranged parallel to the same substrate with a predetermined width to form an electric field parallel to the surface of the substrate, thereby rotating the liquid crystal molecules on the plane of the substrate. In-plane switching mode to improve aperture ratio Liquid crystal display devices in various driving modes such as liquid crystal display devices or vertical alignment mode in which liquid crystal molecules are oriented perpendicular to the surface of the substrate. It may be applied to a liquid crystal display device of various display modes such as a transmissive liquid crystal display device, a reflective liquid crystal display device or a transflective liquid crystal display device. In addition, the shape of the protrusions formed on the lower cover or the upper cover may also be applied to a variety of shapes, such as square or curved. In other words, other examples or modifications of the present invention can be easily created by anyone in the technical field to which the liquid crystal display device using the basic concept of the present invention belongs.

1 is a view showing the structure of a conventional liquid crystal display device.

2 is a diagram illustrating a structure of a liquid crystal display according to an exemplary embodiment of the present invention.

Figure 3a is a plan view showing the structure of a liquid crystal panel according to the present invention.

Figure 3b is a cross-sectional view showing the structure of a liquid crystal panel according to the present invention.

4 is a diagram illustrating a structure of a liquid crystal display according to another exemplary embodiment of the present invention.

5A and 5B are views showing the structure of a liquid crystal display according to yet another embodiment of the present invention, respectively.

Claims (10)

An optical sheet attached to a rear side of a liquid crystal panel in which an image is implemented; At least one lamp supplying light to the liquid crystal panel; A lower cover accommodating the lamp and supporting the liquid crystal panel to which the optical sheet is attached; An upper cover supporting a portion of an upper surface of the liquid crystal panel and coupled to the lower cover; And And a projection formed on one of the lower cover and the upper cover to fix the liquid crystal panel. The method of claim 1, wherein the optical sheet, At least one diffusion sheet; And And at least one prism sheet. The liquid crystal display device according to claim 1, further comprising a screw for coupling the upper cover and the lower cover. The liquid crystal display device according to claim 1, further comprising an adhesive for bonding the upper cover and the lower cover. The liquid crystal display of claim 1, wherein the protrusion is integrally formed with a lower cover or an upper cover. The liquid crystal display of claim 1, wherein the protrusion is formed separately from the lower cover or the upper cover and installed on the lower cover or the upper cover. 8. The liquid crystal display device according to claim 7, further comprising an adhesive layer for adhering the liquid crystal panel and the optical sheet. The liquid crystal display device of claim 1, further comprising a reflector formed on a bottom surface of the lower cover to reflect light incident from a lamp to the liquid crystal panel. The liquid crystal display device according to claim 8, wherein the reflecting plate is formed in a lens shape for scattering light incident from a lamp. The method of claim 1, A reflection plate formed on a bottom surface of the lower cover to reflect light incident from the lamp to the liquid crystal panel; And And a diffusion layer formed on the reflection plate to diffuse light incident on the reflection plate.

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