KR20080043167A - Liquid crystal display - Google Patents

Abstract

An LCD(Liquid Crystal Display) is provided to support a light guide plate effectively and stably while reducing the manufacturing cost by using ribs formed at a bottom cover. An LCD includes an LCD panel(120), a light guide plate(150), a light source(160), and a bottom cover(180). The light guide plate is located behind the LCD panel. The light source is located at one side of the light guide plate and provides light to the backside of the LCD. The bottom cover has a bottom surface(181) on which the light guide plate and the light source are mounted and a sidewall(182) extended upward from the bottom surface. The bottom cover includes ribs(183) for holding both sides of the light guide plate.

Description

Liquid Crystal Display {LIQUID CRYSTAL DISPLAY}

1A and 1B are views for explaining a light guide plate support structure of a conventional liquid crystal display device;

2 is an exploded perspective view of a liquid crystal display device according to a first embodiment of the present invention;

3 is a view for explaining a light guide plate support structure of a liquid crystal display device according to a first embodiment of the present invention;

4 is a cross-sectional view taken along line IV-IV of FIG. 3;

5 is a view for explaining a light guide plate support structure of a liquid crystal display according to a second embodiment of the present invention;

6 is a view for explaining a light guide plate supporting structure of a liquid crystal display according to a third exemplary embodiment of the present invention.

* Explanation of symbols for the main parts of the drawings

100: liquid crystal display 110: upper cover

120: liquid crystal panel 130: mold frame

140: optical sheet 150: light guide plate

160: light source 170: reflective sheet

180: lower cover 181: bottom part

182: side portion 183: rib

184: incision 185: support layer

The present invention relates to a liquid crystal display device, and more particularly, to a liquid crystal display device having a structure capable of effectively and stably supporting a light guide plate while reducing manufacturing costs.

In general, a liquid crystal display (LCD) is a device that displays a desired image by adjusting the light transmittance of liquid crystal cells arranged in a matrix form according to image signal information. Form an image on the panel.

As shown in FIG. 1A, the liquid crystal display device 1 includes a liquid crystal panel 20, an optical sheet 40 positioned on the rear surface of the liquid crystal panel 20, and an optical sheet from the liquid crystal panel 20. A mold frame 30 spaced apart from the support 40, a light guide plate 60 positioned on the rear surface of the optical sheet 40, a lamp unit 50 disposed along the side surface of the light guide plate 60, and a light guide plate. Reflective sheet 70 located on the back of the 60, and the upper cover 10 and the lower cover 80 for receiving the components therein and coupled to each other.

As shown in FIGS. 1A and 1B, the lamp unit 50 includes a lamp body 51 for generating light, a lamp holder 53 into which both ends of the lamp body 51 are inserted, and a lamp. Lamp holders (55) surrounding the bent portion of the body 51 (LAMP HOLDER MIDDLE, 55), the lamp wiring 57 and the lamp wiring 57 connected to both ends of the light source body 51, and supports the lamp wiring ( 57 includes a wire holder (59) for easily withdrawing to the outlet 81 of the lower cover (80).

The light guide plate 60 has a plate shape having a predetermined thickness, and serves to guide light generated from the lamp unit 50 to the rear surface of the liquid crystal panel 20. When the light guide plate 60 flows due to an external impact, the lamp body 51 may be damaged. In addition, noise may occur due to the flow of the light guide plate 50.

In order to solve this problem, a structure for stably supporting the light guide plate 60 is essential.

Conventionally, as illustrated in FIG. 1B, the light guide plate 50 is supported by using a lamp unit 50 formed along the side surface of the light guide plate 60. Specifically, the left and right flow of the light guide plate 60 is restricted by using the wiring holder 59, which is a plastic structure, as shown in FIG. 1B, and the lamp holder 53, which is a plastic structure, as shown in FIG. Up, down, left, and right flow of the light guide plate 60 was limited, and up, down, left, and right flow of the light guide plate 60 were limited by using the lamp holders 55 which are plastic structures as shown in FIG.

However, the above-described structure has a problem in that the lamp holder 53, the lamp holders 55, and the wiring holder 59 are required to increase the manufacturing cost. In addition, it takes a long time to assemble the lamp unit 50 and the light guide plate 60, there is a problem that the productivity of the product is lowered.

Accordingly, an object of the present invention is to provide a liquid crystal display device having a structure capable of supporting the light guide plate effectively and stably while reducing the manufacturing cost.

The above object is, according to the present invention, a liquid crystal panel; A light guide plate positioned behind the liquid crystal panel; A liquid crystal display device comprising a light guide plate, a bottom portion and a side portion extending upwardly from the bottom portion, wherein the bottom portion is formed with a rib supporting a side of the light guide plate.

Here, the rib may be formed by cutting one region of the bottom portion and then bending the cut portion upward.

The bottom portion is provided in a substantially rectangular shape, and the ribs may be formed at edges of four sides of the bottom portion, respectively.

In addition, it is preferable that the distance between the ribs facing each other is substantially the same as the width of the light guide plate in order to stably support the light guide plate.

Here, the rib may be provided to support the end portion in the longitudinal direction of the side of the light guide plate.

And, the rib may be provided at a position corresponding to the end of the side portion of the lower cover.

The light source may further include a light source disposed between one side of the light guide plate and the rib, and the light source may be a light emitting diode.

The above object is, according to the present invention, a liquid crystal panel; A light guide plate positioned on a rear surface of the liquid crystal panel; A light source positioned at one side of the light guide plate to supply light to the rear surface of the liquid crystal panel; And a bottom cover including a bottom portion on which the light guide plate and the light source are seated, and a side portion bent upwardly from the bottom portion, wherein the bottom cover includes ribs supporting both ends of the side surfaces of the light guide plate. Is achieved.

Here, the rib may be formed by cutting one region of the bottom portion and then bending the cut portion upward.

The lower cover may include a rib and a cutting hole formed by cutting the rib, and the cutting hole may be provided at a position overlapping the light guide plate.

In addition, the lower cover may include a rib and a cutting hole formed by cutting the rib, and the cutting hole may be provided at a position not overlapping the light guide plate.

The cut hole may be provided between the side portion and the side surface of the light guide plate.

In addition, the distance between the ribs facing each other may be substantially the same as the width of the light guide plate.

In addition, a soft support layer may be formed on a surface of the rib.

Hereinafter, a liquid crystal display according to a first embodiment of the present invention will be described in detail with reference to the accompanying drawings. In the following description, a case where a light emitting diode (LED) is applied as a light source will be described as an example. However, the present invention is not limited thereto, and the technical concept of the present invention may be applied to the case where the fluorescent lamp is applied as the light source.

As shown in FIG. 2, the liquid crystal display device 100 includes a liquid crystal panel 120 for forming an image, a mold frame 130 supporting an edge of the liquid crystal panel 120, and a mold frame 130. The optical sheet 140 disposed at the rear of the light guide plate, the light guide plate 150 disposed at the rear of the optical sheet 140, the light source 160 disposed at the side surface of the light guide plate 150, and the light guide plate ( Reflecting sheet 170 disposed at the rear of the 150 and the upper cover 110 and the lower cover 180 are coupled to each other and accommodate them therein.

The upper cover 110 is a structure that supports the front edge of the liquid crystal panel 120. The upper cover 110 is formed with a display window that exposes the effective surface (display area) of the liquid crystal panel 120. And, the side of the upper cover 110 is provided with a coupling means such as a hook (not shown) for coupling with the lower cover 170 to be described later.

The liquid crystal panel 120 is injected between the thin film transistor substrate 121, the color filter substrate 122 attached to face the thin film transistor substrate 121, and the thin film transistor substrate 121 and the color filter substrate 122. It includes a liquid crystal (not shown). The liquid crystal panel 120 is arranged in a matrix form of the liquid crystal cells forming a pixel unit, and forms an image by adjusting the light transmittance of the liquid crystal cells in accordance with the image signal information transmitted from the driver (not shown). The liquid crystal panel 120 is generally provided in a rectangular shape having a long side and a short side.

A plurality of gate lines and a plurality of data lines are formed in a matrix form on the thin film transistor substrate 121, and a thin film transistor (TFT) is formed at an intersection point of the gate line and the data line. The signal voltage transmitted from the driver (not shown) is applied between the pixel electrode and the common electrode of the color filter substrate 122 to be described later through the thin film transistor, and the liquid crystal between the pixel electrode and the common electrode is aligned according to the signal voltage. The light transmittance is determined.

The color filter substrate 122 includes a color filter and a common electrode in which red, green, and blue are repeatedly formed on the black matrix. The common electrode is made of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO). The color filter substrate 122 has a smaller area than the thin film transistor substrate 121.

The mold frame 130 is formed along the edge of the liquid crystal panel 120, and has a substantially rectangular ring shape. The mold frame 130 supports the liquid crystal panel 120 spaced apart from the optical sheets 140. The mold frame 130 accommodates the optical sheet 140, the light guide plate 150, the light source 160, and the reflective sheet 170 therein in combination with the lower cover 180 to be described later.

The optical sheet 140 includes a protective sheet 141, a prism sheet 143, and a diffusion sheet 145 positioned on the rear surface of the liquid crystal panel 120. Although not shown, the diffusion sheet 145 is made of a base plate and a bead-shaped coating layer formed on the base plate. The diffusion sheet 145 diffuses the light from the light source unit 160 and supplies the light to the liquid crystal panel 120. The diffusion sheet 145 may be used by overlapping two or three sheets. Although not shown, the prism sheet 143 is formed with a triangular prism shaped prism on the upper surface with a constant arrangement. The prism sheet 143 collects light diffused from the diffusion sheet 145 in a direction perpendicular to the plane of the upper liquid crystal panel 120. The light passing through the prism sheet 143 almost passes vertically to provide a uniform luminance distribution. The uppermost protective sheet 141 protects the prism sheet 143 that is weak to scratches.

The light guide plate 150 is disposed on the rear surface of the liquid crystal panel 120 to guide light generated from the light source 160 to the rear surface of the liquid crystal panel 120. The light guide plate 150 has a pattern such that an incident surface receiving light from the light source 160, an exit surface facing the rear surface of the liquid crystal panel 120, and light irradiated from the light source 160 to the entrance surface proceed to the exit surface. Has a rear surface formed. The back surface faces the reflective sheet 170. As a result, the light guide plate 150 converts the light irradiated from the light source 160 disposed adjacent to the incident surface into planar light to be uniformly transmitted to the liquid crystal panel 120 through the exit surface. In general, the light guide plate 150 is manufactured in a rectangular shape having a long side and a short side. Meanwhile, in another embodiment, the light guide plate 150 may be provided in a wedge shape in which the thickness of the light guide plate 150 decreases as it moves away from one side to the other side.

Light sources 160 are disposed on both long sides of the light guide plate 150 facing each other. As shown in FIG. 3, the light source 160 according to the present invention is disposed between the rib 183 and the light guide plate 150 to be described later. The light source 160 includes a circuit board 161 and a light emitting diode 162 mounted on the circuit board 161. The circuit board 161 has a plate shape extending in one direction and is disposed along the long side of the light guide plate 150. A plurality of light emitting diodes 162 are mounted on the circuit board 161, and circuit wirings are provided to transfer power received from a light source driver (not shown) to the light emitting diodes 162. The light emitting diodes 162 supply white light to the light guide plate 150 and are disposed at regular intervals. Each of the light emitting diodes 162 may include sub light emitting diodes emitting red, green, and blue light, respectively, and light supplied from the sub light emitting diodes is mixed to supply white light. The light emitting diode 162 receives power from a light source driver (not shown) through the circuit board 161.

The reflective sheet 170 is disposed under the light guide plate 150. The reflective sheet 170 reflects light incident to the lower part of the light guide plate 150 among the light from the light emitting diode 162 so as to face upward. The reflective sheet 170 may be made of polyethylene terephthalate (PET) or polycarbonate (PC), and may be coated with silver or aluminum.

Although not shown, the liquid crystal display device 100 may further include a heat sink, a heat dissipation fin, and a heat dissipation fan to remove heat generated from the light emitting diode 162.

The optical sheet 140, the light guide plate 150, the light source 160, and the reflective sheet 170 are accommodated in the mold frame 130 and the lower cover 180 which are coupled to each other. The lower cover 180 includes a bottom portion 181 on which the reflective sheet 170 is seated, and a side portion 182 that is bent from the bottom portion 181 and upwardly extended. As shown in FIGS. 3 and 4, the bottom portion 181 is provided with a plurality of ribs 183 supporting the side surface of the light guide plate 150 accommodated therein.

As shown in FIG. 4, the rib 183 is formed by cutting a region of the bottom portion 181 and then bending the cut portion upward. Therefore, the bottom portion 181 is formed with a cutting hole 184 formed by cutting the rib 183. Here, the cutout 184 is provided in an area overlapping the light guide plate 150 and the reflective sheet 170. That is, the rib 183 is bent from the inner side to the outer side in the cut state.

As shown in FIG. 3, the ribs 183 are formed at positions corresponding to the end portions of the side portions 182 among the four side edges of the bottom portion 181. That is, the rib 183 which concerns on this invention is provided so that the both ends of the long side (length direction) of the light guide plate 150 side surface may be provided. As a result, side surfaces of the corner regions of the light guide plate 150 are supported by the ribs 183, respectively. The distance between the ribs 183 facing each other is substantially the same as the width of the light guide plate 150. Specifically, the width of the short side of the light guide plate 150 is substantially the same as the distance between the ribs 183 provided at the short side of the bottom part 181, and the width of the long side of the light guide plate 150 is the long side of the bottom part 181. It is substantially the same as the distance between the ribs 183 provided in the.

By the lower cover 180 having such a structure, the light guide plate 150 is stably supported by the ribs 183 with limited up, down, left, and right flows. In particular, compared to the prior art, there is no need to use a separate lamp holder, lamp holders and wiring holder, it is possible to reduce the manufacturing cost. In addition, since the rib 183 can be easily formed by cutting and bending a region of the bottom portion 181 after the lower cover 180 is formed, a manufacturing time and an assembly time of the liquid crystal display device 100 are required. Can shorten the productivity of the product can be improved. In particular, when the light emitting diode 162 is used as a light source, it is difficult to stably support the light guide plate 150 because a separate lamp holder, lamp holders and wiring holders are not used, but according to the present invention, the light emitting diode Even when 162 is used as a light source, the light guide plate 150 may be stably supported.

Hereinafter, the second and third embodiments of the present invention will be described with reference to FIGS. 5 and 6. In the second embodiment and the third embodiment, only portions distinguished from the first embodiment will be described and described, and the description thereof will be omitted or summarized according to the first embodiment and known techniques. In addition, for the convenience of description, the same reference numerals are assigned to the same components to be described.

5 is a view for explaining a light guide plate support structure of a liquid crystal display according to a second exemplary embodiment of the present invention.

The rib 183 according to the second embodiment is formed by bending in the inward direction from the outside in the cut state. That is, as shown in FIG. 5, in the opposite direction to the first embodiment, the cutout 184 is provided in an area which does not overlap the light guide plate 150 and the reflective sheet 170. The cutting hole 184 is provided between the side portion 182 and the side surface of the light guide plate 150.

Due to this structure, some of the plurality of cutouts 184 are positioned under the light source 160. Here, the cutting hole 184 is a passage for emitting heat generated from the light source 160 to the outside. As a result, the heat radiation efficiency of the liquid crystal display device is improved. In particular, it is more effective when using a light source with a large heat dissipation, such as a light emitting diode.

On the other hand, although the light leakage caused by the cut-out hole 184 or the light efficiency may be concerned, although not shown in detail, the light source 160 is a part of the light source 160 is wrapped by a light source cover (not shown) Because of this, it is possible to minimize the generation of light leakage or degradation of light efficiency.

6 is a view for explaining a light guide plate support structure of a liquid crystal display according to a third embodiment of the present invention.

As shown in FIG. 6, the surface of the rib 183 is applied by a soft support layer 185. The support layer 185 is formed by coating an elastic or soft material such as silicon or rubber on the rib 183 surface.

The reason for providing a separate support layer 185 is as follows. When the lower cover 180 includes a metal component, interference may occur between the rib 183 and the side surface of the light guide plate 150 due to external impact, and thus an appearance defect such as a scratch may occur on the light guide plate 150. In addition, when the light guide plate 150 is not closely fixed, a friction sound between the rib 183 and the light guide plate 150 may be generated by external impact. In order to solve this problem, the light guide plate 150 is stably supported by the support layer 185 by forming a support layer 185 by coating a soft material on the surface of the rib 183. In addition, it is possible to absorb the interference and impact between the rib 183 and the light guide plate 150 due to the external impact.

As described above, according to the present invention, it is possible to provide a liquid crystal display device having a structure capable of supporting the light guide plate effectively and stably while reducing the manufacturing cost.

Claims (15)

A liquid crystal panel; A light guide plate positioned behind the liquid crystal panel; It accommodates the light guide plate, and includes a bottom portion and a side portion extending upward from the bottom portion, And a rib supporting a side surface of the light guide plate accommodated in the bottom portion. The method of claim 1, And the rib is formed by cutting a region of the bottom portion and then bending the cut portion upward. The method of claim 1, The bottom portion is provided in a substantially rectangular shape, And the ribs are formed at edges of four sides of the bottom portion, respectively. The method of claim 3, And the distance between the ribs facing each other is substantially the same as the width of the light guide plate. The method of claim 1, And the rib is provided to support an end portion in the longitudinal direction of the side surface of the light guide plate. The method of claim 1, And the rib is provided at a position corresponding to an end portion of the side portion of the lower cover. The method of claim 1, And a light source disposed between one side of the light guide plate and the rib. The method of claim 7, wherein And the light source is a light emitting diode. A liquid crystal panel; A light guide plate disposed on a rear surface of the liquid crystal panel; A light source positioned at one side of the light guide plate to supply light to a rear surface of the liquid crystal panel; A lower cover including a bottom part on which the light guide plate and the light source are seated, and a side part bent upward from the bottom part, And the lower cover includes ribs for supporting both ends of side surfaces of the light guide plate. The method of claim 9, And the rib is formed by cutting a region of the bottom portion and then bending the cut portion upward. The method of claim 10, The lower cover includes the rib and the cutting hole formed by cutting the rib, And the cut-out hole is provided at a position overlapping with the light guide plate. The method of claim 10, The lower cover includes the rib and the cutting hole formed by cutting the rib, And the cutout is provided at a position not overlapping with the light guide plate. The method of claim 12, And the cutout is provided between the side portion and the side surface of the light guide plate. The method according to claim 11 or 13, And the distance between the ribs facing each other is substantially equal to the width of the light guide plate. The method of claim 14, And a soft support layer is formed on the surface of the rib.

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