KR20080049465A - Backlight unit and liquid crystal display having the same - Google Patents

Abstract

A backlight unit and an LCD(Liquid Crystal Display) having the same are provided to prevent a flow of a panel guide by enabling the panel guide to be locked with the bottom cover when external force is induced, thereby preventing wrinkles of an optical sheet caused by the external force. An optical member(130) changes a path of light emitted from a lamp(120). A bottom cover(140) includes a bottom unit(142), a first side unit(144) prolonged from the bottom, and a protrusion unit(147) protruded from the first side unit. The bottom cover receives the lamp and the optical member in a receiving space prepared in the bottom unit and the first side unit. A panel guide(150) includes a second side unit(152) for surrounding the first side unit of the bottom cover, a fixing unit(154) inwardly formed from the second side unit, and a locking unit(156) formed in a location corresponding to the protrusion unit. The panel guide is fastened with the bottom cover. Therefore, the locking unit is locked with the protrusion unit when external force is induced.

Description

BACKLIGHT UNIT AND LIQUID CRYSTAL DISPLAY HAVING THE SAME}

1 is a cross-sectional view illustrating a conventional backlight unit.

2 is an exploded perspective view illustrating a backlight unit according to an exemplary embodiment of the present invention.

3 is a cross-sectional view taken along line III-III ′ of FIG. 2.

4 is an enlarged perspective view illustrating the bottom cover and the panel guide of FIG. 2 before fastening.

FIG. 5 is a cross-sectional view taken along the line VV ′ of FIG. 4.

6 is an enlarged perspective view illustrating the bottom cover and the panel guide of FIG. 2 after being fastened.

FIG. 7 is a cross-sectional view taken along the line VII-VII 'of FIG. 6.

FIG. 8 is an exploded perspective view illustrating a liquid crystal display including the backlight unit of FIG. 2.

FIG. 9 is a cross-sectional view taken along the line VII-VII 'of FIG. 8.

{Description of symbols for main parts of the drawing}

100: liquid crystal display 110: backlight unit

120: lamp 130: optical member

140: bottom cover 142: bottom

144: first side 147: protrusion

148: body portion 149: bending portion

150: panel guide 152: second side

154: fixing portion 156: locking portion

160: liquid crystal panel

The present invention relates to a backlight unit and a liquid crystal display having the same.

As information technology develops, the demand for display devices, which is a connection medium between humans and information, is increasing. Accordingly, flat panel displays (FPDs) such as liquid crystal displays (LCDs), organic light emitting diodes (OLEDs), and plasma display panels (PDPs) may be used. Usage is increasing. Among them, a liquid crystal display capable of realizing high resolution and capable of miniaturization as well as a large size is widely used.

In general, liquid crystal displays display images using the electro-optical properties of liquid crystals. To this end, the liquid crystal display includes a liquid crystal panel and a backlight unit.

The liquid crystal panel displays an image using light provided from the backlight unit.

The backlight unit provides light to the liquid crystal panel. The backlight unit is divided into a direct type and an edge type according to the lamp arrangement.

The direct type backlight unit refers to a backlight unit in which at least one lamp is disposed on the rear surface of the liquid crystal panel. In the direct type backlight unit, as described above, the lamp is disposed on the rear surface of the liquid crystal panel so that the light emitted from the lamp is directly provided to the liquid crystal panel without the help of the light guide plate. The direct type backlight unit can use a larger number of lamps than the edge type backlight unit, and thus is mainly used in a large liquid crystal display device requiring high brightness.

An edge type backlight unit refers to a backlight unit in which a lamp is disposed adjacent to a side of a liquid crystal panel. The light emitted from the lamp in the edge type backlight unit is guided by a transparent light guide plate formed on the rear surface of the liquid crystal panel and then provided to the liquid crystal panel. The edge type backlight unit is mainly used in small and medium sized liquid crystal displays because it is advantageous in thinning.

As described above, the backlight unit may be classified into a direct type and an edge type, but the following description will be given by taking an edge type backlight unit as an example.

1 is a cross-sectional view illustrating a conventional backlight unit.

Referring to FIG. 1, the conventional backlight unit 10 includes a lamp 20, an optical member 30, a bottom cover 40, and a panel guide 50.

The lamp 20 is driven by a power source provided from the inverter to generate light. The lamp 20 is formed at least one along the longitudinal direction of one side of the light guide plate (32). Here, the light emitted from the lamp 20 is incident directly into the light guide plate 32, or is formed along the longitudinal direction of the lamp 20 and reflected by the lamp housing 22 surrounding a part of the lamp 20 The light guide plate 32 may be incident into the light guide plate 32.

The optical member 30 changes the path of the light emitted from the lamp 20 to improve the efficiency of the light. To this end, the optical member 30 includes a light guide plate 32, a reflector 34, and an optical sheet 36.

The light guide plate 32 is disposed on the side of the lamp 20 and guides the light emitted from the lamp 20 and incident on the light guide plate 32, and then emits the light upward.

The reflector 34 is disposed under the light guide plate 32, and reflects light leaked downward through the light guide plate 32 among light emitted from the lamp 20 toward the light guide plate 32, that is, upward.

The optical sheet 36 is disposed above the light guide plate 32 and diffuses and / or condenses the light emitted upward through the light guide plate 32 among the light emitted from the lamp 20.

The bottom cover 40 houses the lamp 20 and the optical member 30. For this purpose, the bottom cover 40 includes a bottom portion 42 and a first side portion 44. Here, the first side portion 44 extends from the bottom portion 42 and forms an accommodating space for accommodating the lamp 20 and the optical member 30 together with the bottom portion 42.

The panel guide 50 is formed to surround the first side 44 of the bottom cover 40 and prevents the flow of the optical member 30. To this end, the panel guide 50 includes a second side portion 52 and a fixing portion 54. Here, the second side portion 52 is formed to surround the first side portion 44. In addition, the fixing portion 54 is formed inward from the second side portion 52 to fix the edge of the optical member 30.

The conventional backlight unit 10 having the above configuration is formed so that the panel guide 50 simply surrounds the first side portion 44 of the bottom cover 40, so that the panel guide 50 may be introduced when external force such as vibration or shock is introduced. Can easily flow.

That is, when the external force is introduced, the second side portion 52 of the panel guide 50 may be spaced apart from the first side portion 44 of the bottom cover 40. For this reason, there arises a problem that the optical member 30 may not be fixed by the panel guide 50 flowing when the external force flows. In particular, when the external force is introduced, there is a problem that the optical sheet 36 disposed at the top of the optical member 30 may not be fixed by the panel guide 50 that flows.

On the other hand, after the external force is removed, the panel guide 50 is restored, but the panel guide 50 pushes the optical sheet 36 inward direction during restoration. For this reason, the optical sheet 36 cannot be fixed and wrinkles may arise. As a result, appearance quality and display quality of the backlight unit 10 and the liquid crystal display including the same may be degraded.

Accordingly, an object of the present invention is to provide a backlight unit capable of preventing the flow of the panel guide when an external force is introduced by changing the structure of the bottom cover and the panel guide, and a liquid crystal display having the same.

In addition, another technical problem to be achieved by the present invention is to provide a backlight unit and a liquid crystal display having the same that can prevent wrinkles of the optical sheet caused by the external force by changing the structure of the bottom cover and the panel guide.

In addition, another technical problem to be achieved by the present invention is to provide a backlight unit that can improve the appearance quality and display quality by preventing the wrinkle of the optical sheet caused by the external force by changing the structure of the bottom cover and panel guide and It is to provide a liquid crystal display device.

Further technical problems to be achieved by the present invention are not limited to the above-mentioned technical problems, and other technical problems not mentioned above are clearly understood by those skilled in the art from the following description. It can be understood.

The backlight unit according to the present invention for achieving the above technical problem, the lamp; An optical member for changing a path of light emitted from the lamp; A bottom portion, a first side portion extending from the bottom portion, and a protrusion portion protruding from the first side portion, and storing the lamp and the optical member in an accommodation space provided by the bottom portion and the first side portion. Bottom cover; And a second side portion formed to surround the first side portion of the bottom cover, a fixing portion formed inwardly from the second side portion, and a locking portion formed at a position corresponding to the protrusion, and engaged with the bottom cover, when external force is introduced. The locking portion includes a panel guide formed to hook the protrusion.

Here, the protrusion of the panel guide, the body portion is formed to protrude from the upper portion of the first side of the bottom cover, so that the engaging portion is caught when the external force is introduced; And a banding part extending from an upper portion of the body part and formed to be bent relative to the body part.

Here, the body portion, characterized in that the edge of the body portion is chamfered with respect to the upper portion of the first side portion.

Here, the bending portion is bent in the outward direction with respect to the body portion, characterized in that the contact with the engaging portion.

Here, the engaging portion of the panel guide, characterized in that formed in the predetermined area of the second side portion and the fixing portion cut.

On the other hand, the liquid crystal display device according to the present invention for achieving the above technical problem, the lamp; An optical member for changing a path of light emitted from the lamp; A bottom portion, a first side portion extending from the bottom portion, and a protrusion portion protruding from the first side portion, and storing the lamp and the optical member in an accommodation space provided by the bottom portion and the first side portion. Bottom cover; A second side part formed to surround the first side part of the bottom cover, a fixing part formed inwardly from the second side part, and a locking part formed at a position corresponding to the protrusion part, and engaged with the bottom cover, A panel guide formed so that the locking portion is caught by the protrusion; And a liquid crystal panel mounted on the panel guide and displaying an image using the light.

Specific details of other embodiments are included in the detailed description and the drawings. Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings.

Hereinafter, a backlight unit and a liquid crystal display having the same according to an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings.

2 is an exploded perspective view illustrating a backlight unit according to an exemplary embodiment of the present invention, and FIG. 3 is a cross-sectional view taken along line III-III ′ of FIG. 2.

2 and 3, the backlight unit 110 according to the embodiment of the present invention includes a lamp 120, an optical member 130, a bottom cover 140, and a panel guide 150.

The lamp 120 is driven by the power supplied from the inverter to generate light. The lamp 120 may be formed in at least one or more along the longitudinal direction of one side of the light guide plate 132, or at least two or more along the longitudinal direction of both sides of the light guide plate 132, but is not limited thereto.

Herein, the light emitted from the lamp 120 is directly incident into the light guide plate 132, or is formed along the longitudinal direction of the lamp 120 and reflected by the lamp housing 122 surrounding a part of the lamp 120. The light guide plate 132 may be incident into the light guide plate 132.

The lamp 120 includes a cold cathode fluorescent lamp (CCFL), a hot cathode fluorescent lamp (HCFL), an external electrode fluorescent lamp (EEFL), and a light emitting diode (Light). Emitting Diode (LED), but is not limited thereto.

The optical member 130 changes the path of the light emitted from the lamp 120 to improve the efficiency of the light. To this end, the optical member 130 includes a light guide plate 132, a reflective plate 134, and an optical sheet 136.

The light guide plate 132 is disposed on the side of the lamp 120 and guides the light emitted from the lamp 120 and then incident to the light guide plate, and then emits the light upward.

The reflection plate 134 is disposed under the light guide plate 132, and reflects light leaked downward through the light guide plate 132 of the light emitted from the lamp 120 toward the light guide plate 132, that is, upward. To this end, the surface of the reflector 134 may be formed of a material having a high reflectance.

The optical sheet 136 is disposed above the light guide plate 132 and diffuses and / or condenses light emitted upward through the light guide plate 132 among the light emitted from the lamp 120. For this purpose, the optical sheet 136 may be composed of at least two or more of the diffusion sheet, the prism sheet and the brightness enhancement sheet.

The bottom cover 140 accommodates the lamp 120 and the optical member 130. In addition, the bottom cover 140 prevents the flow of the panel guide 150 by engaging the panel guide 150 when the external force is introduced, such as shock or vibration. To this end, the bottom cover 140 may include a bottom portion 142, a first side portion 144, and a protrusion 147.

The first side portion 144 extends from the bottom portion 142 and forms an accommodating space for accommodating the lamp 120 and the optical member 130 together with the bottom portion 142.

In the first side portion 144, a locking jaw 145 and a fastening hole 146 may be formed at a position adjacent to the protrusion 147. This is to fasten the top cover fixing the liquid crystal panel with the bottom cover 140 in the liquid crystal display having the backlight unit 110.

That is, the hook formed on the inner surface of the top cover at a position corresponding to the fastening hole 146 is inserted into the fastening hole 146, so that the top cover may be fastened to the bottom cover 140. At this time, the locking jaw 145 serves to prevent the hook from coming off the fastening hole 146 after the top cover and the bottom cover 140 are fastened.

The protruding portion 147 protrudes from an upper portion of the first side portion 144, and catches the catching portion 156 of the panel guide 150 when an external force is introduced.

The bottom cover 140 having the above configuration may be formed through press working with a metal material, but is not limited thereto.

The panel guide 150 is coupled to the bottom cover 140 to prevent the flow of the optical member 130. In addition, the panel guide 150 is prevented from flowing by engaging the bottom cover 140 when the external force is introduced. To this end, the panel guide 150 includes a second side portion 152, a fixing portion 154, and a locking portion 156.

The second side 152 is formed to surround the first side 144. For this reason, the panel guide 150 is disposed outside the bottom cover 140 when the bottom guide 140 is fastened to the bottom cover 140.

The fixing part 154 is formed inward from the second side part 152 to fix the edge of the optical member 130. The fixing part 154 is formed to have a rectangular frame shape with an open center. Meanwhile, the liquid crystal panel may be mounted on the fixing part 154.

The locking portion 156 is formed at a position corresponding to the protrusion 147 and is caught by the protrusion 147 when an external force is introduced.

The panel guide 150 having the above configuration may be formed by injection of a mold material, but is not limited thereto.

On the other hand, the protrusion 147 of the bottom cover 140 and the locking portion 156 of the panel guide 150 will be described in more detail with reference to FIGS. 4 to 7.

4 is an enlarged perspective view illustrating the bottom cover and the panel guide of FIG. 2 before being fastened, FIG. 5 is a cross-sectional view taken along the line VV ′ of FIG. 4, and FIG. 6 is a bottom cover and the panel guide of FIG. 2. Is an enlarged perspective view showing after the fastening, and FIG. 7 is a cross-sectional view taken along the line VII-VII 'of FIG.

4 to 7, the panel guide 150 is fastened to the bottom cover 140 in a top down manner from an upper side of the bottom cover 140. At this time, as described above, the protrusion 147 of the bottom cover 140 when the external force is introduced to catch the engaging portion 156 of the panel guide 150 to prevent the flow of the panel guide 150. To this end, the protrusion 147 of the bottom cover 140 includes a body portion 148 and a bending portion 149.

The body portion 148 is formed to protrude from the upper portion of the first side portion 144, so that the catching portion 156 is caught by itself when the external force is introduced. The edge of the body portion 148 may be chamfered with respect to the upper portion of the first side portion 144. This is to strengthen the rigidity of the protrusion 147.

The bending portion 149 extends from the top of the body portion 148 and is formed to be bent relative to the body portion 148. Due to the bending part 149, the rigidity of the protrusion 147 may be further enhanced. Here, the bending portion 149 may be formed to be bent outward with respect to the body portion 148 so as not to contact the locking portion 156. This is to prevent the panel guide 150 from being scratched by the protrusion 147 when the bottom cover 140 and the panel guide 150 are fastened.

That is, a burr may be formed in the bending portion 149 due to the bottom cover 140 made of a metal material. Such burrs may scratch the panel guide 150 which is a mold material when the bottom cover 140 and the panel guide 150 are fastened. As a result, foreign matter may be generated, and display quality and appearance quality of the backlight unit 110 and the liquid crystal display including the same may be degraded. In order to prevent this, the bending portion 149 is formed to be bent outward with respect to the body portion 148, so that the bending portion 149 is caught when the bottom cover 140 and the panel guide 150 are fastened. You can avoid contact with

The locking portion 156 of the panel guide 150 may be formed by cutting a predetermined area of the second side portion 152 and the fixing portion 154 of the panel guide 150. For this reason, the locking portion 156 may be formed inward with respect to the protrusion 147.

8 is an exploded perspective view illustrating a liquid crystal display including the backlight unit of FIG. 2, and FIG. 9 is a cross-sectional view taken along the line VII-VII of FIG. 8. 8 and 9 are the same as the detailed description of FIGS. 2 to 7 and therefore use the same reference numerals, and only their features will be described.

8 and 9, the liquid crystal display 100 according to the exemplary embodiment of the present invention displays an image by using the electro-optical characteristics of the liquid crystal. To this end, the liquid crystal display 100 includes a backlight unit 110 and a liquid crystal panel 160.

The liquid crystal panel 160 is mounted on the panel guide 150 and is fixed by the top cover 190 fastened to the bottom cover 140. As described above, the top cover 190 may be fastened to the bottom cover 140 by being inserted into the fastening hole 146 of the bottom cover 140 by the hook 192 formed on its inner surface.

The liquid crystal panel 160 displays an image by using the light emitted from the lamp 120. To this end, the liquid crystal panel 160 includes a color filter substrate 162 and a thin film transistor substrate 164 facing each other with the liquid crystal interposed therebetween.

The color filter substrate 162 represents the color of the liquid crystal panel 160. To this end, the color filter substrate 162 includes an array of color filters, eg, red / green / blue color filters, formed in a thin film on a transparent substrate such as glass or plastic.

The thin film transistor substrate 164 is electrically connected to the printed circuit board 180 through the driving film 170. The thin film transistor substrate 164 applies a driving voltage provided from the printed circuit board 180 to the liquid crystal in response to a driving signal provided from the printed circuit board 180. To this end, the thin film transistor substrate 164 includes a thin film transistor, a pixel electrode, and a common electrode formed of a thin film on a transparent substrate such as glass or plastic. Here, the common electrode may be formed on the color filter substrate 162.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, those skilled in the art to which the present invention pertains can realize that the present invention can be implemented in other specific forms without changing the technical spirit or essential features. I can understand that.

Therefore, since the embodiments described above are provided to completely inform the scope of the invention to those skilled in the art, it should be understood that they are exemplary in all respects and not limited. The invention is only defined by the scope of the claims.

In the backlight unit and the liquid crystal display having the same according to the present invention as described above, the flow of the panel guide may be prevented by the panel guide being caught by the bottom cover when an external force is introduced. For this reason, the wrinkle of the optical sheet which arises due to an external force can be prevented. For this reason, the appearance quality and display quality of a backlight unit and a liquid crystal display provided with the same can be improved.

In addition, since the panel guide is not damaged by the bottom cover when the bottom cover and the panel guide are fastened, the appearance quality and the display quality of the backlight unit and the liquid crystal display including the same may be improved.

Claims (10)

lamp; An optical member for changing a path of light emitted from the lamp; A bottom portion, a first side portion extending from the bottom portion, and a protrusion portion protruding from the first side portion, and storing the lamp and the optical member in an accommodation space provided by the bottom portion and the first side portion. Bottom cover; And A second side part formed to surround the first side part of the bottom cover, a fixing part formed inwardly from the second side part, and a locking part formed at a position corresponding to the protrusion part, and engaged with the bottom cover, Panel guide formed to engage the projection A backlight unit comprising a. The method of claim 1, wherein the protrusion of the panel guide, A body portion protruding from an upper portion of the first side portion of the bottom cover, such that the locking portion is caught when the external force is introduced; And A bending portion formed extending from an upper portion of the body portion and being bent relative to the body portion; A backlight unit comprising a. The method of claim 2, The body unit, wherein the edge of the body portion is chamfered with respect to the upper portion of the first side portion. The method of claim 2, The bending unit is bent in the outward direction with respect to the body portion, characterized in that the backlight unit is not in contact with the locking portion. The method of claim 1, The locking unit of the panel guide is formed by cutting a predetermined area of the second side part and the fixing part. lamp; An optical member for changing a path of light emitted from the lamp; A bottom portion, a first side portion extending from the bottom portion, and a protrusion portion protruding from the first side portion, and storing the lamp and the optical member in an accommodation space provided by the bottom portion and the first side portion. Bottom cover; A second side part formed to surround the first side part of the bottom cover, a fixing part formed inwardly from the second side part, and a locking part formed at a position corresponding to the protrusion part, and engaged with the bottom cover, A panel guide formed so that the locking portion is caught by the protrusion; And A liquid crystal panel mounted on the panel guide and displaying an image using the light. Liquid crystal display comprising a. The method of claim 6, wherein the protrusion of the panel guide, A body portion protruding from an upper portion of the first side portion of the bottom cover, such that the locking portion is caught when the external force is introduced; And A bending portion formed extending from an upper portion of the body portion and being bent relative to the body portion; Liquid crystal display comprising a. The method of claim 7, wherein And the edge portion of the body portion is chamfered with respect to an upper portion of the first side portion. The method of claim 7, wherein And the bending portion is bent in an outward direction with respect to the body portion so as not to contact the locking portion. The method of claim 6, The locking part of the panel guide is formed by cutting a predetermined area of the second side part and the fixing part.

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