KR20070088088A - Back light unit and liquid crystal display including the same - Google Patents

Abstract

A backlight unit and an LCD(Liquid Crystal Display) including the same are provided to improve uniformity of light emitted from a lamp and applied to a light guide panel by firmly coupling a lamp assembly with a cover bottom. A light guide panel(325) guides light applied from a lamp(321). A lamp assembly(323) receives the lamp and includes at least one protrusion protruding from an outer surface. A cover bottom(340) includes a groove or a hole corresponding to the protrusion of the lamp assembly, and receives the lamp assembly in a space with the light guide panel. The protrusion of the lamp assembly and the groove or the hole of the cover bottom correspond to each other, and are formed in central areas of the lamp assembly and the cover bottom respectively.

Description

Back light unit and liquid crystal display including the same {Back light unit and liquid crystal display including the same}

1 is a partial perspective view for explaining the structure of a backlight unit according to the prior art.

2 is an exploded perspective view and a partially enlarged view of a backlight unit according to an embodiment of the present invention.

FIG. 3 is an exploded view illustrating the liquid crystal display device including the backlight unit of FIG. 2.

<Explanation of symbols on main parts of the drawings>

210, 323: lamp assembly 215: projection

220, 340: Cover Bottom 230: Groove

310: liquid crystal display panel 312: lower substrate

314: upper substrate 320: backlight unit

321: lamp 325: light guide plate

327: optical sheet 330: driving circuit

335 TCP

The present invention relates to a backlight unit and a liquid crystal display device having the same, and more particularly, to a light guide plate type backlight unit having a more robust and improved light uniformity by increasing the fixing force of the lamp assembly and a liquid crystal display device having the same. It is about.

In recent years, liquid crystal displays are spotlighted as display means.

Liquid crystal displays perform display functions using the electrical and optical properties of liquid crystals injected into the liquid crystal display panel. The advantages of small size, light weight, low power consumption, etc. It is widely applied to the trend.

Since the liquid crystal display device is not a self-luminous display device but a light receiving type display device, a separate light source such as a back light unit equipped with a lamp is required. That is, by selectively transmitting the light applied from the backlight unit through the liquid crystal display panel, desired image information can be displayed.

The backlight unit may be classified into a light guide plate type and a light guide plate type according to the presence or absence of the light guide plate. The backlight unit may include a lamp, an optical sheet, a reflective plate, and the like separately from the presence or absence of the light guide plate.

1 is a partial perspective view illustrating the structure of a backlight unit according to the prior art, in particular showing a light guide plate type backlight unit.

Referring to FIG. 1, it can be seen that the backlight unit according to the related art includes a lamp assembly 110, a light guide plate 120, a cover bottom 130, and the like.

The lamp assembly 110 receives a lamp (not shown) and is positioned between the side of the light guide plate 120 and the cover bottom 130. The lamp assembly 110 is usually inserted between the light guide plate 120 and the cover bottom 130 and then supported by fixing at both ends thereof.

However, when the lamp assembly 110 is fixedly supported using only both ends thereof, the restraining force of the central portion of the lamp assembly 110 may be relatively weak, such that deflection of the central portion due to bending may occur. The deflection of is getting worse with large liquid crystal display. The central sag phenomenon of the lamp assembly 110 not only facilitates breakage of the lamp when an impact or the like is applied from the outside, but also unevenness of light applied to the liquid crystal display panel due to the unevenness of the gap between the lamp and the light guide plate 120. This causes a problem such as deterioration of the quality of the image information displayed through the liquid crystal display device.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide a light guide plate type backlight unit which is more robust and has improved light uniformity by increasing a fixing force of a lamp assembly, and a liquid crystal display device having the same.

The objects of the present invention are not limited to the above-mentioned objects, and other objects not mentioned will be clearly understood by those skilled in the art from the following description.

In order to achieve the above object, a backlight unit according to an embodiment of the present invention, a lamp, a light guide panel for guiding light applied from the lamp, and receives a lamp from an external surface The lamp assembly includes a lamp assembly having at least one protrusion formed thereon, and a cover bottom having a groove or a hole corresponding to the protrusion of the lamp assembly and receiving the lamp assembly in a space between the light guide plate.

In this case, the protrusions of the lamp assembly and the grooves or holes of the cover bottom may be formed in the central regions of the lamp assembly and the cover bottom, respectively.

The lamp assembly may be inserted in close contact with the space between the light guide plate and the cover bottom, and may be fixedly supported by a plurality of coupling means including an uneven coupling by a protrusion and a groove or a hole.

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. However, the present invention is not limited to the embodiments disclosed below, but may be embodied in various forms, and the present embodiments are merely provided to make the disclosure of the present invention complete and the general knowledge in the art to which the present invention belongs. It is provided to fully inform the person having the scope of the invention, the invention is defined only by the scope of the claims. Like reference numerals refer to like elements throughout.

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

2 is an exploded perspective view showing a backlight unit according to an embodiment of the present invention and a partial enlarged view thereof, and shows a structure of a lamp assembly and a cover bottom.

As shown in FIG. 2, the backlight unit according to the exemplary embodiment of the present invention includes a lamp assembly 210, a cover bottom 220, and the like.

The lamp assembly 210 includes a protrusion 215 that receives a lamp therein and protrudes from an outer wall thereof. In this case, the protrusion 215 may be formed at the center of the lamp assembly 210.

The lamp assembly 210 is fixedly positioned by being inserted in close contact with the light guide plate (not shown) and the cover bottom 220.

The cover bottom 220 accommodates the light guide plate and supports the lamp assembly 210 using a space between the accommodated light guide plate and the sidewall of the cover bottom 220. Grooves and / or holes 225 are formed at predetermined positions of the cover bottom 220 corresponding to the protrusions 215 of the lamp assembly 210, and between the protrusions 215 and the grooves and / or holes 225. The lamp assembly 210 may be more firmly fixed by the uneven coupling.

In other words, the lamp assembly 210 inserted into the space between the light guide plate and the cover bottom 220 is first fixed by the uneven coupling by the protrusion 215 and the groove and / or the hole 225 of the central region. Both ends of the lamp assembly 210 are secondly fixed again by screw coupling with a support main (not shown). Therefore, not only the lamp assembly 210 can be more stably fixed and supported by the uniform bonding force as a whole, but also the gap between the lamp assembly 210 and the light guide plate can be maintained as a whole as a whole, thereby providing liquid crystal through the light guide plate. The effect of being able to improve the uniformity of the light applied to the display panel (not shown) can be obtained.

FIG. 3 is an exploded view illustrating the liquid crystal display device including the backlight unit of FIG. 2.

Referring to FIG. 3, a liquid crystal display including a backlight unit according to an exemplary embodiment of the present invention generally has a liquid crystal display panel 310, a backlight unit 320, a driving circuit 330, and a cover bottom. 340) and the like.

The liquid crystal display panel 310 includes a lower substrate 312, an upper substrate 314, and a liquid crystal layer (not shown) formed between the two substrates 312 and 314.

Typically, the lower substrate 312 includes a gate line, a data line, a thin film transistor, a pixel electrode, and the like, and the upper substrate 314 is positioned on the upper side of the lower substrate 312 to face the color filter, the black matrix, and the common electrode. But not shown.

The configuration and operation thereof are briefly described as follows.

First, a plurality of gate lines and data lines are arranged on the lower substrate 312 to have a matrix form of m × n. Thin film transistors, which are switching elements, are formed at intersections of the plurality of gate lines and data lines.

Although not shown in detail, the thin film transistor includes a gate electrode, a source electrode, a drain electrode, an active layer, an ohmic contact layer, and the like, and the drain electrode is connected to the pixel electrode to form a unit pixel. In other words, when the gate signal is applied to the gate electrode through the gate line, the thin film transistor operates to transfer the data signal applied to the data line from the source electrode to the drain electrode through the ohmic contact layer and the active layer.

That is, when a data signal is applied to the source electrode, a voltage corresponding thereto is applied to the pixel electrode connected to the drain electrode, which causes a voltage difference between the pixel electrode and the common electrode. In addition, due to the voltage difference between the pixel electrode and the common electrode, the molecular arrangement of the liquid crystal interposed therebetween changes, and the light transmittance of the pixel changes due to the change in the molecular arrangement of the liquid crystal, thereby changing the data signal applied to each pixel. The color difference of the pixel is generated according to the difference. By using the color difference, the screen of the LCD may be controlled.

The gate signal applied to the gate line and the data signal applied to the data line are generated by driving circuits 330 such as a gate driver and a data driver, respectively, and between the driver circuit 330 and the liquid crystal display panel 310 is TCP. (Tape Carrier Package, 335) or the like. The TCP 335 may be made of a flexible material. In this case, the driving circuit 330 may be positioned on the rear surface of the cover bottom 340 by bending the TCP 335.

In this case, although the color filter, the common electrode, and the like have been described in the upper substrate 314 in general, the common electrode may be formed on the lower substrate 312 in the case of a horizontal alignment type (IPS mode) liquid crystal display device, In the case of a color-filter on array (COA) type liquid crystal display device, the color filter may be formed on the lower substrate 312, which is obvious to those skilled in the art, and thus detailed description thereof will be omitted.

The backlight unit 320 includes a lamp assembly 323, a light guide plate 325, an optical sheet 327, and the like.

The lamp 321 is fixedly positioned inside the lamp assembly 323 to irradiate light to the light guide plate 325, and a lower plate of the light guide plate 325 may further include a reflector for reflecting downward leakage light. I did not.

The light applied to the light guide plate 325 is guided to the optical sheet 327 on the light guide plate 325 by the diffuse reflection by the diffuse reflection pattern or the like inside the light guide plate 325, and then scattered and collected by the optical sheet 327 to form a liquid crystal display. Is applied to the panel 310. The optical sheet 327 may be composed of a diffusion sheet, a prism sheet, and the like.

In this case, the lamp assembly 323 fixedly supporting the lamp 321 includes one or more protrusions protruding from the outer wall of the center portion, and grooves and / or holes are formed in a region corresponding thereto of the cover bottom 340. In addition, the uneven coupling of the protrusions and the grooves and / or holes enables the lamp assembly 323 to be more stably fixed and supported by a uniform bonding force as a whole, and to provide a gap between the lamp assembly 323 and the light guide plate 325. The constant is maintained to improve the uniformity of light applied from the lamp 321 to the light guide plate 325.

In the liquid crystal display described with reference to the embodiment of FIG. 3, the backlight unit 320 is illustrated as a flat light guide plate 325 having lamps on both sides, but the present invention is not limited thereto. Naturally, a wedge-shaped light guide plate or a flat light guide plate having a lamp on one side thereof may be used as the light guide plate provided in the liquid crystal display according to an exemplary embodiment.

The cover bottom 340 constitutes an external shape of the liquid crystal display.

Although not shown in detail, the cover bottom 340 may fix the internal components of the liquid crystal display by fastening with the upper support main (not shown) and configure the overall appearance of the liquid crystal display. In the space between the cover bottom 340 and the light guide plate 325, the lamp assembly 323 is inserted and fixed so as to be in close contact therewith, respectively.

Although 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 may implement the present invention in other specific forms without changing the technical spirit or essential features thereof. I can understand that. Therefore, the embodiments described above are to be understood in all respects as illustrative and not restrictive.

According to the backlight unit of the present invention and the liquid crystal display device having the same as described above, the center portion between the lamp assembly and the cover bottom can be more firmly fixed by uneven coupling or the like.

Accordingly, the central sag of the lamp and the like can be prevented, thereby improving the uniformity of the light irradiated from the lamp and applied to the light guide plate.

In addition, the lamp assembly and the cover bottom may be further brought into close contact with each other, thereby further facilitating heat dissipation of heat generated from the lamp.

Claims (4)

lamp; A light guide panel for guiding light applied from the lamp; A lamp assembly receiving the lamp and having one or more protrusions protruding from an outer surface thereof; And And a groove or a hole corresponding to the protrusion of the lamp assembly, and a cover bottom receiving the lamp assembly in a space between the light guide plate and the light guide plate. The method of claim 1, The projection unit of the lamp assembly and the groove or hole of the cover bottom are respectively formed in the central region of the lamp assembly and the cover bottom so as to correspond. The method of claim 2, The lamp assembly is inserted in close contact with the space between the light guide plate and the cover bottom, and is fixedly supported by a coupling means including a concave-convex coupling by the projection and the groove or hole. unit. A liquid crystal display device comprising the backlight unit according to any one of claims 1 to 3.

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