KR20070039236A - Backlight unit - Google Patents

Abstract

The present invention is to provide a backlight unit suitable for improving the light emitting reliability by preventing the occurrence of partial dark phenomenon, the backlight unit for achieving the above object is a plurality of lamps formed in a 'U' shape on the cover bottom With; A supporter side for guiding it on both sides of the lamp; And a plurality of grooves provided to fix the lamp in the supporter side on one side adjacent to the 'U' shaped portion of the lamp.

Supporter side, groove, U-shaped, lamp

Description

Backlight Unit {BACKLIGHT UNIT}

1 is a partial perspective view before coupling of a direct backlight unit according to the related art

Figure 2 is a perspective view before coupling of the direct backlight unit according to an embodiment of the present invention

Explanation of symbols on the main parts of the drawings

20: cover bottom 21: cold cathode tube lamp

22: supporter side 24: home

25: upper structure 26: lamp support

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a backlight unit, and more particularly, to a backlight unit suitable for preventing partial darkening by changing a fastening structure of a cold cathode tube lamp having a U shape.

CRT (Cathode Ray Tube), one of the commonly used display devices, is mainly used for monitors such as TVs, measuring devices, and information terminal devices.However, due to the weight and size of the CRT itself, Could not respond actively to demands.

Therefore, in the trend of miniaturization and weight reduction of various electronic products, CRT has a certain limit in weight and size, and is expected to replace the liquid crystal display device (LCD) using the electro-optic effect, and gas discharge. There are plasma display panels (PDPs) and electroluminescent displays (ELDs) using electroluminescent effects, among which researches on liquid crystal displays (LCDs) are being actively conducted.

In order to replace the CRT, liquid crystal display devices having advantages such as small size, light weight, and low power consumption have been actively developed. In recent years, an ultra-thin flat display display having a thickness of only a few centimeters (Cm) is used. Developed enough to fulfill its role as a device, it is used in spacecraft, aircraft, laptop computers, laptop computer monitors, desktop computer monitors, and large information display devices. The demand for liquid crystal display devices continues to increase. to be.

Since most of the liquid crystal display devices are light-receiving devices that display images by controlling the amount of light coming from the outside, a separate light source, that is, a backlight unit, for irradiating light to the LCD panel is necessary.

In general, a backlight unit used as a light source of a liquid crystal display device is classified into an edge method and a direct method according to a method of arranging a cylindrical light emitting lamp.

First, the edge method is that the lamp unit is installed on the side of the light guide plate for guiding the light, the lamp unit is a lamp that emits light, the lamp holder which is inserted at both ends of the lamp to protect the lamp and the outer peripheral surface of the lamp and one side It is provided with a lamp reflector plate fitted to the side of the light guide plate to reflect the light emitted from the lamp toward the light guide plate.

The edge method in which the lamp unit is installed on the side of the light guide plate is applied to a relatively small liquid crystal display device such as a monitor of a laptop computer and a desktop computer, and has good light uniformity and a long durability life. It is advantageous to thin the liquid crystal display device.

On the other hand, the direct method began to be developed mainly as the size of the liquid crystal display device became larger than 20 inches, and arranged a plurality of lamps in a row on the lower surface of the diffuser plate to direct light directly to the front of the LCD panel. will be.

The direct method is mainly used for a large screen liquid crystal display device requiring high luminance because the light utilization efficiency is higher than that of the edge method.

However, the liquid crystal display device adopting the direct method is used as a large monitor or a television, so it takes longer to use than a laptop computer and the number of lamps is larger, so that the liquid crystal of the direct method is lower than the edge type liquid crystal display device. It is more likely that a lamp that will not turn on will appear due to the failure and life of the lamp in the display.

In addition, in the edge method in which the lamp units are installed on both side surfaces of the light guide plate, due to the life and failure of the lamp, for example, when only one lamp is not turned on, only the brightness on the screen is lowered. However, in the direct method, since a plurality of lamps are installed at the bottom of the screen, for example, due to the life and failure of the lamp, if one lamp does not light up, the part where the lamp is not lit becomes significantly darker than the other part. The part that does not appear immediately on the screen.

For this reason, since the lamp is frequently replaced in the direct type liquid crystal display device, the direct type liquid crystal display device should have an easy structure for disassembling and assembling the lamp unit.

Hereinafter, a conventional backlight unit will be described with reference to the accompanying drawings.

1 is a partial perspective view before coupling of a direct backlight unit according to the related art.

In the conventional backlight unit, as shown in FIG. 1, a plurality of cold cathode tube lamps (CCFLs) 11 formed in a 'U' shape on the cover bottom 10 are arranged at regular intervals, and the cold cathode tube lamps ( 11 is provided on both sides of the supporter side 12 for fixing it, and a plurality of lamp holders 13 for fixing the U-shaped portion of the cold cathode tube lamp 11 is provided. At this time, the lamp holder 13 is formed with a hole 14 suitable for the U-shaped width of the cold cathode tube lamp 11. That is, one cold cathode tube lamp 11 is fixed to the hole 14 of one lamp holder 13.

The upper structure 15 is provided along an edge portion of the cover bottom 10.

A plurality of supports 16 for supporting the lamps are provided in the light emitting surface on which the cold cathode tube lamps 11 are arranged.

Although not shown in the drawing, first and second electrodes are disposed in both ends of the cold cathode tube lamp 11, respectively, and the first and second power sources for applying power to the first and second electrodes. Lines are connected to each other, and a fluorescent layer is coated on an inner surface of the cold cathode tube lamp 11, and an argon gas and a mercury gas are filled in the lamp.

In addition, a reflector is further provided on the upper surface of the cover bottom 10 in order to increase the light transmission efficiency to the liquid crystal panel.

However, the backlight unit according to the prior art has the following problems.

Although the lamp holder 13 guides the U-shaped portion (bending portion) of the 'U' shaped lamp, the cold cathode lamp 11 can be protected during the impact test, but the lamp holder holding the U-shaped portion ( 13) heat loss occurs.

As a result, the portion fixed by the lamp holder 13 of the cold cathode tube lamp 11, that is, the U-shaped portion has a lower temperature than the other portion, and the mercury therein is attracted to the U-shaped portion of the lamp. This is due to the merging of mercury in the cold direction.

As such, when mercury is concentrated in a U-shaped portion having a low temperature, partial darkening may occur in a portion of relatively low mercury, for example, the first and second electrode portions.

Therefore, the light emission reliability of the backlight unit is lowered.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a backlight unit suitable for improving the light emitting reliability by preventing the occurrence of partial dark phenomenon.

The backlight unit according to the present invention for achieving the above object comprises a plurality of lamps formed in a 'U' shape on the cover bottom; A supporter side for guiding it on both sides of the lamp; And a plurality of grooves provided to fix the lamp in the supporter side on one side adjacent to the 'U' shaped portion of the lamp.

Cold Cathode Fluorescent lamps each having first and second electrodes disposed at both ends of the lamp and having first and second power lines connected to the first and second electrodes for supplying power. Lamp: CCFL).

The groove is characterized in that it is formed to match the width of the U-shape of the lamp.

The groove formed in the supporter side is configured to have a gap after the lamp is fixed so that heat can circulate in the U-shaped portion (bending portion) of the lamp.

Both ends where the first and second electrodes of the lamp are formed are fitted into and fixed to the holes of the side supporters on the other side.

And an upper structure along the edge edge of the cover bottom, and a plurality of supports for supporting the lamp in a light emitting surface on which the lamp is arranged.

Hereinafter, a backlight unit according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

Figure 2 is a perspective view before coupling of the direct backlight unit according to an embodiment of the present invention.

In the backlight unit according to the exemplary embodiment of the present invention, as shown in FIG. 2, a plurality of cold cathode tube lamps (CCFLs) 21 formed in a 'U' shape on the cover bottom 20 are arranged at regular intervals. On both sides of the cold cathode tube lamp 21, supporter sides 22 for guiding it are arranged.

 A groove 24 corresponding to the U-shaped width of the cold cathode tube lamp 21 is formed in the supporter side 22 of the portion adjacent to the U-shaped portion (bending portion) of the cold cathode tube lamp 21. That is, the groove | channel 24 for fixing the cold cathode tube lamp 21 directly to the supporter side 22 is comprised.

The groove 24 formed in the supporter side 22 has a gap after the cold cathode tube lamp 21 is fixed to allow the heat to circulate in the U-shaped portion (bending portion) of the cold cathode tube lamp 21. It is configured to have a margin). For example, it is formed to have a gap of approximately 2 mm at the end of the U-shaped portion and approximately 0.2 mm at the side portion thereof so that heat can be circulated.

In addition, an upper structure 25 is provided along the edge of the cover bottom 20 to fasten the results.

A plurality of lamp holders 26 are provided for supporting the lamps in the light emitting surface on which the cold cathode tube lamps 21 are arranged.

Although not shown in the drawings, first and second electrodes are disposed in both ends of the cold cathode tube lamp 21, respectively, and the first and second power lines for applying power to the first and second electrodes. These are connected, respectively, and a fluorescent layer is coated on the inner surface of the cold cathode tube lamp 21, and argon gas and mercury gas are filled in the lamp.

Further, light scattering means (not shown) is further configured between the cold cathode tube lamps 21 and the liquid crystal panel (not shown).

The light scattering means is to prevent the shape of the light emitting lamp from appearing on the display surface of the liquid crystal panel and to provide a light source having an overall uniform brightness distribution. A sheet (Diffusion sheet) and a diffusion plate (Diffusion plate) and the like are disposed.

In addition, a reflector (not shown) is further disposed on the inner surface of the cover bottom so that light generated from the cold cathode tube lamp 21 can be concentrated to the display unit of the liquid crystal panel. This is to maximize light utilization efficiency.

Both ends of the cold cathode tube lamp 21, on which the first and second electrodes are formed, are fitted into the holes of the side supporters 22 on the other side and are configured to be fixed.

As described above, the backlight unit of the present invention forms a groove 24 capable of directly holding (fixing) the cold cathode tube lamp 21 in the side supporter 22, so that the side supporter 22 serves as a lamp guide. It also protects the lamp during impact testing.

The backlight unit configured as described above emits light when power is applied to the first and second electrodes through the first and second power lines in the tube of the cold cathode tube lamp 21.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the above embodiments, but should be defined by the claims.

The backlight unit according to the present invention as described above has the following effects.

First, since the U-shaped portion (bending portion) of the cold cathode tube lamp can be fixed by having a groove on the supporter side, a separate lamp holder is not required as in the prior art. Therefore, it is possible to prevent the problem that the partial dark phenomenon occurs by taking heat away from the lamp holder, thereby improving light emission reliability.

Second, since the cold cathode tube lamp is fixed directly to the groove provided on the supporter side, the fastening structure can be simplified.

Claims (6)

A plurality of lamps formed in a 'U' shape on the cover bottom; A supporter side for guiding it on both sides of the lamp; And a plurality of grooves provided to fix the lamp in the supporter side on one side adjacent to the 'U'-shaped portion of the lamp. The method of claim 1, Cold Cathode Fluorescent lamps each having first and second electrodes disposed at both ends of the lamp and having first and second power lines connected to the first and second electrodes for supplying power. Lamp: Backlight unit, characterized in that consisting of (CCFL). The method of claim 1, The groove is formed in accordance with the U-shaped width of the lamp unit. The method of claim 1, The groove formed in the supporter side is configured to have a gap after the lamp is fixed to allow heat to circulate in the U-shaped portion (bending portion) of the lamp. The method of claim 2, Both ends of the first and second electrodes of the lamp is formed is fixed to the hole of the side supporter on the other side is fixed. The method of claim 1, An upper structure along an edge portion of the cover bottom; And a plurality of supports for supporting the lamps in a light emitting surface on which the lamps are arranged.

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