KR20050019194A - Back light assembly and liquid crystal display having the same - Google Patents

Abstract

PURPOSE: A back light assembly and an LCD(Liquid Crystal Display) having the back light assembly are provided to make the lengths of the first and second lamp electrode lines, which apply a lamp driving voltage generated by an inverter to both ends of an external electrode lamp, identical to each other to improve luminance uniformity. CONSTITUTION: A back light assembly includes a plurality of lamps(200) generating light, the first and second power supply members(310,320) connected to both ends of each of the lamps, an inverter for generating a lamp driving voltage, and the first and second lamp electrode lines(240,250) for respectively connecting the inverter to the first and second power supply members. Each of the lamps includes a lamp tube, the first external electrode formed at one end of the lamp tube, and the second external electrode formed at the other end of the lamp tube.

Description

BACK LIGHT ASSEMBLY AND LIQUID CRYSTAL DISPLAY HAVING THE SAME}

The present invention relates to a backlight assembly and a liquid crystal display having the same, and more particularly, to a backlight assembly and a liquid crystal display having the same in a direct type structure using an external electrode lamp.

In general, a liquid crystal display (LCD) is one of flat display devices for displaying an image using a liquid crystal (LC).

Such a liquid crystal display device has an advantage of smaller volume and weight than other display devices. In addition, the liquid crystal display device has a display quality comparable to or superior to that of other display devices, and thus the liquid crystal display device is widely used as a display device of most information processing devices.

Since the liquid crystal used in the liquid crystal display device is a light receiving element that does not generate light by itself, the liquid crystal display device requires a separate light to perform the display. As a result, a normal liquid crystal display device is provided with a backlight assembly that provides light for display.

Recently, as the size of the liquid crystal display device increases, the size of the liquid crystal display panel and the backlight assembly for displaying an image also increases. As a result, the liquid crystal display device has widely adopted a direct type backlight assembly having a plurality of lamps arranged side by side at the rear of the liquid crystal display panel to provide light directly to the liquid crystal display panel.

Since the direct backlight assembly requires a large number of lamps for high brightness and uniformity of brightness, an external electrode lamp capable of parallel driving capable of driving a plurality of lamps with a single inverter has been recently developed.

On the other hand, the inverter for generating a lamp driving voltage for driving the external electrode lamp is disposed to the left or right side from the back of the backlight assembly. In addition, the lamp driving voltage generated by the inverter is separated into a first driving voltage and a second driving voltage, respectively, to the first and second external electrodes formed at both ends of the external electrode lamp through the first lamp electrode line and the second lamp electrode line. Is approved.

However, the lengths of the first and second lamp electrode lines are different from each other because the inverters are disposed to the left or the right side, and such a difference in length causes a difference in the leakage current of the first and second lamp electrode lines. Accordingly, a difference occurs between the first driving voltage and the second driving voltage applied to both ends of the external electrode lamp due to the difference in leakage current between the first and second lamp electrode lines. The difference has a problem of impairing the uniformity of luminance.

Accordingly, the present invention has been made in view of such a problem, and an object of the present invention is to equalize the lengths of the first and second lamp electrode lines for applying the lamp driving voltage generated in the inverter to both ends of the external electrode lamp. It is to provide a backlight assembly that can improve the brightness uniformity.

Another object of the present invention is to provide a liquid crystal display device having the above-described backlight assembly.

The backlight assembly for achieving the above object of the present invention includes a plurality of lamps for generating light, first and second power supply members connected to both ends of the lamp, an inverter for generating a lamp driving voltage, and the inverter and And a first lamp electrode line and a second lamp electrode line connecting the first and second power supply members, respectively.

The plurality of lamps are external electrode lamps having a lamp tube, a first external electrode formed outside one end of the lamp tube, and a second external electrode formed outside the other end of the lamp tube.

The first power supply member fixes the first external electrode and applies a first driving voltage to the first external electrode. The second power supply member fixes the second external electrode and applies a second driving voltage to the second external electrode.

The inverter generates the first driving voltage and the second driving voltage for driving the external electrode lamp, and applies them to both ends of the external electrode lamp.

The first lamp electrode line is connected to the first power supply member to supply the first driving voltage generated from the inverter to the first external electrode. The second lamp electrode line is connected to the second power supply member to supply the second driving voltage generated from the inverter to the second external electrode. In this case, the first lamp electrode line and the second lamp electrode line have the same length.

According to another aspect of the present invention, a liquid crystal display device includes a backlight assembly for supplying light, a display unit for displaying an image using light supplied from the backlight assembly, and the display unit to the backlight assembly. It includes a top chassis for fixing.

The backlight assembly may be connected to a plurality of lamps for generating light, an inverter for generating a first driving voltage and a second driving voltage for driving the lamp, and one end of the lamp for applying the first driving voltage. A first lamp electrode line and a second lamp electrode line connected to the other end of the lamp for applying the second driving voltage.

At this time, the length of the first lamp electrode line and the second lamp electrode line is the same.

According to the backlight assembly and the liquid crystal display device having the same, the lengths of the first lamp electrode line and the second lamp electrode line are formed to be the same, thereby eliminating the difference between the first driving voltage and the second driving voltage and improving the uniformity of luminance. You can.

Hereinafter, with reference to the accompanying drawings, it will be described in detail a preferred embodiment of the present invention.

1 is an exploded perspective view illustrating a liquid crystal display according to an exemplary embodiment of the present invention.

Referring to FIG. 1, the liquid crystal display 1000 according to an exemplary embodiment of the present invention may include a display unit 100 for displaying an image, a backlight assembly 800 for providing light to the display unit 100, and the display unit 100. A top chassis 900 for fixing the display unit 100 to the backlight assembly 800 is included.

The display unit 100 includes a liquid crystal display panel 110 displaying an image, a data printed circuit board 120 and a gate printed circuit board 130 for driving the liquid crystal display panel 110. The data printed circuit board 120 and the gate printed circuit board 130 are electrically connected to the liquid crystal display panel 110 by a data tape carrier package (TCP) 140 and a gate TCP 150, respectively. Connected.

The liquid crystal display panel 110 includes a thin film transistor (hereinafter, referred to as TFT) substrate 114, a color filter substrate 112 facing the TFT substrate 114, and a liquid crystal layer interposed between the two substrates. Not shown). The TFT substrate 114 is a transparent glass substrate in which a switching element TFT (not shown) is formed in a matrix form. Data and gate lines are respectively connected to the source and gate terminals of the TFTs, and a pixel electrode made of a transparent conductive material is connected to the drain terminal.

The color filter substrate 112 is provided to face the TFT substrate 114. The color filter substrate 112 is a substrate in which RGB pixels as color pixels are formed by a thin film process. The common electrode made of a transparent conductive material is coated on the front surface of the color filter substrate 112.

The display unit 100 having such a configuration expresses the gray scale by adjusting the transmittance of the light provided from the backlight assembly 800 by switching the TFT, and using the RGB pixels of the color filter substrate 112 to display color. Implement

The backlight assembly 800 includes a plurality of lamps 200 for generating light, a first power supply member 310 and a second power supply member 320 connected to both ends of the lamp 200, respectively. .

Each of the plurality of lamps 200 is formed on a rod-shaped lamp tube 210 and a first external electrode 220 formed outside one end of the lamp tube 210 and outside the other end of the lamp tube 210. An external electrode lamp (EEFL) having a second external electrode 230 is provided. Discharge gas (not shown) is injected into the lamp tube 210, and the first and second external electrodes 220 and 230 are made of a conductive material to surround the outside of both ends of the lamp tube 210. Is formed.

The first power supply member 310 is disposed at one end side of the lamp 200 and is coupled to the first external electrode 220 to fix one end of the lamp 200. The second power supply member 320 is disposed at the other end side of the lamp 200 and is coupled to the second external electrode 230 to fix the other end of the lamp 200. In this case, the first and second power supply members 310 and 320 fix the plurality of lamps 200, and at the same time, the first and second external electrodes are made of a conductive material to supply the lamp driving voltage supplied from the outside. It serves to apply to (220, 230).

The backlight assembly 800 according to an embodiment of the present invention includes a container 500 for accommodating the first power supply member 310 and the second power supply member 320 to which the plurality of lamps 200 are fixed. And an inverter 600 disposed on the rear surface of the storage container 500 to generate first and second driving voltages for driving the lamp 200.

The inverter 600 is disposed to the right or left side of the rear surface of the storage container 500. This is because a control printed circuit board (not shown) for controlling the display unit 100 or an optical sensor unit (not shown) for measuring a leakage current of the lamp 200 is located at the center of the storage container 500. Because they are placed, they are subject to positional constraints.

The first and second driving voltages generated by the inverter 600 have the same voltage level but opposite voltage values. The first and second driving voltages are applied to the first and second external electrodes 220 and 230, respectively. Therefore, each lamp 200 has twice the voltage level of the first and second driving voltages. A large voltage value is applied.

Meanwhile, the backlight assembly 800 includes first and second fixing members 410 and 420 to which the first and second power supply members 310 and 320 are fixed, respectively, the plurality of lamps 200 and the Arranged between the display unit 100 and the optical member (710, 720) for improving the brightness uniformity and brightness of the light emitted from the lamp 200, and is mounted on the bottom surface of the storage container 500 is the lamp 200 It further includes a reflecting plate 730 for reflecting the light generated in the direction of the optical members (710, 720).

The first and second fixing members 410 and 420 fix the first and second power supply members 310 and 320, and electrically insulate the storage container 500.

The optical members 710 and 720 are mounted on a diffusion plate 710 for diffusing the light emitted from the lamp 200 and a plurality of optical sheets for improving the brightness of light by being mounted on the diffusion plate 710. It consists of 720.

In addition, the backlight assembly 800 fixes the optical members 710 and 720, the third fixing member 740 for guiding the mounting position of the display unit 100, and the length of the lamp 200. It may further include first and second support members 750a and 750b parallel to the direction and mounted on the inner wall of the storage container 500 so as to face each other to support the diffusion plate 710.

The backlight assembly 800 having such a configuration will be described in more detail with reference to the accompanying drawings.

FIG. 2 is a perspective view specifically illustrating a coupling relationship between the lamp illustrated in FIG. 1 and the first and second power supply members.

Referring to FIG. 2, the first power supply member 310 is disposed at one end side of the lamp 200 to connect the first external electrode 220 to each other, and the first fixing plate 312. The first clip part 314 protrudes from the fixing plate 312 to fix each of the first external electrodes 220. In addition, the second power supply member 320 is disposed on the other end side of the lamp 200 to connect the second external electrode 230 to each other, and the second fixing plate 322, the second fixing plate 322 And a second clip part 324 that protrudes from the second external electrode 230 to fix each of the second external electrodes 230.

Meanwhile, the backlight assembly 800 according to an embodiment of the present invention may include a first lamp electrode line 240 for applying the first driving voltage generated from the inverter 600 to the first external electrode 220. And a second lamp electrode line 250 for applying the second driving voltage to the second external electrode 230.

One end of the first lamp electrode line 240 is coupled to the first coupling hole 316 formed in the first fixing plate 312 by a screw fastening method, and the other end is drawn out to the rear surface of the storage container 500. It is connected to the inverter 600. In addition, one end of the second lamp electrode wire 250 is coupled to the second coupling hole 326 formed in the second fixing plate 322 by a screw fastening method, and the other end of the second lamp electrode wire 250 is a rear surface of the storage container 500. It is withdrawn and connected to the inverter 600.

In this case, the first lamp electrode line 240 and the second lamp electrode line 250 have the same length.

3 is a view illustrating mounting positions of the first and second lamp electrode lines illustrated in FIG. 2, and FIG. 4 is a perspective view illustrating in detail a mounting position of the first lamp electrode lines illustrated in FIG. 3.

3 and 4, one end of the first lamp electrode wire 240 is screwed into the first coupling hole 316 of the first fixing plate 312, and then an upper inner wall of the storage container 500. It is stored by a certain length along. Subsequently, the drawing is again drawn out toward the first fixing member 410 along the upper inner wall of the storage container 500, and then received through the first through hole 412 formed at one side of the first fixing member 410. It is withdrawn to the back of the container 500. In this case, the first lamp electrode line 240 is preferably mounted in the first support member 750a, and may be fixed by a tape or the like.

One end of the second lamp electrode wire 250 is screwed into the second coupling hole 326 of the second fixing plate 322, and then the first fixing member 410 is formed along the lower inner wall of the storage container 500. ) Is drawn to the side. Thereafter, the second through hole (not shown) formed at the other side of the first fixing member 410 is drawn out to the rear surface of the storage container 500. In this case, the second lamp electrode line 250 may be drawn out to the first fixing member 410 through the inside of the second supporting member 750b, and may be fixed by a tape or the like.

FIG. 5 is a rear view illustrating the storage container shown in FIG. 3 upside down.

Referring to FIG. 5, the inverter 600 generating the first driving voltage and the second driving voltage for driving the lamp 200 are disposed on one side of the rear surface of the storage container 500.

The first and second lamp electrode lines 240 and 250 are drawn out from the inside of the storage container 500 in a direction in which the inverter 600 is biased. In this case, the first and second lamp electrode wires 240 and 250 may be separated and drawn out through the other side of the storage container 500.

As such, the first and second lamp electrode wires 240 and 250 drawn to the rear surface of the storage container 500 are connected to the inverter 600, respectively.

On the other hand, in the present embodiment, the first lamp electrode wire 240 has a structure in which a part is mounted in the interior of the storage container 500 in consideration of protection from external impact and appearance quality, but the length of the first lamp electrode wire 240 If the length of the second lamp electrode line 250 and the same, the first lamp electrode line 240 may be mounted at any position.

According to the backlight assembly and the liquid crystal display having the same, the luminance uniformity is improved by making the lengths of the first and second lamp electrode lines equal to apply the lamp driving voltage generated from the inverter to both ends of the external electrode lamp. You can.

In the detailed description of the present invention described above with reference to a preferred embodiment of the present invention, those skilled in the art or those skilled in the art having ordinary knowledge in the scope of the invention described in the claims to be described later It will be understood that various modifications and variations can be made in the present invention without departing from the scope of the present invention.

1 is an exploded perspective view illustrating a liquid crystal display according to an exemplary embodiment of the present invention.

FIG. 2 is a perspective view specifically illustrating a coupling relationship between the lamp illustrated in FIG. 1 and the first and second power supply members.

3 is a diagram illustrating a mounting position of the first and second lamp electrode lines illustrated in FIG. 2.

4 is a perspective view illustrating in detail a mounting position of the first lamp electrode line illustrated in FIG. 3.

FIG. 5 is a rear view illustrating the storage container shown in FIG. 3 upside down.

<Explanation of symbols for the main parts of the drawings>

100: display unit 110: liquid crystal display panel

200: lamp 210: lamp tube

220: first external electrode 230: second external electrode

240: first lamp electrode line 250: second lamp electrode line

310: first power supply member 320: second power supply member

312: first fixing plate 314: first clip portion

410: first fixing member 420: second fixing member

500: storage container 600: inverter

710: diffuser 720: optical sheet

800: backlight assembly 900: top chassis

Claims (10)

A plurality of lamps having a lamp tube, a first external electrode formed outside one end of the lamp tube, and a second external electrode formed outside the other end of the lamp tube; A first power supply member which fixes the first external electrode and applies a first driving voltage to the first external electrode; A second power supply member which fixes the second external electrode and applies a second driving voltage to the second external electrode; An inverter generating the first driving voltage and the second driving voltage for driving the lamp; A first lamp electrode line connected to the first power supply member to supply the first driving voltage generated from the inverter to the first external electrode; And And a second lamp electrode line connected to the second power supply member to supply the second driving voltage generated from the inverter to the second external electrode and having the same length as the first lamp electrode line. The method of claim 1, The first power supply member includes a first fixing plate disposed at one end side of the lamp, and a first clip portion protruding from the first fixing plate to fix each of the first external electrodes. And the second power supply member comprises a second fixing plate disposed at the other end side of the lamp, and a second clip portion protruding from the second fixing plate to fix each of the second external electrodes. The method of claim 2, The first lamp electrode line is connected to the first fixing plate, And the second lamp electrode line is connected to the second fixing plate. The backlight assembly of claim 1, wherein the first driving voltage and the second driving voltage have the same voltage value, and the phases are opposite to each other. The method of claim 1, A first fixing member to which the first power supply member is fixed; A second fixing member to which the second power supply member is fixed; And And a storage container accommodating the first fixing member and the second fixing member. The backlight assembly of claim 5, wherein the inverter is disposed to the right or left side of the rear surface of the storage container. The backlight assembly of claim 6, wherein the second lamp electrode line is led from the second power supply member to the first power supply member along the inner wall of the storage container and connected to the inverter. The method of claim 7, wherein Further comprising a first support member and a second support member mounted on the inner wall of the container facing each other in a direction parallel to the lamp, The first lamp electrode line is partially accommodated in the first support member, The second lamp electrode line is led out to the first power supply member side through the inside of the second support member. A plurality of lamps for generating light, a first power supply member for connecting one end of the lamp, a second power supply member for connecting the other end of the lamp, a first driving voltage and a second drive for driving the lamp An inverter for generating a voltage, a first lamp electrode line connected with the first power supply member to supply the first driving voltage generated in the inverter to one end of the lamp, and the second driving generated in the inverter A backlight assembly connected to the second power supply member for supplying a voltage to the other end of the lamp, the backlight assembly including a second lamp electrode line having the same length as the first lamp electrode line; A display unit displaying an image using light emitted from the backlight assembly; And And a top chassis for fixing the display unit to the backlight assembly. The method of claim 9, The lamp is an external electrode lamp having a first external electrode formed outside one end and a second external electrode formed outside the other end, And the first driving voltage and the second driving voltage have the same voltage value, and are out of phase.