KR20040007772A - Direct light type backlight assembly of liquid crystal display - Google Patents

Abstract

PURPOSE: A back light assembly for a direct type liquid crystal display is provided to stably fix a plurality of lamps and maintain regular gaps of the lamps, and prevent a diffusion plate from drooping, thereby improving reliability of a liquid crystal panel and realizing a display of high quality. CONSTITUTION: A diffusion plate is provided to diffuse light emitted from a plurality of lamps. A container contains the plurality of lamps at a bottom surface and contains the diffusion plate on an upper surface. A diffusion plate droop preventing plate(350) includes a plurality of lamp guide grooves(355) guiding the plurality of lamps respectively, and an upper surface supporting a lower surface of the diffusion plate for preventing droop of the diffusion plate.

Description

DIRECT LIGHT TYPE BACKLIGHT ASSEMBLY OF LIQUID CRYSTAL DISPLAY}

The present invention relates to a backlight assembly for a direct type liquid crystal display device having a diffusion plate deflection prevention function.

As a display device, a liquid crystal display device having a function such as light weight, small size, full color, high resolution, and the like is widely used. The liquid crystal display requires light because an image is displayed using a liquid crystal, which is a light receiving element that does not emit light by itself. Therefore, the liquid crystal display receives light from the backlight assembly attached to the rear surface of the liquid crystal display panel and displays an image.

The backlight assembly is divided into a direct type and an edge type according to the position of the light source. The edge type backlight assembly has a structure in which a lamp unit is installed on the side of the light guide plate, and is mainly applied to a relatively small liquid crystal display device such as a laptop and a desktop computer. Such an edge type backlight assembly has a good light uniformity, a long service life, and is advantageous for thinning a liquid crystal display device.

On the other hand, the direct type backlight assembly is a structure mainly developed as the size of the liquid crystal display device increases in size, and one or more lamps are arranged in a row on the lower surface of the diffusion plate to irradiate light on the entire liquid crystal display panel. Such a direct type backlight assembly has advantages in that a plurality of light sources can be used in comparison with an edge type backlight assembly, thereby ensuring a high luminance, but a luminance becomes uneven when thinned.

1 is an exploded perspective view schematically illustrating a structure of a backlight assembly 100 of a conventional direct type liquid crystal display, and FIG. 2 is a cross-sectional view taken along line AA ′ of FIG. 1.

1 and 2, the backlight assembly 100 of the conventional direct type liquid crystal display device includes an optical sheet 110, a diffusion plate 120, an accommodation member 130, a lamp 140, and a lamp ring 142. ), The diffusion plate sag prevention member 150 is provided.

The diffusion plate 120 is accommodated on the upper surface of the housing member 130, and diffuses the light generated from the plurality of lamps 140 to make the luminance distribution of the light even more uniform. The optical sheet 110 adjusts the luminance characteristic of the light emitted from the diffuser plate 120.

The plurality of lamps 140 are arranged in parallel at regular intervals to generate light. A lamp ring 142 may be installed at a portion of the lamp 140, and the lamp ring 142 may have a ring shape fitted to the circumferential surface of the lamp 140. The lamp ring 142 prevents the flow of the lamp 140 with respect to the bottom surface of the accommodating member 130 so as to prevent the lamp 140 from being damaged during vibration or shock due to the characteristics of the long and thin lamp 140. It is to. The lamp ring 142 is manually bonded and fixed to the circumferential surface of the lamp 140 by using an adhesive or the like.

The storage member 130 carries the plurality of lamps 140 on the bottom surface and accommodates the diffusion plate 120 on the top surface. The diffusion plate sag preventing member 150 is installed on the bottom surface of the housing member 130 and has a truncated conical shape that decreases in diameter as it proceeds toward the diffuser plate 120. As shown in FIG. A portion of the plate 120 is supported to prevent sagging of the diffusion plate 120. The cone-shaped diffuser plate sag-preventing member 150 as described above is manually bonded and fixed by using adhesives at various places on the bottom surface of the housing member 130.

Although not shown in the drawings, a reflective sheet may be disposed between the bottom surface of the accommodation member 130 and the lamp 140. The reflective sheet may maximize the light utilization efficiency of the lamp 140 by allowing the light toward the bottom of the housing member 130 to be reflected at the bottom of the light generated by the lamp 140.

In the backlight assembly 100 of the conventional direct type liquid crystal display, the lamps 140 are arranged in parallel at regular intervals to maintain uniformity of luminance, and the diffusion plate sag preventing member may be disposed to prevent sagging of the diffusion plate 120. 150). However, simply by placing the lamp 140 in parallel at regular intervals and using the lamp ring 142, as in the prior art, it is difficult to maintain the uniformity of the luminance because it is not resistant to external impact or shaking.

In addition, only using the diffusion plate deflection preventing member 150 having a conventional truncated cone shape could not fundamentally prevent the diffusion plate deflection in the backlight assembly 100 of the direct type liquid crystal display having the large screen. . As a result, there is a problem that the reliability of the liquid crystal display device is lowered and a high quality display cannot be realized.

Furthermore, the conventional lamp ring 142 and the cone-shaped diffuser plate sag-preventing member 150 have to go through a process of being fixed by the assembler using an adhesive or the like, and thus, the assembly process is cumbersome and requires a lot of time. . Sometimes there was a problem that some of the lamp ring 142 and the truncated cone-shaped diffuser plate sag preventing member 150 may fall off.

Therefore, the technical and problem of the present invention are to solve such a conventional problem, and an object of the present invention is to prevent the flow of the lamp and to ensure that the lamp is assembled at regular intervals to maintain a uniform brightness uniform and to prevent sagging of the diffusion plate It is to provide a backlight assembly of a direct type liquid crystal display device having a diffusion plate deflection prevention member that performs a composite function.

1 is an exploded perspective view schematically illustrating a structure of a backlight assembly of a conventional direct type liquid crystal display.

FIG. 2 is a cross-sectional view taken along line AA ′ of FIG. 1.

3 is an exploded perspective view schematically illustrating a structure of a backlight assembly of a direct type liquid crystal display according to an exemplary embodiment of the present invention.

4 is a cross-sectional view taken along line BB ′ of FIG. 3.

FIG. 5A is a perspective view illustrating a preferred embodiment of a diffusion plate deflection preventing member used in the backlight assembly of the direct type liquid crystal display of FIG. 3.

FIG. 5B is a perspective view illustrating another preferred embodiment of the diffusion plate deflection preventing member used in the backlight assembly of the direct type liquid crystal display of FIG. 3.

6 is an enlarged view illustrating a portion C of the diffusion plate deflection prevention member of FIG. 4.

7 is a cross-sectional view showing a structure in which the lower surface of the diffusion plate deflection prevention member according to an embodiment of the present invention is fastened using the receiving member and the locking protrusion.

FIG. 8 is a plan view of the backlight assembly of the direct type liquid crystal display of FIG. 3.

FIG. 9 is an enlarged view of portion D of FIG. 8.

10 is an exploded perspective view schematically illustrating a structure of a backlight assembly of a direct type liquid crystal display according to another exemplary embodiment of the present invention.

FIG. 11 is a cross-sectional view taken along line EE ′ of FIG. 10.

FIG. 12 is a perspective view illustrating a preferred embodiment of a diffusion plate deflection preventing member used in the backlight assembly of the direct type liquid crystal display of FIG. 10.

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

100, 300, 800: backlight assembly 110, 310: optical sheet

120, 320: diffusion plate 130, 330: storage container

330a: bottom chassis 330b: storage frame

140, 340: lamp 142: lamp ring

150, 350, 1050: Diffusion plate deflection prevention member

355: Lamp Guide Groove

357a, 357b: first and second locking projections 357c: insertion projection

In order to achieve the above object, a backlight assembly of a direct type liquid crystal display according to the present invention includes a diffusion member for diffusing light generated from a lamp, and the plurality of lamps arranged in parallel on a bottom surface of the diffusion member. And an accommodating member for accommodating the upper surface, and a plurality of lamp guide grooves for guiding each of the lamps accommodated in the bottom surface, and the upper surface supporting the lower surface of the diffusing member to sag the diffusing member. And a diffusion plate drooping prevention member for preventing.

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

3 is an exploded perspective view schematically illustrating a structure of a backlight assembly of a direct type liquid crystal display according to an exemplary embodiment of the present invention, and FIG. 4 is a cross-sectional view taken along line BB ′ of FIG. 3.

3 and 4, the backlight assembly 300 of the direct type liquid crystal display according to the exemplary embodiment of the present invention may include an optical sheet 310, a diffusion plate 320, an accommodation member 330, and a lamp ( 340, lamp ring 342, and diffusion plate sag prevention member 350.

The plurality of lamps 340 are arranged in parallel at regular intervals to generate light, and a lamp ring 342 may be installed at a portion of the lamp 340.

The diffusion plate 320 is disposed on the upper surface of the housing member 330, and the optical sheet 310 is disposed on the upper surface of the diffusion plate 320 to adjust the luminance characteristics of the light emitted from the diffusion plate 320.

The storage member 330 may include a bottom chassis 330a and a storage frame 330b. (See FIG. 4) The storage member 330 may include a plurality of lamps 140 on the bottom surface of the bottom chassis 330a. It accommodates, and accommodates the diffuser plate 120 in the upper surface. Here, the storage frame 330b may be manufactured by connecting three plates in a frame shape, and although not shown in the drawing, the plate is formed along the outer edge of the storage frame 330b in order to couple with the bottom chassis 330a. At least one catch hook may be formed.

The bottom chassis 330a may be formed of a bottom surface and sidewalls extending from an edge of the bottom surface. Although not shown in the drawings, a hook coupling hole coupled to the hooking hook of the storage frame 330b described above may be formed on the side wall.

A reflection sheet 334 for reflecting light generated from the lamp toward the diffuser plate 320 is provided between the bottom surface of the bottom chassis 330a and the lamp 340.

The diffusion plate deflection prevention member 350 of the present invention may have a rectangular plate shape having both sides inclined, and support the diffusion plate 320 to prevent the diffusion plate 120 from sagging. In addition, the diffusion plate sag preventing member 350 is a plurality of lamps 340 arranged in parallel at regular intervals using the lamp guide groove 355 formed to correspond to the arrangement position and the arrangement interval of the plurality of lamps 340. By guiding the plurality of lamps 340 to maintain a constant interval.

5A is a perspective view illustrating a preferred embodiment of the diffusion plate deflection preventing member 350 used in the backlight assembly 300 of the direct type liquid crystal display of FIG. 3, and FIG. It is the figure which expanded and showed a part.

5A and 6, in the diffusion plate deflection preventing member 350, a lamp guide groove 355 for guiding the lamp 340 is formed at a lower surface 351b, and a threaded portion of the reflective sheet 334 is formed. Guide grooves 353 having a shape corresponding to the guide portion of the threaded portion are formed. As shown in FIG. 6, a gap of about 0.5 mm to about 1 mm may be provided between the lamp guide groove 355 and the lamp 340 so as not to cause a molding problem.

In addition, the lower projections 357a and 357b for binding the lower surface 351b of the diffusion plate deflection prevention member 350 to the bottom surface of the bottom chassis 330a on the lower surface 351b of the diffusion plate deflection preventing member 350. ) Is formed. Each of the locking protrusions 357a and 357b is alternately formed on the lower surface of the diffusion plate deflection preventing member 350 so as to alternate the direction of protrusion as shown in FIG. 6. In addition, although not shown in the drawings, the engaging projections 357a and 357b may be integrally formed so that the projection directions are opposite to each other.

The diffusion plate sag preventing member 350 is preferably made of a transparent material such as acrylic, which can transmit light generated from the lamp 340. In addition, the hardness of the diffusion plate 320 may be made of silicon rubber (silicon rubber).

7 is a cross-sectional view illustrating a structure in which the lower surface 351b of the diffusion plate deflection preventing member 350 is fastened using the bottom chassis 330a and the locking protrusions 357a and 357b according to an exemplary embodiment of the present invention. .

Referring to FIG. 7, a locking protrusion receiving hole for receiving the locking protrusions 357a and 357b is formed in the bottom surface of the bottom chassis 330a and passes through the bottom surface of the bottom chassis 330a. The locking protrusions 357a and 357b formed on the lower surface 351b of the diffusion plate deflection preventing member 350 are inserted into the locking protrusion accommodation holes by giving a snap so that the protrusions of the locking protrusions 357a and 357b are caught. Passes through the storage hole. The lower surface 351b of the diffusion plate deflection prevention member 350 is fixed to the bottom chassis 330a through the snap fit structure as described above.

FIG. 5B is a perspective view illustrating another preferred embodiment of the diffusion plate deflection preventing member used in the backlight assembly of the direct type liquid crystal display of FIG. 3.

The insertion protrusion 357c formed on the lower surface 351b of the diffusion plate deflection prevention member 350 is inserted into the insertion protrusion insertion groove formed on the bottom surface of the bottom chassis 330a, and the diffusion plate deflection prevention member is formed by using a screw or the like. The lower surface 351b of the 350 may be fixed to the bottom surface of the bottom chassis 330a.

FIG. 8 is a plan view of the backlight assembly 300 of the direct type liquid crystal display of FIG. 3, and FIG. 9 is an enlarged view of portion D of FIG. 8.

8 and 9, both side surfaces 351c and 351d of the diffusion plate deflection preventing member 350 may be formed in the fixing grooves 332 (see FIG. 9) formed on two opposite sides of the receiving frame 330b. Is fitted and fixed. Although not shown in the drawings, the side surfaces 351c and 351d of the diffusion plate deflection preventing member 350 may be inserted into the fixing grooves 332 (see FIG. 9) and fixed using a screw.

FIG. 10 is an exploded perspective view schematically illustrating a structure of a backlight assembly 1000 of a direct type liquid crystal display according to another exemplary embodiment of the present invention. FIG. 11 is a cross-sectional view taken along line E-E 'of FIG. 10. FIG. 10 is a perspective view illustrating a preferred embodiment of the diffusion plate deflection preventing member 1050 used in the backlight assembly 1000 of the direct type liquid crystal display of FIG. 10.

10 to 12, a support member 1059 having a triangular plate shape is formed on an upper surface 1051a of the diffusion plate deflection prevention member 1050 according to another preferred embodiment of the present invention, and the diffusion plate A portion of the plate of the deflection preventing member 1050 is formed with a groove 1058 for accommodating the threaded portion of the reflective sheet 334 as shown in FIG. 12.

In addition, the lower surface 1051b of the diffusion plate deflection preventing member 1050 is formed with the locking projections 1057a and 1057b as described above, and although not shown in the drawing, the locking projections 1057a and 1057b have mutually different projection directions. Of course, it may be formed integrally to be reversed. Alternatively, an insertion protrusion may be formed on the lower surface 1051b of the diffusion plate deflection preventing member 1050 so that the lower surface 1051b of the diffusion plate deflection preventing member 1050 may be fixed to the bottom surface of the bottom chassis 330a. Of course. Both side surfaces 1051c and 1051d of the diffusion plate deflection preventing member 1050 are fitted into and fixed to fixing grooves 332 (see FIG. 9) formed on two opposite sides of the receiving frame 330b.

The diffusion plate sag preventing member 350 may be made of a transparent material or a silicone rubber having a high hardness.

The support member 1059 having a triangular plate shape contacts the lower surface of the diffusion plate 320 to support the diffusion plate 320. The support member 1059 having a triangular plate shape reduces the contact area between the diffusion plate 320 and the diffusion plate sag preventing member 1050 to prevent a dark portion from appearing on the surface of the panel of the liquid crystal display when the contact area becomes large. It is for. In addition, as a result of forming the support member 1059 having a triangular plate shape among the diffusion plate deflection prevention members 1050, the weight corresponding to the space 1101 is reduced to reduce the overall weight of the diffusion plate deflection prevention member 1050. Can be reduced.

As the groove 1058 accommodates the threaded portion of the reflective sheet 334 and simultaneously forms the groove 1058, the weight of the groove 1058 is reduced to correspond to the space 1103, thereby reducing the overall weight of the diffusion plate deflection preventing member 1050. It is to reduce.

As described above, the diffusion plate sag preventing members 350 and 1050 are simultaneously fixed to two bottom surfaces of the bottom chassis 330a and two opposite sides of the storage frame 330b, and the lamp guide grooves 355 and 1055. By guiding the lamp 340, the lamp 340 may be stably fixed up, down, left, and right, and sagging of the diffusion plate 320 may be prevented.

The diffusion plate deflection preventing member as described above is fixed to the bottom and side surfaces of the housing member when used in a backlight assembly of a direct type liquid crystal display device having a large screen. As well as stably fixed and a plurality of lamps can maintain a constant interval as well as ii) there is an effect of preventing the deflection of the diffusion plate by supporting the diffusion plate.

As a result, it has the effect of improving the reliability of a liquid crystal display panel and enabling high quality display.

In addition, when using a lamp ring to fix the conventional lamp or when using a cone-shaped diffuser plate deflection prevention member to improve the disadvantages that the assembly process is cumbersome and the assembly process is complicated to simplify the assembly process and improve the assembly efficiency. In addition, when some of the conventional lamp ring and the cone-shaped diffuser plate sag prevention member is separated, the display quality is also reduced. In addition, there is an effect that can reduce the production cost as compared to the case of using a conventional lamp ring and the truncated plate-shaped diffusion plate deflection prevention member.

Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and changed within the scope of the present invention without departing from the spirit and scope of the invention described in the claims below. I can understand that you can.

Claims (7)

A diffusion member for diffusing light generated from the lamp; An accommodating member accommodating the plurality of lamps arranged in parallel on a bottom surface and accommodating the diffusion member on an upper surface; And A diffusion plate deflection prevention member having a plurality of lamp guide grooves for guiding each of the plurality of lamps stored in the bottom surface, and an upper surface of the diffusion member supporting a lower surface of the diffusion member to prevent the diffusion member from sagging; Backlight assembly for a liquid crystal display comprising a. The method of claim 1, And the diffusion plate deflection preventing member has a plate shape. The backlight assembly of claim 2, wherein an upper surface of the plate-shaped diffusion plate deflection preventing member is in contact with the diffusion member over an entire surface of the upper surface. The backlight assembly of claim 2, wherein an upper surface of the diffusion plate deflection prevention member has a triangular plate shape such that only a part of the upper surface contacts the diffusion member. The backlight assembly of claim 2, wherein a lower surface of the diffusion plate deflection prevention member is fixed to a bottom surface of the storage container by using a locking protrusion. The backlight assembly of claim 1, wherein the diffusion plate deflection prevention member is made of a transparent material capable of transmitting light from the lamp. The backlight assembly of claim 1, wherein the diffusion plate deflection prevention member is made of a silicone rubber having a hardness higher than that of the diffusion member.