KR20060032345A - A back light assembly for a liquid crystal display device - Google Patents

Abstract

The present invention relates to a backlight assembly capable of preventing protrusion between the lamp housing and the lower cover by forming protrusions and grooves on a contact surface between the lamp housing and the lower cover, the light source comprising: at least one light source provided on a rear surface of the liquid crystal panel; A lamp housing surrounding the light source and having an opening formed at one side thereof; A light guide plate provided on one side of the light source corresponding to the opening; A mold frame accommodating and supporting the liquid crystal panel, the light source, the lamp housing and the light guide plate; An upper cover coupled to an upper portion of the mold frame; A lower cover coupled to a lower portion of the mold frame and in contact with the lamp housing; And a pair of grooves and protrusions formed on a contact surface between the lamp housing and the lower cover to prevent flow between the lamp housing and the lower cover.

LCD, backlight, lamp housing, bottom cover, screw

Description

Back light assembly {A back light assembly for a liquid crystal display device}

1 is a block diagram of a conventional edge-type backlight assembly

2 is a block diagram of a backlight assembly according to a first embodiment of the present invention;

3 is a configuration diagram of a backlight assembly according to a second embodiment of the present invention;

4 is a cross-sectional view taken along line I-I of FIG. 3 as viewed in the direction of the arrow.

5 is a view for explaining a coupling relationship between the lamp housing and the lower cover of FIG.

* Explanation of symbols on the main parts of the drawings

206: mold frame 204: top cover

205: lower cover 207: lamp

208 lamp housing 220 wire

209: Reflector 201: Light guide plate

203: Optical sheet 203a: Diffusion sheet

203b: first light collecting sheet 203c: second light collecting sheet

203d: Protective sheet 200: Liquid crystal panel

211: projection 266: groove

The present invention relates to a backlight assembly of a liquid crystal display device, and more particularly, to a backlight assembly capable of preventing protrusion between the lamp housing and the lower cover by forming protrusions and grooves in a contact surface between the lamp housing and the lower cover.

In recent years, research on flat panel display devices has been actively conducted. Among them, liquid crystal display devices (LCDs), field emission display devices (FEDs), electro-luminescence display devices (ELDs), and PDPs (PDPs) Plasma Display Pannels).

Among them, LCD is the most widely used as a substitute for CRT (Cathode Ray Tube) for the use of mobile image display device because of the excellent image quality, light weight, thinness, and low power consumption, and mobile type such as monitor of notebook computer. In addition, it is being developed in various ways such as a monitor of a television and a computer for receiving and displaying broadcast signals.

As described above, although various technical advances have been made in order for the liquid crystal display device to serve as a screen display device in various fields, the task of improving the image quality as the screen display device has many advantages and disadvantages.

Therefore, in order for a liquid crystal display device to be used in various parts as a general screen display device, the key to development is how much high quality images such as high definition, high brightness, and large area can be realized while maintaining the characteristics of light weight, thinness, and low power consumption. It can be said.

Such a liquid crystal display device may be broadly divided into a liquid crystal panel displaying an image and a driving unit for applying a driving signal to the liquid crystal panel, wherein the liquid crystal panel includes a first and second substrates having spaces, and It consists of a liquid crystal layer injected between a 1st board | substrate and a 2nd board | substrate.

On the other hand, such a liquid crystal display device itself is non-luminescent, so a separate external light source for irradiating light is required.

In particular, in the case of a transmissive liquid crystal display, a separate dimming device that emits light and guides the back of the liquid crystal panel is required.

The back light includes an edge type and a direct type.

In the direct type, a light emitting lamp is disposed on a flat surface. Since the shape of the light emitting lamp appears on the liquid crystal panel, the gap between the light emitting lamp and the liquid crystal panel should be maintained, and light scattering means should be disposed for the uniform distribution of light quantity. Therefore, there is a limit to thinning.

In addition, as the liquid crystal panel becomes larger, the area of the light exit surface of the backlight is also increased. When the direct backlight is enlarged, the light exit surface is not flat unless the light scattering means secures sufficient thickness. Therefore, the thickness of the light scattering means must be sufficiently secured.

On the other hand, the edge type is to install a light emitting lamp on the outside and to distribute the light to the entire surface using a light guide plate, the light emitting lamp is installed on the side, there is a problem that the brightness is low because the light must pass through the light guide plate. In addition, high optical design and processing techniques for the light guide plate are required for uniform distribution of luminance.

Since the direct type and edge type have their disadvantages, the direct type backlight is mainly used in the liquid crystal display device where brightness is more important than the screen thickness, and the thickness such as a notebook PC or a monitor PC is important. In the liquid crystal display device, an edge type backlight is mainly used.

1 is a block diagram of a conventional edge-type backlight assembly.

In the conventional backlight assembly, as shown in FIG. 1, a plurality of lamps 107 for generating light and a light guide plate for guiding the light to the display unit side of the liquid crystal panel 100 by changing a path of the light ( 101, an optical sheet 103 for uniformizing the luminance of the light passing through the light guide plate 101, and light leaking from the light guide plate 101 under the light guide plate 101. And a reflector plate 109 for reflecting the light 101 to increase the efficiency of light, and a lamp housing 108 that forms a U-shape to have an opening opening toward the light guide plate 101 and surrounds the lamps 107. do.

Specifically, the lamp housing 108 is coupled to one side of the light guide plate 101 while surrounding the lamps 107, and blocks the light emitted from the lamps 107 from leaking. That is, since the light emitted from the lamps 107 is emitted radially, light that is not directed directly to the light guide plate 101 is reflected by the inner surface of the lamp housing 108 and transmitted to the light guide plate 101.

On the other hand, the optical sheet 103 is a diffusion sheet 103a for emitting the light passing through the light guide plate 101 as a light having an even luminance distribution, and the light passing through the diffusion sheet 103a is different from each other The first and second light collecting sheets 103b and 103c for condensing in the direction to secure a viewing angle, and a protective sheet 103d provided on the second light collecting sheet 103c to block foreign substances from entering. .

In addition, the conventional backlight assembly is coupled to the mold frame 106 for receiving and supporting the above-mentioned components, and the upper portion of the mold frame 106 to prevent the liquid crystal panel 100 from being separated. The upper cover 104 and the lower cover 105 is coupled to the lower portion of the mold frame 106. Here, the lower cover 105 and the lamp housing 108 are coupled to each other by a screw 155. That is, the screw 155 is inserted into the groove 150 formed in the contact surface between the lower cover 105 and the lamp housing 108 to fasten between the lower cover 105 and the lamp housing 108, thereby Prevents flow between the lower cover 105 and the lamp housing 108. On the other hand, one side of the lamp housing 108 facing the mold frame 106 is recessed into the lamp housing 108, so that the space between the mold frame 106 and the lamp housing 108 The wire 120 is formed in the space to transfer a driving voltage to the lamps 107.

However, the conventional backlight assembly has the following problems.                         

In the conventional backlight assembly, since the lower cover and the lamp housing are coupled to each other by the screw, the assembly is cumbersome and there is a problem in that work efficiency is lowered. In addition, since the screw must be used separately, there is a problem in that an increase in cost occurs due to the use of the screw.

The present invention has been made in order to solve the above problems, by forming a pair of grooves and projections on the contact surface between the lamp housing and the lower cover, the lamp housing and the lower cover is simplified without using a separate screw It is an object of the present invention to provide a backlight assembly that can be easily coupled.

The backlight assembly according to the present invention for achieving the above object, at least one light source provided on the back of the liquid crystal panel; A lamp housing surrounding the light source and having an opening formed at one side thereof; A light guide plate provided on one side of the light source corresponding to the opening; A mold frame accommodating and supporting the liquid crystal panel, the light source, the lamp housing and the light guide plate; An upper cover coupled to an upper portion of the mold frame; A lower cover coupled to a lower portion of the mold frame and in contact with the lamp housing; And a pair of grooves and protrusions formed on a contact surface between the lamp housing and the lower cover to prevent flow between the lamp housing and the lower cover.

Hereinafter, a backlight assembly according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

2 is a block diagram of a backlight assembly according to a first embodiment of the present invention.                     

As shown in FIG. 2, the backlight assembly according to the first embodiment of the present invention surrounds a plurality of lamps 207 provided at an edge of a rear surface of the liquid crystal panel 200, and the lamps 207. And a lamp housing 208 having an opening formed at one side thereof, and provided at one side of the lamps 207 corresponding to the opening, and reflected from the lamp housing 208 and the light emitted from the lamps 207. The light guide plate 201 for guiding the light path to the display unit side of the liquid crystal panel 200, the liquid crystal panel 200, the lamps 207, the lamp housing 208, and the light guide plate 201 are housed and supported. A mold frame 206, an upper cover 204 coupled to an upper portion of the mold frame 206, and a lower cover coupled to a lower portion of the mold frame 206 and in contact with the lamp housing 208 ( 205 and the contact surface between the lamp housing 208 and the lower cover 205 And a pair of grooves 266 and protrusions 211 to prevent flow between the lamp housing 208 and the lower cover 205.

Here, one side of the lamp housing 208 facing the mold frame 206 is recessed inside the lamp housing 208, so that a space is formed between the mold frame 206 and the lamp housing 208. The wire 220 is formed in the space to transfer a driving voltage to the lamps 207. In addition, an optical sheet 203 is provided between the light guide plate 201 and the liquid crystal panel 200 to uniformly transmit luminance of the light passing through the light guide plate 201 to the liquid crystal panel 200. . The optical sheet 203 includes a diffusion sheet 203a for emitting light passing through the light guide plate 201 to light having an even luminance distribution, and a light passing through the diffusion sheet 203a in different directions. The first and second light collecting sheets 203b and 203c for condensing the light to secure a viewing angle, and a protective sheet 203d provided on the second light collecting sheet 203c to block foreign substances from entering. In addition, a reflection plate 209 is provided between the light guide plate 201 and the lower cover 205 to reflect light leaking from the light guide plate 201 to the light guide plate 201 to increase light efficiency.

On the other hand, the protrusion 211 is formed on the rear surface of the lamp housing 208 facing the lower cover 205, the groove 266 is the lower cover 205 facing the lamp housing 208 It is formed on the upper surface of). Therefore, when the lamp housing 208 and the lower cover 205 are coupled, the projection 211 formed in the lamp housing 208 is inserted into the groove 266 of the lower cover 205, the lamp housing 208 and the lower cover 205 are tightly coupled to each other. As a result, it is possible to avoid the flow between them by simply combining the lamp housing 208 and the lower cover 205 to avoid the complicated manner of fastening using a separate screw as in the prior art.

Meanwhile, the protrusion 211 may be manufactured in a hook shape to further increase the coupling force between the lamp housing 208 and the lower cover 205. If this is explained in more detail as follows.

3 is a configuration diagram of a backlight assembly according to a second embodiment of the present invention, FIG. 4 is a cross-sectional view taken along line I to I when FIG. 3 is viewed in an arrow direction, and FIG. 5 is a lamp housing of FIG. And a view for explaining the coupling relationship between the lower cover.

As shown in FIGS. 3 and 4, the backlight assembly according to the second embodiment of the present invention includes a plurality of lamps 307 provided at the edge of the rear surface of the liquid crystal panel 300, and the lamps 307. ) And a lamp housing 308 having an opening formed at one side thereof, and provided at one side of the lamps 307 corresponding to the opening, and the light emitted from the lamps 307 and the lamp housing 308. The light guide plate 301 and the liquid crystal panel 300, the lamps 307, the lamp housing 308, and the light guide plate 301 for changing the path of the light reflected from the light guide to the display unit side of the liquid crystal panel 300. A mold frame 306 for receiving and supporting the upper surface, an upper cover 304 coupled to an upper portion of the mold frame 306, and a lower portion of the mold frame 306, contacting the lamp housing 308. A lower cover 305 and between the lamp housing 308 and the lower cover 305 Is formed on chokmyeon, it is configured to include a pair of grooves 366 and projections 311 of the hook shape to prevent flow between the lamp housing 308 and the lower cover (305).

 Here, one side of the lamp housing 308 facing the mold frame 306 is recessed inside the lamp housing 308, so that a space is formed between the mold frame 306 and the lamp housing 308. The wire 330 is formed in the space to transfer a driving voltage to the lamps 307. In addition, an optical sheet 303 is provided between the light guide plate 301 and the liquid crystal panel 300 to uniformly transmit luminance of the light passing through the light guide plate 301 to the liquid crystal panel 300. . The optical sheet 303 includes a diffusion sheet 303a for emitting the light passing through the light guide plate 301 as light having an even luminance distribution, and a light passing through the diffusion sheet 303a in different directions. The first and second light collecting sheets 303b and 303c for condensing and securing a viewing angle, and a protection sheet 303d provided on an upper portion of the second light collecting sheet 303c to block foreign substances from entering. In addition, a reflection plate 309 is provided between the light guide plate 301 and the lower cover 305 to reflect light leaking from the light guide plate 301 to the light guide plate 301 to increase light efficiency.

As shown in Figures 3 and 4, the protrusion 311 is bent one end thereof, thereby forming a hook shape as a whole. The protrusion 311 is formed at a rear surface of the lamp housing 308 facing the lower cover 305, and the groove 366 is formed at the lower cover 305 facing the lamp housing 308. Formed. In detail, the groove 366 is formed to penetrate the lower cover 305. Therefore, when the lamp housing 308 and the lower cover 305 are coupled, the projection 311 formed in the lamp housing 308 is inserted into the groove 366 of the lower cover 305 and the The bent end of the projection 311 comes into contact with the back of the lamp housing 308. Accordingly, the lower cover 305 is firmly fitted between the end of the protrusion 311 and the lamp housing 308 in which the protrusion 311 is formed. As a result, it is possible to avoid the flow between them by simply combining the lamp housing 308 and the lower cover 305 to avoid the complicated manner of fastening using a separate screw as in the prior art.

Here, the coupling between the lamp housing 308 and the lower cover 305 shown in FIG. 4 will be described in more detail. First, the lamp housing 308 is mounted on the upper surface of the lower cover 305 so that the protrusions 311 and the grooves 366 are spaced apart from each other by a predetermined interval. That is, the lamp housing 308 is not positioned to correspond to the lower cover 305, but is placed on the lower cover 305 in a state slightly displaced from the lower cover 305. Accordingly, the bent end of the protrusion 311 is in contact with the upper surface of the lower cover 305 without being inserted into the groove 366. Thereafter, the lamp housing 305 is moved in one direction so that the protrusion 311 meets the groove 305. At this time, the protrusion 311 is inserted into the groove 305 so that the bent end of the protrusion 311 comes into contact with the rear surface of the lower cover 305.

The present invention described above is not limited to the above-described embodiment and the accompanying drawings, and it is common in the art that various substitutions, modifications, and changes can be made without departing from the technical spirit of the present invention. It will be evident to those who have knowledge of.

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

In the backlight assembly of the present invention, a pair of grooves and protrusions are formed on the contact surface between the lamp housing and the lower cover, thereby preventing the flow between the lamp housing and the lower cover. Accordingly, the lamp housing and the lower cover can be simply combined by removing a complicated method of fastening using a separate screw as in the related art.

In addition, by making the protrusions in the form of hooks, it is possible to more effectively prevent the flow between the lamp housing and the lower cover.

Claims (5)

At least one light source provided on a rear surface of the liquid crystal panel; A lamp housing surrounding the light source and having an opening formed at one side thereof; A light guide plate provided on one side of the light source corresponding to the opening; A mold frame accommodating and supporting the liquid crystal panel, the light source, the lamp housing and the light guide plate; An upper cover coupled to an upper portion of the mold frame; A lower cover coupled to a lower portion of the mold frame and in contact with the lamp housing; And And a pair of grooves and protrusions formed on a contact surface between the lamp housing and the lower cover to prevent flow between the lamp housing and the lower cover. The method of claim 1, The protrusion is formed on the rear surface of the lamp housing facing the lower cover, the groove is formed on the upper surface of the lower cover facing the lamp housing. The method of claim 2, The protrusion has a hook shape, and the groove is formed to penetrate the lower cover. The method of claim 1, And between the light guide plate and the liquid crystal panel an optical sheet for uniformly transmitting the brightness of the light passing through the light guide plate to the liquid crystal panel. The method of claim 1, And a reflection plate between the light guide plate and the lower cover to reflect the light leaked from the light guide plate to the light guide plate.

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