KR100679494B1 - Backlight assembly for lcd - Google Patents

Abstract

A coupling structure of a backlight unit in an LCD is provided to uniformly maintain the distance between a fluorescent lamp and a light guiding plate by using a guide member, and prevent the positional change of the fluorescent lamp and the light guiding plate by using a position fixing member. A backlight unit comprises a fluorescent lamp(30), a light guiding plate(40), a reflecting plate(20), and optical sheets. A cover bottom(10) has at least one guide member(11') for placing the reflecting plate, the light guiding plate, and the optical sheets in positions. A guide panel(60) has at least one position fixing member(12) for fixing the light guiding plate, the reflecting plate, and the optical sheets. The guide panel is coupled with the guide panel. The position fixing member is capable of being formed on the cover bottom.

Description

Backlight Assembly for LCDs {Backlight Assembly for LCD}

1 is an exploded perspective view of a coupling structure of a conventional LCD backlight;

2 is a view showing a middle holder in a combined structure of a conventional LCD backlight;

3 is an exploded perspective view of the coupling structure of the backlight for the LCD according to an embodiment of the present invention,

4 is an exploded perspective view showing a coupling structure of a backlight for an LCD according to another embodiment of the present invention;

5 is a view showing a detailed perspective view of the structure of the cover bottom guide portion in the cover bottom according to an embodiment of the present invention,

6 is a detailed perspective view of the structure of the position fixing part in the cover bottom according to an embodiment of the present invention,

7 is a plan view showing a coupling structure of a backlight for an LCD according to an embodiment of the present invention;

8 is a plan view showing a coupling structure of the backlight for the LCD according to another embodiment of the present invention.

** Description of symbols for the main parts of the drawing **

10: Cover Bottom 20: Reflector

30 fluorescent lamp 40 light guide plate

50: sheets 60: guide panel

11: middle holder 11 ': cover bottom guide part

12: position fixing 11a, 12a: rubber pad

The present invention relates to a backlight coupling structure of a liquid crystal display device, and more particularly, a cover bottom guide part and a position fixing part to prevent a fluorescent lamp, a light guide plate, and various light sheets from being positioned and flowed in a cover bottom. It relates to a backlight coupling structure for an integrally formed liquid crystal display device.

Recently, as the information society develops, the demand for display devices is increasing in various forms. Accordingly, liquid crystal displays (LCDs), PDPs (Plasma Display Panels), and ELDs (Electro Luminescent Display) ) And various flat panel display devices such as VFD (Vacuum Fluorescent Display) have been researched and utilized. Here, LCD is widely used as a mobile flat panel display device because of its excellent image quality, light weight, thinness, and low power consumption. In particular, LCD is widely used as a notebook, computer monitor, and monitor of various video devices.

However, such LCDs do not emit light by themselves and require a separate external light source to realize a high quality image. Therefore, the LCD structure further includes a backlight unit as a light source of the liquid crystal display panel in addition to the liquid crystal display panel, so that the backlight unit uniformly supplies a high brightness light source to the front of the LCD to realize a high quality image. As a backlight or illumination light source for a flat panel display such as an LCD, a flat lamp element having high brightness and capable of displaying various colors is an AC-driven plasma display panel (PDP) device, an electro luminescence (EL) device, or an LED (Light Emitting). Diode elements, CCFLs (Cold Cathode Fluorescent Lamps), HCFLs (Hot Cathode Fluorescent Lamps), and the like are frequently used. In particular, CCFL fluorescent lamps, which have a long lifespan, low power consumption, and can be formed thinly, are widely used as backlights of large screen LCDs.

The CCFL fluorescent lamp is filled with a mixed gas such as argon (Ar), helium (He), neon (Ne), xenon (Xe) or mercury (Hg) in a discharge tube, and electrodes are formed at both ends of the discharge tube. When a voltage is applied through the discharge gas in the discharge tube emits ultraviolet rays by the plasma phenomenon, the ultraviolet rays excite the phosphor formed on the inner surface of the reaction tube to emit visible light to the LCD screen to function as a backlight.

The backlight using the CCFL fluorescent lamp is composed of a direct type in which several fluorescent lamps are installed at the bottom of the LCD panel to directly illuminate the screen, and are installed at both ends of the LCD panel to be screened by light guide plates, reflecting plates, and various light sheets. It is divided into a method consisting of an edge type that illuminates, and currently, the edge method is mainly used.

A conventional backlight coupling structure for the above edge method will be described in detail with reference to FIGS. 1 to 2.

Figure 1 shows an exploded perspective view of a conventional backlight coupling structure for LCD. Referring to FIG. 1, a backlight generally includes a cover bottom 10 and a guide panel 60 including various components therein, a fluorescent lamp 30 that emits visible light by an external voltage, and a visible light of the fluorescent lamp. Light guide plate 40 for emitting light toward the panel side, reflector plate 20 for reflecting light of the light guide plate forward, and various sheets 50 for improving the brightness of light from the light guide plate to the liquid crystal display panel (not shown). It is done by

In the combined structure of the backlight having such a configuration, the reflecting plate 20, the light guide plate 40, and various sheets 50 are sequentially stacked on the cover bottom 10, and the fluorescent lamp 30 has a side edge of the light guide plate 40. It is disposed in a wrapping form, and the guide panel 60 is combined with the cover bottom 10 to complete the combination of the backlight for the LCD. The light guide plate 40 functions as a surface light source in the backlight. The fundamental light source is visible light emitted from the fluorescent lamp 30 having a 'b' shape or a 'c' shape, and is not enclosed by the fluorescent lamp 30. The remaining side cross-section of the 40 is attached with a reflector 41 to prevent light from being emitted to the outside.

On the other hand, the light guide plate 40 is expanded by the high temperature heat generated from the lamp 30, so that a predetermined margin is provided between the fluorescent lamp 30 and the light guide plate 40 in consideration of the thermal expansion rate of the light guide plate 40. It must be designed. In this case, when an external shock or vibration is given in a state where the lamp is not turned on, the fluorescent lamp 30 or the light guide plate 40 moves by these clearances, and eventually the positional distance between the light guide plate side surface and the fluorescent lamp is changed. It is losing or changing. Thus, when the fluorescent lamp 30 and the light guide plate 40 emit light in a state where the light guide plate 40 is not in a correct position, uniform luminance according to the original purpose may not be generated. Since the distance difference between the fluorescent lamp 30 and the light guide plate 40 has a serious effect on the brightness of the backlight and the uniformity of the brightness, the guide means for positioning the fluorescent lamp 30 or the light guide plate 30 and It should be fixed at a certain position with fixing means to prevent flow by thermal expansion or external vibration.

Referring to FIG. 2, in order to solve this problem, the fluorescent lamp 30 and the light guide plate 40 may be fixed to the cover bottom 10 so that the cover bottom 10 may be a middle holder 11 as a separate guide means. ) Is attached. The middle holder 11 is positioned at the corner of the cover bottom 10 to support the fluorescent lamp 30 and the light guide plate 40 to be fixed in place. The shape of the middle holder 11 forms a double wall structure having a rounded right angle so that the fluorescent lamp 30 is positioned in the space between the outer wall and the inner wall, and the inner wall allows the light guide plate 40 to come into contact with the fluorescent lamp 30 and the light guide plate. It is comprised so that 40 may be located.

However, in the conventional backlight coupling, by manufacturing the middle holder separately and attaching it to the cover bottom, the combination of the backlight is complicated and the manufacturing cost is increased by the manufacturing process and the attachment process of the middle holder. In addition, the positional shift or change due to thermal expansion or external vibration cannot be prevented, and thus there is a problem of lowering the luminance of the backlight and the uniformity of the luminance.

The present invention has been proposed to solve the above problems, by providing a guide means for fixing the fluorescent lamp and the light guide plate in the cover bottom to be fixed so that the fluorescent lamp and the light guide plate can be positioned at a constant interval. It is an object of the present invention to provide a backlight coupling structure capable of securing a uniform luminance characteristic as a surface light source by preventing the position from being changed or changed by thermal expansion or external vibration by providing the position fixing means together.

It is another object of the present invention to provide a backlight coupling structure in which the position guide means and the position fixing means are integrally formed on the cover bottom, thereby simplifying the structure and manufacturing process and reducing the cost.

In order to achieve the above object, a backlight coupling structure for a liquid crystal display device of the present invention includes a fluorescent lamp for emitting visible light by an external power source, and the visible light of the fluorescent lamp is introduced into a side surface to emit light as a surface light source. A light guide plate, a reflection plate for reflecting the surface light source of the light guide plate to the front of the backlight device under the light guide plate, various sheets for condensing and diffusing the surface light source on the upper side of the light guide plate, the fluorescent lamp, the light guide plate, the reflection plate, various A cover bottom integrally formed with at least one cover bottom guide part for aligning the sheets and at least one position fixing part for fixing the light guide plate, the reflecting plate, and various sheets are integrally formed and combined with the cover bottom. The panel is configured to include the fluorescent lamp, the light guide plate, the reflector plate, and various sheets in the cover bottom. Characterized in that for fixing the position.

In addition, the backlight coupling structure of the present invention, the position fixing portion may be integrally formed on the cover bottom together with the cover bottom guide portion, the cover bottom guide portion and the position fixing portion is bent and raised by bending the bottom of the cover bottom Characterized in that formed integrally with the cover bottom.

In addition, the cover bottom guide portion and the position fixing portion is characterized in that the pad having elasticity is covered or attached.

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

3 and 4 show an exploded perspective view of the backlight coupling structure for the LCD according to an embodiment of the present invention.

The LCD backlight of the present invention includes a cover bottom (10) formed integrally with a cover bottom guide portion (11 ') for positioning the respective components, a reflecting plate (20) for reflecting light to the front of the backlight device, A fluorescent lamp 30 disposed along the side of the light guide plate to emit visible light by an external power source, a light guide plate 40 for injecting visible light of the fluorescent lamp into a side surface to emit light as a surface light source, and condensing light guided from the light guide plate And a guide panel coupled to the cover bottom 10 by attaching a position fixing part 12 to fix various sheets 50 and a position of each component to be transferred to a liquid crystal display panel (not shown). 60). The position fixing part 12 may be attached to the guide panel 60 or to the cover bottom 10.

By such a configuration, the cover bottom includes various components in the backlight such as a fluorescent lamp, a reflecting plate, a light guide plate, and various sheets, and is combined with the guide panel. The liquid crystal display device functions as a display device by mounting a liquid crystal display panel above the combined backlight structure.

Referring to FIG. 3, the cover bottom 10 has a cover bottom guide portion 11 ′ for aligning each component stacked therein. The cover bottom guide part 11 ′ is formed by bending the bottom of the cover bottom 10 to be bent and raised, and the corner portion of the cover bottom 10 is located between the fluorescent lamp 30 and the corner of the light guide plate 40. It is preferable to be formed in accordance with the shape of the corner portion of the fluorescent lamp 30, one or more can be formed according to the shape of the fluorescent lamp 30, in the case of the 'b' shaped fluorescent lamp 30 It may be formed in the corner portion of, 'C' shaped fluorescent lamp 30 may be formed in two corner portions.

The reflector 20 is for reflecting light from the light guide plate 30 to the liquid crystal display panel and is positioned below the light guide plate 40. In addition, the groove 21 is formed in the corner portion so that the reflecting plate 20 can be fitted to the cover bottom guide portion 11 ′ according to the shape of the cover bottom guide portion 11 ′ so that the reflecting plate 20 is positioned in the cover bottom 10. Can be formed.

The fluorescent lamp 30 is positioned to surround the side end surface of the light guide plate 40 so that visible light generated from the lamp 30 may flow into the side end surface of the light guide plate 40, and the cover bottom guide part 11 ′ is provided. It is positioned in the cover bottom 10 by the.

The light guide plate 40 is stacked on the upper side of the reflecting plate 20 to introduce visible light generated from the fluorescent lamp 30 into the side cross-section to convert light into a surface light source, and the corner portion is covered by the cover bottom guide portion 11 '. The sides are diagonally shaped so as to be positioned. Meanwhile, since the fluorescent lamp 30 is generally positioned to surround the side surface of the light guide plate 40 in a 'b' shape or a 'c' shape, the side surface of the light guide plate 30 which is not covered by the fluorescent lamp 30 Reflective paper 41 is attached. The luminance of the backlight may be further improved by preventing the visible light flowing into the light guide plate 40 by the reflecting paper 41 from leaking to the outside of the side surface of the light guide plate 40.

Above the light guide plate 40, various sheets 50 for condensing and diffusing light generated from the light guide plate 40 with the liquid crystal display panel are positioned. Sheets 50, such as the light guide plate 40 in order to be positioned in the cover bottom 10 is formed in a diagonal shape.

The guide panel 60 is combined with the cover bottom 10 including the above-described components to form a backlight coupling structure. Several protrusions are formed on the outer surface of the guide panel 60 and are fitted into the grooves formed on the side surfaces of the cover bottom 10, thereby engaging the cover bottom 10.

In addition, the position fixing part 12 for fixing each component is formed inside the guide panel 60, and when coupled with the cover bottom 10, by supporting the side of each component, vibration or external impact As a result, the light guide plate 40 and the various sheets 50 and the like are not twisted or changed in position. In this case, since the light guide plate 40 is finely thermally expanded by the heat of the fluorescent lamp 30, the position fixing part 12 preferably has elasticity to support the light guide plate in response to such thermal expansion. Therefore, it is made of a plastic or rubber material having elasticity and heat resistance, attached to the guide panel 60, or formed integrally with the guide panel, if it does not have elasticity to cover the rubber pad having elasticity (see 12a of FIG. 6). Can be configured. The position fixing part 12 should be positioned on the side of the light guide plate 40 to which the reflecting paper 41 is attached so as not to affect the brightness of the backlight.

In the practice of the present invention, the position fixing part 12 may be formed in the guide panel 60 as shown in FIG. 3, but may be formed in the cover bottom 10 as shown in FIG. 4. Even when the cover bottom 10 is formed, it may be made of a material having elasticity and may be attached like the guide panel 60, but the cover bottom 10 may be formed by the same process of forming the cover bottom guide part 11 ′. It is preferable to be formed integrally with the cover bottom 10 by bending and bending the bottom surface (see Fig. 6).

5 shows a detailed structure of the cover bottom guide portion in the cover bottom according to an embodiment of the present invention, Figure 6 shows a detailed structure of the position fixing.

Referring to FIG. 5, the cover bottom guide part 11 ′ according to the embodiment of the present invention is integrally formed by bending and bending the bottom surface of the cover bottom 10. Therefore, according to the present invention, since the middle holder manufacturing process and the process of attaching the middle holder 11 to the cover bottom 10 are not required as compared with the conventional backlight structure requiring a separate middle holder 11, the structure and the process are Simple. In addition, the cover bottom guide portion 11 ′ may be formed in the shape of a corner portion of the lamp by cutting a part of the outer side of the bottom surface which is bent and bent and bent inward. Alternatively, the bottom surface of the cover bottom 10 may be bent to be positioned at side surfaces of adjacent fluorescent portions of the fluorescent lamp or the light guide plate, which may be formed at right angles, or may be simultaneously formed on the outside together with the inside of the corner portions of the fluorescent lamp 30 ( end). Or it may be bent at both corners adjacent to the corner of the fluorescent lamp (b).

Referring to FIG. 6, the position fixing part 12 is also integrally formed by bending and bending the bottom surface of the cover bottom in the same manner as the cover bottom guide part 11 ′.

Here, the cover bottom guide part 11 'and the position fixing part 12 are covered with rubber pads 11a and 12a having elasticity and heat resistance, or attached to the inner surface thereof, whereby the light guide plate is formed by heat generated from the fluorescent lamp 30. Even when 40 is expanded, a space for thermal expansion may be secured to further prevent the light guide plate 40 from being twisted or changed in position. In addition, by attaching the resilient pads (11a, 12a) it is possible to combine the light guide plate 40 having a fine size difference without mapping separately to fit the size.

7 illustrates a coupling structure of an LCD backlight according to an embodiment of the present invention, and FIG. 8 is a plan view illustrating a coupling structure of an LCD backlight according to another embodiment of the present invention.

Referring to FIG. 7, when the fluorescent lamp 30 has a 'c' shape, the cover bottom guide part 11 ′ is formed at two corners of the fluorescent lamp 30, and lamps are formed at both ends of the lamp 30. Position fixing portion 12 for fixing the is further formed. When the position fixing part 12 is further formed at both ends of the lamp, since the long lamp has some elasticity, the lamp 30 is more firmly fixed by this elasticity.

On the other hand, the position fixing part 12 for fixing the light guide plate 40 is also formed on one side of the light guide plate 40 which is not wrapped in the fluorescent lamp 30. The position fixing part 12 supports to prevent the light guide plate 40 positioned by the cover bottom guide part 11 'from being twisted or changed in position by external vibration or thermal expansion.

8 shows a fluorescent lamp 30 formed in a 'b' shape, and the cover bottom guide part 11 'is formed at one corner of the fluorescent lamp 30, and the position fixing parts 12 are formed at both ends. do. In this case, the position fixing part 12 for fixing the light guide plate 40 is preferably formed on two side surfaces of the light guide plate 40.

Although the present invention has been described in detail through specific embodiments, the present invention is not limited to the above-described embodiments and variously modified and implemented by those skilled in the art to which the present invention pertains without departing from the spirit of the present invention. Can be.

As described above, the fluorescent lamp and the light guide plate can be positioned at regular intervals by the cover bottom guide part for fixing the fluorescent lamp and the light guide plate to the cover bottom so as to be fixed. By preventing the position from being changed or changed due to external vibration or the like, it is possible to ensure uniform luminance characteristics as the surface light source. In addition, the cover bottom guide portion and the position fixing portion are formed integrally with the cover bottom, the manufacturing process can be simple and cost can be reduced.

Claims (8)

In the backlight coupling structure, Fluorescent lamp for emitting visible light by an external power source; A light guide plate in which visible light of the fluorescent lamp flows into a side cross section and emits light as a surface light source; A reflection plate for reflecting the surface light source of the light guide plate to the front of the backlight device under the light guide plate; Various sheets for condensing and diffusing a surface light source on an upper side of the light guide plate; A cover bottom integrally formed with at least one cover bottom guide part for aligning the fluorescent lamp, the light guide plate, the reflecting plate, and various sheets; And A guide panel which is integrally formed with one or more position fixing parts for fixing the light guide plate, the reflecting plate, and various sheets; It is configured to include, the backlight coupling structure, characterized in that for fixing the fluorescent lamp, the light guide plate, the reflecting plate, various sheets in a fixed position in the cover bottom. The backlight coupling structure for a liquid crystal display device according to claim 1, wherein the position fixing part is formed on the cover bottom. The backlight coupling structure for a liquid crystal display device according to claim 2, wherein the position fixing part is formed by bending the bottom surface of the cover bottom to be bent up and integrally formed on the cover bottom. The backlight coupling structure for a liquid crystal display device according to claim 1, wherein the cover bottom guide portion is bent and bent up the bottom surface of the cover bottom to be integrally formed with the cover bottom. The liquid crystal display according to claim 4, wherein the cover bottom guide portion is formed in accordance with a shape of a corner portion of the fluorescent lamp by bending a bottom surface of the cover bottom and cutting a portion of the bottom bottom surface which is bent and bent inward. Backlight coupling structure for display device. The backlight coupling structure for a liquid crystal display device according to claim 4, wherein the cover bottom guide part is formed at each of adjacent side edges of the fluorescent lamp corner. 5. The backlight coupling structure of claim 4, wherein the cover bottom guide part is formed inside and / or outside the corner of the fluorescent lamp. 6. The backlight coupling structure of claim 1, wherein the cover bottom guide part and the position fixing part are formed by covering or attaching a pad having elasticity.

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