KR20080028581A - Light guide plate, backlight assembly and liquid crystal display device having same - Google Patents

Abstract

According to an exemplary embodiment of the present invention, a light guide plate used in a liquid crystal display includes at least one seating portion formed in a stepped shape on an upper surface thereof and a receiving recess formed in one side of the lower surface thereof.

The invention as described above has the effect of preventing the occurrence of a molding problem during the mold management and assembly of the mold frame and the light guide plate, the cost is reduced and the quality is improved. In addition, by removing and configuring the mold frame, assembly time and assembly can be simplified, and the thickness of the existing mold frame can be reduced.

Description

LIGHT GUIDEING PLATE AND A BACKLIGHT ASSEMBLY AND A LIQUID CRYSTAL DISPLAY HAVING THE SAME}

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

2 is a cross-sectional view illustrating A-A of FIG. 1.

3 is a plan perspective view showing a light guide plate according to the present invention.

4 is a rear perspective view of the light guide plate according to the present invention;

5 is a rear perspective view showing a modification of the light guide plate according to the present invention.

             <Description of the code | symbol about the principal part of drawings>

100: liquid crystal display panel 210: LED element

220: substrate 230: back cover

310: first seating portion 320: second seating portion

330: receiving groove 340: lower seating portion

400: reflective sheet 510: diffusion sheet

520: prism sheet 600: light leakage prevention member

The present invention relates to a light guide plate, a backlight assembly and a liquid crystal display device having the same, and more particularly, to manufacture a light guide plate and a mold frame integrally, to reduce the time required for assembly and to reduce the cost, and It relates to a backlight assembly and a liquid crystal display device provided.

In general, a flat panel display is an essential display device for realizing not only a monitor of a desktop computer but also a small and lightweight system such as a portable computer such as a notebook computer or a PDA or a mobile phone terminal. The flat panel display is a liquid crystal display (LCD). A liquid crystal display (PDP), a plasma display panel (PDP), a field emission display (FED), and the like. In particular, the liquid crystal display device has recently been spotlighted as a next-generation display device such as a monitor of a mobile phone, a computer, a television, etc., because the liquid crystal display device has excellent visibility and a smaller average power consumption than a CRT of the same image.

The liquid crystal display device described above includes a light source unit including a liquid crystal display panel for displaying an image, a light guide plate for irradiating uniform light to the liquid crystal display panel, a light source for injecting light from one side of the light guide plate, and a light source cover; The liquid crystal display panel, the light guide plate, and a mold frame for accommodating the light source unit are included, and the liquid crystal display device is manufactured by assembling the components.

However, when assembling the parts, there are many assembly processes, thereby causing a problem in that a tack time takes a long time.

In addition, scratches caused by interference between the components in the assembly process of the components cause defects of the liquid crystal display.

In order to solve the above problems, an object of the present invention is to provide a liquid crystal display device for reducing the assembly time and the time required for assembly by reducing the structure of the light guide plate and reducing the cost of parts.

In order to achieve the above object, the light guide plate of the present invention includes at least one seating portion formed in a stepped shape inward on the upper surface, and a receiving groove formed concave on one side of the lower surface.

The seating portion includes a first seating portion and a second seating portion, the first seating portion includes a first seating surface and a first sidewall bent vertically from the first seating surface, and the second seating portion is disposed at the first sidewall. And a second sidewall extending vertically outward and a second sidewall bent perpendicularly to the second seating surface.

The lower surface further comprises a lower seating portion formed spaced apart from the receiving groove.

In order to achieve the above object, the backlight assembly of the present invention comprises a light guide plate having at least one seating portion formed in a stepped shape inwardly on an upper surface thereof, a light source unit providing light to the light guide plate, and at least one housed in the seating portion. Optical sheet and a reflective sheet disposed below the light guide plate.

Further comprising a receiving groove formed on one side of the lower surface of the light guide plate, characterized in that the light source is accommodated in the receiving groove.

Further comprising a lower seating portion formed to the inner side of the lower surface of the light guide plate, characterized in that the lower seating portion accommodates the reflection sheet.

The light source unit may include an LED device, a substrate on which the LED device is mounted, and a back cover adhered to a lower portion of the substrate.

The back cover may include a cover base bonded to a substrate and a cover sidewall portion bent upward from the cover base, and the cover base and the cover sidewall portion may be formed to surround the lower side and the sidewall of the light guide plate.

In order to achieve the above object, the liquid crystal display device of the present invention is a light guide plate having a first seating portion and a second seating portion formed in a stepped shape inward on the upper surface, a light source unit for providing light to the light guide plate, and the light guide plate And a reflective sheet provided under the light emitting unit, an optical sheet mounted on the first mounting unit, and a liquid crystal display panel mounted on the second mounting unit.

Further comprising a receiving groove formed on one side of the lower surface of the light guide plate, characterized in that the light source is accommodated in the receiving groove.

Further comprising a lower seating portion formed spaced apart from the receiving groove, characterized in that the lower seating portion is accommodated in the reflective sheet.

The apparatus may further include a light leakage preventing member to block light emitted from the light guide plate.

The light leakage preventing member surrounds an upper portion and a side portion of the light guide plate.

The light leakage preventing member is formed in the second seating portion.

The light leakage preventing member is characterized in that the black tape or reflective sheet.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, and only the embodiments are intended to complete the disclosure of the present invention, and to those skilled in the art to fully understand the scope of the invention. It is provided to inform you. Like reference numerals in the drawings refer to like elements.

1 is an exploded perspective view illustrating a liquid crystal display according to the present invention, FIG. 2 is a cross-sectional view illustrating AA of FIG. 1, and FIGS. 3 and 4 are plan and perspective views showing a light guide plate according to the present invention, and FIG. 5. Is a rear perspective view showing a modification of the light guide plate according to the present invention.

Referring to FIG. 1, the liquid crystal display according to the present invention includes a liquid crystal display panel 100, a backlight assembly 1000 positioned under the liquid crystal display panel to provide light, and a liquid crystal display panel 100 of the liquid crystal display panel 100. The light leakage preventing member 600 surrounding the upper portion and the side wall of the backlight assembly 1000 is included.

The liquid crystal display panel 100 includes a color filter (CF) substrate 110 and a thin film transistor (TFT) substrate 120 disposed under the CF substrate 110.

The CF substrate 110 is a glass substrate in which a RGB pixel, which is a color pixel in which a predetermined color is expressed while light passes, is formed by a thin film process. A color filter is formed on one surface of the CF substrate 110 and an upper portion of the color filter. A common electrode made of a transparent conductor such as indium tin oxide (ITO) or indium zinc oxide (IZO) is coated.

The TFT substrate 120 is provided under the CF substrate 110 and is a transparent glass substrate on which TFTs in a matrix form are formed. A data line is connected to a source terminal of the TFTs, and a gate line is connected to a gate terminal. In the drain terminal, the pixel region is connected to a pixel electrode made of a transparent conductive material.

The CF substrate 110 and the TFT substrate 120 manufactured as described above are bonded through a bonding process, and a liquid crystal is injected between the CF substrate 110 and the TFT substrate 120.

Therefore, when the TFT is turned on by applying an electrical signal to the gate line and the source line of the TFT of the TFT substrate 120, an electric field is formed between the pixel electrode and the common electrode of the CF substrate 110. As a result, an electric field is formed between the CF substrate 110 and the TFT substrate 120. The arrangement angle of the liquid crystal injected between the CF substrate 110 and the TFT substrate 120 is changed by this electric field, and the light transmittance is changed according to the changed arrangement angle to obtain a desired image.

Although not shown in the drawings, a printed circuit board (PCB), not shown, for receiving an external signal on one side of the TFT substrate 120 to apply an electrical signal to the liquid crystal display panel 100. And a flexible printed circuit (FPC) (not shown) connecting the PCB and the TFT substrate 120 to transmit a signal applied from the PCB to the liquid crystal display panel.

In addition, a polarizing plate (not shown) that polarizes light incident on the liquid crystal display panel 100 may be further provided above the CF substrate 110 and below the TFT substrate 120.

The backlight assembly 1000 is disposed below the liquid crystal display panel 100 to provide uniform light to the liquid crystal display panel 100.

The backlight assembly 1000 may include a light source unit 200 for generating light, a light guide plate 300 for injecting light generated by the light source unit 200, a reflector plate 400 disposed below the light guide plate 300, The optical sheet 500 is provided on the light guide plate 300.

The light source unit 200 may fix a light emitting diode (LED) element 210, a substrate 220 on which the LED element 210 is mounted, and fix the LED element 210 and the substrate 220. And a back cover 230.

The LED device 210 is a side view type device, and emits light toward the side of the light guide plate 300. In addition, the substrate 220 is a flexible printed circuit board having excellent bending, and a circuit (not shown) is formed therein to supply external power to the LED device 210 through the circuit.

The back cover 230 serves to fix the LED element 210 and the substrate 220 on which the LED element 210 is mounted. The back cover 230 is 90 degrees above the cover base 230a and the cover base 230a. Bent cover sidewall portion 230b. The substrate 220 on which the LED device 210 is mounted is bonded to the cover base 230a, and in this case, the substrate 220 may be bonded using a double-sided tape or an adhesive. The cover base 230a and the cover sidewall portion 230b are disposed to cover a portion of the lower and side surfaces of the light guide plate 300. In this case, the LED element 210 is positioned at one side of the light guide plate 300. Therefore, the light emitted from the light source unit 200 is incident to the side of the light guide plate 300 and is emitted upward through the light guide plate 300.

In the drawing, the light source unit 300 is illustrated as being provided on one side of the light guide plate 300, but is not limited thereto. The light source unit 300 may be further provided on the other side facing one side of the light guide plate 300, and four corners of the light guide plate 300 may be provided. Of course it can also be provided.

The light guide plate 300 is generally made of a transparent material such as polymethy methacrylate (PMMA), polyolefin, or polycarbonate, which is an acrylic resin, and includes a first seating part 310 in which a plurality of optical sheets 500 may be accommodated. The LCD panel includes a second mounting part 320 on which the liquid crystal display panel 100 may be mounted, and a reflecting plate 400 is disposed below the light guide plate 300. An accommodation groove 330 is provided at a lower side of the light guide plate 300 so that the device 210 may be inserted. Therefore, the light guide plate 300 serves to change the light having the optical distribution of the point light source generated by the light source unit 200 to the light having the optical distribution in the form of a surface light source. The light guide plate 300 according to the present invention having the above configuration will be described in detail later with reference to the drawings.

The reflective plate 400 is provided under the light guide plate 300 and uses a plate having a high light reflectance. Although the reflective plate 400 is illustrated as having a flat shape, the reflective plate 400 may be manufactured to have a reference reflective surface and an inclined surface having a predetermined angle inclination from the reference reflective surface to increase the reflectance of the reflective plate 400.

The optical sheet 500 is sequentially seated on the first mounting portion 310 of the light guide plate 300 and includes a diffusion sheet 510 and at least one prism sheet 520.

The diffusion sheet 510 diffuses the light incident from the light guide plate 300 to have a uniform distribution in a wide range and irradiates the liquid crystal display panel 100. In this case, the diffusion sheet 510 may be omitted.

The prism sheet 520 is provided as a plurality of sheets on the diffusion sheet 510, and the light incident from the diffusion sheet 510 is perpendicular to the liquid crystal display panel 100 to display the light in a liquid crystal display. It serves to condense toward the panel 100. At this time, a protective sheet (not shown) may be further included to protect the surface of the prism sheet 520, and may be provided as one prism sheet 520.

The light leakage preventing member 600 includes a flat portion having a rectangular frame of an open rectangular shape and a side wall portion 600b bent downward from the flat portion 600a. The light leakage preventing member 600 is formed to cover an outer side of the liquid crystal display panel 100 and a side of the backlight assembly 1000 so that light emitted from the backlight assembly 1000 is external to the liquid crystal display panel 100. It plays a role of not leaking.

In this case, the light leakage preventing member 600 may use a frame member having a fixed shape. Also, a black tape or the like having no fixed shape may be attached to the outside of the liquid crystal display panel 100 and the side of the backlight assembly 1000. It may be formed. That is, the light leakage blocking tape may be bonded to a desired position without using a separate chassis member.

Meanwhile, as shown in FIGS. 3 and 4, the light guide plate 300 according to the present invention has a rectangular plate shape of a rectangular parallelepiped and has a first seating part 310 and a second seating part 320, which are stepped stepped portions, on the top. The storage groove 330 is formed on one side of the lower portion.

The first seating part 310 is formed on the light guide plate 300, and the first seating part 310 is formed from the first seating surface 310a having a flat and planar shape, and the first seating surface 310a. A second seating surface 320a that is bent upwardly, and the second seating portion 320 is bent to the outside of the first seating portion 310 at the first sidewall 310b. And a second sidewall 320b bent upward from the second seating surface 320a. That is, a plurality of optical sheets 510 are sequentially stored in the first seating surface 310a and the first sidewall 310b, and the second seating surface 320a and the second sidewall 320b are disposed in the liquid crystal display panel 100. Is seated.

An accommodating groove 330 is formed at a lower side of the light guide plate 300 in a shape of a long bar having a rectangular shape formed inward of the light guide plate 300. That is, the receiving groove 330 is formed long in a corresponding lower portion of the upper surface of the light guide plate 300, that is, the upper surface of the light guide plate 300 formed outside the second seating surface 320a. The LED element 210 of the light source unit 200 is accommodated. In this case, although one housing groove 330 is formed in the drawing, when the light source unit 200 is installed at both sides of the light guide plate 300, the storage groove 330 may be further formed at an opposite position of the housing groove 330. It may be.

In addition, as shown in FIG. 5, a lower seating part 340 may be further formed below the light guide plate 300. That is, the lower seating portion 340 includes a lower seating surface 340a and a lower sidewall 340b vertically bent from the lower seating surface 340a. In the lower seating portion 340, the reflective sheet 400 may be seated on the lower seating surface 340a and the lower sidewall 340b of the lower seating portion 340 to accommodate the light guide plate. By being stored below the 300, the overall thickness of the liquid crystal display may be reduced. In this case, the lower seating portion 340 is preferably formed to be large enough to cover the lower portion of the light guide plate 300. That is, by covering the lower part of the light guide plate 300 as much as possible, the reflective sheet 400 may reflect the light emitted to the lower part of the light guide plate 300 to the maximum, thereby increasing the brightness of the light.

Thus, as shown in FIG. 2, in the liquid crystal display, a reflector 400 is disposed under the light guide plate 300, and the back cover 230 of the light source unit 200 is part of the lower part of the reflector 400. It is formed to surround the lower and side portions of the light guide plate 300, including. In this case, the LED device 210 adhered to the back cover 230 is accommodated in the receiving groove 330 formed under the light guide plate 300. In addition, a plurality of optical sheets 500 are accommodated in the first seating portion 310 of the light guide plate 300, and a liquid crystal display panel 100 is second mounted on the plurality of optical sheets 500. It is seated on the part 320.

In addition, the light leakage preventing member 600 includes a portion of the liquid crystal display panel 100 to cover the upper and side portions of the light guide plate 300 in order to prevent the light leakage phenomenon in which the external light is emitted. Attached. In this case, as the light leakage preventing member 600, a black tape is used to prevent light from transmitting.

That is, when the light emitted from the light source unit 200 is incident on the light guide plate 300, the light leakage preventing member 600 blocks the light emitted to the outside of the display area of the liquid crystal display panel 100. In this case, the light leakage preventing member 700 may be further formed on the second seating surface 320a and the second sidewall 320b of the second seating part 320 of the light guide plate 300, which is formed from the light guide plate 300. It blocks the light incident to the side of the liquid crystal display panel 100.

As the light leakage preventing members 600 and 700, a reflective sheet may be attached in addition to the black tape. That is, by providing the reflective sheet on the upper and side portions of the light guide plate 300 and the second seating portion 320 on which the liquid crystal display panel 100 is mounted, the liquid crystal display panel may be formed from the light incident on the light guide plate 300. There is an effect that the light can be concentrated in the display area of the liquid crystal display panel 100 by reflecting the light of an area other than the display area of the inside.

Thus, the light leakage preventing members 600 and 700 may prevent light leakage that may occur in the liquid crystal display including the light guide plate 300 according to the present invention.

In the above, the accommodating groove 330 is formed under the light guide plate 300 to accommodate the light source unit 200. However, the accommodating groove 330 is removed and the light source unit 200 is provided on one side of the light guide plate 300. A liquid crystal display device may be configured, and the liquid crystal display device may be configured by forming the side portion of the light guide plate 300 to be inclined from the upper side to the inner side thereof so as to be combined with the back cover 230 of the light source unit 200.

In addition, in the above, although the light leakage preventing member 600 is illustrated in a rectangular frame shape, the light leakage preventing member 600 is not limited thereto.

Although described above with reference to the drawings and embodiments, those skilled in the art that the present invention can be variously modified and changed within the scope without departing from the spirit of the invention described in the claims below. I can understand.

As described above, the liquid crystal display of the present invention has proposed a structure in which the light guide plate and the mold frame are integrally formed. Therefore, the present invention has the effect of reducing the cost and quality at the same time by preventing the occurrence of a molding problem during the mold management and assembly of the mold frame and the light guide plate.

In addition, the present invention by removing the mold frame is configured, there is an effect that can simplify the assembly time and assembly.

In addition, the present invention is configured by removing the mold frame, there is an effect that can be made as thin as the thickness of the existing mold frame.

In addition, the present invention can be arranged in the receiving groove on the rear side of the light guide plate, there is an effect that can be achieved in assembly time and assembly simplification.

In addition, the present invention has the effect of reducing defects due to scratches, etc. that may occur in the assembly process by simplifying the assembly of the light source unit.

In addition, according to the present invention, even when the liquid crystal display panel is seated on the light guide plate and the light guide plate is bent, the liquid crystal display panel also flows in the same direction, so that external pressure is not applied to the liquid crystal display panel, thereby eliminating interference between components. There is.

In addition, the present invention has an effect of preventing the light leakage phenomenon of the liquid crystal display device by attaching the light leakage preventing member to the liquid crystal display device.

Claims (15)

In the light guide plate used for the liquid crystal display device, At least one seating portion formed in a stepped shape inward on the upper surface, Receiving groove formed in one side of the lower surface Light guide plate comprising a. The method of claim 1, wherein the seating portion is composed of a first seating portion and a second seating portion, the first seating portion includes a first seating surface and a first side wall bent vertically from the first seating surface, the second seating portion And a second seating surface vertically extending outwardly from the first sidewall and a second sidewall bent perpendicularly to the second seating surface. The light guide plate according to claim 1 or 2, further comprising a lower seating portion formed spaced apart from the accommodation groove on the lower surface. A light guide plate having at least one seating portion formed in a stepped shape inward on an upper surface thereof; A light source unit providing light to the light guide plate; At least one optical sheet housed in the seating part; Reflective sheet disposed under the light guide plate Backlight assembly comprising a. The backlight assembly of claim 4, further comprising an accommodation groove formed on one side of the lower surface of the light guide plate, wherein the light source is accommodated in the accommodation groove. The backlight assembly of claim 4 or 5, further comprising a lower seating portion formed inwardly of the lower surface of the light guide plate, wherein the lower seating portion accommodates a reflective sheet. The backlight assembly of claim 5, wherein the light source unit comprises an LED element, a substrate on which the LED element is mounted, and a back cover adhered to a lower portion of the substrate. The method of claim 7, wherein the back cover includes a cover base bonded to a substrate, and a cover side wall portion bent upward from the cover base, wherein the cover base and the cover side wall portion are formed to surround the lower side and the side wall of the light guide plate. Backlight assembly. A light guide plate having a first seating portion and a second seating portion formed in a step shape inwardly on an upper surface thereof; A light source unit providing light to the light guide plate; A reflection sheet provided below the light guide plate; An optical sheet seated on the first seating part; A liquid crystal display panel mounted on the second mounting portion Liquid crystal display comprising a. The liquid crystal display of claim 9, further comprising an accommodation groove formed on one side of the lower surface of the light guide plate, wherein the light source is accommodated in the accommodation groove. The liquid crystal display of claim 10, further comprising a lower seating part spaced apart from the accommodating groove, wherein the lower seating part accommodates a reflective sheet. The liquid crystal display of claim 9, further comprising a light leakage preventing member to block light emitted from the light guide plate. The liquid crystal display of claim 12, wherein the light leakage preventing member surrounds an upper portion and a side portion of the light guide plate. The liquid crystal display of claim 12, wherein the light leakage preventing member is formed in the second seating portion. The liquid crystal display device according to any one of claims 12 to 14, wherein the light leakage preventing member is a black tape or a reflective sheet.

Images