KR20130058478A - Backlight unit and lcd module inculding the same - Google Patents

Abstract

PURPOSE: A backlight unit and an LCD(Liquid Crystal Display) device module including the same are provided to enable a part of an LED array to protrude toward an optical sheet and to support the optical sheet, thereby eliminating a protrusion part formed at the optical sheet and a guide panel. CONSTITUTION: An LED FPCB(Flexible Printed Circuit Board) includes a supporting part(219) protruding with a fixed length at both ends. The supporting part touches the edge part of an optical sheet(230). As a part of uneven portions of the optical sheet is removed, the optical sheet becomes flat. Remaining uneven portions(135e,135f) are distant from an LED array(210). Therefore, when the light passing through the optical sheet is reflected from a bent portion, brightness to generate light bounce is not generated.

Description

BACKLIGHT UNIT AND LCD MODULE INCULDING THE SAME}

The present invention relates to a backlight unit, and more particularly, to include a backlight unit that improves image quality by improving light attenuation caused by a coupling structure of an LED array and an optical sheet constituting the backlight unit in a photometric liquid crystal display device. The present invention relates to a liquid crystal display module.

The liquid crystal display device uses a passive transmission display device, and the gray level of a desired image is displayed on the screen by adjusting the amount of light passing through the liquid crystal layer by the refractive index anisotropy of the liquid crystal molecules. Accordingly, a liquid crystal display device includes a backlight unit that provides light to the liquid crystal layer for displaying an image, and is coupled and modularized by various mechanism structures.

In the above-described liquid crystal display, the backlight unit is generally classified into two types according to the structure of the light source.

One is the direct type LED PKG, which is a light source located on the back of the liquid crystal panel, and emits light directly to the front of the panel from the bottom. The other is the edge type, and the LED PKG is Located in the side of the liquid crystal panel is a method of providing the light by switching the direction of the panel through the optical sheet or the like.

The above-described direct type method is mainly applied to manufacturing a liquid crystal panel for a large screen TV because the light emitted from the LED PKG is directly supplied to the liquid crystal panel, and not only can be applied to a large area panel but also has high brightness.

On the other hand, the metering type system is installed on the side of the liquid crystal panel to supply light to the liquid crystal panel through the optical sheet, the reflector plate and the light guide plate. Therefore, it is difficult to apply to a large area liquid crystal panel as compared to the direct type type system. Since light is supplied, it is difficult to obtain high brightness. However, there is an advantage that the thickness of the liquid crystal display module can be made thin because the backlight unit is located at the side.

1 is an exploded perspective view showing a part of a conventional photometric liquid crystal display module.

As shown, the conventional photometric type liquid crystal display module 1 includes a LED array 20 and LED array 20 in which a plurality of LED PKGs are arranged in a line and provided on at least one side of the liquid crystal display. A plurality of optical sheets 35 disposed on side surfaces of the optical sheet 35, a guide panel 40 on which the optical sheets are mounted, and an optical sheet 35 and an upper portion of the optical sheets 35 mounted on one side thereof. The light shielding tape 50 is fixed to the liquid crystal panel (not shown).

In the liquid crystal display module 1 having such a structure, the plurality of optical sheets 35 optically converts light incident from the lower light guide plate (not shown) to provide the upper liquid crystal panel to stably maintain the flow of the module. It must be fixed and aligned with each other. Accordingly, a predetermined recess is formed in a portion of the guide panel 40 that contacts the optical sheet 35 in the inward direction, and a portion of the side surface of the optical sheet 35 protrudes corresponding to the recess. ) Is formed and combined to maintain alignment between the optical sheets 35 and to be stably fixed.

FIG. 2A is a plan view showing a part of the assembled liquid crystal display module, and FIG. 2B is an enlarged view of a portion 'A' of FIG. 2A. As illustrated, the guide panel 40 has an LED array 20 on one side. ) Is seated, and the optical sheet 35 is mounted inside to surround each side. In this structure, the LED array 20 is spaced apart from the optical sheet 35 by a predetermined distance, and although not shown, the light emitting surface of the LED PKG (not shown) bonded to the rear surface of the LED array 20 is formed of the optical sheet 35. It is disposed to face one side of the light guide plate (not shown) provided on the back.

In addition, the optical sheet 35 is bordered by the guide panel 40 except for the side adjacent to the LED array 20, a plurality of convex portions (35a to 35d) protruding on both sides facing each other. . In addition, the guide panel 40 has a recessed portion formed on an inner side thereof, thereby stably fixing the optical sheet in a form in which the convex portions 35a to 35d are inserted.

However, the liquid crystal display module having such a structure causes light rays to be generated by recesses and recesses of the optical sheet and the guide panel. Looking at part A of the drawing, when the light emitted from the LED array 20 passes through the light guide plate (not shown) inside the optical sheet, the incident light L1 is a bent portion of the convex portion 35a and the recessed portion 40a. Is reflected (L2), the light (L2) is scattered so that the luminance of the corresponding region in the image is different from the other region.

The above-mentioned light scattering phenomenon occurs especially in recesses and convex portions of the region adjacent to the light source, which causes deterioration of the image quality.

The present invention has been made to solve the above-described problems, the backlight unit and the liquid crystal display including the same to remove the at least one uneven portion formed in the optical sheet and the guide panel in the light metering backlight unit to improve the light phenomena The purpose is to provide.

In order to achieve the above object, a backlight unit according to a preferred embodiment of the present invention, the light guide plate for guiding light incident on at least one side to the upper surface; At least one optical sheet disposed on an upper surface of the light guide plate to diffuse and condense incident light and output the light to the upper surface; A reflector disposed on a lower surface of the light guide plate; And an LED array including a LED FPCB bonded to a plurality of LEDs PKG, spaced apart from the optical sheet, and having a support portion contacting at least one side of the optical sheet.

The support portion is characterized in that the form extending in the direction of the optical sheet at both ends of the FPCB.

The optical sheet is characterized in that the side is flat in the region adjacent to the LED array.

The support portion is characterized in that the thickness is the same as the optical sheet.

In order to achieve the above object, a liquid crystal display module including a backlight unit according to a preferred embodiment of the present invention, a liquid crystal panel; A backlight unit providing light to the liquid crystal panel; A guide panel for mounting the liquid crystal panel and the backlight unit, the backlight unit comprising: a light guide plate for guiding light incident on at least one side surface to the liquid crystal panel; At least one optical sheet disposed on an upper surface of the light guide plate to diffuse and condense incident light and output the light to the upper surface; A reflector disposed on a lower surface of the light guide plate; And an LED array including a plurality of LED PKGs bonded to each other, spaced apart from the optical sheet, and an LED FPCB having a support portion which is in contact with at least one side of the optical sheet.

The support portion is characterized in that the form extending in the direction of the optical sheet at both ends of the FPCB.

The optical sheet is characterized in that the side is flat in the region adjacent to the LED array.

The optical sheet is characterized in that at least one iron portion for supporting and fixing is formed on the side.

The guide panel is characterized in that at least one recess corresponding to the convex portion is formed.

The FPCB is attached to the liquid crystal panel together with the guide panel by shading tape.

The backlight unit and the liquid crystal display device module according to the embodiment of the present invention support the optical sheet by protruding a portion of the LED array in the optical sheet direction, thereby eliminating the uneven portions formed in the optical sheet and the guide panel, thereby causing light leakage. By improving the quality of the image can be achieved.

1 is an exploded perspective view showing a part of a conventional photometric liquid crystal display module.
2A is a plan view of a part of the assembled LCD module, and FIG. 2B is an enlarged view of part 'A' of FIG. 2A.
3 is an exploded perspective view illustrating a structure of a liquid crystal display module including a backlight unit according to an exemplary embodiment of the present invention.
4A is a plan view of a backlight unit according to an exemplary embodiment of the present invention, and FIG. 4B is an enlarged view of the LED array included in the backlight unit.
5A and 5B illustrate a cross-sectional part of a liquid crystal display module according to an exemplary embodiment of the present invention.

Hereinafter, a backlight unit and a liquid crystal display device module including the same according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

3 is an exploded perspective view illustrating a structure of a liquid crystal display module including a backlight unit according to an exemplary embodiment of the present invention.

As illustrated, the liquid crystal display device module including the backlight unit of the present invention includes a liquid crystal panel 100 for displaying an image, a backlight unit 200 for providing light thereto, and a guide panel 300 for modularizing the liquid crystal panel 100. Is done.

The liquid crystal panel 100 includes a liquid crystal layer in which the first substrate and the second substrate are bonded to each other by a predetermined distance and interposed therebetween. In addition, the first substrate is provided with a driver IC 150 to implement an image as a control and an image signal is applied.

On the first substrate constituting the liquid crystal panel 100, a thin film transistor as a switching element, various wirings, and pixel electrodes are formed. The second substrate is a color filter substrate for displaying RGB colors, and a color filter layer and a black matrix BM are formed. The driver IC 150 may include a gate driver for providing a scan signal for driving the above-described thin film transistor, and a data driver for providing a data signal to the pixel electrode, and may be connected to an external system through a flexible cable (not shown). And a power supply unit.

The liquid crystal panel 100 described above will be described in detail. A plurality of scan and data lines are formed on the first substrate to define a plurality of pixel regions, and a thin film transistor is formed in each pixel region. Formed. In addition, the thin film transistor includes a gate electrode connected to a gate line, a semiconductor layer formed by stacking amorphous silicon, etc. on the gate electrode, a source electrode and a drain electrode formed on the semiconductor layer and electrically connected to the data wiring and the pixel electrode. It serves as a switching element.

The second substrate is a color filter composed of a plurality of sub-color filters that realize red, green, and blue colors, and a black that separates each sub-color filter and blocks light passing through the liquid crystal layer. It consists of a matrix BM.

The first and second substrates face each other by sealants formed on the outer side of the image display area and are bonded to each other at a predetermined distance to constitute the liquid crystal panel 100. In addition, polarizing plates that linearly polarize incident and output light are attached to outer surfaces of the bonded first and second substrates.

The backlight unit 200 includes an LED array 210, a light guide plate 220, an optical sheet 230, and a reflector plate 240.

The LED array 210 may include LED PKG 211, which is a plurality of light sources disposed on one side of the liquid crystal panel 100 and emitting light, and an LED FPCB in which the LED PKG 211 is bonded in a line. 215).

Here, the LED PKG 211 which is a light source may be an R, G, B LED device that emits monochromatic light of R (Red), G (Green), or B (Blue), or a WLED device in which one device emits white light. Can be.

When the LED PKG emitting monochromatic light is disposed, the monochromatic LED PKGs of R, G, and B are alternately arranged at regular intervals, and the monochromatic light emitted from the white light is mixed with white light and then provided to the liquid crystal panel 100. When the LED PKG emitting white light is arranged, a plurality of LED PKGs are arranged at a predetermined interval to provide white light to the liquid crystal panel 100.

In addition, the LED PKG 211 constituting the LED array 210 is bonded to the LED FPCB 215 of a flexible material. The LED FPCB 215 electrically connects the plurality of LED PKGs 211 through electrodes formed on one surface, and each electrode is connected to the liquid crystal display module through a connection part 217 extending from one side of the LED FPCB 215. It is electrically connected to an external power source and the like provided on the back side of the.

In addition, at least one support part 219 is formed at two corners of the other side of the LED FPCB 215, that is, the inner side of the liquid crystal display. The support part 219 extends so that the edge of the LED FPCB 215 has a predetermined width so that the bottom surface is in contact with the upper part of the light guide plate 220, which will be described later, and the optical sheet 230 disposed above the light guide plate 220. It is partly in contact with the side.

According to this structure, the support part 219 supports one surface of the plurality of optical sheets 230, so that the alignment between the plurality of optical sheets 230 when the optical sheet 230 is expanded by the flow or heat of the liquid crystal display module. This prevents any misalignment or deviation.

In addition, the LED array 210 is disposed such that the light emitting surface of the LED PKG 211 faces at least one side of the light guide plate 220 along one side of the light guide plate 220. Accordingly, the light emitted from the LED array 210 is incident to the side of the light guide plate 220.

The light guide plate 220 is disposed to correspond to the lower portion of the liquid crystal panel 100 to guide the light emitted from the LED array 210 in the direction of the liquid crystal panel 100 without possible loss. The light incident on the light guide plate 220 is repeatedly refracted and reflected by the diffusing agent added to the inside of the light guide plate 220, and then exits to the other side of the light guide plate 220.

The optical sheet 230 includes a diffusion sheet for diffusing the light emitted from the light guide plate 220 and a plurality of light condensing light diffused by the diffusion sheet so that uniform light is supplied to all regions of the liquid crystal panel 100. It consists of a prism sheet.

Here, the diffusion sheet is typically provided with one sheet, but the prism sheet includes a first prism sheet and a second prism sheet in which the prism crosses vertically in the x and y axis directions to refract light in the x and y axis directions to provide light. It is configured to improve the straightness.

These optical sheets 230 should be aligned so that each side coincides without misalignment. Accordingly, one side may be supported by the support 219 of the LED array 210 as described above, and at least one of the other sides may have the same convex portion as that of the conventional optical sheet (35 in FIG. 2A). In addition, when the convex portion is formed in the optical sheet 230, the concave portion is formed in the guide panel described later.

In addition, a reflective sheet 240 is disposed on the rear surface of the light guide plate 220 to reflect the light emitted downward, and to proceed toward the upper direction of the light guide plate 220, that is, the liquid crystal panel 300. It is attached to the lower portion of the panel 300 to increase the light efficiency and to support the back of the liquid crystal display module.

The guide panel 300 has a rectangular frame shape, and on one side thereof, a plurality of protrusions on which the LED array 210 is mounted is formed, and the liquid crystal panel 100 is attached to the inside of the guide panel 300 by the light shielding tape 250. The light guide plate 220 and the plurality of optical sheets 230 are mounted in a stacked form. A reflective sheet 240 is attached to the bottom. The guide panel 300 may be made of a synthetic resin formed by a double injection molding (Injection molding) method.

Here, the light shielding tape 250 may serve to attach and fix the liquid crystal panel 100 and the guide panel 300, as well as block the light emitted from the optical sheet 230 from leaking to the outside. do. The light shielding tape 250 extends inwardly from an edge portion of the guide panel 300 to cover a part of the optical sheet 230.

According to this structure, the liquid crystal display device module including the backlight unit of the present invention removes a portion adjacent to the light source among the uneven portions formed in the optical sheet and the guide panel, and supports the optical sheet through the support of the LED array. By doing so, the light phenomenon can be improved.

Hereinafter, the coupling structure of the backlight unit and the mechanism structure of the present invention will be described with reference to the drawings.

4A is a plan view of a backlight unit according to an exemplary embodiment of the present invention, and FIG. 4B is an enlarged view of the LED array included in the backlight unit.

As shown, the backlight unit of the present invention includes a stacked optical sheet 135, and the LED array 210 for supporting one side of the optical sheet 135, the backlight unit is attached to the guide panel 300 It is bordered by.

In this structure, the LED array 210 is spaced apart from the optical sheet 135 by a predetermined distance, and protrudes in the direction of the optical sheet 135 from both sides to contact some edges of the optical sheet, and although not shown, the LED array 210 LED PKG (not shown) is bonded to the rear surface and is disposed to face one side of the light guide plate (not shown) provided as the rear surface of the optical sheet 135.

The LED array 210 is composed of a plurality of LED PKG (not shown) and a flexible LED FPCB 215 bonded to the LED PKG to the rear if not shown, the LED FPCB 215 is formed on the electrodes A plurality of LEDs PKG 211 are electrically connected to each other, and each electrode is electrically connected to an external power source and a driver (not shown) through a connection part 217 extending from one side of the LED FPCB 215. Typically, the external power source is disposed on the rear surface of the liquid crystal display device module, and the central region 216 of the connection unit 217 may be made of a material that can be flexed more flexibly.

In particular, the LED FPCB 215 is formed at both ends of the support portion 219 protruding to a predetermined length, the support portion 219 is extended by a distance corresponding to the distance between the LED FPCB 215 and the optical sheet 135. Abutting the edge portion of the optical sheet 135 (B). The support 219 may be formed to have the same thickness as the optical sheet 135.

In addition, the optical sheet 135 is bordered by the guide panel 400 except for the side facing the LED array 210, the convex portion provided on each side in contrast to the conventional structure (35a to 35d of Figure 2 Some of the) are removed to form a flat shape. The flat regions 135a and 135b from which the convex portions are removed are portions adjacent to the LED array 210.

The remaining portions of the convex portions 135e and 135f are areas that are far from the LED array 210, and fix the remaining side surface in addition to the surface supported by the LED array 210 in the optical sheet 135. Since the convex portions 135e and 135f are far from the light source, even when the light traveling inside the optical sheet 135 is reflected at the bent portion, the convex portions 135e and 135f do not have a luminance enough to generate light. It can realize the missing image.

Hereinafter, the coupling structure of the LED array and the optical sheet will be described with reference to the cross section of the liquid crystal display module of the present invention with reference to the drawings.

5A and 5B illustrate a cross-sectional part of a liquid crystal display module according to an exemplary embodiment of the present invention.

As shown, the liquid crystal display device module of the present invention includes a liquid crystal panel 100, a backlight unit 200 disposed on a rear surface of the liquid crystal panel, and a guide panel 300 mounted thereon.

In the liquid crystal panel 100, the first and second substrates on which various switching elements and wirings are formed face each other and are bonded to each other by a predetermined distance, and the liquid crystal layer is interposed between the two substrates. In addition, polarizing plates (not shown) for linearly polarizing light incident and output are attached to the outer surfaces of the bonded first and second substrates. In the liquid crystal panel 100 having such a structure, the optical characteristics of the liquid crystal layer are converted according to the electric field control between the two substrates to display the gray level of the image.

The backlight unit 200 is provided as a rear surface of the liquid crystal panel 100, and the LED array 210 is disposed on at least one side thereof, and the light guide plate 220 and the optical sheet 230 are parallel to the liquid crystal panel 100. It is disposed so as to correspond to the image display area of the light.

In particular, the LED array 210 is bonded to one surface of the FPCB 215 side by side in a plurality of LED PKG 211, is mounted on the guide panel 300 so that the bonding surface of the LED PKG 211 faces the bottom. . The connection part 217 extending from the FPCB 215 exits to the outside of the LCD module.

In addition, the side of the LED array 210 is provided under the liquid crystal panel 100 is provided with an optical member for guiding, diffusing and condensing the light emitted from the above-described LED PKG 211. The optical member diffuses light guided by the light guide plate 220 interposed between the light guide plate 220 and the liquid crystal panel 100 and the light guide plate 220 to supply incident light over the entire area of the liquid crystal panel 100. And a reflecting plate 240 disposed at a rear surface of the light guide plate 220 to collect light, and reflecting light emitted in a downward direction to the light guide plate 220.

The liquid crystal panel 100 and the backlight unit 200 described above are mounted on the guide panel 300 which is an opaque synthetic resin mechanism structure having a rectangular frame shape. The liquid crystal panel 100 is mounted on the upper surface in the inner direction of the guide panel 300, and the backlight unit 200 is mounted in the inner space, and the reflecting plate of the backlight unit 200 is disposed on the rear surface of the guide panel 300. 240 is attached.

In addition, the liquid crystal panel 100 is attached to the guide panel 300 by the light shielding tape 250, which is attached to the surface where the LED PKG 211 of the FPCB 215 is not bonded. The array 210 is fixed.

In the liquid crystal display module having the structure, the FPCBs 215 of the LED array 210 are disposed to face the optical sheet 230 so as to form a space 280 of a predetermined distance, at both ends of the FPCBs 215. At least one support part 219 is formed to extend to abut the edge portion of the optical sheet 230 made of a plurality of sheets (C).

According to the above structure, when the internal temperature of the liquid crystal display module increases, the optical sheet 230 expands in the direction of the LED array 210, but the support portion 219 holds both edges of the optical sheet 230. The expansion is suppressed. In addition, the alignment between the plurality of optical sheets 230 is maintained continuously.

Therefore, the backlight unit of the present invention and the liquid crystal display module including the same form a support part for supporting and fixing the optical sheet in the LED array, thereby improving the light phenomenon by removing the uneven parts formed on each side of the conventional optical sheet.

Many details are set forth in the foregoing description but should be construed as illustrative of preferred embodiments rather than to limit the scope of the invention. Therefore, the invention should not be construed as limited to the embodiments described, but should be determined by equivalents to the appended claims and the claims.

100: liquid crystal panel 150: driver IC
200: backlight unit 210: LED array
211: LED PKG 215: LED FPCB
217: connection portion 219: support portion
220: light guide plate 230: optical sheet
250: shading tape 300: guide panel

Claims (10)

A light guide plate for guiding light incident on at least one side surface to an upper surface;
At least one optical sheet disposed on an upper surface of the light guide plate to diffuse and condense incident light and output the light to the upper surface;
A reflector disposed on a lower surface of the light guide plate; And
A plurality of LED PKG is bonded, the LED array including an LED FPCB disposed to be spaced apart from the optical sheet, the support is formed in contact with at least one side of the optical sheet.
Backlight unit consisting of. The method of claim 1,
The support unit is a backlight unit, characterized in that extending in the direction of the optical sheet at both ends of the FPCB. The method of claim 1,
The optical sheet is a backlight unit, characterized in that the side is flat in the region adjacent to the LED array. The method of claim 1,
The support unit is a backlight unit, characterized in that the thickness is the same as the optical sheet. A liquid crystal panel;
A backlight unit providing light to the liquid crystal panel;
A guide panel for mounting the liquid crystal panel and the backlight unit;
The backlight unit may include a light guide plate configured to guide light incident on at least one side surface to the liquid crystal panel;
At least one optical sheet disposed on an upper surface of the light guide plate to diffuse and condense incident light and output the light to the upper surface;
A reflector disposed on a lower surface of the light guide plate; And
A plurality of LED PKG is bonded, the LED array including an LED FPCB disposed to be spaced apart from the optical sheet, the support is formed in contact with at least one side of the optical sheet.
Liquid crystal display module comprising a. The method of claim 5, wherein
The support unit is a liquid crystal display module, characterized in that extending in the direction of the optical sheet at both ends of the FPCB. The method of claim 5, wherein
The optical sheet is a liquid crystal display module, characterized in that the side surface is flat in the region adjacent to the LED array. The method of claim 7, wherein
The optical sheet has a liquid crystal display module, characterized in that at least one convex portion for supporting and fixing is formed on the side. The method of claim 8,
And at least one recess corresponding to the convex portion is formed in the guide panel. The method of claim 5, wherein
And the FPCB is attached to the liquid crystal panel together with the guide panel by shading tape.

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