KR100947429B1 - LCD Display - Google Patents

Abstract

A liquid crystal display device according to an embodiment of the present invention, the liquid crystal display panel; A main flexible printed circuit board (FPCB) connected to the liquid crystal display panel and the pad unit, the light source device mounted thereon, and the first to fifth flexible printed circuit boards connected thereto; A light guide plate facing the light source element to receive light and providing the light to the liquid crystal display panel; And a bottom chassis disposed below the liquid crystal display panel and the light guide plate, the bottom chassis configured to accommodate the bottom light chassis, wherein the light source element is mounted on a fifth FPCB protruding from both edges of the second FPCB, and the fifth FPCB is bent to form a second chassis. It is characterized in that attached to one side.

Description

Liquid Crystal Display Device

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly, to a liquid crystal display device having an integrated flexible printed circuit board (FPCB) for transmitting an electrical signal to the liquid crystal display device and mounting a light source device (LED) of the backlight unit.

Recently, various flat panel displays have been developed to reduce weight and volume, which are disadvantages of cathode ray tubes. The flat panel display includes a liquid crystal display, a field emission display, a plasma display panel, and an organic light emitting display.

Here, the liquid crystal display has been attracting attention as an alternative means of overcoming the disadvantages of the conventional cathode ray tube because of the advantages of miniaturization, light weight, and low power, and is now a portable device such as a mobile phone and a portable digital assistor (PDA). In addition, it is also installed in the monitors and TVs, such as medium and large products, and most of the liquid crystal display devices are currently employed in the display unit of most portable devices such as mobile phones or PDAs.

However, in the conventional liquid crystal display device as a portable display device, in accordance with the trend of miniaturization and slimming of portable devices, the overall thickness of the liquid crystal display device is reduced, and protection elements, such as unnecessary driving elements, are eliminated. Slimming is requested.

The present invention provides a liquid crystal display device in which a mold frame and a flexible printed circuit board (FPCB) for a light source device (hereinafter referred to as FPCB) are removed in order to realize a slimmer body. The light source device is mounted on a main FPCB, and the light guide plate is aligned with the center of the light source device. And a liquid crystal display device for overcoming a decrease in luminance due to a decrease in light efficiency.

In order to achieve the above object, a liquid crystal display device according to an embodiment of the present invention, the liquid crystal display panel; A main flexible printed circuit board (FPCB) connected to the liquid crystal display panel and the pad unit and configured to mount a light source device and connect the first to fifth flexible printed circuit boards; A light guide plate facing the light source element to receive light and providing the light to the liquid crystal display panel; And a bottom chassis disposed below the liquid crystal display panel and the light guide plate, the bottom chassis configured to accommodate the bottom light chassis, wherein the light source element is mounted on a fifth FPCB protruding from both edges of the second FPCB, and the fifth FPCB is bent to form a second chassis. It is characterized in that attached to one side.

The main FPCB may include a first FPCB having a pad part connected to a pad part of the liquid crystal display panel and connected thereto; A second FPCB connected to the first FPCB in one section and mounted with a driving component to which an electrical signal is applied; A fourth FPCB having a pad portion connected to the driving PCB; A third FPCB connecting the second FPCB and the fourth FPCB; The light source device is mounted, and is connected to both edge portions of the second FPCB, and is bent and is composed of a fifth FPCB attached to one surface of the second FPCB by an adhesive tape.

At this time, the light source element is mounted on the first surface of the fifth FPCB, an adhesive tape is formed on the second surface of the fifth FPCB, and the fifth FPCB is bent and adhered to one surface of the second FPCB by the adhesive tape. .

In addition, the second FPCB is inserted into the bottom surface of the second substrate of the liquid crystal display panel so as to be in close contact with the second FPCB. Characterized by confrontation.

In addition, the light source element is positioned on the surface of the second FPCB, the adhesive tape, the fifth FPCB is sequentially stacked, the center height of the light source element coincides with the center height of the light guide plate, the center height of the light source element is It is characterized by being adjusted by the thickness.

According to the present invention, by eliminating the mold frame of the liquid crystal display and the flexible printed circuit board (hereinafter referred to as FPCB) for the light source device, the slimming and manufacturing cost reduction effects can be obtained, and the light source device is mounted on the main FPCB. In addition, by matching the center of the light guide plate and the light source element has the advantage that it is possible to overcome the brightness degradation due to light leakage and light efficiency degradation.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

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

1 is an exploded perspective view of a liquid crystal display according to an exemplary embodiment of the present invention. 2 is a cross-sectional view of the combination of the specific region (main FPCB coupling region) of FIG.

1 and 2, a liquid crystal display according to an exemplary embodiment of the present invention includes a liquid crystal display panel 200, a backlight unit 300, a driving printed circuit board (PCB) 500, and a main flexible printed circuit. It comprises a substrate (FPCB) (100).

The liquid crystal display panel 200 includes a first substrate 210, a second substrate 220, and a liquid crystal (not shown) injected therebetween.

The second substrate 220 includes a plurality of thin film transistors (“TFTs”) arranged in a matrix form, and an integrated circuit 230 is mounted on one side of the second substrate 220. The data signal and the scan signal are supplied from the integrated circuit 230. In addition, a pad part 240 is provided on the lower end of the integrated circuit in the second substrate to receive a signal.

The first substrate 210 is disposed to face the second substrate 220. A common electrode made of a transparent electrode is formed on the front surface of the first substrate 111a, and a predetermined voltage is applied to the common electrode. Accordingly, a predetermined electric field is formed between the common electrode and the pixel electrode formed on the second substrate, and the arrangement of the liquid crystal injected between the first substrate 210 and the second substrate 220 by such an electric field. The angle is changed, and the light transmittance is changed according to the changed arrangement angle to display a desired image. In general, polarizers (not shown) are further provided on the outer surfaces of the first substrate 210 and the second substrate 220.

The backlight unit 300 irradiates light from the lower part of the panel to display an image, and includes a light source element 310, a light guide plate 320, an optical sheet 350, a rim frame 360, and the like. .

In the embodiment of the present invention, the light source elements 310 are mounted on the main FPCB 100 and provided to the backlight unit, and generate light having a predetermined luminance in response to a driving signal transmitted to the main FPCB 100.

That is, in the embodiment of the present invention, the main FPCB 100 may be configured by mounting the light source elements 310 and connecting the first to fifth flexible circuit boards 110 to 150.

The main flexible printed circuit board (FPCB) 100 mounts various circuit elements 370 or is connected to another printed circuit board 500, and the like, and a first pad part 112 is formed on the liquid crystal display panel. By being connected to the pad unit 240, a control signal and / or power are supplied to the integrated circuit 230 of the liquid crystal display panel. In other words, the main FPCB 100 transmits an electrical signal of the driving printed circuit board 500 to the backlight unit 300 and the liquid crystal display panel 200. That is, the flexible printed circuit board 100 transmits an electrical signal transmitted to the printed circuit board 500 from the outside to the liquid crystal display panel 200, and transfers the components on the flexible printed circuit board 100 that receive the electrical signal. The backlight unit 300 is provided. In addition, in the embodiment of the present invention, the light source device (LED) 310 is further mounted on the main FPCB 100.

By mounting the light source element 310 on the main FPCB 100 as described above, the FPCB for the light source element, which is provided separately from the main FPCB 100 in the conventional liquid crystal display device, can be removed. Slimming and manufacturing cost savings will be achieved.

That is, in the embodiment of the present invention, in the light source element 310 is mounted on the main FPCB 100, the light source element is protruded from both corners of the second FPCB 120 to the fifth FPCB 150 connected. The fifth FPCB 150 is bent and attached to one surface of the second FPCB 120.

As shown in FIG. 2, in the main FPCB 100, the pad part 112 of the first FPCB 110 is connected to the pad part 240 formed on one side of the liquid crystal display panel 200. The second FPCB 120 is bent and inserted into the bottom surface of the second substrate 220 of the panel, and the fifth FPCB 150 is bent at the end of the second FPCB 120 to form the second FPCB 120 by an adhesive tape. Is attached to. At this time, since the light source element 310 is mounted on the fifth FPCB 150, the light source element faces the light guide plate 320 to be described later by the bending insertion of the main FPCB 100.

That is, the light source element 310 is located on a surface on which the second FPCB 120, the adhesive tape 152, and the fifth FPCB 150 are sequentially stacked, which will be more clearly understood through the cross-sectional view shown in FIG. 2. Can be.

At this time, the height in which the light source element 310 is mounted may be adjusted by the thickness of the adhesive tape 152, and thus adjusting the thickness of the light source element 310 is the light guide plate 320 and the light source element 310. In order to match the center of the () to overcome the brightness degradation due to light leakage and light efficiency degradation.

In addition, the fourth FPCB 140 of the main FPCB is connected through the third FPCB 130 connected to both sides of the second FPCB 120, the pad portion 142 formed in the fourth FPCB 140 is a driving PCB 500 ), And transmits an electrical signal of the driving printed circuit board 500 to the backlight unit 300 and the liquid crystal display panel 200.

A detailed shape of the main FPCB will be described below in more detail with reference to FIGS. 3 and 4.

The light guide plate 320 supplies the light supplied from the light source elements 310 to the liquid crystal display panel 200. That is, the light guide plate 340 supplies the light supplied from the light source located at its side to the liquid crystal display panel 200 located at the top thereof.

At this time, in order to overcome the lowering of the brightness of the liquid crystal display device, light emitted from the light source element 310 and incident on the light guide plate 320 must be prevented from leaking (light leakage) or deterioration in efficiency. And the center of light guide plate should be aligned.

To this end, in the embodiment of the present invention, the light source device 310 is mounted on the main FPCB 100, and the second FPCB 120, the adhesive tape 152, and the fifth FPCB 150 are sequentially stacked. The height at which the light source element 310 is mounted is adjusted by the thickness of the adhesive tape 152 to match the center of the light guide plate 320 and the light source element 310 to reduce luminance due to light leakage and light efficiency. It is characterized by being capable of overcoming the degradation.

In addition, the reflective sheet (not shown) is disposed on the rear surface of the light guide plate 340 to supply the light leaked from the light guide plate 340 to the light guide plate 340. That is, the reflective sheet improves light efficiency by re-supplying the light incident on the light guide plate 340, and the optical sheets 350 improve the brightness of the light supplied from the light guide plate 340 to improve the light efficiency. 200).

The driving printed circuit board 500 applies signals to the display panel and the backlight unit through the main flexible printed circuit board 100 in response to control signals supplied from the outside.

Meanwhile, the bottom chassis 400 between the driving printed circuit board 500 and the backlight unit is a support for supporting the display panel.

The bottom chassis 400 is formed of a metal having high strength, and is positioned below the reflector to accommodate the liquid crystal display panel 104 and the backlight assembly 150.

In this case, the mold frame may be removed by stably storing the optical sheets 350, the light guide plate 320, and the reflecting plate (not shown) in an inner space formed of a bottom surface and sidewalls of the bottom chassis 400.

According to the above-described liquid crystal display device according to the present embodiment, it is possible to provide a slimmer liquid crystal display device by removing the mold frame while reducing the manufacturing cost of the liquid crystal display device. In addition, since the backlight assembly 300 is inserted into the bottom chassis 400 formed of metal having high strength, the liquid crystal display having improved rigidity may be provided.

3 is a perspective view illustrating a main FPCB shown in FIG. 1, and FIGS. 4A and 4B are front views of the main FPCB shown in FIG. 1, and FIG. 4A shows a shape in which the fifth FPCB is unfolded, and FIG. 5FPCB shows the folded shape.

3 and 4, the main FPCB 100 is integrally connected to the first FPCB 110, the second FPCB 120, the third FPCB 130, the fourth FPCB 140, and the fifth FPCB 150. Is done.

First, the first FPCB 110 includes a pad part 112 connected to the pad part 240 of the liquid crystal display panel, and is connected to the pad part 240 of the liquid crystal display panel as shown in FIG. 2.

At this time, the first FPCB 110 is connected to one section of the second FPCB 120, and in particular, the base part connected to the second FPCB 120 is bent much during mounting, so that the internal conductive wiring layer is composed of one layer. Preferably, in this case, the thickness of the first FPCB 110 is formed thinner than the thicknesses of the second FPCB 120 and the third FPCB 130.

The second FPCB 120 is connected to the first FPCB 110 in one section and is connected to the third FPCB 130 in the other section. In the drawing, the first FPCB 110 is connected to the center of the second FPCB 120, and the third FPCB 130 is connected at both sides 130a and 130b of one end of the second FPCB 120. At this time, the first FPCB 110 and the third FPCB 130 are connected to the second FPCB 120 in the same direction, and the width W1 of the first FPCB 110 is larger than the width W2 of the third FPCB, The length L1 of the first FPCB 110 is shorter than the length L2 of the third FPCB.

The component is mounted on the second FPCB 120. That is, the second FPCB 120 mounts the driving component 370 to which an electrical signal is applied. The driving component is not limited, but may include a light emitting diode, a boosting circuit, and the like.

The third FPCB 130 connects the second FPCB 120 and the fourth FPCB 140 and is a curved section. Like the first FPCB 110, the third FPCB 130 preferably has a single conductive wiring layer formed therein, and in this case, the first FPCB 130 110 is formed thinner than the 2nd FPCB 120 and the 4FPCB 140 which are not bent.

The fourth FPCB 140 includes a pad unit 142 connected to the driving PCB 500, and receives a predetermined signal from the driving PCB.

In addition, the fifth FPCB 150 is bent at the end of the second FPCB 120 and attached to the second FPCB 120 by an adhesive tape 152. At this time, since the light source element 310 is mounted on the fifth FPCB 150, the light source element faces the light guide plate 320 as shown in FIG. 2 by the bending insertion of the main FPCB 100. Done.

That is, the light source element 310 is located on a surface on which the second FPCB 120, the adhesive tape 152, and the fifth FPCB 150 are sequentially stacked, which will be more clearly understood through the cross-sectional view shown in FIG. 2. Can be.

In this case, the height at which the light source element 310 is mounted may be adjusted by the thickness of the adhesive tape 152, and thus adjusting the thickness of the light source element 310 may include the light guide plate 320 and the light source element ( This is to match the center of 310 so as to overcome the decrease in luminance due to light leakage and light efficiency degradation.

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

FIG. 2 is a cross sectional view of a specific region (main FPCB bonding region) of FIG. 1; FIG.

3 is a perspective view showing the main FPCB shown in FIG.

4A and 4B show a front view of the main FPCB shown in FIG.

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

100: main FPCB 110: first FPCB

120: second FPCB 130: third FPCB

140: fourth FPCB 150: fifth FPCB

152: adhesive tape

Claims (6)

A liquid crystal display panel; A main flexible printed circuit board (FPCB) connected to the liquid crystal display panel and the pad unit, the light source device mounted thereon, and the first to fifth flexible printed circuit boards connected thereto; A light guide plate facing the light source element to receive light and providing the light to the liquid crystal display panel; A bottom chassis disposed under the liquid crystal display panel and the light guide plate to receive the liquid crystal display panel; The light source element is mounted on a fifth FPCB protruding from both corners of the second FPCB, the fifth FPCB is bent and attached to one surface of the second FPCB, The main FPCB, A first FPCB having a pad part connected to the pad part of the liquid crystal display panel and connected thereto; A second FPCB connected to the first FPCB in one section and mounted with a driving component to which an electrical signal is applied; A fourth FPCB having a pad portion connected to the driving PCB; A third FPCB connecting the second FPCB and the fourth FPCB; And a fifth FPCB mounted on the light source device, connected to both edge portions of the second FPCB, and bent to be attached to one surface of the second FPCB by an adhesive tape. delete The method of claim 1, The light source device is mounted on the first surface of the fifth FPCB, an adhesive tape is formed on the second surface of the fifth FPCB, and the fifth FPCB is bent onto one surface of the second FPCB by the adhesive tape and adhered to the liquid crystal. Display. The method of claim 1, The second FPCB is bent and inserted into the bottom surface of the second substrate of the liquid crystal display panel, and the fifth FPCB is bent at the end of the second FPCB and attached to the second FPCB by an adhesive tape so that the light source element faces the light guide plate. A liquid crystal display device. The method of claim 4, wherein And the light source element is positioned on a surface of the second FPCB, the adhesive tape, and the fifth FPCB sequentially stacked so that the center height of the light source element coincides with the center height of the light guide plate. The method of claim 5, And a center height of the light source element is controlled by a thickness of the adhesive tape.

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