KR102420788B1 - display device - Google Patents

Abstract

According to the present invention, the metal wiring exposed area between the bending part and the body part, which is vulnerable to the effects of electromagnetic interference (EMI) and radiofrequency interference (RFI) because a plurality of metal wires are densely formed, is formed of a mesh pattern. By protecting with the noise blocking unit, it is possible to effectively prevent signal distortion due to the influence of electromagnetic interference and radio frequency interference.
In addition, even if the mesh pattern is formed only on the first surface, it is possible to sufficiently prevent signal distortion due to electromagnetic interference and radio frequency interference, thereby reducing material cost and realizing a thin flexible printed circuit.
Furthermore, a reinforcing pattern is formed in the boundary region between the mesh pattern and the bending portion, and due to the high rigidity of the mesh pattern, cracks occurring in the boundary region between the mesh pattern and the bending portion during bending can be prevented.

Description

display device

The present invention relates to a display device, and more particularly, to a display device including a flexible printed circuit capable of preventing cracks due to bending while improving noise shielding effect.

In general, display devices such as Liquid Crystal Display (LCD), Plasma Display Panel (PDP), and Organic Light Emitting Diode (OLED) are easy to implement with high resolution and have a large screen. As a display device, it has various advantages.

Such a display device includes a display panel that includes a plurality of pixels and displays an image, and a driver that applies a signal to each pixel of the display panel.

In this case, the driving unit includes a printed circuit board (PCB), and is connected to one side of the display panel through a flexible printed circuit (FPC).

As such, the FPC includes a bonding part connected to the display panel, a bending part for bending, a body part including wires and electric devices arranged in various shapes, and a connector part for connecting to an external system.

In addition, in the step of modularizing the display device, the flexible printed circuit is bent and folded to the rear surface of the display device for miniaturization of the display device.

1 and 2 are perspective views schematically illustrating a conventional display panel and a flexible printed circuit.

As shown, a flexible cable such as a flexible printed circuit (FPC) 17 that outputs various signal voltages for driving the display panel 10 is connected along at least one edge of the display panel 10 for modularization. In the process, the display panel 10 is properly bent to the rear surface to be closely adhered.

Since the bonding portion and the bending portion of the FPC 17 are composed of a polyimide base film and a metal wire, when the FPC 17 is in close contact with the back surface of the display panel, there is a metal between the bending portion and the body portion. The wiring exposed portion A is generated.

The metal wiring exposed portion A is affected by electromagnetic interference (EMI) and radio frequency interference (RFI) to induce signal distortion, thereby degrading the reliability of the display device.

An object of the present invention is to provide a display device including a flexible printed circuit capable of effectively shielding noise and preventing cracks due to bending.

In order to achieve the above object, the present invention includes a display panel and a flexible printed circuit provided along at least one edge of the display panel, wherein the flexible printed circuit is connected to the display panel a bonding part to be formed, a bending part connected to the bonding part for bending, a noise blocking part connected to the bending part and including a metal pattern, and a body part connected to the noise blocking part, the bending part and Provided is a display device in which a reinforcement pattern made of a soft material is disposed in a boundary region of the noise blocking unit.

Here, the reinforcement pattern may have a bar shape disposed along the boundary area.

In addition, the width of the reinforcement pattern covering the bending portion may be 0.1 mm to 0.2 mm.

The bonding part may be positioned above the display panel, and the noise blocking part and the body part may be positioned below the display panel.

Here, the metal pattern may be a mesh pattern.

And, the mesh pattern may be made of copper (Cu).

In addition, the noise blocking unit includes a base film, a metal wire disposed on the base film, an insulating layer disposed on the metal wire, the metal pattern disposed on the insulating layer, and a part of the metal pattern It may include the reinforcement pattern covering the.

In addition, the bending part may include the metal wiring, the insulating layer, and the reinforcement pattern covering a portion of the insulating layer.

The bonding part may include the metal wiring and the insulating layer.

The body part may include the base film, the metal wiring, the insulating layer, and a coverlay layer disposed on the insulating layer.

In addition, the bonding portion and the bending portion may have a length of 1 mm to 1.3 mm.

Here, the length of the noise blocking part may be 1.8 mm to 2 mm.

In addition, a rear resin covering a portion of the rear surface of the base film, a rear surface of the metal wiring of the bending part, and a portion of the rear surface of the display panel, a first adhesive layer disposed between the base film and the metal wiring, the mesh pattern, and the reinforcement pattern It may further include a second adhesive layer disposed thereon and a protective layer disposed on the second adhesive layer.

In the present invention, a noise blocking part made of a mesh pattern is formed between the bending part and the body part of the flexible printed circuit. Accordingly, it is possible to improve the reliability of the display device by preventing signal distortion.

Furthermore, by forming a reinforcing pattern made of a flexible material in the boundary region between the bending portion and the mesh pattern, it is possible to prevent damage to the metal wiring due to bending.

1 and 2 are perspective views schematically illustrating a conventional display panel and a flexible printed circuit.
3 is an exploded perspective view schematically illustrating a display device according to a first exemplary embodiment of the present invention.
4 is a diagram schematically showing a flexible printed circuit according to a first embodiment of the present invention.
5A is a view schematically showing a first surface of a flexible printed circuit according to a first embodiment of the present invention.
5B is a diagram schematically showing a second surface of the flexible printed circuit according to the first embodiment of the present invention.
6 is a diagram schematically showing a cross-section of a flexible printed circuit according to a first embodiment of the present invention.
7 is a diagram schematically showing the structure of a liquid crystal display module to which a flexible printed circuit is assembled according to the first embodiment of the present invention.
8 is an exploded perspective view schematically illustrating a display device according to a second exemplary embodiment of the present invention.
9 is a diagram schematically showing a flexible printed circuit according to a second embodiment of the present invention.
10A is a diagram schematically showing a first surface of a flexible printed circuit according to a second embodiment of the present invention.
10B is a diagram schematically showing a second surface of a flexible printed circuit according to a second embodiment of the present invention.
11 is a diagram schematically showing a cross-section of a flexible printed circuit according to a second embodiment of the present invention.
12A is a diagram schematically illustrating a connection portion between a flexible printed circuit and a display panel according to a second embodiment of the present invention.
12B is a diagram schematically showing the structure of a liquid crystal display module to which a flexible printed circuit is assembled according to a second embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<First embodiment>

3 is an exploded perspective view schematically showing a display device according to a first embodiment of the present invention, and FIG. 4 is a diagram schematically showing a flexible printed circuit according to the first embodiment of the present invention.

As shown in FIG. 3 , the display device 100 according to the first embodiment of the present invention is configured to modularize the display panel 110 and the backlight unit 120 , and the display panel 110 and the backlight unit 120 . It may be composed of a guide panel 130 , a cover bottom 150 , and a top cover 140 .

Here, the display panel 110 to which the first embodiment according to the present invention is applied is a liquid crystal display panel, an electroluminescent display panel, a plasma display panel, and an electrophoretic display. It may include various display panels such as an electrophoretic display panel and an electrowetting display panel.

Here, when the display panel 110 is an electroluminescent display panel, a plurality of gate lines and data lines, pixels defined in an intersection region thereof, and a light emitting layer provided in each pixel are selectively applied with electrical signals. It may include an array substrate including a thin film transistor (TFT), which is a switching element, an upper protective substrate, and the like, and the backlight unit 120 may be omitted.

Hereinafter, a case in which the display panel 110 is a liquid crystal panel will be described as an example.

The liquid crystal panel 110 is a part that plays a key role in image expression, and may include a first substrate 112 and a second substrate 114 bonded to each other with a liquid crystal layer interposed therebetween.

Here, for convenience of explanation, the direction in the drawing may be defined. The direction of the display surface of the liquid crystal panel 110 is referred to as a front or upper direction (or upward), and the opposite direction is referred to as a rear or downward (or downward direction). .

Although not specifically shown, on the inner surface of the first substrate 112 called a lower substrate or an array substrate, a plurality of gate wirings and data wirings intersect to define a pixel, and each pixel has a corresponding gate wiring and a thin film transistor connected to the data wiring. and a pixel electrode connected to the thin film transistor may be formed.

In addition, a color filter pattern corresponding to each pixel and a color filter pattern are covered on the inner surface of the second substrate 114, which is called an upper substrate or a color filter substrate, as a counter substrate facing the lower substrate, gate wiring, data wiring, and thin film A black matrix may be formed to cover non-display elements such as transistors.

In this case, all types of liquid crystal panels may be used as the liquid crystal panel 110 , for example, all types of liquid crystal panels such as an IPS method, an AH-IPS method, a TN method, a VA method, and an ECB method may be used. Here, when the IPS method or the AH-IPS method is used, a common electrode for forming a transverse electric field together with the pixel electrode may be formed on the first substrate 112 .

In addition, a polarizing plate (not shown) that selectively transmits only a specific light may be attached to the outer surface of the first and second substrates 112 and 114 , respectively.

A flexible printed circuit (FPC) 170 may be provided along at least one edge of the liquid crystal panel 110 .

A plurality of wiring patterns (not shown) and driving elements (not shown) are arranged and mounted on the flexible printed circuit 170 , and the flexible printed circuit 170 is turned toward the back of the liquid crystal panel 110 during the modularization process.

Also, the backlight unit 120 may be positioned between the rear surface of the liquid crystal panel 110 and the flexible printed circuit 170 .

In the liquid crystal panel 110 to which the flexible printed circuit 170 is connected as described above, when the thin film transistor selected for each gate line is turned on by the on/off signal of the gate driving circuit, the signal voltage of the data driving circuit is transmitted through the data line. The liquid crystal molecules are transferred to the corresponding pixel electrode, and the arrangement direction of the liquid crystal molecules is changed by the electric field between the pixel electrode and the common electrode, thereby indicating a difference in transmittance.

In addition, the display device 100 according to the present invention is provided with a backlight unit 120 that supplies light from a rear surface thereof so that a difference in transmittance of the liquid crystal panel 110 is expressed to the outside.

The backlight unit 120 includes an LED assembly 129, a white or silver reflective plate 125, a light guide plate 123 seated on the reflective plate 125, and an optical sheet 121 interposed thereon. .

The LED assembly 129 is positioned on one side of the light guide plate 123 to face the light incident surface of the light guide plate 123 , and the LED assembly 200 includes a plurality of LEDs 129a and a plurality of LEDs 129a at regular intervals. It includes a PCB (Printed Circuit Board: 129b) mounted to be spaced apart.

The light guide plate 123 on which the light emitted from the plurality of LEDs 129a of the LED assembly 129 is incident is the light guide plate 123 while the light incident from the LEDs 129a travels through the light guide plate 123 by total reflection several times. ) evenly spread over a wide area to provide a surface light source to the liquid crystal panel 110 .

The light guide plate 123 may include a pattern having a specific shape on the rear surface to supply a uniform surface light source.

The reflection plate 125 is located on the rear surface of the light guide plate 123 , and reflects the light passing through the rear surface of the light guide plate 123 toward the liquid crystal panel 110 to improve the luminance of the light.

The optical sheet 121 on the light guide plate 123 includes a diffusion sheet and at least one light collecting sheet, and the light passing through the light guide plate 123 is diffused or condensed to provide a more uniform surface light source to the liquid crystal panel 110 . to get hired

The liquid crystal panel 110 and the backlight unit 120 are modularized through the top cover 140, the guide panel 130, and the cover bottom 150, the top cover 140 is the upper edge of the liquid crystal panel 110 and Constructed to cover the sides.

Here, the top cover 140 has a rectangular frame shape in which a cross section is bent in a “L” shape so as to cover the upper and side edges of the liquid crystal panel 110 , and the liquid crystal panel 110 by opening the front of the top cover 140 . It is configured to display the image implemented in .

In addition, the cover bottom 150, on which the liquid crystal panel 110 and the backlight unit 120 are seated, which is the basis for assembling the entire structure of the display device 100, includes a horizontal surface and an edge portion in which the edge thereof is vertically bent.

And, seated on the cover bottom 150 and the guide panel 130 in the shape of a square frame surrounding the edges of the liquid crystal panel 110 and the backlight unit 120 is the top cover 140 and the cover bottom 150 and are combined

At this time, the top cover 140 is also referred to as a case top or top case, the guide panel 130 is also referred to as a support main or main support, or a mold frame, and the cover bottom 150 is also referred to as a bottom cover or a lower cover. also lose

On the other hand, recently, in order to realize the light and thin display device 100 , the top cover 140 and the cover bottom 150 are deleted, and the liquid crystal panel 110 is provided through an adhesive tape (not shown) and the guide panel 130 . and the backlight unit 120 may be integrally modularized.

In this case, the backlight unit 120 having the above-described structure is usually called a side light type, and according to the purpose, a plurality of LED assemblies 129 are arranged side by side on the upper front side of the reflector 125 according to the purpose of direct light (direct light). ) method is also possible, and in the case of the direct light method as described above, the light guide plate 123 may be omitted.

As shown in FIG. 4 , the flexible printed circuit 170 according to the first embodiment of the present invention includes a bonding portion 170a connected to the first substrate 112 and a bonding portion 170a connected to the bending. It may include a bending part 170b for the purpose, a noise blocking part 170c connected to the bending part 170b and including a metal pattern, and a body part 170d connected to the noise blocking part 170c.

In addition, the body portion 170d may include a connector portion (not shown) for connection with an external system.

In addition, a plurality of protrusions including the bonding portion 170a, the bending portion 170b, and the noise blocking portion 170c may be formed from the body portion 170d, and may be formed in a rectangular plate shape as a whole, but is not limited thereto. It may be formed in various shapes according to the type, size, etc. of the electronic product.

On the other hand, the surface of the flexible printed circuit 170 in contact with the first substrate 112 is defined as the second surface S2, and the surface opposite to the second surface S2 is defined as the first surface S1. can

Here, the noise blocking part 170c may be formed in a region between the bending part 170b and the body part 170d of the flexible printed circuit 170 according to the first embodiment of the present invention.

Also, the noise blocking unit 170c may include a metal pattern, and the metal pattern may be a mesh pattern MP.

That is, the noise blocking unit 170c may include a mesh pattern MP in which a plurality of metal wires form a mesh.

Here, the plurality of metal wires may be made of copper (Cu), but are not limited thereto, and may be made of a conductive metal material such as silver (Ag), gold (Au), or aluminum (Al).

Accordingly, when the flexible printed circuit 170 is folded toward the back of the liquid crystal panel 110 in the step of modularizing the display device (100 in FIG. 3 ), the bending portion 170b and the body portion ( The noise blocking unit 170c including the mesh pattern MP may be formed in the region between 170d).

Here, the mesh pattern MP may be formed in a region corresponding to the noise blocking unit 170c on the first surface S1 of the flexible printed circuit 170, but is not limited thereto.

Therefore, the metal wiring exposed area between the bending portion 170b and the body portion 170d, which is vulnerable to the effects of electromagnetic interference (EMI) and radiofrequency interference (RFI) because a large number of metal wires are dense, is meshed. By protecting it with the noise blocking unit 170c including the pattern MP, it is possible to effectively prevent signal distortion due to the influence of electromagnetic interference and radio frequency interference.

That is, the open metal layer such as the mesh pattern MP forms a structure in which a predetermined metal pattern is continuously arranged while maintaining a gap therebetween. can be obtained, and even if the mesh pattern MP is formed only on the first surface S1, it is possible to sufficiently prevent signal distortion due to the influence of electromagnetic wave interference and radio frequency interference, thereby reducing material cost and thin flexible printed circuit 170 ) can be implemented.

5A is a diagram schematically showing a first side of the flexible printed circuit according to the first embodiment of the present invention, and FIG. 5B is a diagram schematically showing the second side of the flexible printed circuit according to the first embodiment of the present invention. to be.

5A, the first surface S1 of the flexible printed circuit 170 according to the first embodiment of the present invention includes a bonding portion 170a, a bending portion 170b, a noise blocking portion 170c, It may include a body portion 170d, and a mesh pattern MP is formed on the noise blocking portion 170c.

Here, the noise blocking part 170c and the body part 170d of the first surface S1 are the liquid crystal panel (110 in FIG. 4) in the step of the flexible printed circuit 170 modularizing the display device (100 in FIG. 3). When it is tilted to the back of the , it can face the lower cover bottom (150 in FIG. 3 ).

Meanwhile, as shown in FIG. 5B , the second surface S2 of the flexible printed circuit 170 according to the first embodiment of the present invention has a bonding portion 170a, a bending portion 170b, and a noise blocking portion 170c. ) and a body portion 170d, and the mesh pattern MP is not formed on the second surface S2 of the noise blocking portion 170c.

Here, the noise blocking part 170c and the body part 170d of the second surface S2 are the liquid crystal panel (110 in FIG. 4) in the step of the flexible printed circuit 170 modularizing the display device (100 in FIG. 3). When tilted to the rear of the , it can face the backlight unit ( 120 in FIG. 3 ) at the bottom.

Even if the mesh pattern MP is formed only on the first surface S1 of the noise blocking unit 170c, signal distortion due to the influence of electromagnetic wave interference and radio frequency interference can be sufficiently prevented, so that the noise blocking unit 170c The mesh pattern MP may not be formed on the second surface S2.

Accordingly, it is possible to prevent signal distortion, reduce material cost, and realize a thin flexible printed circuit.

6 is a diagram schematically showing a cross-section of a flexible printed circuit according to a first embodiment of the present invention, and FIG. 7 is a schematic view showing the structure of a liquid crystal display module in which the flexible printed circuit according to the first embodiment of the present invention is assembled. It is a drawing shown as

As shown in FIG. 6 , the flexible printed circuit 170 according to the first embodiment of the present invention includes a bonding unit 170a and a bending unit 170b connected to the bonding unit 170a and bent for bending. It includes a noise blocking part 170c connected to the part 170b and including a metal pattern, and a body part 170d connected to the noise blocking part 170c.

Here, the noise blocking unit 170c includes a base film 171 , a metal wire 173 disposed on the base film 171 , an insulating layer 175 disposed on the metal wire 173 , and insulation It may include a mesh pattern MP disposed on the layer 175 .

Here, the base film 171 may be made of polyimide.

In addition, the metal wiring 173 may be formed by forming a copper (Cu) layer on the base film 171 and then etching the copper (Cu) layer through a photo resist process.

In addition, an insulating layer 175 may be formed on the metal wiring 173 , and the insulating layer 175 may be made of polyimide, but is not limited thereto.

In addition, a mesh pattern MP in which a plurality of metal wires form a mesh may be formed on the insulating layer 175 .

Here, the plurality of metal wires forming the mesh pattern MP may be made of copper (Cu), but are not limited thereto, and may be made of a conductive metal material such as silver (Ag), gold (Au), aluminum (Al), etc. have.

Here, the thickness of the mesh pattern MP may be 0.7 mm to 1.0 mm, but is not limited thereto.

In addition, the line width of the plurality of metal lines constituting the mesh pattern MP is not particularly limited, and may be appropriately adjusted in consideration of electromagnetic wave shielding power.

Meanwhile, the bonding portion 170a and the bending portion 170b may include a metal wiring 173 made of copper (Cu) and an insulating layer 175 made of a polyimide material on the metal wiring 173 . can

Here, the metal wiring 173 of the bonding portion 170a and the bending portion 170b may be formed on the same layer as the metal wiring 173 of the noise blocking portion 170c.

Also, the insulating layer 175 of the bonding part 170a and the bending part 170b may be formed on the same layer as the insulating layer 175 of the noise blocking part 170c.

Meanwhile, the body portion 170d includes a base film 171 , a metal wiring 173 formed on the base film 171 , an insulating layer 175 formed on the metal wiring 173 , and an insulating layer 175 . It may include a coverlay layer CL formed thereon.

Here, the base film 171 is the same layer as the base film 171 of the noise blocking unit 170C, and may be made of polyimide.

In addition, the metal wiring 173 may be formed by forming a copper (Cu) layer on the base film 171 and then etching the copper (Cu) layer through a photo resist process.

Here, the metal wiring 173 is the same layer as the metal wiring 173 of the noise blocking part 170c, the bending part 170b, and the bonding part 170a, and the noise blocking part 170c, the bending part 170b, and the bonding part. It may be electrically connected to the metal wiring 173 of the portion 170c.

In addition, an insulating layer 175 may be formed on the metal wiring 173 , and the insulating layer 175 may be made of polyimide, but is not limited thereto.

Here, the insulating layer 175 may be formed on the same layer as the insulating layer 175 of the noise blocking part 170c, the bending part 170b, and the bonding part 170a.

In addition, a coverlay layer CL for protecting the metal wiring 173 may be formed on the insulating layer 175 . The coverlay layer CL may be made of polyimide, but is not limited thereto, and may be made of a composite magnetic sheet using an oriented pressure-sensitive adhesive.

Meanwhile, although not shown, a connector part (not shown) for connection to an external system may be formed in the body part 170d.

In addition, the length including the bonding portion 170a and the bending portion 170b of the flexible printed circuit 170 according to the first embodiment of the present invention may be 1 mm to 1.3 mm, and the length of the noise blocking portion 170c is It may be 1.8 mm to 2 mm, but is not limited thereto, and may be formed in various shapes depending on the type and size of the electronic product.

As shown in FIG. 7 . The flexible printed circuit 170 according to the first embodiment of the present invention may be folded toward the rear surface of the liquid crystal panel 110 in the step of modularizing the display device ( 100 in FIG. 3 ).

That is, the first substrate 112 of the liquid crystal panel 110 and the bonding unit 170a are connected, and the noise blocking unit 170c and the body unit 170d are connected through the bending unit 170b connected to the bonding unit 170a. may be folded toward the rear surface of the liquid crystal panel 110 .

Although not shown, a backlight unit ( 120 in FIG. 3 ) may be positioned between the rear surface of the liquid crystal panel 110 and the flexible printed circuit 170 .

Meanwhile, a display wiring (not shown) may be formed on the first substrate 112 of the liquid crystal panel 110 . The display wiring may be a gate wiring (not shown) or a data wiring (not shown), and an insulating layer (not shown) may be further formed between the first substrate 112 and the display wiring.

Here, the display wiring may be formed of a metal material having a relatively low resistance, and is electrically connected to the metal wiring 173 of the flexible printed circuit 170, and a conductive pattern made of a transparent conductive material is formed on the display wiring. more may be formed.

As described above, in the display device 100 in FIG. 3 according to the first embodiment of the present invention, between the bending part 170b and the body part 170d located on the rear surface of the liquid crystal panel 110 in the step of modularizing the display device. The noise blocking unit 170c including the mesh pattern MP can be disposed in the area of

Accordingly, the metal wiring exposed area between the bending portion 170b and the body portion 170d, which is vulnerable to the effects of electromagnetic interference (EMI) and radiofrequency interference (RFI) because a large number of metal wires are dense, is meshed. By protecting the noise blocking unit 170c including the pattern MP, it is possible to effectively prevent signal distortion due to the influence of electromagnetic interference and radio frequency interference.

In addition, even if the mesh pattern MP is formed only on the first surface (S1 of FIG. 6), it is possible to sufficiently prevent signal distortion due to the influence of electromagnetic interference and radio frequency interference, thereby reducing material cost and realizing a thin flexible printed circuit. be able to

However, since the mesh pattern MP is made of copper (Cu) and has a thickness of 0.7 mm to 1.0 mm and has high rigidity, the boundary between the mesh pattern MP and the bending portion 170b during bending. A crack may be generated in the region (B).

Hereinafter, while preventing signal distortion due to the influence of electromagnetic interference and radio frequency interference, cracks occurring in the boundary region B between the mesh pattern MP and the bending portion 170b during bending can be prevented. The structure will be described in the second embodiment.

<Second embodiment>

8 is an exploded perspective view schematically illustrating a display device according to a second embodiment of the present invention, and FIG. 9 is a diagram schematically showing a flexible printed circuit according to a second embodiment of the present invention.

As shown in FIG. 8 , the display device 200 according to the second embodiment of the present invention is configured to modularize the display panel 210 and the backlight unit 220 , and the display panel 210 and the backlight unit 220 . It may be composed of a guide panel 230 , a cover bottom 250 , and a top cover 240 .

Hereinafter, a case in which the display panel 210 is a liquid crystal panel will be described as an example.

The liquid crystal panel 210 is a part that plays a key role in image expression, and may include a first substrate 212 and a second substrate 214 bonded to each other with a liquid crystal layer interposed therebetween.

Although not specifically illustrated, on the inner surface of the first substrate 212 called a lower substrate or an array substrate, a plurality of gate wirings and data wirings intersect to define a pixel, and each pixel has a corresponding gate wiring and a thin film transistor connected to the data wiring. and a pixel electrode connected to the thin film transistor may be formed.

In addition, a color filter pattern corresponding to each pixel and a color filter pattern are wrapped around the inner surface of the second substrate 214 , which is called an upper substrate or a color filter substrate, as a counter substrate facing the lower substrate, and includes gate wiring, data wiring, and a thin film. A black matrix may be formed to cover non-display elements such as transistors.

In this case, all types of liquid crystal panels may be used as the liquid crystal panel 210 , for example, all types of liquid crystal panels such as an IPS method, an AH-IPS method, a TN method, a VA method, and an ECB method may be used. Here, when the IPS method or the AH-IPS method is used, a common electrode for forming a transverse electric field together with the pixel electrode may be formed on the first substrate 212 .

In addition, a polarizing plate (not shown) that selectively transmits only a specific light may be attached to the outer surfaces of the first and second substrates 212 and 214 , respectively.

A flexible printed circuit (FPC) 270 may be provided along at least one edge of the liquid crystal panel 210 .

A plurality of wiring patterns (not shown) and driving elements (not shown) are arranged and mounted on the flexible printed circuit 270 , and the flexible printed circuit 270 is folded toward the back of the liquid crystal panel 210 during the modularization process.

Also, the backlight unit 220 may be positioned between the rear surface of the liquid crystal panel 210 and the flexible printed circuit 270 .

In the liquid crystal panel 210 to which the flexible printed circuit 270 is connected as described above, when the thin film transistor selected for each gate line is turned on by the on/off signal of the gate driving circuit, the signal voltage of the data driving circuit is transmitted through the data line. The liquid crystal molecules are transferred to the corresponding pixel electrode, and the arrangement direction of the liquid crystal molecules is changed by the electric field between the pixel electrode and the common electrode, thereby indicating a difference in transmittance.

In addition, the display device 200 according to the present invention may be provided with a backlight unit 220 that supplies light from a rear surface thereof so that a difference in transmittance displayed by the liquid crystal panel 210 is expressed to the outside.

The backlight unit 220 may include an LED assembly 229, a white or silver reflective plate 225, a light guide plate 223 seated on the reflective plate 225, and an optical sheet 221 interposed thereon. can

The LED assembly 229 is positioned on one side of the light guide plate 223 to face the light incident surface of the light guide plate 223 , and the LED assembly 200 includes a plurality of LEDs 229a and a plurality of LEDs 229a at regular intervals. It may include a PCB (Printed Circuit Board: 229b) mounted to be spaced apart.

The light guide plate 223 to which the light emitted from the plurality of LEDs 229a of the LED assembly 229 is incident is the light guide plate 223 while the light incident from the LEDs 229a travels through the light guide plate 223 by total reflection several times. ) evenly spread over a wide area to provide a surface light source to the liquid crystal panel 210 .

The light guide plate 223 may include a pattern having a specific shape on the rear surface to supply a uniform surface light source.

The reflection plate 225 is located on the rear surface of the light guide plate 223 , and reflects the light passing through the rear surface of the light guide plate 223 toward the liquid crystal panel 210 to improve the luminance of the light.

The optical sheet 221 on the light guide plate 223 includes a diffusion sheet and at least one light collecting sheet, and by diffusing or condensing the light passing through the light guide plate 223 to provide a more uniform surface light source to the liquid crystal panel 210 . to get hired

The liquid crystal panel 210 and the backlight unit 220 are modularized through the top cover 240, the guide panel 230, and the cover bottom 250, the top cover 240 is the upper edge of the liquid crystal panel 210 and Constructed to cover the sides.

Here, the top cover 240 has a rectangular frame shape in which a cross section is bent in a “L” shape to cover the upper surface and side edges of the liquid crystal panel 210 , and the liquid crystal panel 210 by opening the front of the top cover 240 . It is configured to display the image implemented in .

In addition, the cover bottom 250, on which the liquid crystal panel 210 and the backlight unit 220 are seated, which is the basis for assembling the display device 200 as a whole, is made of a horizontal plane and an edge in which the edge thereof is vertically bent.

In addition, the guide panel 230 in the shape of a square frame that is seated on the cover bottom 250 and surrounds the edges of the liquid crystal panel 210 and the backlight unit 220 includes the top cover 240 and the cover bottom 250 and the top cover 240 . are combined

At this time, the top cover 240 is also referred to as a case top or top case, the guide panel 230 is also referred to as a support main or main support, or a mold frame, and the cover bottom 250 is also referred to as a bottom cover or a lower cover. also lose

On the other hand, recently, in order to realize a light-weight and thin display device 200, the top cover 240 and the cover bottom 250 are deleted, and the liquid crystal panel 210 through the adhesive tape (not shown) and the guide panel 230. and the backlight unit 220 may be integrally modularized.

At this time, the backlight unit 220 having the above-described structure is usually called a side light type, and according to the purpose, a plurality of LED assemblies 229 are arranged side by side on the upper front side of the reflector 225 according to the purpose of direct light (direct light). ) method is also possible, and in the case of the direct light method as described above, the light guide plate 223 may be omitted.

As shown in FIG. 9 , the flexible printed circuit 270 according to the second embodiment of the present invention includes a bonding portion 270a connected to the first substrate 212 and a bonding portion 270a connected to the bending portion. It includes a bending part 270b for the purpose, a noise blocking part 270c connected to the bending part 270b and including a metal pattern, and a body part 270d connected to the noise blocking part 270c, and a noise blocking part A reinforcing pattern DP for preventing cracks is formed in a boundary region between the 270c and the bending portion 270b.

In addition, the body part 270d may include a connector part (not shown) for connection to an external system.

In addition, a plurality of protrusions including the bonding portion 270a, the bending portion 270b, and the noise blocking portion 270c may be formed from the body portion 270d, and may be formed in a rectangular plate shape as a whole, but is not limited thereto. It may be formed in various shapes according to the type, size, etc. of the electronic product.

On the other hand, a surface of the flexible printed circuit 270 in contact with the first substrate 212 is defined as a second surface S2, and a surface opposite to the second surface S2 is defined as a first surface S1. can

Here, the noise blocking part 270c may be formed in a region between the bending part 270b and the body part 270d of the flexible printed circuit 270 according to the second embodiment of the present invention.

Also, the noise blocking unit 270c may include a metal pattern, and the metal pattern may be a mesh pattern MP.

That is, the noise blocking unit 270c may include a mesh pattern MP in which a plurality of metal wires form a mesh.

Here, the plurality of metal wires may be made of copper (Cu), but is not limited thereto.

Accordingly, when the flexible printed circuit 270 is bent toward the rear surface of the liquid crystal panel 210 in the step of modularizing the display device (200 in FIG. 8 ), the bending portion 270b and the body portion ( 270d), a noise blocking unit 270c including the mesh pattern MP may be formed.

Here, the mesh pattern MP may be formed in an area corresponding to the noise blocking unit 270c on the first surface S1 of the flexible printed circuit 270, but is not limited thereto.

Accordingly, the metal wiring exposed area between the bending portion 270b and the body portion 270d, which is vulnerable to the effects of electromagnetic interference (EMI) and radiofrequency interference (RFI) because a plurality of metal wires are densely formed, is meshed. By protecting the noise blocking unit 270c including the pattern MP, it is possible to effectively prevent signal distortion due to the influence of electromagnetic interference and radio frequency interference.

That is, the open metal layer such as the mesh pattern MP forms a structure in which a predetermined metal pattern is continuously arranged while maintaining a gap therebetween. can be obtained, and even if the mesh pattern MP is formed only on the first surface S1, it is possible to sufficiently prevent signal distortion due to the influence of electromagnetic interference and radio frequency interference, thereby reducing material cost and thin flexible printed circuit 270 ) can be implemented.

In particular, on the first surface S1 of the flexible printed circuit 270 according to the second embodiment of the present invention, a reinforcement pattern DP is formed at a boundary between the noise blocking part 270c and the bending part 270b.

That is, the bar-shaped reinforcement pattern DP may be disposed along the boundary region between the mesh pattern MP and the bending part 270b.

In addition, the reinforcement pattern DP may be made of a ductility material. For example, it may be made of gold (Au), silver (Ag), or aluminum (Al), but is not limited thereto.

Accordingly, the ductility of the boundary region (B of FIG. 7 ) between the mesh pattern MP formed on the noise blocking part 270c and the bending part 270b can be improved. That is, by disposing a reinforcement pattern DP made of gold (Au), silver (Ag), aluminum (Al), etc., which is more ductile than the mesh pattern MP made of copper (Cu), the mesh pattern MP and bending are performed. It is possible to increase the ductility of the boundary region (B of FIG. 7 ) of the portion 270b.

Accordingly, due to the high rigidity of the mesh pattern MP, cracks occurring in the boundary region (B of FIG. 7 ) between the noise blocking unit 270c and the bending unit 270b during bending can be prevented. there will be

10A is a diagram schematically showing a first side of a flexible printed circuit according to a second embodiment of the present invention, and FIG. 10B is a diagram schematically showing a second side of a flexible printed circuit according to a second embodiment of the present invention. to be.

10A, the first surface S1 of the flexible printed circuit 270 according to the second embodiment of the present invention includes a bonding portion 270a, a bending portion 270b, a noise blocking portion 270c, It may include a body portion 270d.

Here, the mesh pattern MP is formed in the noise blocking unit 270c.

In particular, a reinforcement pattern DP is formed in the boundary region between the noise blocking portion 270c and the bending portion 270b on which the mesh pattern MP is formed.

That is, a bar-shaped reinforcement pattern DP may be disposed along the boundary between the mesh pattern MP and the bending portion 270b.

Here, the width w of the reinforcement pattern DP covering the bending portion 270b may be 0.1 mm to 0.2 mm, but is not limited thereto.

Here, the noise blocking part 270c and the body part 270d of the first surface S1 are formed by the flexible printed circuit 270 in the step of modularizing the display device (200 in FIG. 8 ) to the liquid crystal panel (210 in FIG. 9 ). When it is tilted to the back of the , it can face the lower cover bottom (250 in FIG. 8).

Meanwhile, as shown in FIG. 10B , the second surface S2 of the flexible printed circuit 270 according to the first embodiment of the present invention has a bonding portion 270a, a bending portion 270b, and a noise blocking portion 270c. ) and a body part 270d, and the mesh pattern MP and the reinforcement pattern DP are not formed on the second surface S2 of the noise blocking part 270c.

Here, the noise blocking part 270c and the body part 270d of the second surface S2 are formed in the liquid crystal panel (210 in FIG. 9) in the step of the flexible printed circuit 270 modularizing the display device (200 in FIG. 8). When it is tilted toward the back of the , it may face the backlight unit 220 in FIG. 8 .

Even if the mesh pattern MP is formed only on the first surface S1 of the noise blocking unit 270c, it is possible to sufficiently prevent signal distortion due to the influence of electromagnetic interference and radio frequency interference. The mesh pattern MP may not be formed on the second surface S2.

Accordingly, it is possible to prevent signal distortion, reduce material cost, and realize a thin flexible printed circuit.

11 is a diagram schematically showing a cross-section of a flexible printed circuit according to a second embodiment of the present invention, and FIG. 12A is a diagram schematically showing a connection portion between a flexible printed circuit and a display panel according to a second embodiment of the present invention. 12B is a diagram schematically showing the structure of a liquid crystal display module to which a flexible printed circuit according to a second embodiment of the present invention is assembled.

11, the flexible printed circuit 270 according to the second embodiment of the present invention includes a bonding portion 270a, a bending portion 270b connected to the bonding portion 270a, and bending for bending. It includes a noise blocking part 270c connected to the part 270b and including a metal pattern, and a body part 270d connected to the noise blocking part 270c, and a noise blocking part 270c and a bending part 270b. A reinforcing pattern DP is formed in the boundary region.

Here, the noise blocking unit 270c includes a base film 271 , a metal wire 273 disposed on the base film 271 , an insulating layer 275 disposed on the metal wire 273 , and insulation It may include a mesh pattern MP disposed on the layer 275 and a reinforcement pattern DP covering a portion of the mesh pattern MP.

Here, the base film 271 may be made of polyimide.

In addition, the metal wiring 273 may be formed by forming a copper (Cu) layer on the base film 271 and then etching the copper (Cu) layer through a photo resist process.

In addition, an insulating layer 275 may be formed on the metal wiring 273 , and the insulating layer 275 may be made of polyimide, but is not limited thereto.

In addition, a mesh pattern MP in which a plurality of metal wires form a mesh may be formed on the insulating layer 275 .

Here, the plurality of metal lines constituting the mesh pattern MP may be made of copper (Cu), but is not limited thereto.

Here, the thickness of the mesh pattern MP may be 0.7 mm to 1.0 mm, but is not limited thereto.

In addition, the line width of the plurality of metal lines constituting the mesh pattern MP is not particularly limited, and may be appropriately adjusted in consideration of electromagnetic wave shielding power.

In addition, the reinforcement pattern DP covering a part of the mesh pattern MP may be made of a ductility material. For example, it may be made of gold (Au), silver (Ag), or aluminum (Al), but is not limited thereto.

That is, a bar-shaped reinforcement pattern DP may be disposed along the boundary between the mesh pattern MP and the bending portion 270b.

On the other hand, the bonding portion 270a and the bending portion 270b may include a metal wiring 273 made of copper (Cu) and an insulating layer 275 made of a polyimide material on the metal wiring 273 . can

Here, the reinforcing pattern DP covering a portion of the bending portion 270b may be made of a ductility material. For example, it may be made of gold (Au), silver (Ag), or aluminum (Al), but is not limited thereto.

That is, a bar-shaped reinforcement pattern DP may be disposed along the boundary between the mesh pattern MP and the bending portion 270b.

Here, the width w of the reinforcement pattern DP covering the bending portion 270b may be 0.1 mm to 0.2 mm, but is not limited thereto.

Here, the metal wiring 273 of the bonding part 270a and the bending part 270b may be formed on the same layer as the metal wiring 273 of the noise blocking part 270c.

Also, the insulating layer 275 of the bonding part 270a and the bending part 270b may be formed on the same layer as the insulating layer 275 of the noise blocking part 270c.

Meanwhile, the body portion 270d includes a base film 271 , a metal wiring 273 formed on the base film 271 , an insulating layer 275 formed on the metal wiring 273 , and an insulating layer 275 . It may include a coverlay layer CL formed thereon.

Here, the base film 271 is the same layer as the base film 271 of the noise blocking unit 270C and may be made of polyimide.

In addition, the metal wiring 273 may be formed by forming a copper (Cu) layer on the base film 271 and then etching the copper (Cu) layer through a photo resist process.

Here, the metal wiring 273 is the same layer as the metal wiring 273 of the noise blocking part 270c, the bending part 270b, and the bonding part 270a, and the noise blocking part 270c, the bending part 270b, and the bonding part. It may be electrically connected to the metal wiring 273 of the part 270a.

In addition, an insulating layer 275 may be formed on the metal wiring 273 , and the insulating layer 275 may be made of polyimide, but is not limited thereto.

Here, the insulating layer 275 may be formed on the same layer as the insulating layer 275 of the noise blocking part 270c, the bending part 270b, and the bonding part 270a.

In addition, a coverlay layer CL for protecting the metal wiring 273 may be formed on the insulating layer 275 . The coverlay layer CL may be made of polyimide, but is not limited thereto, and may be made of a composite magnetic sheet using an oriented pressure-sensitive adhesive.

Meanwhile, although not shown, a connector part (not shown) for connection to an external system may be formed in the body part 270d.

In addition, the length including the bonding portion 270a and the bending portion 270b of the flexible printed circuit 270 according to the second embodiment of the present invention may be 1 mm to 1.3 mm, and the length of the noise blocking portion 270c is It may be 1.8 mm to 2 mm, but is not limited thereto, and may be formed in various shapes depending on the type and size of the electronic product.

12A , looking at the connection structure of the liquid crystal panel 210 and the flexible printed circuit 270 in more detail, the first substrate 212 of the liquid crystal panel 210 and the flexible printed circuit 270 may be connected to each other. can

Here, a display wiring (not shown) may be formed on the first substrate 212 of the liquid crystal panel 210 . The display wiring may be a gate wiring (not shown) or a data wiring (not shown), and an insulating layer (not shown) may be further formed between the first substrate 212 and the display wiring.

Here, the display wiring may be formed of a metal material having a relatively low resistance, and is electrically connected to the metal wiring 273 of the flexible printed circuit 270 , and a conductive pattern made of a transparent conductive material is formed on the display wiring. more may be formed.

In addition, a portion of the rear surface of the first substrate 212 of the liquid crystal panel 210 and a portion of the base film 271 of the second surface S2 of the flexible printed circuit 270 and the exposed metal wiring 273 are covered. A backing resin SR may be disposed.

The base film 271 and the back resin SR are for maintaining the electrical insulation state of the metal wiring 273, and a resin-based material including polyimide or polyester may be used. In addition, it may be formed in the form of a film by accommodating polyimide having relatively excellent heat resistance.

A first adhesive layer 272 may be disposed between the base film 271 and the metal wiring 273 , and a protective layer 279 made of polyimide may be formed on the reinforcement pattern DP. can

Here, between the reinforcing pattern DP and the protective layer 279, a step difference due to the formation of the reinforcing pattern DP is removed, and a second method for improving adhesion with the protective layer 279 disposed on the reinforcing pattern DP is improved. An adhesive layer 277 may be formed.

Through such a structure, it is possible to stably increase the ductility of the boundary region B between the noise blocking portion 270c and the bending portion 270b on which the mesh pattern MP is formed.

As shown in Figure 12b. The flexible printed circuit 270 according to the second embodiment of the present invention may be folded toward the rear surface of the liquid crystal panel 210 in the step of modularizing the display device (200 in FIG. 8 ).

That is, the first substrate 212 of the liquid crystal panel 210 and the bonding part 270a are connected, and the noise blocking part 270c and the body part 270d are connected through the bending part 270b connected to the bonding part 270a. may be folded toward the rear surface of the liquid crystal panel 210 .

At this time, in the display device 200 in FIG. 8 according to the second embodiment of the present invention, the reinforcement pattern DP is formed in the boundary region B between the noise blocking portion 270c and the bending portion 270b in which the mesh pattern MP is formed. ) is formed, and due to the high rigidity of the mesh pattern MP, cracks occurring in the boundary region B between the noise blocking unit 270c and the bending unit 270b during bending can be prevented. do.

In this way, the display device (200 in FIG. 8) according to the second embodiment of the present invention includes the bending part 270b located on the rear surface of the liquid crystal panel 210 in the step of modularizing the display device (200 in FIG. 8); The noise blocking unit 270c including the mesh pattern MP is disposed in the area between the body parts 270d, and a plurality of metal wires are densely formed to cause electromagnetic interference (EMI) and radiofrequency interference (RFI). The noise blocking unit 270c including the mesh pattern MP protects the metal wiring exposed area between the bending portion 270b and the body portion 270d, which is vulnerable to the effects of interference, effectively preventing electromagnetic interference and radio frequency interference. It is possible to prevent signal distortion due to influence.

In addition, even if the mesh pattern MP is formed only on the first surface (S1 of FIG. 10A ), signal distortion due to the influence of electromagnetic interference and radio frequency interference can be sufficiently prevented, thereby reducing material cost and realizing a thin flexible printed circuit. be able to

Furthermore, a reinforcement pattern DP is formed in the boundary region B between the mesh pattern MP and the bending part 270b, and due to the high rigidity of the mesh pattern MP, the mesh pattern MP during bending. It is possible to prevent cracks occurring in the boundary region B of the bending portion 270b.

.

Although the above has been described with reference to the preferred embodiment of the present invention, those skilled in the art can variously modify and change the present invention within the scope without departing from the spirit and scope of the present invention described in the claims below. You will understand that it can be done.

270: flexible printed circuit 270a: bonding unit
270b: bending part 270c: noise blocking part
270d: body portion 271: base film
273: metal wiring 275: insulating layer
MP: mesh pattern CL: coverlay
DP: reinforcement pattern

Claims (14)

a display panel;
a flexible printed circuit provided along at least one edge of the display panel;
The flexible printed circuit,
A bonding portion connected to the display panel, a bending portion connected to the bonding portion for bending, a body portion in which a metal wiring is formed, and a metal pattern formed between the bending portion and the body portion, when bending and a noise blocking unit that blocks noise applied to the metal wiring exposed to the outside,
A reinforcing pattern made of a soft material is disposed in a boundary region of the bending part and the noise blocking part,
The flexible printed circuit includes a base film, a back resin covering a portion of the back surface of the base film, a back surface of the metal wiring of the bending part, and a back surface of the display panel, and a first adhesive layer disposed between the base film and the metal wiring and a second adhesive layer disposed on the metal pattern and the reinforcing pattern, and a protective layer disposed on the second adhesive layer.
The method of claim 1,
The reinforcing pattern is a bar shape disposed along the boundary area.
The method of claim 1,
A display device having a width of 0.1 mm to 0.2 mm in which the reinforcement pattern covers the bending part.
4. The method according to any one of claims 1 to 3,
The bonding part is positioned above the display panel, and the noise blocking part and the body part are positioned below the display panel.
5. The method of claim 4,
The metal pattern is a mesh pattern.
6. The method of claim 5,
The mesh pattern is a display device made of copper (Cu).
The method of claim 1,
The noise blocking unit may include the base film on which the metal wiring is disposed, the insulating layer disposed on the metal wiring, the metal pattern disposed on the insulating layer, and the reinforcement covering a part of the metal pattern A display containing a pattern.
8. The method of claim 7,
and the bending part includes the metal wiring, the insulating layer, and the reinforcement pattern covering a portion of the insulating layer.
9. The method of claim 8,
The bonding part may include the metal wiring and the insulating layer.
10. The method of claim 9,
The body portion may include the base film, the metal wiring, the insulating layer, and a coverlay layer disposed on the insulating layer.
The method of claim 1,
The length of the bonding part and the bending part is 1 mm to 1.3 mm.
12. The method of claim 11,
The length of the noise blocking part is 1.8 mm to 2 mm.
delete The display device of claim 10 , wherein the coverlay layer is positioned on the same plane as the noise blocking part.

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