KR20070012077A - Flexible printed circuit board and liquid crystal display including the same - Google Patents

Abstract

A flexible printed circuit board and a liquid crystal display including the same are provided to reduce the cost and the thickness of a slide type mobile phone by reducing use of a connector used for interface between a sliding module and a main module by extending an interface part and a connector connecting part from a circuit area of a flexible printed circuit board. A flexible printed circuit board includes a base film. A driving IC(Integrated Chip) connecting part(121a) is connected with an input terminal of a driving IC providing a driving signal to a display part. A circuit area(121b) has a circuit device for transmitting a predetermined data signal and a control signal to the driving IC. A connector connecting part(121d) is connected with a connector(174b) mechanically contacting with a key input unit. An interface area(121c) connects the circuit area with the connector connecting part.

Description

Flexible Printed Circuit Board and Liquid Crystal Display Including The Same

1A is a perspective view of a liquid crystal display device including a flexible printed circuit board according to an exemplary embodiment of the present invention.

FIG. 1B is an exploded perspective view of the liquid crystal display shown in FIG. 1A.

2A is a plan view illustrating a flexible printed circuit board according to an exemplary embodiment of the present invention.

FIG. 2B is a cross-sectional view of the flexible printed circuit board of FIG. 2A taken along the line AA ′. FIG.

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

1: liquid crystal display 10: sliding module

20: main module 110: first top frame

112: first key input unit 124: window

120: flexible printed circuit board 121a: drive IC connection

121b: circuit area 121c: interface portion

121d: connector connection 130: first printed circuit board

131: driving IC 133: thin film transistor array panel

134: common electrode display panel 135: liquid crystal panel

136: storage container 140: the first heart

144: first hole 150: sliding plate

160: second frame 162: second key input unit

164: second hole 170: second printed circuit board

172: second keypad 174a: connector

174b: connector 180: second heart

182: antenna 190: battery

The present invention relates to a flexible printed circuit board and a liquid crystal display including the same, and more particularly, to a flexible printed circuit board and a liquid crystal display including the same can reduce the thickness of the slide-type mobile phone.

Liquid crystal display (LCD) is a display device that displays the image information by using the electrical and optical properties of the liquid crystal injected into the liquid crystal panel, compared to electronic products consisting of cathode ray tube (CRT) It has the advantages of low power consumption, light weight and small volume. Therefore, liquid crystal displays have been widely applied to various fields such as display devices of portable computers, monitors of desktop computers, and monitors of high-definition video devices.

A liquid crystal display is generally classified into a liquid crystal panel assembly and a backlight assembly. The liquid crystal panel assembly includes a liquid crystal panel formed by injecting a liquid crystal material having anisotropic dielectric constant between a thin film transistor array panel and a color filter panel, and a chip on glass (COG) method. A driving IC mounted on the liquid crystal panel and applying a driving signal to the gate line and the data line formed on the liquid crystal panel, and a printed circuit board transmitting the predetermined data and control signals to the driving IC and the driving IC. It may include a flexible printed circuit board for. The liquid crystal panel assembly is combined with a backlight assembly including a lamp assembly and various optical sheets to form a liquid crystal display device.

In this case, a circuit component such as the driving IC is usually mounted on a printed circuit board (PCB), but in the case of a liquid crystal display device provided in a small display device such as a mobile phone, a flexible printed circuit board is used for more efficient space arrangement. (FPC: Flexible Printed Circuits). Particularly, in the case of a liquid crystal display device such as a slide type mobile phone, one end of the flexible printed circuit board is connected to the liquid crystal panel, and the other end of the flexible printed circuit board is connected to the printed circuit board on which various circuit elements are mounted. The liquid crystal panel and the printed circuit board are electrically connected.

At this time, one end of the liquid crystal panel and the flexible printed circuit board, the other end of the flexible printed circuit board and the printed circuit board are connected by a connector, respectively.

However, when connecting the flexible printed circuit board using the connector, there is a problem that not only increases the overall thickness of the mobile phone due to the use of the connector, but also increases the cost due to the use of the connector.

An object of the present invention is to provide a flexible printed circuit board that can reduce the thickness of the slide-type mobile phone.

Another object of the present invention is to provide a liquid crystal display device including the flexible printed circuit board.

However, the technical problems to be achieved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the following description.

According to one or more exemplary embodiments, a flexible printed circuit board may include a base film, a driving IC connection unit connected to an input terminal of a driving IC providing a driving signal to a display unit, and a predetermined data signal to the driving IC. And a circuit region in which a circuit element for transmitting a control signal is mounted, a connector connection portion to which a connector which can be mechanically contacted with a key input portion, and an interface region connecting the circuit region and the connector connection portion are included.

According to another aspect of the present invention, there is provided a liquid crystal display device including a sliding module including a display unit, a main module including a key input unit for receiving a selection value from a user, A driving IC connection unit connected to an input terminal of a driving IC providing a driving signal to the display unit, a circuit region in which a circuit element for transmitting a predetermined data signal and a control signal to the driving IC is mounted, and a mechanical contact with the key input unit It includes a connector connecting portion to which the connector is connected, and an interface region connecting the circuit region and the connector connection portion, and a flexible printed circuit board connecting the display unit and the key input unit.

Specific details of other embodiments are included in the detailed description and drawings.

Advantages and features of the present invention, and methods for achieving them will be apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various forms. It is provided to fully convey the scope of the invention to those skilled in the art, and the invention is defined only by the scope of the claims. Like reference numerals refer to like elements throughout.

Examples of the liquid crystal display device used in the present invention include a portable multimedia player (PMP), a personal digital assistant (PDA), a digital versatile disk (DVD) player, a cellular phone, and a notebook computer. Hereinafter, the liquid crystal display device of the present invention will be described using the slide type mobile phone as an example in the present invention. However, the present invention is not limited thereto and may include the aforementioned liquid crystal display devices.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of the present invention;

In the form of a slide-type mobile phone, the front sliding module having a display unit on the front side can be pushed up to expose a key input unit formed on the front side of the main module, and the sliding module having a key input unit on the front side is pushed down. There is a form of moving to expose the display unit formed on the front main module rear. Hereinafter, the embodiment of the present invention will be described the liquid crystal display device of the present invention by taking the first type of slide type mobile phone as an example.

First, FIG. 1A is a perspective view of a liquid crystal display device 1 having a flexible printed circuit board according to an embodiment of the present invention, and FIG. 1B is an exploded perspective view of the liquid crystal display device 1 shown in FIG. 1A.

1A and 1B, a liquid crystal display device 1 according to an exemplary embodiment of the present invention may include a sliding module 10 mounted on an upper portion of the main module 20 and a main module including various key input units. 20) and a sliding plate 150 for fastening the sliding module 10 and the main module 20 in a sliding manner.

The sliding module 10 may be mounted on the upper portion of the main module 20 to move relatively upward, and expose the second key input unit 162 provided on the front surface of the main module 20 during the movement. The sliding module 10 may include a first signal frame 110 having a window for exposing the display unit and a first key input unit 112, and a command signal for an applied key among the keys of the first key input unit 112. A first printed circuit board 130 including a first keypad (not shown) and a display unit for generating a first hearth, and a first shuttle coupled to the first top frame 110 to receive the first printed circuit board 130 ( 140).

Here, the display unit includes a liquid crystal panel assembly, a backlight unit, an upper accommodating container (not shown) for accommodating the liquid crystal panel assembly and the backlight unit, and a lower accommodating container coupled to the upper accommodating container.

The liquid crystal panel assembly is interposed between the thin film transistor array panel 133 and the thin film transistor array panel 133 at regular intervals so as to be interposed between the thin film transistor array panel 133 and the thin film transistor array panel 133 and the common electrode panel 134. And a liquid crystal panel 135 including a liquid crystal layer (not shown) oriented in a direction, a driving IC 131, a flexible printed circuit board 120, and the like.

 The liquid crystal panel 135 is a device for displaying image information such as letters, numbers, and arbitrary icons by adjusting the transmittance of light passing through a liquid crystal layer (not shown) according to the intensity of the applied voltage. The thin film transistor array panel 133 The common electrode panel 134 and a liquid crystal (not shown) are included.

The thin film transistor array panel 133 includes a plurality of gate lines, data lines, and pixel electrodes. The gate lines extend in the row direction to carry the gate signal, and the data lines extend in the column direction and carry the data signal. Pixel electrodes are formed for each pixel on the gate line and the data line. In addition, each pixel includes a thin film transistor connected to a gate line, a data line, and a pixel electrode to operate as a switching element.

Here, the switching element is formed at the intersection of the gate line and the data line, and the sustain capacitor and the liquid crystal capacitor are connected to the output terminal of the switching element. In addition, the switching element is implemented as a thin film transistor having amorphous silicon and poly-silicon as a channel layer.

The common electrode display panel 134 is disposed on the thin film transistor array panel 133 and includes a red, green, or blue color filter in a region corresponding to the pixel electrode so that colors can be displayed for each pixel. The color filter may be formed above or below the pixel electrode. In addition, a common electrode made of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO) is formed on the color filter.

The liquid crystal layer (not shown) is filled between the common electrode panel 134 and the thin film transistor array panel 133 and has a dielectric anisotropy. The liquid crystal layer (not shown) has a thickness of about 5 μm and has a twisted nematic (TN) arrangement. The liquid crystal layer (not shown) adjusts the transmittance of light passing through the liquid crystal layer (not shown) by changing the arrangement direction by a voltage applied from the outside.

Meanwhile, the thin film transistor array panel 133, the common electrode panel 134, and the liquid crystal layer (not shown) constituting the liquid crystal panel 135 constitute a liquid crystal capacitor, and the liquid crystal capacitor configured as described above is common to the output terminal of the switching element. It is connected to a voltage or reference voltage.

The driving IC 131 receives a gate control signal, a data control signal, a data signal related thereto, and the like from the first printed circuit board 130 and the second printed circuit board 170 through an input terminal, and gates through an output terminal. The driving signal and the data driving signal are provided to the gate line and the data line formed on the thin film transistor array panel 133, respectively. As a result, a desired image may be implemented on the liquid crystal panel 135.

The driving IC 131 is mounted on the thin film transistor array panel 133 other than the image display region corresponding to the common electrode display panel 134 of the thin film transistor array panel 133, and the output terminal thereof extends from the image display region. It is mounted by a COG (chip on glass) method so as to be connected to the gate line and the data line, respectively. Accordingly, as described above, the gate driving signal and the data driving signal generated by the driving IC 131 are transmitted to each pixel formed in the image display area of the thin film transistor array panel 133.

The flexible printed circuit board (FPCB) 120 is a type of a printed circuit board (PCB) that connects various electronic components or supports the components according to the circuit design of the electrical wiring to the printed circuit board. Unlike conventional printed circuit boards, they are flexible. The flexible printed circuit board 120 may include an output pad region electrically connected to an input terminal of a driving IC mounted on a liquid crystal panel, and a circuit region in which signals may be transmitted between various elements mounted on the flexible printed circuit board. Include. In addition, the flexible printed circuit board 120 according to the embodiment of the present invention is formed at one end of the interface region and the interface region extending from the circuit region and is connected to the connector of the second printed circuit board 170 to be described later. It can include an area. In the flexible printed circuit board, when the sliding module 10 is coupled, the interface area and the input pad area are exposed to the outside of the first heart 140 through holes formed in the first heart 140. A more detailed description of the flexible printed circuit board will be described later with reference to FIGS. 2A and 2B.

The back light unit (BLU) may include first optical sheets, a lamp assembly, a light guide plate, a reflective sheet, and second optical sheets, although not shown in the drawing.

Here, the light guide plate serves to guide the light emitted from the lamp assembly. The light guide plate is formed of a panel of a plastic-based transparent material such as acrylic to propagate light generated from the lamp assembly toward the liquid crystal panel 135 seated on the light guide plate. Accordingly, various patterns for converting the traveling direction of light incident into the light guide plate toward the liquid crystal panel 135 may be printed on the rear surface of the light guide plate.

The lamp assembly is inserted into one side of the light guide plate in the upper housing. Lamps used in the lamp assembly may include, for example, a light emitting diode (LED), a cold cathode fluorescent lamp (CCFL), and an external electrofluorescent lamp (EEFL).

The reflective sheet is installed on the lower surface of the light guide plate to reflect the light emitted to the bottom of the light guide plate to the top. The reflective sheet is located on the lower surface of the light guide plate, and reflects the light not reflected by the fine dot pattern on the back surface of the light guide plate toward the exit surface of the light guide plate, thereby reducing the optical loss of the light incident on the liquid crystal panel 135 and simultaneously It serves to improve the uniformity of the light transmitted to the exit surface.

The first optical sheets are mounted on the upper surface of the light guide plate to diffuse and collect light transmitted from the light guide plate. The first optical sheets include a diffusion sheet, a prism sheet, a protective sheet, and the like.

The diffusion sheet located between the light guide plate and the prism sheet prevents light from being partially concentrated by dispersing light incident from the light guide plate. The prism sheet has a triangular prism with a regular arrangement on the upper surface, and is usually composed of two sheets, and each prism array is arranged so as to cross each other at a predetermined angle, so that the light diffused from the diffusion sheet is a liquid crystal panel. Condensing in a direction perpendicular to the (135). As a result, the light passing through the prism sheet almost runs vertically so that the luminance distribution on the protective sheet is uniformly obtained. The protective sheet formed on the prism sheet not only serves to protect the surface of the prism sheet, but also serves to diffuse light in order to make the distribution of light uniform. In addition, a black line (not shown) may be formed along the edge of the protective sheet to prevent bright lines or light leakage generated at the edge of the display area of the liquid crystal panel 135.

Here, in the case of the small liquid crystal display device 1, one lamp is usually installed on the side of the light guide plate, but as the liquid crystal display device 1 becomes larger, a plurality of lamps may be installed in one lamp assembly to obtain sufficient luminance. .

The liquid crystal panel assembly is mounted on the first optical sheets and is mounted in the light guide plate together with the first optical sheets.

The upper storage container has a sidewall formed along the edge of the rectangular opening, and a predetermined locking protrusion (not shown) is formed in the sidewall to accommodate and fix the liquid crystal panel assembly and the backlight unit. Prevents bending The flexible printed circuit board 120 of the liquid crystal panel assembly is bent around one side wall of the upper storage container. Here, the shape of the upper housing container may be variously modified according to a method of accommodating the backlight unit or the liquid crystal panel assembly in the upper housing container.

The upper container may be hooked with the lower container (not shown). For example, a hook (not shown) is formed along an outer surface of the side wall of the upper container, and a hook corresponding to the hook (not shown) is formed. Insertion holes (not shown) may be formed on the side of the lower housing. Accordingly, by combining the lower storage container with the lower storage container from the bottom of the upper storage container, the hook (not shown) formed in the upper storage container enters the hook insertion hole (not shown) of the lower storage container to fasten the upper storage container and the lower storage container. Can be. The present invention is not limited thereto, and the position of the hook (not shown) may be located in the lower housing and the hook insertion hole (not shown) may be formed in the upper housing. In addition, the combination of the upper storage container and the lower storage container may be modified in various forms.

The main module 20 is mounted under the sliding module 10, and the second key input unit 162 provided on the front surface of the main module 20 is exposed as the sland module moves upward. The main module 20 has a second key pad 172 on which the second key input unit 162 is formed, and a second keypad 172 for generating a command signal for an applied key among the keys of the second key input unit 162. ), A second printed circuit board 170 having a connector which can be connected to the connector connection part of the flexible printed circuit board 120, and a second printed circuit board 170 which is combined with the second top frame 160 to receive the second printed circuit board 170. It is configured to include two hearts 180.

In addition, the predetermined area of the second upper frame 160 is formed with a hole having a length and a width greater than the width and thickness of the flexible printed circuit board 120. When the above-described sliding module 10 is coupled, the interface portion and the connector connection portion of the flexible printed circuit board 120 exposed to the outside through the hole of the first heart 140, the hole 164 formed in the second upper frame 160 ) Is connected to the connector 174a of the second printed circuit board 170.

Next, the flexible printed circuit board 120 according to the embodiment of the present invention will be described with reference to FIGS. 2A and 2B. 2A is a plan view of a flexible printed circuit board 120 according to an exemplary embodiment of the present invention, and FIG. 2B is a cross-sectional view taken along the line AA ′ of FIG. 2A.

2A and 2B, the flexible printed circuit board 120 may include a base film 122 made of an insulating material such as polyimide or polyester, and a coverlay for insulation. coverlay 123, a bonding sheet 124 for bonding the copper foil layer 126, a copper foil layer 126 having a circuit pattern (not shown) and a circuit pattern formed on the copper foil layer 126 (not shown) Insulation ink (PSR Ink) for protecting the photo is formed by being sequentially stacked on both sides of the base film 122.

Here, the copper foil layer 126 may be formed in a single layer or multiple layers on one or both surfaces of the flexible printed circuit board 120. A circuit pattern (not shown) is formed on the copper foil layer 126. The circuit pattern (not shown) of the copper foil layer 126 is formed by applying a metal material having excellent electrical conductivity such as copper to the base film 122. It is formed through an etching process. Circuit patterns (not shown) formed on the copper foil layers 126 on both sides may be electrically connected to each other through via holes (VH) (not shown) generated through the bonding sheet 124 and the base film 122. Can be.

Such a laminated structure forms the circuit region 121b of the flexible printed circuit board 120. At one end of the circuit region 121b, a plurality of output pads extending from a circuit pattern (not shown) are formed. The output pads are disposed at predetermined intervals in the output pad area, and the output pads are electrically connected to input terminals of the driving IC 131 mounted on the liquid crystal panel 135.

The base film 122 and the coverlay layer 123 at the end of the output pad extend from the output pad to form the connection portion 121a of the driving IC 131. As described above, the driver IC 131 connecting portion 121a formed of the base film 122 and the coverlay 123 layer has a thinner laminated structure than the circuit region 121b, thereby making it easier to connect with the driver IC 131. .

On the other hand, the interface portion 121c is formed on the other side of the circuit region 121b by extending from the circuit region 121b. The interface unit 121c is a portion connecting the circuit region 121b of the flexible printed circuit board 120 and the second printed circuit board 170 of the main module 20. The sliding module 10 and the main module 20 are connected to each other. After the) is combined, it is also the part where the bending occurs. Therefore, the interface portion 121c minimizes the physical friction between the layers, and at least one of the bonding sheet 124, the copper foil layer 126, and the insulating ink layer 127 is removed to bend well.

At the end of the interface portion 121c, a connector connection portion 121d that can be connected to the connector 174a provided on the second printed circuit board 170 is formed. The connector connection portion 121d has a laminate structure substantially the same as the laminate structure of the circuit region 121b mentioned above. A connector 174b paired with a connector 174a provided on the second printed circuit board 170 may be connected to the connector connection portion 121d. For example, when a female connector is provided on the second printed circuit board 170, a male connector may be connected to the connector connection portion 121d of the flexible printed circuit board 120. As another example, when a male connector is provided on the second printed circuit board 170, a female connector may be connected to the connector connection portion 121d of the flexible printed circuit board 120. As such, the connector connection part 121d of the flexible printed circuit board 120 is connected to the connector 174a of the second printed circuit board 170 to drive a command signal input from the second printed circuit board 170. 131 and the liquid crystal panel 135 to display an image.

As described above, according to the flexible printed circuit board 120 according to the present invention, since the interface portion 121c and the connector connecting portion 121d are formed to extend from the circuit region 121b, the flexible printed circuit board 120 is sliding, compared with the conventional slide type mobile phone. The use of the connector used in the interface of the module 10 and the main module 20 can be reduced to reduce the cost, it is possible to reduce the overall thickness of the slide-type mobile phone.

In the above-described embodiments of the present invention described with reference to the accompanying drawings, only the slide-type mobile phone has been described, but the flexible printed circuit board according to the embodiment of the present invention uses all types of liquid crystal display devices. Applicability to will be apparent to those skilled in the art. In addition, it will be understood by those skilled in the art that the present invention may be implemented in other specific forms without changing the technical spirit or essential features. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive.

According to the flexible printed circuit board and the liquid crystal display including the same according to the embodiment of the present invention made as described above, by extending the interface portion and the connector connecting portion from the circuit area of the flexible printed circuit board, The cost of using the connector used for the interface can be reduced, and the overall thickness of the slide-type mobile phone can be reduced.

Claims (6)

Base film; A driving IC connection unit connected to an input terminal of the driving IC providing a driving signal to the display unit; A circuit region in which circuit elements for transmitting a predetermined data signal and a control signal to the driving IC are mounted; A connector connection portion to which a connector which can be mechanically contacted with the key input portion is connected; And And an interface area connecting the circuit area and the connector connection part. The method of claim 1, The circuit region may include a bonding sheet, a copper foil layer having a circuit pattern formed thereon, and an insulating ink layer for protecting the circuit pattern of the copper foil layer sequentially stacked on both surfaces of the base film, and the interface unit forming the bonding sheet and the insulating ink. 15. A flexible printed circuit board, wherein at least one of the layers is selectively removed. The method of claim 1, And the circuit region extends from the driver IC connection portion, and the interface portion extends from the circuit region and is formed to be narrower than the width of the circuit region. A sliding module having a display unit; A main module including a key input unit configured to receive a selection value from a user; And A driving IC connection unit connected to an input terminal of a driving IC providing a driving signal to the display unit, a circuit region in which a circuit element for transmitting a predetermined data signal and a control signal to the driving IC is mounted, and a mechanical contact with the key input unit And a flexible printed circuit board comprising a connector connecting portion to which a connector can be connected, and an interface region connecting the circuit region and the connector connecting portion, and connecting the display portion and the key input portion. The method of claim 4, wherein The circuit region may include a bonding sheet, a copper foil layer having a circuit pattern formed thereon, and an insulating ink layer for protecting the circuit pattern of the copper foil layer sequentially stacked on both surfaces of the base film, and the interface unit forming the bonding sheet and the insulating ink. And at least one of the layers is selectively removed. The method of claim 4, wherein And wherein the circuit region extends from the driver IC connection portion, and the interface portion extends from the circuit region and is formed to be narrower than the width of the circuit region.

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