KR101074414B1 - Liquid Crystal Display Device integrated touch panel - Google Patents

Abstract

The present invention relates to a flat panel display integrated with a touch panel in which a touch screen panel (TSP) is integrated with a flat panel display (FPD). The touch panel integrated flat panel display device of the present invention is provided between an upper and a lower substrate. A liquid crystal display device having a liquid crystal layer provided thereon and a pad for a touch panel provided at an edge of the lower substrate; A touch panel attached to an upper surface of the liquid crystal display device and having a tail which is an input / output signal line connected to the pad for the touch panel; And a main FPC for connecting the LCD panel and the PCB and simultaneously connecting the pad for the touch panel with the PCB, and further adding a controller IC for the touch panel in the middle of connecting the pad for the touch panel and the main FPC. Include.

Flat Panel Display, Liquid Crystal Display, Inner Touch Panel, FPC

Description

Touch panel integrated flat panel display device {Liquid Crystal Display Device integrated touch panel}

1 is a plan view of a touch panel integrated flat panel display according to the prior art;

2 is a rear view of a touch panel integrated flat panel display according to the prior art;

3 is a cross-sectional view of a typical touch panel.

4 is a plan view of a touch panel integrated flat panel display according to the present invention;

5 is a plan view of a liquid crystal display device according to the present invention;

6 is a plan view of a flat panel display integrated with a touch panel according to another embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

102: gate wiring 103: gate drive IC

105: data wiring 106: data drive IC

113: liquid crystal display 123: touch panel

154: Tail 180: PCB

181: main FPC 190: pad for the touch panel

192: Controller IC for touch panel 193: Wiring for connection

The present invention is a touch panel integrated flat panel display in which a touch panel (TSP) is integrated into a flat panel display (FPD) including a lower polarizing plate, a liquid crystal display, and an upper polarizing plate, and in particular, an upper polarizing plate and a liquid crystal display. A touch panel integrated flat panel display having an inner type by inserting a touch panel between devices.

The touch panel is used in CAD, production system, game machine, kiosk, POS or medical field. It is an input device that replaces a keyboard or a mouse. It is a device that allows various input operations by directly touching a predetermined position while looking at the display surface.

The touch panel is classified into a capacitive type and a resistive film type according to the principle of operation. First, a capacitive touch panel is a touch point pressed by a user while the charging and discharging states of capacitance are repeated on one transparent conductive film or transparent conductive glass. A small amount of charge is accumulated by capacitive coupling between a stylus, which is a pen-type input device, and a transparent conductive film, and the amount of charge is read from four input points and converted into coordinates. The panel must be powered by the stylus.

In addition, the resistive touch panel reads a voltage or current change at a contact point generated by a user's pressing of two conductive layers while a voltage is applied to two opposing conductive layers (resistive layers) (x, y). It works by converting it to coordinate values. At this time, a busbar is required to read the voltage or current change at the contact point.

The flat panel display using the resistive touch panel may be classified into an additional type and an integrated type according to a method of attaching the touch panel to the flat panel display.

Hereinafter, a flat panel display device incorporating a resistive touch panel will be described in more detail with reference to the accompanying drawings.

1 is a plan view of a touch panel integrated flat panel display according to the prior art, FIG. 2 is a rear view of a touch panel integrated flat panel display according to the prior art, and FIG. 3 is a cross-sectional view of a general touch panel.

As shown in FIGS. 1 and 2, the touch panel integrated flat panel display includes a lower polarizing plate 32, a liquid crystal display device 13, a touch panel 23, and an upper polarizing plate 31 from below. 32, the touch panel 23 is inserted into the flat panel display including the liquid crystal display device 13 and the upper polarizing plate 31 to form an integrated body. Thus, the case where the touch panel 23 is inside the upper polarizing plate 31 is called an inner type touch panel.

For reference, the touch panel integrated flat panel display may be disposed on the upper surface of the upper polarizing plate without being inserted between the upper polarizing plate and the liquid crystal display.

Looking at the inner type touch panel integrated flat panel display in detail, the upper and lower polarizing plates 31 and 32 are optical films for polarizing light in the center, and upper and lower films for maintaining the mechanical strength of the optical films on the upper and lower surfaces of the optical film. It consists of a film.

The liquid crystal display device 13 includes upper and lower substrates 11 and 12 that face each other with a liquid crystal layer (not shown) interposed therebetween. In this case, the lower substrate 12 further includes a gate wiring 2 for transmitting a scan signal from an external driver circuit and a data wiring 5 for transmitting a data signal, and an end of the gate wiring 2 is a gate drive IC. (3), the end of the data line 5 is connected to the data drive IC (6).

Next, as illustrated in FIG. 3, the touch panel 23 includes upper and lower sheets 21 and 22, upper sheets 21, and lower sheets that serve as resistive films by including a transparent conductive film at a lower portion thereof. 22, a busbar 53 serving as an electrode for applying a voltage to two resistive layers therebetween; a tail 54 connected to the busbar 53 and extending outward; 21 and a plurality of spacers 55 spaced apart from the lower sheet 22, and an adhesive 60 for bonding the upper and lower sheets 21 and 22 facing each other.

At this time, the lower sheet 22 is composed of two layers of a base film or glass and a conductive layer (resistive film) from below, and the upper sheet 21 is made of a transparent conductive material consisting of a conductive layer (resistive film) and a base film from below. It consists of three layers of film and glare hard coating layer.

The liquid crystal display 13 and the touch panel 23 both exist independently, and to operate them, as shown in FIGS. 1 and 2, the main FPC 81 for driving the liquid crystal display 13 is shown. ) And a touch panel FPC 91 for driving the touch panel 23, respectively, and the signal line of the liquid crystal display device and the signal line of the touch panel are connected to the main FPC 81 and the touch panel FPC 91. Connect to PCB (Printed Circuit Board, 80) respectively. The PCB has a number of patterns, such as various wirings, controller ICs, power supplies, and the like for associating driving the liquid crystal display and the touch panel.

Accordingly, the PCB 80 has a main FPC connector 82 and a touch panel FPC connector 92 mounted thereon to connect the main FPC 81 and the touch panel FPC 91 to drive the touch panel 23. The controller IC (not shown) is separately embedded in the PCB and connected to the touch panel FPC through the touch panel FPC connector.

As described above, however, when the main FPC 81 and the touch panel FPC 91 are connected to the PCB 80, the process is complicated because the main FPC and the touch panel FPC must be connected to the PCB, respectively. The cost of using a separate touch panel FPC is required. This increases the cost of the process and lowers the product competitiveness. In addition, if the touch panel and the PCB are manufactured by other companies, the touch panel FPC is not compatible with the FPC connector of the PCB.

The present invention is to solve the above problems, by bonding the touch panel through the main FPC for driving the liquid crystal panel by directly bonding a flexible printed circuit (FPC) for the touch panel to the liquid crystal panel, applying an inner type touch panel The aim is to provide a flat panel display with integrated touch panel to reduce the production cost of the model and improve the product competitiveness.

The touch panel integrated flat panel display of the present invention for achieving the above object is a liquid crystal display device having a liquid crystal layer between the upper and lower substrates, and a touch panel pad at the edge of the lower substrate, and an upper surface of the liquid crystal display device. And a main FPC attached to the pad for the touch panel and connected to a tail as an input / output line, and a main FPC for connecting the LCD with the LCD and connecting the pad for the touch panel with the PCB. It is done.

In other words, instead of connecting the touch panel and the liquid crystal display device to the PCB using the touch panel FPC and the main FPC, respectively, the cost of using the touch panel FPC is reduced by connecting the touch panel and the liquid crystal display to the PCB at the same time using only the main FPC. It is characterized by.

In this case, a touch panel pad is further provided at an edge of the lower substrate of the liquid crystal display, and the tail of the touch panel is connected to the pad for the touch panel, and at the same time, the main FPC is connected. Therefore, the touch panel is connected to the PCB of the touch panel controller IC through the main FPC.

The controller IC for the touch panel may be separately embedded in the PCB, or may be directly mounted to the liquid crystal display in the form of COG.

Hereinafter, an embodiment of the present invention will be described in detail with reference to FIGS. 4 to 6.

4 is a plan view of a touch panel integrated flat panel display according to the present invention, FIG. 5 is a plan view of a liquid crystal display apparatus according to the present invention, and FIG. 6 is a plan view of a touch panel integrated flat panel display according to another embodiment of the present invention.

As shown in FIG. 4, the touch panel integrated flat panel display according to the present invention includes a liquid crystal display device 113 and a touch panel 123 attached with an adhesive to an upper surface thereof, an upper surface of the touch panel 123 and a liquid crystal device. The upper and lower polarizers (not shown) are provided on the back of the display device, respectively, and the liquid crystal display device 113 is connected to the PCB 180 through the main FPC 181, and the touch panel ( 123 is also connected to the PCB 180 by the main FPC 181 without using a touch panel FPC separately.

The PCB 180 is connected to the liquid crystal display controller IC (not shown) connected to the liquid crystal display device 113 through the main FPC 181 and connected to the touch panel 123 through the same main FPC 181. A touch panel controller IC 192 is built-in, and a timing controller for controlling the gate drive IC and the data drive IC, a common voltage (Vcom), a gate high voltage (Vgh), and a gate required by the liquid crystal display device. A power supply unit for generating driving voltages such as a low voltage Vgl is further provided.

In order to connect the touch panel 123 and the main FPC 181, the tail 154 of the touch panel 123 and the liquid crystal display 113 must be connected. In order to do so, the lower substrate edge of the liquid crystal display 113 is connected. The touch panel pad 190 is provided.

The number of the touch panel pads 190 varies depending on the tails connected to the busbars (not shown) of the touch panel. In general, two tails are used for the x-axis and two tails are provided for the y-axis. In total, four tails are used, and thus four touch panel pads 190 are provided. The busbar is required to read the voltage or current change at the input point pressed by the user.

The touch panel pad 190 may be formed at the same time as the gate line 102 and the data line 105 on the lower substrate 111 or may be formed separately from the gate line 102 and the data line 105. Do not short.

As described above, the main FPC 181 is connected to the touch panel pad 190 to which the tail extending from the bus bar of the touch panel is connected, thereby the touch panel 123 and the PCB 180 through the main FPC 181. Connect controller IC for touch panel. Therefore, the touch panel can be connected to the PCB without using a separate touch panel FPC.

In this case, the gate wiring 102 and the data wiring 105 of the liquid crystal display device also extend to the edge of the lower substrate 111 to be connected to the gate drive IC 103 and the data drive IC 106. By connecting to the PCB 180 through the FPC 181, it is connected to the LCD and the main controller IC (not shown) of the PCB.

In particular, when the gate drive IC and the data drive IC are formed by a chip on glass (COG) method directly mounted on a substrate, a flexible printed circuit film (FPC) is attached to provide signals to the drive ICs. Connect the PC with.

Specifically, the liquid crystal display device 113 includes an upper substrate on which a color filter layer for color is formed, a switching element for changing an arrangement direction of liquid crystal molecules, and a display area for displaying an image, and a pad area that is an edge thereof. It consists of a lower substrate and a liquid crystal layer formed between the two substrates, in particular, the lower substrate, as shown in Figure 5, to the plurality of gate wiring 102 and the data wiring 105 perpendicularly cross each other A thin film transistor (TFT) and a pixel electrode 117 are formed in each pixel defined by the pixel, and the gate drive IC 103 and the data drive IC 106 are formed at the ends of the gate wiring and the data wiring in a COG manner. Is further formed, one side is further provided with a touch panel pad 190 for connecting the tail of the touch panel.

At this time, in connecting the drive ICs 103 and 106 and the pad 190 for the touch panel with the PCB 180 via the main FPC 181, the drive ICs 103 and 106 and the main FPC 181 are connected. Connection and connection between the touch panel pad 190 and the main FPC 181 are bonded using an anisotropic conductive film (hereinafter referred to as an "ACF resin"). The ACF resin utilizes the principle that the conductive balls, which are conductive spheres surrounded by a thin insulating film, are dispersed in the adhesive resin, and are bonded by breaking the conductive balls of the ACF resin when pressed.

Here, the main FPC 181 transmits electrical signals (for example, video data, timing control signals and voltage signals) from a control circuit unit (not shown) to drive ICs 103 and 106 and a pad 190 for a touch panel. Wiring for transmitting to the () side is mounted.

Meanwhile, as shown in FIG. 6, the controller IC 192 for the touch panel is not mounted on the PCB 180, as shown in FIG. 4, and as shown in FIG. 6, by a COG (Chip On Glass) method. It may be mounted directly on the lower substrate 111.

In this case, the main FPC 181 is bonded with the drive ICs 103 and 106 and the controller ICs 192 for the touch panel by a thermocompression method using an ACF resin. As described above, the COG method in which the drive IC, the controller IC, and the main FPC are directly mounted on the glass substrate is generally bonded only to the bump and the ACF resin, but the structure is relatively simple compared to the TAB method and the ratio of the liquid crystal panel to the liquid crystal display device is large. There is an advantage to increase.

As described above, in the case where the controller IC 192 for the touch panel is directly mounted on the substrate, the touch panel pad 190 on the lower substrate 112 is not directly connected to the main FPC 181. The controller IC 192 for the touch panel is connected between the 190 and the main FPC 181. The controller IC 192 for the touch panel may be formed at any edge of the lower substrate, and as shown in FIG. 6, when the controller IC 192 is mounted at a distance separated from the pad 190 for the touch panel, the connection wiring 193. Connect through. In this case, the connection wiring 193 is formed on different layers so as not to be shorted with the gate wiring 102 and the data wiring 105.

Thus, the signal value of the touch panel can be transmitted to the system through the main FPC without separately manufacturing the touch panel FPC.

The present invention described above is not limited to the above-described embodiments and the accompanying drawings, and various substitutions, modifications, and changes are possible in the art without departing from the technical spirit of the present invention. It will be clear to those of ordinary knowledge.

That is, in the above embodiment, the display is limited to a small panel in which the gate drive IC and the data drive IC are collectively disposed below the liquid crystal display to minimize the size of the pad area. However, the embodiment is not limited to the small panel used as a mobile phone display. However, the technical idea of the present invention may be applied to a large or medium liquid crystal panel used as a display of a notebook or a TV.

As described above, the touch panel integrated flat panel display according to the present invention has the following effects.

First, instead of connecting the touch panel and the liquid crystal display device to the PCB through the FPC and the main FPC for the touch panel, the touch panel is connected to the fish via one main FPC. The cost by using the FPC for application can be reduced.

Second, by connecting the touch panel and the PCB using the main FPC without separately forming the touch panel FPC, the touch panel FPC can solve the compatibility problem of the FPC of the PCB.

Claims (8)

A liquid crystal display device having a liquid crystal layer between upper and lower substrates and a pad for a touch panel at an edge of the lower substrate; A touch panel attached to an upper surface of the liquid crystal display device and having a tail which is an input / output signal line connected to the pad for the touch panel; And A main FPC for connecting the LCD panel with the PCB and connecting the pad for the touch panel with the PCB; And a touch panel controller IC between the touch panel pad and the main FPC. The method of claim 1, The touch panel, The upper and lower sheets opposed to each other, Bus bars formed on the upper and lower sheets, respectively, One side is connected to the bus bar and the other side is a touch panel integrated flat panel display, characterized in that consisting of a tail connected to the pad for the touch panel. The method of claim 1, And the touch panel pad is connected to the touch panel controller IC on the PCB by the main FPC. The method of claim 3, wherein The touch panel pad and the main FPC is a touch panel integrated flat panel display, characterized in that bonded by ACF resin. delete The method of claim 1, The touch panel controller IC is mounted on the lower substrate in a chip on glass (COG) method, characterized in that the touch panel integrated flat panel display. The method of claim 1, The lower substrate further includes a gate wiring and a data wiring defining vertically crossing the pixels, and ends of the gate wiring and the data wiring are connected to the PCB by the main FPC. The method of claim 7, wherein The touch panel pad is formed simultaneously with the gate wiring or data wiring.

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