KR20180047726A - Display device having touch screen function - Google Patents

Abstract

The present invention relates to a display device having a touch screen function. According to an embodiment of the present invention, the display device having a touch screen function includes: touch sensors for generating a touch signal; sensor signal lines connected to the touch sensors; and a touch detection part receiving the touch signal through the sensor signal lines and detecting at least one of a touch state and a touch coordinate system. The touch sensors and the sensor signal lines may be formed by separating a plurality of common electrodes of the display device. In addition, the present invention includes embodiments other than the above-described embodiments. The display device can be manufactured at low costs.

Description

[0001] The present invention relates to a display device having a touch screen function,

The present invention relates to a display device having a touch screen function for detecting that various types of touch input means such as human fingers or electronic pens, for example, are approaching or contacting.

2. Description of the Related Art Generally, a touch screen is an input device (input device) provided on a display device such as a liquid crystal display (LCD), a plasma display panel (PDP), an organic light emitting diode (OLED), and an active matrix organic light emitting diode (AMOLED) device is a device for recognizing a touch input means such as a finger or a touch pen as an input signal when approaching or contacting the touch screen.

The touch input device is mounted on a mobile device such as a smart phone, a PDA (Personal Digital Assistants), and a PMP (Portable Multimedia Player). In addition, the touch input device includes navigation, netbook, notebook, DID It is widely used in many industries such as desktop computers using operating systems, Internet Protocol TV (IP TV), and military equipment.

Since the touch screen used for various display devices as described above is manufactured separately from the display device and then attached to the upper plate of the display device, the thickness of the display device with the touch screen becomes thick, There is a problem that the brightness of the display device becomes dark and the visibility is deteriorated.

The present invention can provide a touch screen function when a display device is manufactured by forming a touch sensor and a sensor signal line by using, for example, a common electrode of a display device, so that the thickness is thin, It is an object of the present invention to provide a display device having the inexpensive touch screen function.

According to another aspect of the present invention, there is provided a display device having a touch screen function, including: touch sensors for generating a touch signal; Sensor signal lines connected to the touch sensors; And a touch detection unit receiving the touch signal through the sensor signal lines and detecting at least one of a touch state and a touch coordinate system, wherein the touch sensors and the sensor signal lines include a plurality of common electrodes May be formed separately.

The display device may be an AMOLED display device, and the touch sensors and the sensor signal lines may be formed by dividing a cathode, which is a common electrode of the AMOLED display device, into a plurality of AMOLED display devices. The plurality of separated cathodes may selectively perform the role of the touch sensors and the sensor signal lines and the role of the common electrode.

The touch sensors are divided into sensing pads during touch detection and non-touch sensing pads which are not touching, and a cathode voltage which is a common voltage of the AMOLED display device may be applied to the sensing pads and the non- have. When the voltage applied to the sensing pads is different from the cathode voltage, the cathode voltage may be applied to the sensing sensing pads.

The sensor signal lines may be formed by the same material and mask constituting the touch sensors. The common electrode may be separated based on a boundary region between the pixel and the pixel. The sensor signal lines may be located above or below the boundary region, or may be located above or below the pixel.

The touch sensors and the sensor signal lines may be opposed to at least one pixel. The touch sensors may be arranged in the form of a dot matrix having a plurality of rows and a plurality of columns. On one side of the touch sensors, an overcurrent limiting circuit is provided, and the overcurrent limiting circuit may include a resistor and a switch. The touch sensors may be formed in a mesh pattern composed of a transparent conductive material or a non-transparent metal material, and may be arranged in a shape of at least one of a rectangle or a rhombus.

The touch detection unit may be any one of a touch drive IC, a display drive IC, or a touch display drive IC in which the touch drive IC and the display drive IC are integrated.

The touch detection unit may detect a touch signal based on the touch sensors and a touch capacitor Ct obtained by applying an alternating voltage to a driving capacitor Cdrv connected to one side of the touch sensors.

The touch detection unit includes: A touch capacitor (Ct) obtained by applying an alternating voltage to one side of one or more non-touching non-touch sensing pads adjacent to the upper or lower side of the touch sensing pads of the touch sensors; The touch signal can be detected based on the parasitic capacitor Cp formed between the sensor signal lines of the sensing pads.

The touch detection unit includes: A touch signal is detected based on the touch sensors and a touch capacitor Ct obtained by applying an alternating voltage to a parasitic capacitor Cp connected to one side of the touch sensors, Alternating voltage may be applied.

According to an embodiment of the present invention, a display device having a touch screen function includes touch sensors for generating a touch signal; Sensor signal lines connected to the touch sensors; Mips connected to the sensor signal lines; And a touch detection unit receiving the touch signal through the muxes and detecting at least one of a touch state and a touch coordinate, wherein the touch sensors and the sensor signal lines are connected to a common electrode of the display device by a plurality of And can be formed separately.

The touch sensors are arranged in the form of a dot matrix composed of a plurality of rows and a plurality of columns, and one of the mips selects one of the sensor signal lines connected to the touch sensors belonging to one column, One of the sensor signal lines connected to the touch sensors belonging to more than one column can be selected and connected to the touch detection unit.

The mips connected to the sensor signal lines may be manufactured by the same mask in the process for manufacturing the mux for operating the source signal line of the display device. The mips may be electrically connected to the sensor signal lines through the contact holes. The muxes may receive at least one of a selection signal, a control signal, and a required voltage output from the touch detection unit.

The touch sensors may be divided into sensing pads during touch detection and non-touch sensing pads that are not touching, and the muxes may select sensor signal lines connected to the sensing pads. A common voltage or an alternating voltage may be applied to the non-sensing pads connected to the muxes, and the touch detection unit may detect a touch signal of the sensing pads based on the common voltage or the alternating voltage.

An overcurrent limiting circuit may be provided on one side of the touch sensor, and the overcurrent limiting circuit may include a resistor and a switch, and may be installed on one side of the display device and before the input of the mugs.

An electronic device according to an embodiment of the present invention includes a display device having a touch screen function; And a processor coupled to the display device, wherein the display device having the touch screen function includes: touch sensors for generating a touch signal; Sensor signal lines connected to the touch sensors; And

And a touch detection unit that receives the touch signal through the sensor signal lines and detects at least one of a touch state and a touch coordinate system, wherein the touch sensors and the sensor signal lines include a plurality of common electrodes of the display apparatus And can be formed separately.

The electronic device may be at least one of a smart phone, a personal digital assistant (PDA), a portable multimedia player (PMP), a navigation device, a netbook, a notebook, a digital information device (DID), a desktop computer, .

According to the embodiment of the present invention, since the touch signal is detected using the common electrode of the display device, both the screen display and the touch detection can be performed by using only the display device, so that the separately added touch screen can be removed, It is possible to provide a display device having a touch screen function that is easy to manufacture and low in cost.

According to the embodiment of the present invention, since the driving chip for driving the display device and the driving chip for touch detection can be fabricated as one chip by including the function for detecting the touch signal in the driving chip for driving the display device, The manufacturing process and cost reduction are possible.

1 is a diagram illustrating a touch screen according to an embodiment of the present invention.
2 is a diagram illustrating a dot matrix type touch screen according to an embodiment of the present invention.
3 is a diagram illustrating an organic light emitting diode according to an embodiment of the present invention.
4 is a circuit diagram of a pixel according to an embodiment of the present invention.
5 is a perspective view of a pixel according to an embodiment of the present invention;
6 is a perspective view of a display device according to an embodiment of the present invention;
7 is a view illustrating a cathode, which is a common electrode of an AMOLED according to an embodiment of the present invention, is divided by a dot matrix method.
8 is a view illustrating a cathode, which is a common electrode of an AMOLED according to an embodiment of the present invention, is partitioned by a mesh method.
9 to 11 are diagrams illustrating a touch signal detection circuit diagram according to various embodiments of the present invention.
12 is a diagram illustrating a part of a touch signal operating unit according to an embodiment of the present invention;
13 is a circuit diagram showing an overcurrent limiting resistor according to an embodiment of the present invention.
14 is a diagram illustrating a configuration of an electronic device using a display device having a touch screen function according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings and embodiments. BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a display device having a touch screen function. For example, by detecting a touch signal using a common electrode of a display device, the display device performs an image display function As well as a touch function as a second function.

The display device referred to in the embodiment of the present invention uses a liquid crystal such as a VA (Vertical Alignment) series LCD, a TN series LCD, an IPS (In Plane Switching) or an FFS series transverse electric field mode LCD All LCDs can be included. It may also include all OLED (Organic Light Emitted Diode) displays such as PMOLED and AMOLED. And may also include any display means for displaying any type of still picture (e.g., JPG, TIF, etc.) or moving picture (MPEG2, MPEG-4, etc.).

The touch sensing sensor and the touch sensor referred to in the embodiment of the present invention can be used in the same meaning and the driving signal line of the touch sensor originating from the touch sensor and connected to the touch drive IC (TDI) As the sensor signal line or the sensor signal line, the touch sensor signal line and the sensor signal line may be used in the same sense.

The touch driver IC referred to in the embodiment of the present invention can be reduced to TDI, and the TDI can be included in a Touch Display Driver IC (TDDI). The TDDI includes a TDI and a DDI (Display Drive IC), and may be composed of one IC.

The term " in-line phase " referred to in the embodiment of the present invention can be used to mean that it is overlapped at the same upper and lower positions, and a metal material or an insulator or the like constituting a signal line or the like may be present therebetween. If A and B are on the same line, A may be on the top surface of B, or B may be on the top surface of A, and there may be an insulator or other material such as metal between A and B .

When A and B are on the same line, the width of A and the width of B are not limited unless otherwise specified, and the ratio of the widths of A and B Unless otherwise specified. However, as an embodiment of the present invention, the width of A and the width of B can be regarded as being the same.

The configurations such as " to " referred to in the embodiments of the present invention may be a collection of unit function elements performing specific functions. For example, an amplifier of a signal is a unit functional element, and an aggregate in which amplifiers and signal converters are gathered can be called a signal conversion unit. Also, " part " may be included in a larger element or " part, " or may include smaller elements and " parts. &Quot; The " part " may include a unique CPU (Central Processing Unit) capable of processing an operation function, a command stored in a memory, and the like.

In the drawings of the embodiments of the present invention, the thickness or area is enlarged in order to clearly illustrate various layers and regions. Like numbers refer to like parts throughout the various embodiments of the present invention. For example, when a portion of a layer, region, substrate, or the like is referred to as being "on" or "over" another portion, it is not only the case that there is another portion "just above" (E.g., an intermediate layer or an insulting layer) on the substrate.

The " signal " mentioned in the embodiment of the present invention may be collectively referred to as a voltage or a current unless otherwise specified, and the term " capacitance " refers to a physical size, Quot; capacitor " may be used to mean an element having a capacitance that is a physical size.

In the embodiment of the present invention, C, which is a symbol used as a symbol of a capacitor, is used as a code to designate a capacitor, and it can represent a capacitance which is a size of a capacitor. For example, C1 is a code indicating a first capacitor, which may be a capacitance of the first capacitor.

In the embodiment of the present invention, the term " forcing "means that the level of a signal in which a certain state is maintained may be changed. For example, the meaning of applying a signal to the on / off control terminal of the switching element is that a conventional low level voltage (e.g., a zero voltage or a constant size DC voltage or AC voltage) To a high (Hi) level (e.g., a DC voltage or an AC voltage having a larger amplitude value than the low level voltage).

In the embodiment of the present invention, the touch sensor participating in the touch signal detection may be referred to as a sensing pad and the non-participating touch sensor may be referred to as a non-sensing pad. May include both a sensing pad and a non-sensing pad.

The sensing pad is a touch sensor connected to the touch detection unit 14 for touch detection among a plurality of touch sensors. The non-touch sensing pad is a touch sensor that does not perform touch detection and is not connected to the touch detection unit 14. [ Lt; / RTI > The sensing pad becomes a non-sensing pad after the touch detection is completed, and any non-sensing pad can be switched to a sensing pad according to a predetermined sequence.

The sensing pad and the non-sensing pad are not fixed but can be converted over time, and the conversion order of each sensing pad and the non-sensing pad can be sequentially determined in a predetermined order. Here, a Time Sharing Technique can be used as one embodiment to set the order.

A pre-charge voltage applied to the sensing pad is referred to as a " first voltage " when the touch signal is detected, and a voltage applied to a non-sensing pad not detecting the touch signal is referred to as a & "

In an embodiment of the present invention, " detect touch " or " detect touch signal " may have the same meaning. A representative example of the touch signal detection is one in which a voltage detected by the touch detection unit 14 and a conductor such as a finger or the like are detected by the touch sensor 14 when a touch capacitance is not formed due to a conductor such as a finger touching or approaching the touch sensor, It may mean that the difference between the voltages detected by the touch detecting unit 14 is recognized by the touch capacitance Ct formed at the time of facing.

In the embodiment of the present invention, the pre-charge and charge can be used in the same meaning as the pre-charge voltage and the charge voltage. The sensing pad may include a sensor signal line connecting the sensing pad, and the non-sensing pad may include a non-sensing pad signal line connecting the non-sensing pad, unless otherwise specified in the embodiment of the present invention It can be meaningful.

In an embodiment of the present invention, a source line and a gate line may be collectively referred to as a signal line, and the signal line may refer to only a source signal line or a gate signal line. Also, in the embodiment of the present invention, a pixel can be used independently of a sub pixel.

Various embodiments of the driving unit 31 including the touch detection unit 14 or the touch detection unit 14 of FIG. 1 are described below with reference to FIGS. 9 to 11, Buffer is specified. The buffer is a means for making the touch sensor high impedance and may include any means in which the input is high impedance (Hi-z), such as the gate input of a MOS or the input of an OPAMP.

A sample and holder (S & H), a digital to analog converter (DAC), a programmable gain array (PGA), an analog to digital converter (ADC), a differential amplifier or various amplifiers and a comparator are connected to the output terminal of the buffer , For example, the elements can be sequentially interconnected.

1 is a diagram illustrating a touch screen according to an embodiment of the present invention.

Referring to FIG. 1, the touch screen may include a plurality of touch sensors 10, a sensor signal line 22, and the like. The touch signal detected by the touch screen is extracted in the form of coordinates in the touch signal operating unit 30 shown in FIG. 1, and is transmitted to a host requiring the extracted touch signal. Here, the transmission operation may be performed through the communication unit 46.

The touch signal operation unit 30 includes a touch detection unit 14, a signal processing unit 35, a memory unit 28, a power supply unit 47, a CPU 40, a timing control unit 33, A communication unit 46, a driving unit 31, and the like. Here, the touch detection unit 14 may be included in the driving unit 31.

The driving unit 31 may include a multiplexer and a part of the driving unit 31 may be included in a display device and the multiplexer may include a driving unit 31, Device. For example, the multiplexer may perform a multiplexing function to select one of the plurality of touch sensors 10. [

The driving unit 31 may be configured to isolate the touch sensor 10 in a high impedance state or to apply a pre-charge voltage or to apply the alternating voltage generated in the alternating voltage generating unit 42 And may output a change in voltage after a predetermined time elapses.

The signal processing unit 35 may receive and amplify or process the signal output from the driving unit 31 and the signal processing unit 35 may include an ADC, a DAC, or a comparator.

The memory unit 28 may temporarily store the results calculated by the signal processing unit 35 or may store firmware necessary for the operation of the CPU 40. [ The power supply unit 47 generates and supplies power to the touch screen or the touch signal operation unit 30.

The CPU 40 calculates touch coordinates based on the signal processed by the signal processing unit 35 or controls each component included in the touch signal operation unit 30, 33 generates a clock of a frequency required by the touch signal operation unit 30. [ The alternating voltage generating unit 42 generates an alternating voltage necessary for touch detection and may be included in the power unit 47. [

Referring to FIG. 1, the touch sensor 10 may be arranged in a 6 × 5 dot matrix manner, for example, consisting of six rows in the transverse direction and five columns in the longitudinal direction. The 6 x 5 dot matrix may be a dot matrix of various matrices such as 20 x 20 or 24 x 30 in practice as an example of the present invention.

In the embodiment of the present invention, in order to detect the touch, it is preferable that the sensor signal line 22 is arranged in a direction perpendicular to the sensor signal line 22 (e.g., in the lateral direction in FIG. 1), that is, Row1-> Row2-> Row3-> -> Row1 -> ... to detect a touch signal by applying a signal necessary for touch detection. For example, only Row1, Col1, Row1, Col2, Row1, Col3, Row1, Col4, and (Row1, Col5) are selected by the mux included in the driving unit 31, And may be electrically connected to the driving unit 31.

2 is a diagram illustrating a dot matrix type touch screen according to an embodiment of the present invention.

2, the touch screen may be, for example, a dot matrix type. In the driving unit 31 of FIG. 1, a multiplexer (hereinafter referred to as Mux) is included, And the mux may serve to select any one of the plurality of touch sensors 10 included in one column. Here, the mux may be included outside the driving unit 31, but the present invention is not limited thereto.

For example, the touch sensors are arranged in the form of a dot matrix having a plurality of rows and a plurality of columns, and one of the mips selects one of the sensor signal lines connected to the touch sensors belonging to one column Or may select any one of the sensor signal lines connected to the touch sensors belonging to at least two columns and connect the touch sensor to the touch detection unit.

The mips connected to the sensor signal lines as described above can be manufactured by the same mask in the process of manufacturing the mips connected to the source signal lines of the display device.

3 is a view illustrating an organic light emitting diode according to an embodiment of the present invention.

Referring to FIG. 3, the display device of the organic light emitting diode may have a plurality of organic light emitting diodes. The organic light emitting diode may include an organic compound layer formed between an anode electrode and a cathode electrode.

The organic compound layer may include a hole injection layer (HIL), a hole transport layer (HTL), an emission layer (EML), an electron transport layer (ETL) Injection layer (EIL).

When a drive voltage is applied to the anode electrode and the cathode electrode, holes passing through the HTL and electrons passing through the ETL are transferred to the EML to form an exciton, As a result, the light emitting layer (EML) generates visible light.

The display device of the organic light emitting diode arranges the pixels including the organic light emitting diode in a matrix form and controls the brightness of the pixels selected by the scan pulse according to the gradation of the digital video data.

The display device of the organic light emitting diode may be classified into a passive matrix (PMOLED) method and an active matrix (AMOLED) method using a TFT as a switching element. In the active matrix method, a pixel is selected by selectively turning on a TFT as an active element, and light emission of a pixel can be maintained at a voltage held in a storage capacitor (Cst).

4 is a circuit diagram illustrating a pixel according to an embodiment of the present invention.

Referring to FIG. 4, for example, in a display device of an active matrix type organic light emitting diode, a pixel includes an organic light emitting diode OLED, a data line D and a gate line G intersecting with each other, And a storage capacitor Cst for storing data and holding data for a predetermined period of time, and the like.

The scan switch SW and the drive switch DR may be either N-type or P-type MOS-FETs. The structure consisting of the two transistors SW and DR and one capacitor Cst can be referred to as a 2T-1C structure.

The scan switch SW is turned on in response to the scan pulse SP of the gate line G to thereby conduct a current path between the source electrode and the drain electrode of the scan switch SW. During the on time period of the scan switch SW, the data voltage of the data line D is applied to the gate electrode of the drive switch DR through the source electrode and the drain electrode of the scan switch SW, And is applied to the storage capacitor Cst.

The driving switch DR controls a current flowing in the organic light emitting diode OLED in response to a difference voltage Vgs between its gate electrode and a source electrode. The storage capacitor Cst stores a data voltage applied to one electrode of the storage capacitor Cst so that the voltage supplied to the gate electrode of the drive switch DR is maintained constant for one frame period.

The organic light emitting diode OLED of FIG. 3 is connected between a source electrode of the drive switch DR and a drive voltage source ELVSS of low voltage. The current flowing through the organic light emitting diode OLED is proportional to the brightness of the pixel and is determined by the voltage between the gate and the source of the driving switch DR. Here, the three subpixels shown in FIG. 4 share one ELVSS, and correspond to the cathodes of FIG.

5 is a perspective view illustrating a pixel according to an exemplary embodiment of the present invention.

5, a drive switch DR, gate signal lines G1 to G3 of the drive switch DR, and ELVDD of the drive switch DR are shown on an upper surface of a substrate (not shown) . Also shown is an organic emitter. Here, the organic light emitting element corresponds to the organic compound layer in FIG. 3, and the scan switch SW is omitted in FIG.

Data voltages applied from the data lines D1 to D3 are applied to the gates G1 to G3 of the driving switch DR by the turn-on of the scan switch SW. The gates (G1 to G3) of the drive switch DR are separated from each other and connected to a scan switch (not shown), respectively.

Referring to FIGS. 4 and 5, a cathode layer is connected to all pixels, which is shared by all the pixels, and is called a common electrode. The common electrode of the AMOED is structurally similar and functionally similar to the common voltage of the TN series LCD or the IPS series LCD.

The structural similarity is that the common electrode of the AMOLED and the common electrode of the LCD are vertically or horizontally opposed to all pixels in common. In the TN series LCD, the common electrode is opposed to the top and bottom of the pixel, and in the IPS series, the common electrode is opposed to the left or right or up and down.

The functional similarity is that the same voltage is applied to the common electrode of the AMOLED and the LCD. For example, a common voltage of some LCD is -2V applied to all the common electrodes, and -5.4V is commonly applied to the cathode common electrode of some AMOLEDs.

Therefore, although the common electrode of the cathode of the AMOLED is described as an example in the present invention, the technical idea of the present invention can be similarly applied to an LCD. In other words, in the embodiment of the present invention, an example of an apparatus and method for detecting a touch signal using a common electrode of an AMOLED is described as an example, but the technical idea of the present invention is also applicable to an LCD have.

6 is a perspective view of a display device according to an embodiment of the present invention.

6, the display device may include a display area DA, a non-display area (NDA), and a pixel area (PA) The pixel region PA of the display region DA can form the screen display region DA.

On the top surface of Fig. 6, the cathode may be provided so as to form a common electrode and face all the pixels. That is, a cathode of one layer is commonly connected to all the pixels or subpixels to supply the ELVSS of FIG. 4, and the cathode of FIG. 6 includes an ELVSS supplied by the DDI for AMOLED at an arbitrary point Can be connected.

FIG. 7 is a view illustrating a cathode, which is a common electrode of an AMOLED according to an embodiment of the present invention, by a dot matrix method.

Referring to FIG. 7, a pixel area PA is included in a screen display area DA of a display device, and one cathode partitioned to face a plurality of pixels serves as a touch sensor 10.

The sensor signal line 22 connected to the touch sensor 10 is connected to the touch signal processor 30 and the sensor signal line 22 connected to the driver 31 of the touch signal processor 30 A cathode voltage ELVSS which is a voltage may be applied, or a pre-charge voltage for touch detection, or an alternating AC voltage may be applied.

The cathode, which is the common electrode, is divided into a plurality of parts, and one separated cathode serves as the touch sensor 10, serves as a common electrode of the display device, and performs two functions at the same time. When the two functions are simultaneously performed, a common voltage of the display device is applied to the sensing pad and the non-sensing pad of the touch sensor.

When the separated cathode serves as the touch sensor 10, the cathode may not function as a common electrode. In this case, the pre-charge voltage required for touch detection is applied to the touch sensor 10 instead of the cathode voltage ELVSS, and the pre-charge voltage may be different from the cathode voltage.

The sensor signal line 22 connected to the touch sensor 10 may be formed at the same time as a transparent conductive material such as ITO or IZO constituting the touch sensor 10 by a mask forming the touch sensor.

The sensor signal line 22 may be formed of a non-permeable metal material such as silver (Ag) or copper or aluminum and may be formed separately from the mask forming the touch sensor 10, And may be located at an upper layer or a lower layer of the touch sensor 10. [

The one touch sensor 10 may include one or a plurality of pixels. A plurality of pixels included in the pixel area PA of FIG. 7 may be included in the touch sensor by one common electrode, and all the touch sensors 10 may include a plurality of pixels.

Since the touch sensor 10 serves as a cathode which is a common electrode of the AMOLED, a cathode voltage ELVSS, which is a common voltage, is used to detect a touch signal or to act as a display device when the touch signal is not detected Is preferably applied. Here, the potential of the cathode voltage is preferably the same. For example, the same -5.4 V can be applied to all touch sensors serving as cathodes.

If a voltage applied to the touch sensor 10, which is a sensing pad when detecting a touch signal, is different from a common voltage, a non-sensing pad that does not detect a touch signal includes a cathode voltage (ELVSS) must be applied. Therefore, in the area where the touch is not detected, the screen of the display device is normally displayed.

FIG. 8 is an exemplary view illustrating a cathode, which is a common electrode of the AMOLED according to an embodiment of the present invention, in a mesh manner.

Referring to Fig. 8, in the screen display area DA, there are displayed a plurality of pixels, one pixel is displayed as PA, and touch sensors 10a to 10d serving as common electrodes are displayed.

In one embodiment, the touch sensor may be partitioned into various combinations, such as a matrix of 10 x 10 matrix or a matrix of 20 x 20 matrix. The above structure can be applied to a common electrode of an LCD having a transverse electric field mode (IPS system) or a TN mode in addition to a common electrode of an AMOLED.

On one side of the display region, there is a data signal line (Data Line) or a source signal line, and there is a gate signal line (Gate Line) crossing the data signal line. The data signal line or the gate signal line may correspond to a BM (Black Matrix) area in which a screen is not displayed. Here, the BM region may be a region corresponding to or included in a boundary region between a pixel and a pixel, and may be referred to as any other name.

It is already described that one cathode shown in Fig. 5 or 6 is divided into a plurality of cathodes and operated as a common electrode and a touch sensor, as in Fig. The divided touch sensor 10 includes a plurality of pixels and also operates as a common electrode, so that the common voltage ELVSS may be applied.

Since the partitioned touch sensor 10 simultaneously serves as a common electrode, the partitioned touch sensor must be opposed to or vertically opposed to the pixel in the partition portion, so that there is no pixel not included in the touch sensor do.

For this purpose, when dividing a common electrode, a boundary portion between a pixel and a pixel, that is, a BM region such as a data line or a gate line, is defined as a boundary. A data signal line is provided at the boundary between the touch sensors 10a and 10b shown in Fig. 8, and all the pixels are included in the touch sensors 10a and 10b when they are adjacent to the data signal line. And may be partitioned from 0.1um to 20um based on the center of the data signal line.

In addition, all the pixels are included in the touch sensors 10a and 10c when the touch sensors 10a and 10c are provided with gate lines and the touch sensor is divided as close as possible to the gate line. Preferably, the distance from the center of the gate signal line is 0.1 mu m to 20 mu m. As described above, in the embodiment of the present invention, when the common electrode is partitioned, it can be partitioned around the data line or the gate line.

On the other hand, the sensor signal line 22 shown in Fig. 8 can be located on the upper side or the lower side of the BM region, and can be positioned in opposition to the pixel to serve as a common electrode. The sensor signal lines 22a to 22d shown in FIG. 8 are provided opposite to the upper side of the pixel, but they may be provided on the lower side. The sensor signal lines 22a to 22d may perform signal transmission for detecting a touch signal and serve as a common electrode, It is also possible to serve as a cathode.

Although the sensor signal line 22 shown in FIG. 8 has been described as being opposed to one pixel, it is also possible to oppose a plurality of pixels. Also, the sensor signal line 22 is divided into a plurality of The partitioning method of the touch sensor according to the embodiment can be applied equally.

9 to 11 are diagrams illustrating a touch signal detection circuit diagram according to various embodiments of the present invention.

9, the touch sensor 10 formed of one of the divided common electrodes of the display device is connected to the driving unit 31 of the touch sensor operation unit 30. [ 9 to 11 illustrate a touch detection unit 14 included in the touch sensor operation unit 30. The touch detection unit 14 may be included in the drive unit 31 or may include the drive unit 31, It may be a separate configuration to be interlocked.

The touch sensor 10 is connected to a touch detection unit 14. The touch detection unit includes a switch SW for applying a precharge voltage Vpre, a buffer, and an amplifier, ADC or DAC And the like.

One side of the parasitic capacitance Cp is connected to one side of the touch sensor 10 and the parasitic capacitance is set to a parasitic capacitance between the sensor signal lines 22 or layout of the corresponding wiring in the TDI or TDDI. The parasitic capacitance generated between the cathode and the anode, or the parasitic capacitance (Clc) generated due to the liquid crystal.

The precharge voltage is applied to the touch sensor 10 and the switch SW turned on when the precharge voltage is applied is turned off after the precharge voltage is applied. Thereby maintaining the touch sensor 10 in a high impedance state.

1. First, regarding touch signal detection Example

9 is a circuit diagram of the first embodiment relating to touch signal detection. A method of applying an alternating driving voltage to one side of a touch sensor and a driving capacitor Cdrv connected to one side of the touch sensor may be applied. The driving capacitor Cdrv may be formed inside the TDI or TDDI.

In the first embodiment, when the switch is turned on, the pre-charge voltage is applied, and the switch is turned off, the touch sensor 10 is in a high impedance state. At this time, A voltage is detected in the buffer, and the voltage detected at this time has a correlation with the magnitude of the touch capacitor or the touch capacitance Ct.

The touch capacitance Ct is determined by the touch input means such as a finger or the like and the distance d and the opposing area S between the touch sensor 10 and the complex electrostatic charge of the materials filled between the touch input means and the touch sensor It is determined by capacity. That is, it is determined by the formula Ct = e (S / d), where e is the permittivity.

In the touch detection unit 14, it is possible to determine the magnitude of Ct using this voltage difference, and calculate touch coordinates. The CPU 40 can take charge of calculating the touch coordinates.

2. The second Example

Fig. 10 is a circuit diagram of a second embodiment relating to touch signal detection. In Fig. 10, a method of applying an alternating driving voltage to one side of one or a plurality of nonsensifying pads 10a and 10c adjacent to the sensing pad 10b Can be applied.

In the second embodiment, the touch signal can be detected based on the parasitic capacitors between lines formed between the signal lines 22a and 22c of the non-sensing pad and the signal line 22b of the sensing pad. A voltage having a correlation with the magnitude of the touch capacitance Ct is output to the buffer of Fig. 10, and the CPU 40 can calculate coordinates using the magnitude of the output voltage.

3. Touch signal detection Third Example

11 is a circuit diagram of a third embodiment relating to touch signal detection. In the touch detecting section 14 including a switch to which a pre-charge voltage is applied, a buffer or an invisible amplifier, an ADC or a DAC, A voltage having a correlation with the magnitude of the touch capacitance Ct can be detected in the buffer.

In the third embodiment, the DGND is an alternating ground, and the potential difference between DGND and Vci is 3 V or 5 V when the DGND and Vci have a potential difference of 3 V or 5 V. When the DGND alternates to 10 V, And Vci are in the form of alternating voltages at 10V.

In the first to third embodiments, the pre-charge voltage is applied to the common electrode 10 serving as a touch sensor. Here, the pre-charge voltage can be applied with a cathode voltage (ELVSS) which is a common voltage, and when a common voltage is applied to the non-sensing pad, it is possible to normally display the screen of the touch signal detection and display device.

On the other hand, in the first to third embodiments, when the pre-charge voltage can not be applied as the common voltage ELVSS, a common voltage is applied only to the non-sensing pad, , It is possible to detect the touch signal and to display the screen on the display device. The time division method will be described with reference to FIG. 8 as an example.

The touch signal detection and screen display method according to the embodiment of the present invention is a method of displaying a screen on a display device after detecting a touch signal. For example, in FIG. 8, one touch sensor includes five gate signal lines. Since the time for detecting the touch using the touch sensor 10 is only several tens us, it is possible to detect the touch signal by one touch sensor 10 and then sequentially transmit the gate signal line included in the touch sensor 10 Can be used to display the screen. The above method can be equally applied to the lower stage. Here, it is necessary that the above-described method has a predetermined regularity such as proceeding from the top to the bottom of the screen display area DA or going from the bottom to the top.

Accordingly, the touch signal is detected in a short time, the damaged screen is quickly refreshed due to the touch signal detection, and at least the user can not recognize the screen abnormality, thereby enabling both the touch detection and the screen display. The method can be achieved by use of a frame memory for storing image information or a line memory for storing image information on a plurality of lines.

12 is a diagram illustrating a portion of a touch signal operating unit according to an embodiment of the present invention.

12, a mux included in one column, a selection signal sel for controlling the mux, a control signal, and the like will be described in detail.

According to an embodiment of the present invention, one mux may be installed in one column, and the mux selects one of the plurality of touch sensors 10 to connect to a driving unit 31 including a buffer. The driving unit 31 includes the touch detection unit 14 or is interlocked with the touch detection unit 14 and the touch detection unit 14 is connected to one touch sensor selected by the mux.

One touch sensor 10 selected through the mux is a sensing pad for detecting a touch signal and the other is a non-sensing pad for not detecting a touch signal. The MUX of FIG. 12 is generally present inside the TDI or TDDI. Referring to FIG. 2, when there are 30 touch sensors 10, 30 input terminals are required for the TDDI if the mux is located inside the TDDI. If there are hundreds of the touch sensors 10, The number of input terminals of the TDDI must be several hundreds, so that the volume of the TDDI is increased and the price is increased.

In order to solve this problem, in the embodiment of the present invention, the mux may be installed on one side of the display device. For example, if the mux of FIG. 2 is installed in the display device and only one output of the mux is input to the touch IC, TDI or TDDI, the 30 input terminals are reduced to only five, Reduction and so on.

The touch IC or the TDDI is essentially separate from the display device and can be electrically connected to the display device using a material such as a COG (Chip On Glass) package and an ACF (Anisotropic Conductive Film).

The above-mentioned mux will be described in detail as follows. In recent years, due to the stabilization of the LTPS process, a mux for driving a plurality of pixels in a time-division manner as one source signal line for driving a display device such as an LCD or an AMOLED is widely used.

Since the above-mentioned mux has proved its usefulness, there is no problem to introduce it into the touch signal detection. The advantage of this technique is that when designing and manufacturing the mux necessary for driving the display, the mux for touch can be designed and manufactured together at the same time, which means that the cost is reduced.

As described above, the MUX manufactured for the touch may be installed on one side of the display device of the LCD or AMOLED. For example, it may be installed in a non-display area of FIG. 6, and may be installed at a position similar to a mux for screen display.

According to the embodiment of the present invention, a plurality of touch sensors 10 located in the same column are connected to one mux. Here, the term " same column "means a group in which the sensor signal line 22 is bundled down into a harness as described above with reference to FIG.

Since a plurality of touch sensors are connected to the one mux and only one of them is selected, a selection signal (select) for selecting one of the plurality of touch sensors is required for the mux, It is specified as "sel" in 12.

Since a common voltage (ELVSS) of the AMOLED or a common voltage for the LCD must be applied to a non-selected sensing pad other than the sensing pad selected by the MUX, a control signal for applying such a voltage and a voltage required therefor are required. In Fig. 12, a control signal for applying a voltage is specified as " control ", and a required voltage such as the common voltage is specified as "required voltage ".

The selection signal sel, the control signal, and the " required voltage " can be designed and manufactured using a TFT (Thin Film Transistor) process of a display device, but can be designed and manufactured by a touch IC such as TDDI or TDI . This is because when the TFT is used, the display device has a narrow space to generate it, and the operation speed of the TFT is slow, so that it is difficult to drive to a desired frequency band.

Therefore, in the embodiment of the present invention, one touch sensor 10 is provided from the mux provided on one side of the display device. The above-mentioned mux can be manufactured through the same process with the same mask in the process of manufacturing the mux connected with the source line of the display device.

The mux may include both N-type or P-type or PN-type CMOS types. A selection signal, a control signal, and a necessary voltage, which are generated from the touch IC, are supplied to the mux. The selection signal, the control signal, and the required voltage originating from the touch IC can be individually supplied to all the muxes. For example, five groups of select signals and five groups of control signals are supplied to five muxes.

However, this is inefficient because the touch IC requires a large number of output terminals. Therefore, it is preferable that only one group originates from the touch IC and is branched in the display device.

5, since the process of manufacturing the TFT (i.e., the process of manufacturing the mux) precedes or follows the common electrode, the common electrode (particularly the cathode of the AMOLED) and the mux are located on different layers can do. For example, the muxes located on different layers and the sensor signal lines using the common electrode can be electrically connected through the contact holes. For this purpose, a contact mask is used, And the divided common electrodes can be electrically connected to each other.

Although an example is given for connecting the common electrode partitioned in the embodiment of the present invention and the mux embedded in the display device, more embodiments are possible. For example, even when a touch sensor as shown in Fig. 1 is formed on a separately formed layer on the top surface of the cathode which is the common electrode of Fig. 5, the touch sensor can be connected to the mux built in the display device, Or a mesh type touch sensor provided so as to face downward can be connected to the mux even when the touch sensor is provided on the upper surface of the cathode of the AMOLED or on the upper or lower side of the BM region of the LCD.

The mesh-type touch sensor may be made of metal, or may be made of a transparent conductive material such as ITO. For example, the case of metal is referred to as a metal mesh. Meanwhile, the touch sensor may have various shapes such as a rectangular shape as well as a diamond shape.

In the second embodiment of FIG. 10, the voltage sensing electrodes to which the alternating voltage is applied are applied with alternating voltages in the display device, and the touch signals of the sensing pad are detected based on the alternating voltages.

According to the embodiment of the present invention, when a plurality of columns are connected to one mux, the number of sensing pads input to the touch IC will be further reduced. For example, there is a terminal that simultaneously connects the mux of FIG. 12 to col1 and col2, and the control signal (control) designates an odd column and an even column. When the odd column is activated, One sensing pad is output from the mux, and when the column is activated, the sensing pad in col 2 will be output from the mux and connected to the touch IC.

Therefore, it is possible to provide a technique of connecting a plurality of columns to one mux and dividing them into control signals, thereby reducing the number of terminals input to the touch IC, thereby further securing price competitiveness of the touch IC It is possible.

Since the sensing pad 10 plays a role of a common electrode of a display device, when the gradation voltage relating to the screen data is written to the pixel in order to display the screen on the pixels of the AMOLED or the LCD, There is a possibility that a large amount of instantaneous current flows and the sensor signal line 22 is open.

13 is a circuit diagram showing an overcurrent limiting resistor according to an embodiment of the present invention.

Referring to FIG. 13, a resistor R for current limitation is inserted into one side of the touch sensor 10. The resistor may be connected to one side of all the touch sensors 10 and installed in the display device when the mux is installed in the display device. For example, the resistor may be connected to the touch sensor before the input of the mux.

When the mux is formed inside the touch IC, a resistance can be formed inside the touch IC. When a resistance is formed in the display device, the resistance is formed by a turn-on resistance of the TFT .

The operation of the resistor will now be described. It is reported that an overcurrent flows in the touch sensor 10 serving as a common voltage to be connected to the pixel when writing the screen data to the pixel, at the beginning of data writing.

Therefore, the control signal (cont) originating from the touch IC receives a signal for writing data on the screen from the DDI, or when it is TDDI, knows the time when it writes data on the screen, Is a Hsync or DE signal) turns on or off the switch SW.

For example, the switch SW will be turned off at this time because an overcurrent flows within an initial number us of writing data on the screen. As a result, the current is limited through the resistor connected to the common electrode, so that the open of the sensor signal line 22 due to the overcurrent does not occur. Also, after the number of us, the touch IC or the TDDI causes a current to flow through the switch when the switch SW is turned on, so that a normal current for the pixel data will flow if the turn-on resistance of the switch is small.

Such an effect would be better for AMOLED. Since there is a parasitic capacitor between the anode and the cathode of the AMOLED, and one touch sensor generally includes hundreds of pixels, an overcurrent instantaneously flows, and the resulting disconnection of the sensor signal line 22 is more likely to occur .

However, in the embodiment of the present invention in which the role of the common electrode as the cathode and the role as the touch sensor are combined, it is possible to prevent the overcurrent by combining the resistor and the switch in parallel on one side of the touch sensor.

It is also possible to limit the overcurrent by applying various embodiments such as the overcurrent limiting method due to the TFT circuit or the overcurrent limiting method due to the MOS as an embodiment of the overcurrent limiting.

FIG. 14 is a diagram illustrating a configuration of an electronic device using a display device having a touch screen function according to an embodiment of the present invention.

The display device having the touch screen function according to the embodiment of the present invention can be included in various types of electronic devices such as a smart phone, a PDA, a PMP, a navigation, a netbook, a notebook, a DID, a desktop computer, and an IP TV.

14, an electronic device 1400, such as a smart phone, for example, includes a control unit 1410, a touch screen 1420, an audio processing unit 1430, an interface unit 1440, a communication unit 1450, A storage unit 1460, and the like. Here, the touch screen may refer to a display device having a touch screen function of the embodiment of the present invention.

The controller 1410 may be a processor or a controller that performs an overall operation or control of the electronic device in cooperation with the touch screen 1420.

According to the embodiment of the present invention, the controller 1410 may perform an operation corresponding to the touch detected by the touch screen 1420 in conjunction with the touch screen 1420, as described above.

For example, the controller 1410 can perform an operation corresponding to the position of the touch when the touch of the touch input means is accessed or touched, for example, on the touch screen.

For example, the operation may be various control operations, such as volume control, power control, and reset control, which are set in advance in order to control at least one of the functions of the electronic device.

The embodiments of the present invention described in detail above may be implemented individually or in combination with each other. The present invention described above is not limited to the above-described embodiment and the accompanying drawings, and various substitutions, modifications and variations are possible without departing from the technical spirit of the present invention. Which will be apparent to those skilled in the art to which the present invention pertains.

10: touch sensor 14: touch detection unit
22: sensor signal line 28:
30: Touch signal computing unit 31:
33: timing control section 35: signal processing section
40: CPU 42: Alternating voltage generating section
46: communication unit 47:

Claims (26)

In a display device having a touch screen function,
Touch sensors for generating a touch signal;
Sensor signal lines connected to the touch sensors; And
And a touch detection unit that receives the touch signal through the sensor signal lines and detects at least one of touch and touch coordinates,
Wherein the touch sensors and the sensor signal lines are formed by separating a plurality of common electrodes of the display device.
The method according to claim 1,
The display device is an AMOLED display device,
Wherein the touch sensors and the sensor signal lines are formed by dividing a cathode, which is a common electrode of the AMOLED display device, into a plurality of electrodes.
3. The method of claim 2,
Wherein the plurality of separated cathodes selectively perform a role of the touch sensors and the sensor signal lines and a role of the common electrode.
3. The method of claim 2,
The touch sensors are divided into sensing pads during touch sensing and non-sensing pads during non-touch sensing,
Wherein a cathode voltage, which is a common voltage of the AMOLED display device, is applied to the sensing pads and the non-sensing pads.
5. The method of claim 4,
Wherein when the voltage applied to the sensing pads is different from the cathode voltage, the cathode voltage is applied to the non-sensing pads.
The method according to claim 1,
Wherein the sensor signal lines are formed by the same material and mask that constitute the touch sensors.
The method according to claim 1,
Wherein the common electrode is divided based on a boundary region between the pixel and the pixel.
8. The method of claim 7,
Wherein the sensor signal lines are located on the upper or lower side of the boundary region or on the upper side or the lower side of the pixel.
The method according to claim 1,
Wherein the touch sensors and the sensor signal lines are opposed to at least one pixel.
The method according to claim 1,
Wherein the touch sensors are arranged in the form of a dot matrix having a plurality of rows and a plurality of columns.
The method according to claim 1,
An overcurrent limiting circuit is provided on one side of the touch sensors,
Wherein the overcurrent limiting circuit includes a resistor and a switch.
The method according to claim 1,
Wherein the touch sensors are formed in a mesh pattern composed of a transparent conductive material or a non-transparent metal material, and are arranged in a shape of at least one of a rectangle or a rhombus.
The method according to claim 1,
Wherein the touch detection unit is any one of a touch drive IC, a display drive IC, or a touch display drive IC in which the touch drive IC and the display drive IC are integrated.
The method according to claim 1,
Wherein the touch detection unit detects a touch signal based on the touch sensors and a touch capacitor (Ct) obtained by applying an alternating voltage to a driving capacitor (Cdrv) connected to one side of the touch sensors A display device having a screen function.
The method according to claim 1,
The touch detection unit includes: A touch capacitor (Ct) obtained by applying an alternating voltage to one side of one or more non-touching non-touch sensing pads adjacent to the upper or lower side of the touch sensing pads of the touch sensors; And a touch signal is detected based on an inter-parasitic capacitor (Cp) formed between sensor signal lines of the sensing pads.
The method according to claim 1,
The touch detection unit includes: A touch signal is detected based on the touch sensors and a touch capacitor Ct obtained by applying an alternating voltage to a parasitic capacitor Cp connected to one side of the touch sensors, And an alternating voltage having a predetermined voltage is applied to the display panel.
In a display device having a touch screen function,
Touch sensors for generating a touch signal;
Sensor signal lines connected to the touch sensors;
Mips connected to the sensor signal lines; And
And a touch detection unit receiving the touch signal through the mips and detecting at least one of a touch state and a touch coordinate system,
Wherein the touch sensors and the sensor signal lines are formed by separating a plurality of common electrodes of the display device.
18. The method of claim 17,
The touch sensors are arranged in the form of a dot matrix having a plurality of rows and a plurality of columns,
Wherein one of the muxes selects one of the sensor signal lines connected to the touch sensors belonging to one column or selects any one of the sensor signal lines connected to the touch sensors belonging to at least two columns, Wherein the display unit is connected to the touch detection unit.
18. The method of claim 17,
Wherein the mips connected to the sensor signal lines are manufactured by the same mask in the process of manufacturing the mips connected to the source signal lines of the display device.
18. The method of claim 17,
And the mips are electrically connected to the sensor signal lines through a contact hole.
18. The method of claim 17,
Wherein the muxes receive at least one of a selection signal, a control signal, and a required voltage output from the touch detection unit.
18. The method of claim 17,
The touch sensors are divided into sensing pads during touch sensing and non-sensing pads during non-touch sensing,
Wherein the muxes select sensor signal lines connected to the sensing pads.
23. The method of claim 22,
A common voltage or alternating voltage is applied to the non-sensing pads connected to the muxes,
Wherein the touch detection unit detects a touch signal of the sensing pads based on the common voltage or the alternating voltage.
18. The method of claim 17,
An overcurrent limiting circuit is provided on one side of the touch sensors,
Wherein the overcurrent limiting circuit includes a resistor and a switch, and is installed on one side of the display device and before the input of the mugs.
In the electronic device,
A display device having a touch screen function; And
And a processor coupled to the display device,
The display device having the touch screen function includes:
Touch sensors for generating a touch signal;
Sensor signal lines connected to the touch sensors; And
And a touch detection unit that receives the touch signal through the sensor signal lines and detects at least one of touch and touch coordinates,
Wherein the touch sensors and the sensor signal lines are formed by separating a plurality of common electrodes of the display device.
26. The method of claim 25,
The electronic device may be at least one of a smart phone, a personal digital assistant (PDA), a portable multimedia player (PMP), a navigation device, a netbook, a notebook, a digital information device (DID), a desktop computer, .

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