KR20140094232A - Touch input system and method for detecting touch using the same - Google Patents

Abstract

The present invention relates to a touch input system and a touch detecting method using the same capable of discriminating a touch by a stylus pen, without a battery, and a finger to detect the discriminated touch and to further enhance sensitivity and correctness of the touch, wherein the touch input system comprises a touch sensor panel having a plurality of first channels and second channels crossing each other; the stylus pen including a first coil and a second coil split from each other, a resonance capacitor and a switch serially connected to the second coil, and a conductive tip connected to the first coil; a grounding part connected to the stylus pen; an antenna loop formed with a structure of multiple loops formed around the sensor panel; and a touch controller connected to the first channel, the second channel, and the antenna loop.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a touch input system and a touch detection method using the touch input system.

The present invention relates to a touch input system, and more particularly, to a touch input system and a touch detection method using the touch input system, in which a battery-free stylus pen and a touch by a finger can be separately detected and improved in touch sensitivity and accuracy will be.

Recently, the field of display that visually expresses electrical information signals has rapidly developed as the information age has come to a full-fledged information age. In response to this, various flat panel display devices (flat display devices) having excellent performance such as thinning, light- Display Device) is being developed.

Examples of the flat panel display device include a liquid crystal display device, a plasma display panel device, a field emission display device (FED), an organic light emitting diode display device (Organic Light Emitting Diode Display Device ) And the like.

In recent years, a touch panel capable of recognizing a touch area through a human hand or a separate input device and communicating additional information corresponding to the touch area has been added to the flat panel display. Currently, such a touch panel is applied to the outer surface of a display device. According to the touch sensing method, there are a resistance method, a capacitance method, an infrared sensing prevention, etc. Recently, a capacitance method has been attracting attention in consideration of convenience of manufacturing method and detection power.

As a mobile device to be considered mainly in recent years, smart phones, smart books, and the like are human interface devices (HIDs), which are used not only for touch input using a finger but also for a stylus pen capable of handwriting or drawing using a pen, to be. The stylus pen input has advantages such as more detailed input than the input by the finger, and the function of the detailed drawing and the writing of the writing.

However, in the case of the touch panel to which the same touch detection circuit is applied, the touch sensitivity of the stylus pen is lowered, and there is a problem that the touch by the finger and the touch by the stylus pen can not be distinguished. In other words, in the case of a general touch panel to which the same touch detection circuit is applied, it is difficult to detect a change in capacitance because the area of contact with the touch panel is small when the stylus pen is touched. As a result, the accuracy of coordinate extraction becomes poor, and it is difficult to have the function of palm rejection. A method of performing touch detection through a driving method different from that of the touch sensor panel touch, for example, a driving method of an electromagnetic type, has been disclosed. However, in this case, in addition to a separate electrostatic type electrode, It is necessary to further include a panel capable of detecting the above-mentioned problems.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems and it is an object of the present invention to provide a touch input system and a touch detection method using the touch input system, .

According to an aspect of the present invention, there is provided a touch input system including: a touch sensor panel having a plurality of first channels and a plurality of second channels intersecting with each other; A stylus pen including a primary coil and a secondary coil separated from each other, a resonant capacitor and a switch connected in series with the secondary coil, and a conductive tip connected to the primary coil; A grounding portion connected to the stylus pen; An antenna loop formed in a plurality of loop structures formed outside the sensor panel; And a touch controller connected to the first and second channels and the antenna loop.

Wherein the antenna loop of the plurality of loop structures receives the resonance inductance signal from the primary coil in the stylus pen when the touch sensor panel surface of the stylus pen is touched.

The antenna loop of the multiple loop structure is formed so as to surround the front outer surface of the touch sensor panel, and pads are provided on both ends of one side and the other side, respectively, and are connected to the touch controller.

Wherein the antenna loop of the plurality of loops has an inductance signal resonated from the secondary coil in the stylus pen when touching the touch sensor panel of the stylus pen to the antenna loop itself and the secondary coil- And receiving the mutual inductance inductance between the primary coils.

The touch controller includes: an amplifier connected to the antenna loop to amplify a voltage difference received across the antenna loop; A filter unit connected to the amplifier to remove noise; A converter connected to the filter unit to convert an analog signal into a digital signal; A signal processing unit connected to the converter to collect digital signals and extract coordinates; And a driving signal generator for generating a signal to be applied to each channel in the sensor panel.

According to another aspect of the present invention, there is provided a touch detection method using a touch input system including a sensor panel having a plurality of first and second channels intersecting with each other, And a resonance capacitor and a switch connected in series with the secondary coil, a stylus pen including a conductive tip connected to one end of the primary coil, and an antenna loop formed in a plurality of loop structures outside the sensor panel A touch detection method of an input system is characterized in that finger touch detection for each frame and stylus pen touch detection are time-divided.

Wherein the stylus pen touch detection is performed by sequentially applying a signal to the plurality of first and second channels and performing touch detection by a voltage difference received at both ends of the antenna loop of the plurality of loop structures .

The antenna loop of the multiple loop structure is formed so as to surround the front outer surface of the touch sensor panel, and pads are provided on both ends of one side and the other side, respectively, and are connected to the touch controller.

Wherein the touch detection includes electrical connection between the detection capacitor between the conductive tip and the sensor panel and the primary coil and the switch is closed to form a resonance circuit of the secondary coil and the resonance capacitor, And an electromagnetically resonant induced electromotive force is received by the antenna loop of the multiple loop structure by the mutual inductance between the secondary coils.

Wherein the touch detection by the touch controller comprises: detecting a voltage difference received at both ends of the antenna loop of the plurality of loop structures sequentially for the plurality of first and second channels; Amplifying the voltage difference; Removing noise of the amplified voltage difference; Converting the noise-removed amplified voltage difference from an analog signal to a digital signal; And storing the digital signal in a memory, wherein the step of detecting touch coordinates by calculating a digital signal stored in a memory for each of the plurality of first and second channels.

The touch input system of the present invention and the touch detection method using the touch input system have the following effects.

First, the basic structure is a touch sensing type of capacitive touch sensing for finger touch. Touch detection by stylus pen resonance circuit and resonance through antenna loop outside sensor panel Do. In other words, the stylus pen touch detection with the limitation of the touch detection by the capacitance type can be made without the influence of the shape of the contact area or the electrode pattern by changing the outer structure of the sensor panel and the internal circuit of the stylus pen without constituting a separate panel .

Second, the touch detection can be performed by the resonance action between the antenna loop of the sensor panel formed of a plurality of loop structures and the resonance circuit inside the stylus pen, so that there is no need to attach the battery to the inside of the stylus pen, The manufacturing cost of the stylus pen is reduced. In addition, it is possible to implement a stylus pen that is light and small in size.

Thirdly, the stylus pen touch and the finger touch can be distinguished from each other by different driving methods, so that palm rejection is facilitated in the case of the stylus pen touch, and the sensor panel antenna The accuracy of the touch sensitivity is improved by the loop.

Fourthly, the antenna loop formed by a plurality of loop structures used for touch detection by the stylus pen is spaced apart from the active area where the electrodes crossing each other are formed, and positioned outside the edge area where the sensitivity is deteriorated, Can be kept equal.

1 is a circuit diagram illustrating a touch input system according to an embodiment of the present invention;
FIG. 2 is a plan view showing the touch sensor panel shown in FIG. 1. FIG.
Fig. 3 is a circuit diagram showing a portion corresponding to the stylus pen of Fig. 1; Fig.
Fig. 4 is a structural view of the stylus pen of Fig. 3; Fig.
5 is a diagram illustrating a frame driving method of the touch input system of the present invention.
6 is a waveform diagram showing detection waveforms of the respective components of the touch sensor panel and the stylus pen.
Fig. 7 is another planar view showing the antenna loop of the multiple loop structure shown in Fig. 2; Fig.
8A to 8C are waveform diagrams showing input / output waveforms input / output to and from a loop pad according to the number of loops of the antenna loop according to the present invention, respectively.

Hereinafter, a touch input system and a touch detection method using the touch input system according to the present invention will be described in detail with reference to the accompanying drawings.

The touch input system according to the present invention uses a structure of capacitive touch detection with respect to a finger touch as a basic configuration. When detecting the touch of the battery-free stylus pen, It is possible to perform touch detection by resonance through the resonator. That is, the stylus pen touch detection, which is limited in the touch detection by the electrostatic capacity method, can be changed by changing the antenna loop configuration outside the touch sensor panel formed by a plurality of loop structures and the stylus pen inner circuit, And the shape of the electrode pattern without being affected by the shape of the electrode pattern.

1 is a circuit diagram illustrating a touch input system according to an embodiment of the present invention. FIG. 2 is a plan view of the touch sensor panel shown in FIG. 1. Referring to FIG.

1 includes a touch sensor panel including a stylus pen 100, a touch sensor 200 and a loop antenna 400, a touch controller 300, and a stylus grounding unit 500 .

1 and 2, the touch sensor panel 201 is roughly divided into an active area and an outer area. The touch sensor 200 has a plurality of first channels Tx and second channels Rx intersecting with each other and is located in an active area corresponding to the center of the touch sensor panel. An antenna loop 410 is formed outside the active area of the touch sensor panel in a plurality of loops that surround the active area, that is, the both ends are spaced apart from each other to perform an antenna 400 function.

The first channel (Tx) 210 and the second channel (Rx) 220 formed in the active region have a bar shape. The first channel (Tx) 210 and the second channel (Rx) 220 channels cross each other and are disposed in the active area. The first channel (Tx) 210 and the second channel (Rx) 220 are preferably formed as transparent electrodes for light transmission in a display device. The first channel (Tx) 210 is used for applying a driving signal and the second channel (Rx) 220 is used for receiving a detection signal. The first channel (Tx) 210 and the second channel And is electrically connected to the pad 230 provided on the substrate 210 via the routing wiring 225. The shape shown in FIG. 2 may be a bar-shaped channel, and may be changed to another pattern of a capacitance type in some cases. For example, it may be a diamond pattern or some other form of polygonal shape. In any case, in the input system of the present invention, it is required to be formed in a shape having symmetry in all directions from the center to the top, bottom, left and right in order to ensure accuracy of the stylus pen touch.

The antenna loop 410 may be formed in a plurality of loops so as not to overlap with each other in order to receive electromagnetic signals generated from the resonant circuit in the stylus pen 100. [ The antenna loop 410 is a kind of tertiary coil that can induce inductance, but does not have a magnetic core having a separate physical shape. A plurality of pads 230 provided at one side edge of the touch sensor panel 201 are formed on both ends of the antenna loop 410 formed in a plurality of loop shapes and a loop pad 240 formed in parallel with the pad pad 240 is formed, So that it can be detected by the touch controller. Here, the pads 204 electrically connected to both ends of the antenna loop 410 are electrically connected to the touch controller 300.

3 is a circuit diagram showing a portion corresponding to the stylus pen of Fig. 4 is a view schematically showing the stylus pen of Fig. 3. Fig.

Inside the stylus pen 200 shown in Figs. 3 and 4, a primary coil L1 and a secondary coil 120, which are separated from each other, a secondary coil L2 and a resonance circuit 120 connected in series with the secondary coil 120, A capacitor C2 and a switch 130, and a conductive tip 101 connected to the primary coil 140. [

The stylus pen 100 is connected to the stylus ground unit 500 to stabilize the internal circuit of the stylus pen.

The antenna loop 410 and the first channel Tx and the second channel Rx formed in the outer periphery of the touch sensor panel 201 are connected to the touch controller 500 and are subjected to signal control.

The antenna loop 410 in the form of a plurality of loops forms an inductance signal that is resonant from the secondary coil (L2) 120 in the stylus pen 100 when the stylus pen 100 touches the touch sensor panel 201, The mutual inductance M23 between the coil 410 (L3) and the secondary coil L2 or the mutual inductance M13 between the antenna loop 410 (L3) and the primary coil L1.

The touch controller 300 includes an amplifier 310 for amplifying a voltage difference received across the antenna loop 410, a filter unit (AFE) 320 connected to the amplifier 310 to remove noise, a filter unit 320, A signal processor (DSP) 340 for collecting digital signals and extracting coordinates, and a touch sensor panel 201 connected to the converter 330 to convert the analog signal into a digital signal, And a drive signal generator 305 for generating signals to be applied to the respective channels.

Here, when the stylus pen 100 touches the touch sensor panel 201, the internal switch SW 130 of the stylus pen 100 is closed and the secondary coil L2 (L2) 120 and the resonance capacitor C2 are closed, (110) forms a closed circuit as a kind of resonant circuit.

The signal applied to each channel by the drive signal generating unit 305 is a square wave or sinusoidal wave at the same frequency as the in-loop resonance frequency (f = 1 / [2π * (L2 * C2) a sine wave can be applied. The signal applied to each channel is a kind of AC voltage, and each coil has a waveform similar to a signal applied thereto or a signal shape having a waveform that increases with time.

Meanwhile, the stylus ground unit 500 may be a wire tangent to the stylus pen 100 or a wire connected between the stylus pen 100 and the touch sensor panel 201. Ch 510 indicates that when the user touches the stylus pen 100, the user functions as a dielectric and a grounding portion capacitance Ch is generated between the stylus pen 100 and the grounding terminal.

The primary coil (L1) 140 and the secondary coil (L2) 120 inside the stylus pen each have a first mutual inductance () through a magnetic core passing through the inner center axis of the stylus pen 100 M12).

The secondary coil L2 120 and the resonance capacitor C2 110 are connected to the touch sensor 200 through the first and second channels Tx / Rx of the touch sensor panel, And is configured to have an appropriate value to generate electromagnetic resonance with a frequency of a signal input through the coupled sensing capacitor Csx 250. Here, the resonant frequency has a condition of f = 1 / [2? * (L2 * C2) ^ 0.5]). The sensing capacitor Csx 250 is not an element having a physically circuit configuration but is a sensing capacitor Csx that is generated when a conductive tip of the stylus pen 100 touches the sensor panel 201, Lt; / RTI >

The magnetic field signal generated by electromagnetic resonance in the stylus pen 100 is transmitted through the primary coil L1 or 140 or the secondary coil L2 and the antenna loop L3 formed in the touch sensor panel 201 And the second mutual inductance M13 or M23 between the third coil L3 and the third coil L3 410 corresponding to the antenna coil. The induced electromotive force is amplified through an amplifier 310 capable of amplifying a voltage difference between the both ends of the antenna loop 410 and is amplified by a filter unit (AFE) 320 composed of a filter or the like for removing noise After the digital signal is converted into a digital signal by a rough analog-to-digital converter (ADC) 330, the coordinates are extracted from the signal processor (DSP) 340 through an appropriate algorithm, .

On the other hand, one end of the primary coil (L1) 140 in the stylus pen 100 is connected by a stylus tip, and the other end is connected to a conductive body portion made of a conductive material of the stylus to be grounded. In some cases, when the user configures the grounding unit 500, the user is connected to the grounding part capacitor Ch corresponding to the human body.

4, the stylus pen 100 has a shape in which a primary coil L1 and a secondary coil L2 are alternately wound around a magnetic core 135 .

The primary coil L1 140 and the secondary coil L2 120 inside the stylus pen 100 are wound around a magnetic core 135 located in the axial direction of the stylus pen 100 . In this case, the axial direction corresponds to the longitudinal direction of the pen, and corresponds to the Z-axis of the X, Y, and Z coordinate system.

The electroconductive body 150 of the stylus pen 100 includes a primary coil L1 and a secondary coil L2 and a resonant capacitor C2 and a magnetic core 135 And the conductive tip 101 may have a hole through which the conductive tip 101 is partially protruded. Here, the conductive tip 101 is insulated from the conductive body 150 and may further include an insulation buffer (not shown) surrounding the conductive tip 101 around the hole. The conductive body 150 is preferably connected to the stylus ground unit 500 described above.

The switch SW 130 may be formed of a spring or an elastic rubber and may be connected to the conductive tip 101 and the first insulating film 101 so as to maintain insulation from the conductive tip 101. [ (Not shown). Further, the switch 130 operates by the pressure applied when the conductive tip 101 presses the touch sensor panel. That is, when the pressure is higher than a predetermined pressure, the switch 130 is closed, and the internal resonance circuit is closed.

The switch SW 130 may be connected to the secondary coil L2 and the magnetic core 135 may be insulated via the second insulating layer 107. [

One end of the primary coil (L1) 140 is connected to the conductive tip 101 and the other end is connected to the ground terminal 125 of the conductive body 150.

The operation of the stylus pen shown in FIGS. 3 and 4 will be described below.

One end of the primary coil L1 is capacitively coupled with the touch sensor of the touch sensor panel (see 200 in FIG. 6) through the conductive tip 101 to form a detection capacitor Csx 250. Thus, the input signal from each channel of the touch sensor drives the primary coil (L1) 140 through Csx, which is coupled to the secondary coil (L2) 120 through the first mutual inductance (M12) And a resonance capacitor (C2) (110).

The signal input from the drive signal generating section 305 to each channel Tx and Rx of the touch sensor 200 and the electromagnetic wave of the resonance circuit composed of the secondary coil L2 (120) and the resonance capacitor (C2) The circuit configuration is such that the resonance frequencies are the same. In this case, the signal intensity increases with time due to electromagnetic resonance. At this time, the other end of the primary coil (L1) 140 is grounded through a grounded portion capacitor Ch composed of a hand and a human body which are in contact with the conductive body 150 of the stylus pen.

The switch (SW) 130 generates electromagnetic resonance only when the conductive tip 101 is pressed to a certain degree on the surface of the touch sensor panel to enable input sensing of the stylus pen. That is, even if the stylus pen is close to the touch sensor panel, it does not operate unless it is pressed to some extent, thereby preventing malfunction. The magnetic field signal generated in the electromagnetic resonance is transmitted to the antenna loop 410 of a plurality of loops located at the outer periphery of the touch sensor panel to function as a kind of tertiary coil L3 410. The voltage difference (300).

It is possible to generate the detection capacitor Csx 250 and ground through the body portion of the stylus as described above when the stylus pen 100 touches the touch sensor panel 201. [ At this time, a signal applied to the detection capacitor Csx 250 through the conductive tip in the stylus pen 100 is transmitted to the primary coil L1.

Then, the signal transmitted to the primary coil L1 is transmitted to the secondary coil L2 by the first mutual inductance M12. The secondary coil L2 and the resonance capacitor C2 are resonated with the closed circuit formed by closing the switch SW and the signal of the secondary coil L2 becomes larger as time elapses. At this time, the adjacent primary coil L1 can also be affected by the signal of the secondary coil L2 raised by the first mutual inductance M12.

Further, the magnetic field signal of the secondary coil L2 in the resonance circuit is induced to the antenna loop by the second mutual inductance M23.

Detection in this antenna loop proceeds on every channel. It causes electromagnetic resonance through the frequency and the amplitude increases with time.

Since the primary coil L1 or the secondary coil L2 is coupled through the antenna loop in the touch sensor panel and the second mutual inductance M23 when the stylus pen 100 touches the touch sensor panel, The antenna loop can detect the electromagnetic signal generated by the resonance of the stylus pen.

On the other hand, in the antenna loop of the multiple loop structure, the step of detecting the received voltage difference across the antenna loop, the step of amplifying the voltage difference, the step of removing the noise of the amplified voltage difference, Converting the analog signal into a digital signal, and storing the digital signal in a memory, the signal strength digital data for the voltage difference between both ends of the antenna loop corresponding to the channel is stored.

5 is a diagram illustrating a frame driving method of the touch input system of the present invention. 6 is a waveform diagram showing detection waveforms of respective components of the touch sensor panel and the stylus pen.

Referring to FIGS. 5 and 6, the input system of the present invention is time-divisionally driven by dividing one frame for stylus touch detection and for finger touch detection. The stylus touch detection and finger touch detection are alternately performed.

For example, when one frame corresponds to 5 to 10 ms, the frame rate corresponds to 100 to 200 Hz. In this case, when one frame is divided for the stylus touch detection and the finger touch detection, each allocation period corresponds to 2.5 ms to 5 ms. This is when the stylus touch detection and the finger touch detection are divided, and it is also possible to adjust the time of either one of the stylus touch detection and the finger touch detection longer in one frame.

On the other hand, when the number of the first channel Tx and the number of the second channel Rx are m and n, respectively, when the stylus touch is detected, m channels Tx (1) to Tx (m) Sequentially drives and detects n channels Rx (1) to Rx (n) of two channels. That is, the total 'm + n' channels are sequentially driven within the stylus touch detection section. Therefore, assuming that 'm + n' = 50, for example, the possible time for driving one channel is 50 μs to 100 μs divided by 50 from 2.5 ms to 5 ms.

When the finger touch is detected, a driving signal is sequentially applied to the first channel (Tx), a detection signal is detected in the second channel (Rx), and a change according to the touch is detected to detect the touch position . Since the driving signal is applied only to the first channel (Tx) at the time of detecting the finger relatively, the angle of the finger touch detection is smaller than the signal application time (2.5 ms to 5 ms / (m + The driving signal application time (2.5 ms to 5 ms / m) of the first channel (Tx) may be long.

In this case, the signal waveform and the detection waveform for driving each channel are alternately driven by time division of the stylus input and finger touch, as described later.

6 shows a process of driving a channel of Tx (n), this process is performed in the same manner as Tx (0) to Tx (n) in the same manner. 5), Rx (0) to Rx (5), and touch detection is performed by a voltage difference received at both ends of the antenna loop 410 for each channel.

Touch detection is performed by electrically connecting the detection capacitor Csx between the conductive tip and the touch sensor panel 201 to the primary coil L1 and by closing the switch SW to connect the secondary coil L2 and the resonant capacitor C2 is formed and the induced electromotive force that is electromagnetically resonated by the antenna loop 410 is received by the secondary coil L2 or the primary coil L1 and the second mutual inductance M23 between the antenna loops .

A signal to be applied to the plurality of channels Tx (0) to Tx (5), Rx (0) to Rx (5) may be a square wave or sinusoidal wave having the same frequency as the resonance frequency in the resonance circuit.

The stylus pen 100 can be grounded by the user when the stylus pen 100 is touched on the surface of the touch sensor panel 201. [ Here, the user contacts the conductive body directly or connects the conductive body to the touch sensor panel through the wire when the grounding is performed.

When driving the Tx (5) channel of FIG. 6, T1 is applied to the Tx (5) channel with a square wave or sinusoidal wave of a constant frequency from the touch controller. Then, it is possible to detect only signals received in the circuit and the antenna loop, without applying a signal to the Tx (5) channel during the time T2. That is, when a rectangular wave or a sinusoidal signal is applied to the Tx (5) channel, the primary coil L1 of the stylus pen during this time is connected to the sensing capacitor Csx generated by the capacitive coupling between the Tx channel and the conductive tip When the stylus pen is touched on the surface of the touch sensor panel, electrical connection is established between the sensing capacitor (Csx) and the conductive tip, thereby generating a weak waveform in synchronization with the square wave in the primary coil. Which is again coupled between the primary coil and the secondary coil to form a first mutual inductance M12 through which the secondary coil is driven. Here, the waveform of the secondary coil becomes larger as time elapses within T1 time, because it causes electromagnetic resonance through the resonance frequency and resonance frequency of the series-connected resonance capacitor C2 in the resonance circuit of the closed circuit, and the amplitude increases with time .

Since the primary coil L1 or the secondary coil L2 is coupled through the antenna loop in the touch sensor panel and the second mutual inductance M23 when the stylus pen 100 touches the touch sensor panel, The loop can detect the electromagnetic signal generated by the resonance of the stylus pen.

If all of the signal strength digital data for each channel of one frame is collected through this process, coordinates of the place where the stylus pen is located are extracted through the signal processing unit of the touch controller.

On the other hand, as shown in the drawing, the signal application period of the stylus pen may be provided only by applying T1 alone, or the signal detection period may be separately provided or the signal application and detection may be performed simultaneously in the time period T1 + T2. In the case where the signal reception interval is T1 + T2, the time for receiving the signal is prolonged, so that the accuracy of the measured signal can be expected to increase. However, during the T1 time, the Tx or Rx channels are driven and parasitic loops of these channels can induce magnetic field signals, which become noise components in the antenna loop, and this noise, together with the signals generated by the resonant circuit inside the stylus pen Can be received on the antenna loop side.

Therefore, when the magnetic field interference caused by the parasitic loop is difficult to accurately detect, touch detection can be performed by detecting the resonance signal of the stylus pen only in the T2 period. In this case, since the resonance signal is not received for the T1 time, the signal reception time reduction and the data precision can be reduced, but there is an advantage that the magnetic field noise does not affect the antenna loop.

FIG. 7 is another plan configuration diagram illustrating the antenna loop of the multiple loop structure shown in FIG. 2. FIG.

An antenna loop 410 is formed outside the active area of the touch sensor panel 201 shown in FIG. 7 in the form of a plurality of loops spaced apart from each other, Function.

An antenna loop 410 of a plurality of loops is formed to surround an active area in an outer area of the touch sensor panel 201 in order to receive an electromagnetic signal generated from the resonance circuit in the stylus pen 100. In particular, the antenna loops 410 may be formed not to overlap with each other in the form of three or more loops as shown in Fig. 7, instead of the two-turn loops shown in Fig. Since the reception sensitivity of the electromagnetic signal is proportional to the number of loop times, the reception sensitivity of the electromagnetic signal also improves as the number of refresh times increases. Therefore, the antenna loop 410 of the multiple loop structure can improve the reception sensitivity of the electromagnetic signal without changing the cross-sectional area thereof. The antenna loop 410 of the multiple loop structure is a kind of tertiary coil that can induce inductance, but does not have a magnetic core having a separate physical shape. Here, the plurality of antenna loops 410 may be coils operating via an air core between the stylus pens.

The antenna loop 410 of the multiple loop structure is formed as large as possible than the active touch region where stylus input is actually performed and coordinate extraction is performed. This is to solve the edge effect in which the accuracy of coordinate extraction is deteriorated due to the asymmetry of the channel at the edge of the touch sensor panel 201 in the touch detection using the stylus pen 100. [

A plurality of pads 230 provided at one side edge of the touch sensor panel 201 are formed at each end of one side and the other side of the antenna loop 410 having a plurality of loop structures and a loop pad 240 formed side by side is formed, So that the voltage difference can be detected by the touch controller. Here, the pad 204 electrically connected to one end and the other end of the antenna loop 410 are electrically connected to the touch controller 300. The antenna loop 410 receives the inductance signal resonant from the secondary coil L1 in the stylus pen 100 when the touch sensor panel 201 of the stylus pen 100 touches the antenna loop 410 The mutual inductance M23 between the coil L2 and the antenna coil 410 or L3 and the mutual inductance M13 between the primary coil L1 are induced.

8A to 8C are waveform diagrams illustrating input / output waveforms input / output to / from a loop pad according to the number of loops of the antenna loop according to the present invention.

8A, a voltage of 5V in a frequency waveform of 500kHz may be supplied to a loop pad of one side of the antenna loop 410 in a 500kHz frequency waveform through the drive signal generating unit 305. [

When the antenna loop 410 is configured with a one-time loop structure (N = 1), the detection signal detected at the other loop pad of the antenna loop 410 is detected as a waveform of about 7.89 mV in magnitude.

However, when the antenna loop 410 is configured with a two-time loop structure (N = 2), the detection signal detected at the other side loop pad of the antenna loop 410 is detected as a waveform of about 15.78 mV, (N = 1) can be detected.

The touch input system of the present invention and the touch detection method using the touch input system according to the present invention can detect the touch of the stylus pen 100 and the finger touch by different driving methods, the palm rejection is facilitated. In particular, the touch sensitivity and accuracy of the touch sensor panel 201 are improved by the antenna loop 410 of the touch sensor panel 201 having a plurality of loop structures.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. Will be apparent to those of ordinary skill in the art.

100: Stylus Pen 101: Conductive tip
103, 107: Insulating film 110: Resonant capacitor
120: secondary coil 130: switch
140: primary coil 200: touch sensor
201: touch sensor panel 250: sensing capacitor
300: touch controller 305: driving signal generator
310: amplifier 320: filter unit
330: converter 340: signal processor
400: antenna 410: antenna loop

Claims (10)

A touch sensor panel having a first channel and a second channel intersecting with each other;
A stylus pen including a primary coil and a secondary coil separated from each other, a resonant capacitor and a switch connected in series with the secondary coil, and a conductive tip connected to the primary coil;
A grounding portion connected to the stylus pen;
An antenna loop formed in a plurality of loop structures formed outside the sensor panel; And
And a touch controller connected to the first channel and the second channel and the antenna loop. The method according to claim 1,
The antenna loop of the multiple loop structure
And receives an inductance signal resonated from the primary coil in the stylus pen when the touch sensor panel surface of the stylus pen is touched. 3. The method of claim 2,
The antenna loop of the multiple loop structure
Wherein the touch sensor panel is formed so as to surround a front surface of the touch sensor panel, and pads are provided at both ends of one side and the other side, respectively, and connected to the touch controller. The method according to claim 1,
The antenna loop of the multiple loop structure
The inductance of the antenna loop itself and the secondary coil inter-inductance, or the antenna loop itself and the primary coil-to-ground inductance induction circuit, when the touch sensor panel touches the stylus pen, The touch input system comprising: The method according to claim 1,
The touch controller
An amplifier coupled to the antenna loop for amplifying the voltage difference received across the antenna loop;
A filter unit connected to the amplifier to remove noise;
A converter connected to the filter unit to convert an analog signal into a digital signal;
A signal processing unit connected to the converter to collect digital signals and extract coordinates; And
And a drive signal generator for generating a signal to be applied to each channel in the sensor panel. A sensor panel having a plurality of first and second channels intersecting with each other, a primary coil and a secondary coil which are separated from each other, a resonant capacitor and a switch connected in series with the secondary coil, A touch detection method of an input system having a stylus pen including a connected conductive tip and an antenna loop formed in a plurality of loop structures outside the sensor panel,
Wherein the detection of the finger touch of each frame and the detection of the stylus pen touch are time-divided. The method according to claim 6,
In the stylus pen touch detection,
Sequentially applying signals to the plurality of first and second channels,
Wherein the touch detection is performed by a voltage difference received at both ends of the antenna loop of the plurality of loop structures. 8. The method of claim 7,
The antenna loop of the multiple loop structure
Wherein the touch sensor panel is formed so as to surround a front surface of the touch sensor panel, and pads are provided at both ends of one side and the other side, respectively, and connected to the touch controller. 9. The method of claim 8,
The touch detection
And a primary coil-to-primary electrical connection is formed between a detection capacitor between the conductive tip and the sensor panel,
The switch is closed to form a resonance circuit of the secondary coil and the resonance capacitor,
And an electromagnetic electromagnetically resonant induced electromotive force is received by the antenna loop of the multiple loop structure by the mutual inductance between the primary coil and the secondary coil. The method according to claim 6,
The touch detection by the touch controller
Detecting a voltage difference received at both ends of the antenna loop of the multiple loop structure sequentially for the plurality of first and second channels;
Amplifying the voltage difference;
Removing noise of the amplified voltage difference;
Converting the noise-removed amplified voltage difference from an analog signal to a digital signal; And
Storing the digital signal in a memory,
And detecting touch coordinates by calculating a digital signal stored in a memory for each of the plurality of first and second channels.

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