KR101821288B1

KR101821288B1 - Mobile terminal comprising a stylus pen and a touch panel and method for controlling the mobile terminal

Info

Publication number: KR101821288B1
Application number: KR1020150164951A
Authority: KR
Inventors: 심현재; 이정준; 안병교; 김영환; 김원수
Original assignee: 엘지전자 주식회사
Priority date: 2015-11-24
Filing date: 2015-11-24
Publication date: 2018-01-23
Also published as: KR20170060469A

Abstract

The present invention relates to a mobile terminal including a stylus pen and a touch panel, and more particularly, to a mobile terminal capable of transmitting and receiving an electric signal between a touch panel and a stylus pen. A mobile terminal according to an embodiment of the present invention includes a touch panel having a plurality of touch panel electrodes, a stylus pen configured to transmit and receive an electric signal to and from the touch panel using the capacitive coupling, A plurality of voltages having different frequencies are applied to the touch panel such that electrical signals are transmitted through the capacitive coupling, and when an electrical signal is received from the stylus pen, a frequency of the received electrical signal is substituted for the plurality of voltages And a control unit for applying a voltage to the touch panel.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a mobile terminal including a stylus pen and a touch panel,

The present invention relates to a mobile terminal including a stylus pen and a touch panel, and more particularly, to a mobile terminal capable of transmitting and receiving an electric signal between a touch panel and a stylus pen.

2. Description of the Related Art Touch panels are used as means for inputting characters, pictures, and the like in various electronic devices such as mobile phones and personal computers. The touch panel senses the touch of the hand or the stylus pen and performs signal processing for converting it into an electric signal.

When an electronic circuit is built in the stylus pen, it can perform a mouse function such as selecting a part of an image or dragging an electric signal from a stylus pen as well as a simple touch input.

In this manner, when an electronic circuit is built in the stylus pen, electric power is required to operate the electronic circuit of the stylus pen. For example, there is a method of supplying power from a built-in battery by incorporating a battery into the stylus pen.

In recent years, a method has been used in which a separate dedicated panel for power supply is provided in a main body of a cellular phone, and a necessary power is supplied wirelessly from a separate dedicated panel to the stylus pen.

(Patent Document 1) JP 4866941 B

The power supply technique disclosed in Patent Document 1 is performed by a separate power transmission device 4 disposed under the LCD module 3 in a smartphone. Here, the power transmission device 4 discloses a method of transmitting electric power to a coil inside the stylus pen by means of an induction coil. That is, in Patent Document 1, a separate power transmission apparatus including an induction coil for supplying power to the stylus pen is disposed under the LCD module, and a coil provided in the stylus pen and an inductive coupling Lt; / RTI >

However, as described above, separately installing a power transmission device including an induction coil below the LCD module to supply power to the stylus pen causes an increase in cost, which increases the thickness of the mobile phone.

In addition, when the electrode line of the touch panel is made into a coil, since the resistance component due to the electrode lines of the touch panel is large, the energy is released as heat by the resistance before the circuit is in the resonance state, There is a problem.

In order to solve such a problem, there is an increasing need for a technology for supplying power to the stylus pen using an existing touch panel and sensing a signal received from the stylus pen without a separate power transmission device.

It is an object of the present invention to provide a mobile terminal including a stylus pen and a touch panel capable of transmitting and receiving an electric signal between a touch panel and a stylus pen by a capacitive coupling method, and a control method thereof.

It is another object of the present invention to provide a mobile terminal including a stylus pen and a touch panel capable of transmitting and receiving an electric signal between a touch panel and a stylus pen with optimized efficiency and a control method thereof.

A mobile terminal including a stylus pen according to an embodiment of the present invention includes a touch panel having a plurality of touch panel electrodes, a stylus pen configured to transmit and receive an electric signal to and from the touch panel, A plurality of voltages having different frequencies are applied to the touch panel so that an electrical signal is transmitted through the capacitive coupling with the stylus pen, and when an electrical signal is received from the stylus pen, And a controller for applying a voltage having a frequency of an electric signal to the touch panel.

In an embodiment, the control unit sequentially applies the plurality of voltages to the touch panel.

In an embodiment, the control unit may simultaneously apply at least two voltages among the plurality of voltages to the touch panel.

In one embodiment, the touch panel includes a plurality of TX electrodes and a plurality of RX electrodes arranged to cross the TX electrodes, wherein the controller is configured to apply a plurality of voltages having different frequencies to the plurality of TX electrodes Respectively.

In one embodiment of the present invention, the control unit applies a voltage having a first frequency among the plurality of voltages to a first TX electrode of the plurality of TX electrodes, and a second frequency different from the first frequency And applying a voltage to the second TX electrode different from the first TX electrode among the plurality of TX electrodes.

In another embodiment of the present invention, when the electric signal is not received through the plurality of RX electrodes for a preset time after the application of the plurality of voltages, the control unit controls the frequency of the voltage applied to the plurality of TX electrodes And the plurality of voltages are applied to the TX electrode so that a voltage having a frequency is applied.

In one embodiment, the frequency of the electric signal transmitted from the stylus pen may be changed based on the pressure of the stylus pen, and the controller may change the frequency of the received electric signal to a voltage having the changed frequency, To the touch panel.

A method of controlling a mobile terminal having a stylus pen according to an embodiment of the present invention includes the steps of applying a plurality of voltages having different frequencies to a touch panel, Receiving an electrical signal from the stylus pen, determining the frequency of the received electrical signal, and applying a voltage having the determined frequency to the touch panel.

According to the present invention, a plurality of voltages having different frequencies are applied to a touch panel to charge the stylus pen with electrical energy, and when an electrical signal is received from the stylus pen, a voltage having a frequency of the received electrical signal Can be applied to the touch panel. Accordingly, by applying a voltage having a resonance frequency of the stylus pen to the touch panel, the electrical signal transmission / reception ratio between the touch panel and the stylus pen can be remarkably improved.

Further, according to the present invention, a plurality of voltages having a plurality of frequencies are applied to a touch panel, and only a voltage having a resonance frequency of the stylus pen is applied to the touch panel, thereby power consumption can be remarkably reduced.

Further scope of applicability of the present invention will become apparent from the following detailed description. It should be understood, however, that the detailed description and specific examples, such as the preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art.

1 is a conceptual diagram illustrating a mobile terminal having a stylus pen and a touch panel.
2A and 2B are conceptual diagrams illustrating a stylus pen according to an embodiment of the present invention.
3 is a conceptual diagram illustrating a touch panel electrode included in a touch panel according to an embodiment of the present invention.
FIG. 4 is a circuit diagram illustrating a method of transmitting and receiving an electric signal through a capacitive coupling, according to an exemplary embodiment of the present invention. Referring to FIG.
5 is a conceptual diagram for explaining a resonance frequency of a stylus pen according to an embodiment of the present invention.
6 is a flowchart for explaining an exemplary control method of the present invention.
7 is a conceptual diagram for explaining the control method shown in FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, wherein like reference numerals are used to designate identical or similar elements, and redundant description thereof will be omitted. The suffix "module" and " part "for the components used in the following description are given or mixed in consideration of ease of specification, and do not have their own meaning or role. In the following description of the embodiments of the present invention, a detailed description of related arts will be omitted when it is determined that the gist of the embodiments disclosed herein may be blurred. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. , &Lt; / RTI > equivalents, and alternatives.

Terms including ordinals, such as first, second, etc., may be used to describe various elements, but the elements are not limited to these terms. The terms are used only for the purpose of distinguishing one component from another.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between.

The singular expressions include plural expressions unless the context clearly dictates otherwise.

In the present application, the terms "comprises", "having", and the like are used to specify that a feature, a number, a step, an operation, an element, a component, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

The mobile terminal described in this specification includes a mobile phone, a smart phone, a laptop computer, a digital broadcasting terminal, a personal digital assistant (PDA), a portable multimedia player (PMP), a navigation device, a slate PC A tablet PC, an ultrabook, a wearable device such as a smartwatch, a smart glass, and a head mounted display (HMD). have.

However, it will be appreciated by those skilled in the art that the configuration according to the embodiments described herein may be applied to fixed terminals such as a digital TV, a desktop computer, a digital signage, and the like, will be.

Referring to FIG. 1, FIG. 1 is a conceptual diagram illustrating a mobile terminal having a stylus pen and a touch panel.

The mobile terminal 10 according to an embodiment of the present invention may include a display unit 151 (or a touch screen 151), a controller (not shown) and a stylus pen 20 for controlling the same.

The display unit 151 may include a touch panel 200 (or a touch sensor) that senses a touch to the display unit 151 so that a control command can be received by a touch method.

The touch panel 200 is formed in a film form having a touch pattern and disposed between a window (not shown) of the display unit 151 and a display (not shown) on the back of the window, or is directly patterned on the back surface of the window It may be a metal wire. Alternatively, the touch panel 200 may be formed integrally with the display. For example, the touch panel 200 may be disposed on the substrate of the display, or may be provided inside the display.

That is, the display unit 151 may have a mutual layer structure with the touch panel 200 or may be integrally formed to realize a touch screen.

The display unit 151 may function as a user input unit for providing an input interface between the mobile terminal 10 and a user and may provide an output interface between the mobile terminal 10 and the user.

The display unit 151 may display (output) information processed by the mobile terminal 10. [ For example, the display unit 151 may display execution screen information of an application program driven by the mobile terminal 10, or UI (User Interface) and GUI (Graphic User Interface) information according to the execution screen information .

The display unit 151 can sense a touch (or a touch input) applied to the touch screen (or the display unit 151) by using the touch panel 200 in an electrostatic capacity manner.

As an example, the touch panel 200 may be configured to convert a change in a pressure applied to a specific portion of the touch screen or a capacitance generated in a specific portion to an electrical input signal. The touch panel 200 may be configured to detect a position, an area, a pressure at the time of touch, a capacitance at the time of touch, and the like where a touch object to be touched on the display unit 151 is touched on the touch sensor . Here, the touch object may be a finger, a touch pen, a stylus pen 20, a pointer, or the like as an object to which a touch is applied to the touch sensor.

When there is a touch input to the touch panel 200, the signal (s) corresponding thereto is sent to the signal receiving unit (or the touch controller). The signal receiving unit processes the signal (s) and transmits corresponding data to the control unit. Thus, the control unit 180 can know which area of the display unit 151 is touched or the like. Here, the signal receiving unit may be a separate component from the control unit, and may be the control unit itself.

Meanwhile, the control unit may perform different controls or perform the same control according to the type of the touch object touching the touch screen (or a touch key provided in the touch screen). Depending on the kind of the touch target object, whether to perform different controls or to perform the same control may be determined according to the current operating state of the mobile terminal 100 or an application program being executed.

There may be two or more display units 151 according to the embodiment of the mobile terminal 10. In this case, the mobile terminal 10 may be provided with a plurality of display portions which are spaced apart from one another or may be disposed integrally with each other, or may be disposed on different surfaces, respectively.

The mobile terminal 10 can sense the touch (or input) applied by at least one of the stylus pen 20 as the first input means and the finger as the second input means using the touch panel 200. [ Specifically, when a touch is applied by at least one of the first and second input means, the touch panel 200 transmits a signal generated by the touch to the control unit.

Further, the control unit 180 can determine the type of the input means to which the touch is applied based on the transmitted signal. Further, the control unit 180 can detect a point (position, part) where the touch is applied based on the transmitted signal.

Hereinafter, a stylus pen will be described as an example of a means for inputting a user command on the touch panel. The present invention relates to a method for supplying an electric signal with such a stylus pen and sensing an electric signal transmitted from the stylus pen.

Specifically, in the present invention, a voltage is applied to an electrode of a touch panel 200, and a voltage is applied to the touch panel 200 through a coupling capacitance (capacitive coupling) formed between the stylus pen 20 and the electrode of the touch panel 200, To a method of supplying an electric signal from the electrode of the stylus pen (200) to the stylus pen (20).

The present invention is also applicable to an electric signal (for example, an LC resonance signal) generated in the stylus pen 20 through a coupling capacitance (capacitive coupling) formed between the stylus pen 20 and the touch panel 200, To the touch panel (200).

In order to transmit an electric signal between the stylus pen 20 and the signal receiving unit (or the control unit) in a capacitive manner, the TX electrode (driving electrode or driving electrode) of the touch panel, Or an RX electrode (sensing electrode) is used.

In addition, the stylus pen 20 of the present invention does not have a separate power supply for supplying an electric signal to the touch panel 200, and receives an electric signal from the touch panel 200 using an LC circuit, And transmits the electric signal to the touch panel 200 using the touch panel 200. [

In addition, when an electric signal is received from the stylus pen 20 through the electrostatic capacitive coupling to the touch panel 200, the position of the stylus pen (or the position of the stylus pen 20) (Position, coordinates, and the like)) of the object.

Hereinafter, a stylus pen according to an embodiment of the present invention will be described in more detail with reference to the accompanying drawings. 2A and 2B are conceptual diagrams illustrating a stylus pen according to an embodiment of the present invention.

2A, a stylus pen 20 according to an embodiment of the present invention may be configured such that a coil L element Ls, a capacitor C element C and a capacitor C element C are used without using a power dissipation element such as a transistor or a diode, CS) or an LC circuit 22 (or an LC resonance circuit). Here, the LC circuit 200 may include a variable capacitance capacitor C whose capacitance changes according to a force applied to the stylus pen 20. [

Since the LC circuit 22 basically does not consume power, a separate power source for driving the circuit in the stylus pen 20 may not be provided.

In order to start the resonance operation of the LC circuit 22 of the stylus pen 20, it is necessary to give a start signal of the resonance operation. To give such a start signal is to give an initial condition of resonance, specifically, to receive an electric signal (or electric energy) from the outside (touch panel 200).

A mutual capacitance CM may be formed between the stylus pen 20 and the touch panel 200 through a capacitive coupling. That is, the stylus pen 20 and the touch panel 200 of the present invention do not use the inductive coupling, and the mutual capacitance formed between the touch panel 200 and the stylus pen 20 by the capacitive coupling It is possible to transmit and receive electric signals through CM (capacitance CM by capacitance coupling).

The size of the mutual capacitance CM formed between the stylus pen 20 and the touch panel 200 increases as the distance between the stylus pen 20 and the touch panel 200 increases. The larger the usable area between the electrodes 200 becomes.

To this end, an AC voltage is applied to the touch panel 200. The stylus pen 20 receives an electric signal (power energy) corresponding to the AC voltage from the touch panel 200 to which the AC voltage is applied through the electrostatic capacitive coupling. Resonance is generated in the LC circuit 22 provided in the stylus pen 20 by an electric signal transmitted from the touch panel 200. [

More specifically, when the frequency of the AC voltage and the LC resonance frequency are different from each other, the LC circuit 22 of the stylus pen 20 mixes the vibration having the LC resonance frequency component and the vibration having the frequency component of the AC power source Vibration is achieved.

Since the LC resonance itself does not involve consumption of electric power, even if the AC power supply is interrupted, the LC circuit 22 maintains LC resonance continuously. In practice, however, resistance components exist in the wiring and the inductor L constituting the LC circuit 22, and the vibration energy is released (consumed) as thermal energy. Therefore, the amplitude of the LC resonance gradually decays as time passes. At this time, even if the AC voltage is continuously supplied, the attenuation of the LC resonance continues, and as a result, the oscillation of the LC resonant frequency component becomes zero. However, the vibration having the frequency component of the AC power source continues to exist without attenuation while the AC power is continuously supplied.

When the supply of the AC voltage applied to the touch panel 200 is stopped, the LC resonance circuit which has oscillated at the frequency of the AC voltage so far immediately stops oscillation at the AC power supply frequency and starts oscillation at the LC resonance frequency.

On the other hand, the LC resonance frequency can be defined by the coil capacitance of the L element provided in the LC circuit 22 and the capacitance of the C element. Here, the LC circuit 22 includes a fixed capacitance Cs and a variable capacitance C.

The variable capacitance C can be changed, for example, by applying an external force to the stylus pen 20. An external force is applied to the stylus pen 20 when the stylus pen 20 touches (or pressurizes) the touch panel 200 by the user or when the stylus pen 20 has a variable capacity A case where a pressure is applied to a button that can change the capacitance? C, and the like.

When the variable capacitance C included in the LC circuit 22 is changed by an external force, the LC resonance frequency of the LC circuit 22 can be changed. Accordingly, the LC resonance frequency of the electric signal output from the stylus pen 20 is changed, and the control unit controls the stylus pen 20 to be touched with the touch panel 200 using the changed LC resonance frequency sensed by the touch panel 200 20 can be detected.

For example, the capacity? C of the variable capacitor takes different values based on the touch pressure (or pressure) applied to the touch panel 200 by the stylus pen 20. [ As a result, the LC resonance frequency also becomes a different value. That is, the first electrical signal added to the touch panel from the stylus pen 20 before the touch is applied is converted into a second electrical signal having a frequency different from the LC resonance frequency included in the first electrical signal, And detects the pressure based on the second electrical signal.

The principle of detecting the pressure in the present invention can be understood as detecting the frequency of the resonance signal (accurately, the frequency of the resonance signal) generated by the LC resonance circuit incorporated in the stylus pen.

When the application of the AC voltage to the touch panel 200 is stopped, the touch panel 200 receives an electric signal having the LC resonance frequency from the stylus pen 20. [ More specifically, when supply of the electric signal corresponding to the AC voltage is stopped from the touch panel 200, the stylus pen 20 transmits the electric signal resonated by the LC circuit 22 to the touch panel 200 through the electrostatic capacitive coupling To the touch panel (200).

The control unit detects the position of the stylus pen 20 (or the point at which the stylus pen 20 is touched to the touch panel 200) based on the electric signal received by the touch panel 200, .

A specific method of detecting the position of the stylus pen 20 will be described later with reference to the accompanying drawings.

Hereinafter, the stylus pen 20 according to an embodiment of the present invention will be described in more detail with reference to FIG. 2B.

The stylus pen 20 according to an embodiment of the present invention may be formed to transmit and receive an electric signal with the touch panel 200 using an electrostatic capacitive coupling. The stylus pen 20 for generating electrostatic capacitive coupling with the touch panel is formed of a main body 21 and a conductor and protrudes to the outside of the main body 21 to touch the touch panel 200 (Not shown). The stylus pen 20 may also include an LC circuit 22 provided in the main body 21 and including an inductor Ls and capacitors Cs and C.

The LC circuit 22 may be electrically connected to the pen tip 23 to generate a capacitive coupling with the touch panel 200. A more detailed description of the electrical connection between the LC circuit 22 and the pen tip 23 will be described later. First, a detailed description of each configuration will be described in more detail.

The main body 21 serves as a case that forms the appearance of the stylus pen 20. [ A space may be formed in the main body 21 and components constituting the stylus pen 20 such as the LC circuit 22 and the conductive member 24 may be disposed in the space.

The main body 21 may be formed of various materials. For example, the main body 21 may be formed by injection molding synthetic resin, or may be formed of metal such as stainless steel (STS), aluminum (Al), titanium (Ti), or the like.

Since the main body 21 forms an outer appearance of the stylus pen 20, any substance may be used as long as it is a material having a reference strength that can maintain the appearance at a certain level. The stylus pen 20 may be formed of a conductive material or a nonconductive material. The stylus pen 20 may be formed of a conductive material or a nonconductive material. It is preferable to be formed of a nonconductive material. When an electric signal flows through an object using the stylus pen 20, an electric signal transmitted and received through the capacitive coupling between the touch panel 200 and the stylus pen 20 is changed to determine a touch point The electric signal used becomes unstable.

Meanwhile, the stylus pen 20 of the present invention may include a pen tip 23 protruding outside the main body 100 and formed to touch the touch panel. The pen tip 23 may be formed of a conductor. Specifically, the pen tip 23 may be formed by a conductor formed entirely of the material forming the pen tip 23, or only a portion forming the surface of the pen tip 23.

In addition, the pen tip 23 may be electrically connected to the LC circuit 22. Here, the electrical connection means that the pen tip 23 formed of a conductor and the LC circuit 22 are connected by an object (for example, electric wire, wiring) capable of directly transmitting and receiving electric signals have.

In the present invention, the pen tip 23 is formed as a conductor, and the pen tip 23 and the LC circuit 22 are electrically connected to each other by electrostatic coupling between the touch panel 200 and the stylus pen 20. [ It is possible to increase the size of the electric signal transmitted /

Specifically, the capacitive coupling can be generated between the touch panel electrode of the touch panel 200 and the capacitor (C element) constituting the LC circuit 22 of the stylus pen 20. That is, the capacitive coupling can be generated as the stray capacitance CP existing in the touch panel electrode and the capacitors Cs and C included in the LC circuit 22 are adjacent to each other. In addition, as the capacitive coupling is generated, a mutual capacitance CM can be generated (formed) between the touch panel 200 and the stylus pen 20. FIG.

Electrical signals transmitted between the touch panel 200 and the stylus pen 20 may be related to the mutual capacitance CM. That is, as the mutual capacitance CM increases, the magnitude of the electric signal transmitted / received increases.

Here, the increase in the size of the electrical signal means that the size of the electrical signal itself increases, the transmission / reception ratio of the electrical signal increases, and the amount of the electrical signal increases.

The capacitor of the LC circuit 22 has an effect of being positioned on the pen tip 22 as the pen tip 23 and the LC circuit 22 are electrically connected to each other. Furthermore, the distance between the touch panel electrode of the touch panel 200 and the capacitor of the stylus pen 20 has the effect of making the LC circuit 22 closer to the pen tip 23, which is formed by the conductor, before it is electrically connected.

Here, the mutual capacitance (CM) increases as the distance between two objects (touch panel electrode and pen tip) forming mutual capacitance due to the characteristics of the capacitor becomes closer. Accordingly, the magnitude of the electric signal transmitted / received between the touch panel 200 and the stylus pen 20 increases as the LC circuit 22 is electrically connected to the pen tip 22 formed of a conductor.

The stylus pen 20 receives an electric signal transmitted from the touch panel 200 through a pen tip 23 formed of a conductor and transmits the received electric signal to an LC circuit 22 electrically connected to the pen tip 23 ). That is, in the LC circuit 22, resonance may be generated by an electrical signal supplied from the pen tip 23. [

Accordingly, the LC circuit 22 can enter the resonance state faster than when the electric signal is directly supplied to the touch panel electrode by receiving the electric signal through the pen tip 23.

Further, the stylus pen 20 can transmit an electric signal generated by the LC circuit 22 to the touch panel 200. The electric signal generated in the LC circuit 22 can be transmitted to the touch panel 200 according to the electrostatic capacitive coupling method through the pen tip 23 formed of a conductor electrically connected to the LC circuit 22 have.

The electric signal generated in the LC circuit 22 is transmitted to the touch panel 200 through the pen tip 23 formed by a conductor so that the signal level of the electric signal received by the touch panel 200 Can be increased.

On the other hand, the pen tip 23 may have various shapes. For example, when the pen tip 23 is formed in the shape of a horn having one bottom surface and one vertex, and the vertex of the horn-shaped pentette 23 is directed to the outside of the main body 21, The size of the electric signal transmitted and received between the pen tip 23 and the touch panel 200 may increase as the pen tip 23 tilts.

Specifically, when the pen tip 23, which is in the shape of a horn, is inclined, the mutual capacitance generated by the capacitive coupling is proportional to the area and increases due to the characteristics of the capacitor in inverse proportion to the distance. The size of the electric signal transmitted / received between the panel 200 increases in proportion to the degree of inclination of the pen tip 23.

The pen tip 23 is formed in the shape of a hemisphere and when the bottom surface of the pen tip 23 formed in the hemisphere is disposed to be in contact with the main body, The size of the electric signal can be kept constant even if the stylus pen 20 is tilted. In this case, even if the stylus pen is tilted in the present invention, the stability of the electric signal transmitted and received between the touch panel 200 and the stylus pen 20 can be improved.

The stylus pen of the present invention may further include a conductive member (24) provided in the body and electrically connected to the LC circuit to increase the size of the electrical signal. The conductive member 24 may be provided inside the main body 21 and may be electrically connected to the LC circuit 22, as shown in FIG. 2B. Here, the electrical connection means that the conductive member 24 and the LC circuit 22 are electrically connected to each other by an object (for example, a liquid crystal display panel) in which the LC circuit 22 is electrically connected to the pen tip 23 For example, a wire).

2, in the present invention, by electrically connecting the LC circuit 22 and the conductive member 24, it is possible to increase the size of an electrical signal transmitted / received between the touch panel 200 and the stylus pen 20 . The conductive member 24 may be understood to serve as a virtual ground (GND).

Hereinafter, a touch panel for transmitting and receiving an electric signal to and from the stylus pen described with reference to FIGS. 2A and 2B will be described in detail with reference to the accompanying drawings.

FIG. 3 is a conceptual diagram illustrating a touch panel electrode included in a touch panel according to an exemplary embodiment of the present invention. FIG. 4 is a cross-sectional view of a stylus pen and a touch panel according to an exemplary embodiment of the present invention. And is a circuit diagram for explaining a method of transmitting and receiving.

The touch panel 200 according to an embodiment of the present invention may include a plurality of touch panel electrodes 50, a voltage supply unit 110, switches 120a and 120b, and a signal receiving unit 130. [

The signal receiving unit 130 (or the touch controller) receives the signal (s) received from the touch panel electrode 50 when an electrical signal is supplied from the stylus pen 20 to the touch panel electrode 50, And then transmitting the corresponding data to the control unit. Here, the signal receiving unit 130 may be a separate component from the control unit 180, and may be the control unit 180 itself.

Referring to FIG. 3, the touch panel electrode 50 of the touch panel 200 may include a plurality of TX electrodes (lines) 51 and a plurality of RX electrodes (lines) 52. Here, the TX electrode 51 may be referred to as a driving electrode (line), the driving electrode (line), and the RX electrode 52 may be named as a sensing electrode (line).

The plurality of TX electrodes 51 and the plurality of RX electrodes 52 may be arranged in a grid or matrix form. More specifically, the plurality of TX electrodes 51 are arranged so as to have a constant interval in a first direction (for example, the Y-axis direction), and the plurality of RX electrodes 52 intersect with the plurality of TX electrodes 51 And may be arranged to have a constant interval in a second direction different from the first direction (for example, the X-axis direction). Here, the first direction and the second direction may be perpendicular to each other.

4, the touch panel 200 of the present invention includes a voltage supply unit 110 for applying a voltage to a touch panel electrode 50, a signal for processing an electric signal received (detected) by the touch panel electrode 50, Switch parts 120a and 120b for selectively connecting the TX electrode 51 and the RX electrode 52 included in the touch panel electrode 50 to the voltage supply part 110 and the signal reception part 130, . &Lt; / RTI >

At least one of the voltage supplying unit 110, the switch unit 120 and the signal receiving unit 130 may be provided in the touch panel 200 or may be provided outside. In the case where such configurations are provided outside the touch panel 200, the touch panel 200 may mean a touch panel electrode 50.

The control unit 180 may control the configuration (s) included in the touch panel 200. [ For example, the control unit 180 may control the voltage supply unit 110 and the switch units 120a and 120b to supply a voltage to at least one of the TX electrode 51 and the RX electrode 52. [

The control unit 180 controls the signal receiving unit 130 to detect (detect) an electrical signal received from the stylus pen 20 through at least one of the TX electrode 51 and the RX electrode 52 after a predetermined time has elapsed And the switch units 120a and 120b.

The present invention can connect the voltage supply unit 110 to the TX electrode 51 as well as the RX electrode 52 and can supply the signal receiving unit 110 for processing the electrical signal received from the stylus pen 20 But also to the TX electrode 51 as well as the RX electrode 52.

Accordingly, the voltage supply unit 110 can supply not only the voltage to the TX electrode 51 but also the RX electrode 52, and the signal receiving unit 130 can supply not only the electric signal received from the RX electrode 52 The electric signal received from the TX electrode 51 can also be processed.

Hereinafter, the process of transmitting and receiving an electric signal between the touch panel 200 and the stylus pen 20 through the electrostatic capacitive coupling will be described in more detail with reference to FIG.

Fig. 4 shows the circuit configuration on the stylus side and the circuit configuration on the touch panel side where the capacitive coupling is generated.

The stylus pen may be provided with an LC circuit 22 for storing electrical signals (electric power, electrical energy) transmitted by capacitive coupling. The LC circuit 22 may transmit the stored electric signal to the touch panel 200.

If the circuit on the touch panel side is briefly displayed, the TX electrode 51 may include the resistance component R_tx of the TX electrode and the stray capacitance C_TXG of the TX electrode. The resistance component R_rx of the TX electrode and the stray capacitance C_RXG of the RX electrode may be included in the RX electrode 52.

The stray capacitances C_TXG and C_RXG may be referred to as parasitic capacitance and may be affected by the line width of the electrode lines. For example, the stray capacitance may increase as the line width increases.

In addition, the resistance component of the TX electrode and the RX electrode can be made smaller as the line width of the electrode line becomes larger.

On the other hand, mutual capacitance can be formed between the touch panel electrode 50 and the stylus pen by capacitive coupling. Specifically, a first mutual capacitance C_mY is formed between the LC circuit 22 of the stylus pen and the TX electrode 51 of the touch panel electrode 50, and the LC circuit 22 of the stylus pen and the touch panel electrode 50 may have a second mutual capacitance C_mX different from the first mutual capacitance.

4, when an AC voltage is applied to the TX electrode 51 from the voltage supply unit 110, the LC circuit 22 of the stylus pen 20 generates a first inter-capacitance (Electric signal) from the TX electrode 51 through the second electrode C_my. The LC circuit 22 that has received the power energy can start resonance and generate an electrical signal. The electric signal in the LC circuit 22 is a signal obtained by combining a component oscillating at a frequency equal to the frequency f_AC of the AC voltage (or a voltage supply (AC power supply) signal) and a component oscillating at the resonance frequency f_LC of the LC circuit 22 .

At this time, the voltage V_S, which is an electric signal of the LC circuit 22 of the stylus pen 20, can be defined as shown in Equation (1).

Here, A_1, A_2 and A_3 are proportional constants, and the electric parameters (LS, Cs, and C) of the coils and the capacitors constituting the LC circuit 22 and the frequency of the AC voltage and the LC resonance frequency ratio f_LC / f_AC Function. All of these are constant even as time changes.

The first term on the left side of Equation 1 is a signal that the LC circuit 22 of the stylus pen vibrates by receiving power energy (or AC power supply signal) from the TX electrode to which the AC voltage is applied, Means an LC resonance signal of the LC circuit 22 of the pen.

The expression exp (-A_3 * t) in the second term expresses that the signal of the second term attenuates over time, and only the signal which vibrates after receiving the AC power supply signal of the first term is left. Can be understood as an operation in a general LC resonant circuit.

Here, the LC resonance signal is attenuated because the vibration energy is consumed as thermal energy by the resistance component existing in the LC circuit 22.

On the other hand, when the preset time t_a elapses, the controller 180 can control the switch SW1 to stop the supply of the AC voltage to the TX full load. The predetermined time t_a is a time at which the supply of power energy from the TX electrode to the LC circuit 22 of the stylus pen 20 is judged to be equal to or larger than the reference amount, which is determined by the user's setting or controlled by the control unit Can be determined.

When the supply of the AC voltage to the TX electrode 51 is cut off (at t = t_a), the LC circuit 22 of the stylus pen receives the power energy (or AC power supply signal) from the TX electrode to which the AC voltage is applied The received oscillating signal is lost based on the interruption.

Further, the LC circuit 22 of the stylus pen exhibits an electric signal oscillating at the resonance frequency f_LC, which can be expressed by Equation (2).

The stylus pen 20 can supply an electric signal from the LC circuit 22 to the touch panel 200. The RX electrode 52 can detect (receive) the electrical signal supplied from the stylus pen 20 through the mutual capacitance C_mX formed by the electrostatic capacitive coupling.

The electric signal detected by the RX electrode 52 and transmitted to the signal receiving unit 130 may be expressed by Equation (3).

The meaning of V_RX] TX means an electric signal transmitted from the stylus pen 20 to the RX electrode 52 after power energy is transferred to the stylus pen 20 by the TX electrode 51.

The signal receiving unit 130 receiving the electric signal of Equation 3 detects at least one of the position of the stylus pen and the touch pressure based on the signal size of the electric signal, the frequency component and the phase included in the electric signal, can do.

The above description can be applied to the same or similar analogy when the AC voltage is supplied to the RX electrode 52 or when the TX electrode 51 receives the electric signal.

5 is a conceptual diagram for explaining a resonance frequency of a stylus pen according to an embodiment of the present invention.

The stylus pen 20 according to an embodiment of the present invention, which may include at least one of the components described above, may be configured to include a coil capacitance of the L element constituting the LC circuit 22, (LC resonance frequency) defined by the capacitance of? C. Further, the resonance frequency can be varied based on the change of the capacitance of? C.

Assuming that the above-mentioned? C is constant, the plurality of stylus pens 20 can be resonated at different resonance frequencies when the coil capacitances of the L elements constituting the LC circuit 22 and the electrostatic capacitances of the C elements are different.

5, the first stylus pen Pen 1 resonates at a resonance frequency f_1, the second stylus pen Pen 2 resonates at a resonance frequency f_2, the third stylus pen Pen 3 resonates at a resonance frequency f_2, Can resonate at the resonance frequency f_3.

The stylus pen 20 can receive power energy through the capacitive coupling with the touch panel to charge the LC circuit 22. [ At this time, when the stylus pen 20 receives the power energy having a frequency corresponding to the resonance frequency of the LC circuit 22, the charging speed (or the power energy reception rate, the power energy reception efficiency, and the power energy reception rate) It can be fast.

The frequency of the power energy (or electric signal) may correspond to the frequency of the voltage applied to the touch panel electrode 50 provided on the touch panel 200. For example, if the frequency of the voltage (AC voltage) applied to the TX electrode 51 is f_n, the frequency of the power energy transmitted (transmitted) to the stylus pen 20 through the capacitive coupling may be f_n .

In order for the power energy to be supplied (charged) at the highest efficiency (or speed) to the LC circuit 22 provided in the stylus pen 20 through the electrostatic capacitive coupling between the stylus pen 20 and the touch panel 200, A voltage having a frequency corresponding to the resonance frequency of the LC circuit 22 must be applied to the touch panel electrode 50. [

5, when a voltage having a frequency f1 is applied to the touch panel electrode 50 (for example, the TX electrode 51) provided on the touch panel 200, the resonance frequency f1 The first stylus pen Pen 1 resonating with the first stylus pen 1 can be supplied with the power energy of M1 per hour.

On the other hand, when a voltage having a frequency f1 is applied to the touch panel electrode 50, the second stylus pen Pen 2 resonates at a resonance frequency f2 different from the resonance frequency f1, Energy is supplied.

The third stylus Pen Pen resonating at a resonance frequency f3 having a difference larger than the resonance frequencies f1 and f2 with respect to the resonance frequency f1 is connected to the touch panel electrode 50 via a voltage Is applied, a power energy of M3, which is smaller than M2, is supplied per hour.

That is, when a voltage having a frequency f1 is applied to the touch panel electrode 50, the electric energy (or signal, electric signal) transmitted to the stylus pen 20 via the electrostatic capacitive coupling is applied to the stylus pen 20 When the resonance frequency of the provided LC circuit 22 is f1, a maximum amount of power energy is supplied per time, and as the resonance frequency increases to f1, the amount of power energy delivered per hour decreases.

Therefore, when various kinds of stylus pens approach (or touch) the touch panel 200, the power energy can be supplied to the stylus pens 20).

The mobile terminal 10 associated with the present invention can control the touch panel in a variety of ways to supply power energy to the stylus pen 20 via capacitive coupling in an optimized manner.

FIG. 6 is a flow chart for explaining a typical control method of the present invention, and FIG. 7 is a conceptual diagram for explaining a control method shown in FIG.

Referring to FIG. 6, in the present invention, a step of applying a plurality of voltages having different frequencies to the touch panel is performed (S610).

Specifically, the control unit 180 can apply a plurality of voltages having different frequencies to the plurality of touch panel electrodes 50 provided on the touch panel. The reason why the plurality of voltages having different frequencies are applied to the touch panel is that it does not know the resonance frequency of the stylus pen 20 (that is, the resonance frequency of the LC circuit 22 provided in the stylus pen 20) .

For convenience of explanation, a voltage is applied to the plurality of TX electrodes 51 of the plurality of touch panel electrodes 50, and an electrical signal received from the stylus pen through the plurality of RX electrodes 52 is detected Sensing, and sensing).

The control unit 180 can apply a plurality of voltages having different frequencies to the touch panel (i.e., the plurality of TX electrodes 52) so that an electrical signal is transmitted through the electrostatic capacitive coupling to the stylus pen 20. [ have.

At this time, the different frequencies may be n voltages having frequencies of f1 to fn, as shown in Fig. 7 (a). The f1 to fn may be different from each other.

The mobile terminal 10 according to the present invention may include a voltage supply unit 110 for generating a plurality of voltages having different frequencies, as shown in FIG. 7 (a). That is, the voltage supplier 110 may include a plurality of AC power sources for generating a plurality of voltages having different frequencies.

However, the present invention is not limited thereto, and the voltage supply unit 110 may be provided with a variable AC power source capable of changing the frequency.

Thereafter, the touch panel of the present invention performs a step of receiving an electric signal from the stylus pen 20 (supplied with power energy) charged by the touch panel to which a plurality of voltages having different frequencies are applied (S620 ).

More specifically, the stylus pen 20 related to the present invention is a stylus pen 20 having a frequency corresponding to the resonance frequency of the LC circuit of the stylus pen 20 (or a frequency ) Can be supplied through the capacitive coupling.

For example, when the resonance frequency f_pen of the stylus pen 20 (LC circuit 22) corresponds to f1 of the different frequencies f1 to fn, the LC circuit 22 of the stylus pen 20 calculates Lt; RTI ID = 0.0 > f1. &Lt; / RTI >

If there is no frequency corresponding to the resonance frequency f_pen among the different frequencies f1 to fn, the LC circuit 22 of the stylus pen 20 is controlled by a voltage having a frequency closest to the f_pen among f1 to fn And can be charged using the generated power energy.

As shown in Fig. 7 (b), the stylus pen 20 filled with the electric energy can transmit an electric signal having the resonance frequency f_pen of the LC circuit 22. [ In this case, the controller 180 can receive (or detect, sense, and sense) the electric signal transmitted from the stylus pen 20 through the RX electrode 52 of the touch panel 200.

Thereafter, in the present invention, a step of determining a frequency of the received electric signal and applying a voltage having a determined frequency to the touch panel is performed (S630).

Specifically, the control unit 180 (or the signal receiving unit 130) detects an electrical signal transmitted from the stylus pen 20 through a touch panel electrode (for example, an RX electrode) The frequency of the signal can be determined (judged, analyzed).

The frequency of the electric signal may correspond to the resonance frequency f_pen of the LC circuit 22 of the stylus pen 20.

The control unit 180 then supplies a voltage having the frequency f_pen of the received electric signal to a touch panel (specifically, a plurality of TX electrodes), instead of the plurality of voltages (i.e., a plurality of voltages having different frequencies f1 to fn) (At least one of them).

7 (b), when the electrical signal having the resonance frequency f_pen is received from the stylus pen 20, the control unit 180 (or the signal receiving unit 130) The frequency f_pen of the electric signal can be determined.

7 (c), the control unit 180 outputs a voltage having the frequency f_pen of the received electric signal instead of the plurality of voltages having the different frequencies to the touch panel (TX electrode)).

In this case, the present invention can transmit and receive an electric signal between the stylus pen and the touch panel at the maximum efficiency using the minimum voltage (i.e., one voltage having the resonance frequency of the stylus pen).

On the other hand, in the stylus pen 20 related to the present invention, when pressure is applied to the touch panel by an external force (or user), the variable capacitor provided in the LC circuit 22 can be changed. Accordingly, the resonance frequency of the electric signal transmitted from the stylus pen can be changed based on the pressure of the stylus pen.

In this case, the control unit 180 (or the signal receiving unit 130) can determine the changed frequency when the frequency of the electric signal received from the stylus pen 20 is changed. Then, the control unit 180 may apply the voltage having the changed frequency to the touch panel (the touch panel electrode 50 (the TX electrode 51)).

For example, in the state where a voltage having the first resonance frequency is applied to the touch panel based on reception of an electric signal having the first resonance frequency (f_pen1) from the stylus pen, The electrical signal may be changed to a second resonance frequency f_pen2 different from the first resonance frequency. In this case, the control unit 180 detects (determines) the changed frequency (second resonant frequency f_pen2) and outputs a voltage having the changed frequency (second resonant frequency f_pen2) to the touch panel 50) (the TX electrode 51)).

According to the present invention, in the present invention, a plurality of voltages having different frequencies are applied to charge the stylus pen that does not know the resonance frequency, and the resonance frequency of the stylus pen is determined based on the electric signal received from the charged stylus pen . Further, in the present invention, when the resonance frequency of the stylus pen is determined, only a voltage having a resonance frequency determined in place of a plurality of voltages having different frequencies may be applied to the touch panel so as to transmit and receive an electric signal with the stylus pen with optimized efficiency . In addition, since the present invention drives only a single voltage having a resonance frequency while driving a plurality of voltages, power consumption can be significantly reduced.

Hereinafter, various embodiments of the present invention related to step S610 will be described in more detail.

The control unit 180 can apply a plurality of voltages having different frequencies to the touch panel 200 (specifically, the touch panel electrode (TX electrode)) based on the satisfaction of predetermined conditions.

For example, the control unit 180 may supply a plurality of voltages having different frequencies to the touch panel 200 based on whether the human body (e.g., a finger) or the stylus pen touches (or contacts) .

The control unit 180 controls the stylus pen 20 to move the stylus pen 20 within a range of a distance (or a predetermined distance) at which the stylus pen 20 can transmit and receive an electric signal with the touch panel 200 To the touch panel 200. [0051] FIG.

The distance at which the electrical signal can be transmitted and received may be a distance at which the magnitude of the electrical signal transmitted and received between the touch panel 200 and the stylus pen 20 through the capacitive coupling is greater than or equal to a threshold value. The size of the electrical signal may increase as the distance between the touch panel 200 and the stylus pen 20 approaches.

According to the present invention, it is possible to determine (determine and detect) that the stylus pen 20 has entered a distance that allows the stylus pen 20 to transmit and receive electric signals to and from the touch panel 200 in various ways.

For example, the control unit 180 may apply a specific voltage periodically (or always) to the touch panel electrode 50 to determine the entry. Accordingly, the touch panel electrode 50 may have a specific capacitance. At this time, when the stylus pen 20 enters within the above distance, the specific capacitance can be changed. The control unit 180 may determine that the stylus pen 20 has reached the distance based on the change in the specific capacitance.

As another example, the stylus pen 20 associated with the present invention may periodically (or always, or by user control) send out a specific electrical signal. When the specific electric signal is received from the stylus pen 20 through the touch panel 200 (for example, the RX electrode 52), the controller 180 determines that the stylus pen 20 has reached the distance It can be judged.

In another example, the mobile terminal 100 related to the present invention may be configured such that the stylus pen 20 is moved from the touch panel 200 to the distance (or the electric wire) from the touch panel 200 through a sensing unit (for example, an infrared sensor, A predetermined distance to a distance at which it is possible to transmit and receive a signal).

In addition, the mobile terminal related to the present invention can determine that the stylus pen 20 is proximate (or approach, contact, etc.) from the touch panel 200 in various ways.

Meanwhile, the controller 180 of the mobile terminal 100 according to the present invention can apply a plurality of voltages having different frequencies to a touch panel (for example, a plurality of TX electrodes) in various manners.

For example, the controller 180 may sequentially apply a plurality of voltages having different frequencies to the touch panel. This allows a plurality of voltages having different frequencies to be applied to the plurality of TX electrodes 51 provided on the touch panel according to the passage of time. That is, the control unit 180 can apply a voltage having the frequency f1 to the plurality of TX electrodes at time t1 and a voltage having the frequency f2 at the time t2 to the plurality of TX electrodes.

On the other hand, when the electric signal is received from the stylus pen 20 during the sequential application of a plurality of voltages having different frequencies, the control unit 180 can stop the application of the plurality of voltages. Thereafter, the controller 180 may determine the frequency of the received electrical signal and apply a voltage having a determined frequency to the plurality of TX electrodes.

As another example, the control unit 180 may simultaneously apply at least two voltages among a plurality of voltages having different frequencies to the touch panel. That is, the control unit may simultaneously apply at least two voltages among a plurality of voltages having different frequencies f1 to fn to the plurality of TX electrodes. At this time, the controller 180 may apply at least two voltages having the selected frequencies to the plurality of TX electrodes so that the interference (or overlap) of the voltage applied to the TX electrode is minimized. The at least two voltages may be determined by user setting.

As another example, the controller 180 may apply a plurality of voltages having different frequencies to a plurality of TX electrodes, respectively. For example, the control unit 180 applies a voltage having a first frequency f1 among the plurality of voltages to the first TX electrode of the plurality of TX electrodes, and, of the plurality of voltages, A voltage having a second frequency f2 may be applied to the second TX electrode different from the first TX electrode among the plurality of TX electrodes.

In this case, one voltage having a different frequency may be applied to each of the plurality of TX electrodes.

If an electric signal is not received through the plurality of RX electrodes for a predetermined time after the application of the plurality of voltages, the control unit 180 supplies a voltage having a frequency different from the frequency of the voltage applied to each of the plurality of TX electrodes The plurality of voltages may be applied to the TX electrode.

Here, the fact that the electric signal is not received may mean that the magnitude of the electric signal received from the stylus pen is smaller than a preset threshold value.

Specifically, when the resonance frequency f_pen of the stylus pen corresponds to the frequency f1 and the voltage having the frequency f1 of the stylus pen 20 is spaced apart from the applied first TX electrode by a certain distance (for example, The stylus pen 20 may not receive power energy from the touch panel (i.e., the nth TX electrode) when the stylus pen 20 is positioned around the nth TX electrode to which the voltage is applied.

In this case, the controller 180 applies a voltage having the frequency f1 to the n-th TX electrode and applies a voltage having the frequency fn to the (n-1) th TX electrode to generate a plurality of voltages having different frequencies And can be applied to each of a plurality of TX electrodes.

That is, the voltage having the frequency f1 can be sequentially applied to the first TX electrode, the second TX electrode, and the third TX electrode in accordance with the elapse of time, and the voltage having the frequency f2 can be applied to the second TX electrode, A TX electrode, and a fourth TX electrode sequentially in accordance with the passage of time.

In this manner, a plurality of voltages having different frequencies f1 to fn can be sequentially applied to the plurality of TX electrodes sequentially in accordance with the passage of time.

In this process, when an electrical signal is received from the stylus pen, the controller 180 stops applying a plurality of voltages and applies only a voltage having a frequency of the received electrical signal to at least one of the plurality of TX electrodes.

As described above, according to the present invention, a plurality of voltages having different frequencies are applied to a touch panel to charge the stylus pen with electrical energy, and when an electrical signal is received from the stylus pen, A voltage having a frequency of a signal can be applied to the touch panel. Accordingly, by applying a voltage having a resonance frequency of the stylus pen to the touch panel, the electrical signal transmission / reception ratio between the touch panel and the stylus pen can be remarkably improved.

The present invention described above can be embodied as computer-readable codes on a medium on which a program is recorded. The computer readable medium includes all kinds of recording devices in which data that can be read by a computer system is stored. Examples of the computer readable medium include a hard disk drive (HDD), a solid state disk (SSD), a silicon disk drive (SDD), a ROM, a RAM, a CD-ROM, a magnetic tape, a floppy disk, , And may also be implemented in the form of a carrier wave (e.g., transmission over the Internet). Also, the computer may include a control unit 180 of the terminal. Accordingly, the above description should not be construed in a limiting sense in all respects and should be considered illustrative. The scope of the present invention should be determined by rational interpretation of the appended claims, and all changes within the scope of equivalents of the present invention are included in the scope of the present invention.

Claims

1. A mobile terminal provided with a stylus pen,
A touch panel having a plurality of touch panel electrodes;
A stylus pen formed to transmit and receive an electric signal with the touch panel using a capacitive coupling; And
A plurality of voltages having different frequencies are applied to the touch panel so that an electric signal is transmitted through the capacitive coupling with the stylus pen, and when an electrical signal is received from the stylus pen, And a controller for applying to the touch panel only a voltage having a frequency of the received electric signal instead of a plurality of voltages having different frequencies so that an electric signal transmission /
The touch panel includes:
A plurality of TX electrodes; And
And a plurality of RX electrodes arranged to cross the TX electrodes,
Wherein,
Applying a voltage having a first frequency among the plurality of voltages to a first one of the plurality of TX electrodes,
And applies a voltage having a second frequency different from the first frequency among the plurality of voltages to the second TX electrode different from the first TX electrode among the plurality of TX electrodes.

The method according to claim 1,
Wherein,
And sequentially applies the plurality of voltages to the touch panel.

The method according to claim 1,
Wherein,
Wherein at least two voltages among the plurality of voltages are simultaneously applied to the touch panel.

delete

The method according to claim 1,
Wherein,
Wherein when a voltage having a frequency different from a frequency of a voltage applied to each of the plurality of TX electrodes is applied to the plurality of TX electrodes when the electrical signals are not received through the plurality of RX electrodes for a predetermined time after the application of the plurality of voltages, To the TX electrode. &Lt; Desc / Clms Page number 19 >

The method according to claim 1,
The frequency of the electric signal transmitted from the stylus pen can be changed based on the pressure of the stylus pen,
Wherein,
And when the frequency of the received electric signal changes, applies a voltage having a changed frequency to the touch panel.

A method for controlling a mobile terminal equipped with a stylus pen,
Applying a plurality of voltages having different frequencies to a touch panel;
Receiving an electrical signal from a charged stylus pen through an electrostatic capacitive coupling with the touch panel; And
And a controller for controlling the touch panel based on the determined frequency so as to determine a frequency of the received electric signal and to transmit and receive an electrical signal between the stylus pen and the touch panel, The method comprising:
The touch panel includes:
A plurality of TX electrodes; And
And a plurality of RX electrodes arranged to cross the TX electrodes,
Wherein the step of applying a plurality of voltages having different frequencies to the touch panel comprises:
Applying a voltage having a first frequency among the plurality of voltages to a first one of the plurality of TX electrodes,
And applying a voltage having a second frequency different from the first frequency among the plurality of voltages to a second TX electrode different from the first TX electrode among the plurality of TX electrodes.