WO2019245255A1 - Method for cancelling common mode noise of touch input device and touch input device implemented by same method - Google Patents

Abstract

A method for cancelling common mode noise of a touch input device for detecting a touch pressure by using a plurality of pressure sensors according to an embodiment of the present invention may comprise the steps of: determining a touch location where the touch pressure is applied to the touch input device; acquiring current signal measurement values from the plurality of pressure sensors driven by the touch pressure at the touch location; acquiring, from the plurality of pressure sensors, reference signal measurement values corresponding to the touch location; and cancelling the common mode noise generated by the plurality of pressure sensors, using an average value of the current signal measurement values and an average value of the reference signal measurement values.

Description

Common Mode Noise Reduction Method of Touch Input Device and Touch Input Device Implemented in Same Method

The present invention relates to a method for removing common mode noise of a touch input device and a touch input device implemented by the same method. More specifically, the present invention relates to a touch input for removing common mode noise generated when a touch pressure is applied to the touch input device. The present invention relates to a common mode noise canceling method and a touch input device implemented in the same method.

Various types of input devices are used for the operation of the computing system. For example, input devices such as buttons, keys, joysticks, and touch screens are used. Due to the easy and simple operation of the touch screen, the use of the touch screen is increasing in the operation of the computing system.

The touch screen may constitute a touch surface of a touch input device that includes a touch sensor panel, which may be a transparent panel having a touch-sensitive surface. Such a touch sensor panel may be attached to the front of the display screen such that the touch-sensitive surface covers the visible side of the display screen. By simply touching the touch screen with a finger or the like, the user can operate the computing system. In general, a computing system may recognize a touch and a touch location on a touch screen and interpret the touch to perform computation accordingly.

Meanwhile, a touch input device capable of detecting not only the touch position according to the touch on the touch screen but also the pressure magnitude of the touch has been released.

However, a common mode noise is generated in the touch pressure detection process, and thus, an accurate amount of touch pressure is difficult to detect.

The present invention has been made to solve the above problems, and an object thereof is to provide a method for removing common mode noise generated during a touch pressure detection process.

The common mode noise removing method of the touch input device for detecting the touch pressure by using a plurality of pressure sensors according to an embodiment of the present invention is to determine the touch position to which the touch pressure is applied to the touch input device. Determining, obtaining a present signal measurement value from the plurality of pressure sensors driven by the touch pressure at the touch position, obtaining a reference signal measurement value corresponding to the touch position from the plurality of pressure sensors; And removing the common mode noise generated from the plurality of pressure sensors by using the average value of the current signal measurement value and the average value of the reference signal measurement value.

According to another aspect of the present invention, a touch input device includes a plurality of pressure sensors for detecting a touch pressure applied to a touch input device, a touch sensor for detecting a touch position to which the touch pressure is applied, and the plurality of pressure sensors. And a controller for controlling the plurality of pressure sensors and the touch sensor to remove common mode noise generated from the controller.

A positioning unit which determines the touch position to which the touch pressure is applied, obtains a current signal measurement value from the plurality of pressure sensors driven by the touch pressure at the touch position, and provides the touch position to the touch position from the plurality of pressure sensors. Noise canceling for removing the common mode noise generated from the plurality of pressure sensors using a signal measurement value acquisition unit for obtaining a corresponding reference signal measurement value and an average value of the current signal measurement value and the average value of the reference signal measurement value. It may include wealth.

According to an embodiment of the present invention, the common mode noise generated when the pressure is applied to the touch input device can be removed.

According to an embodiment of the present invention, random noise generated when pressing the touch input device can be reduced.

1A and 1B are schematic diagrams of a capacitive touch sensor included in a touch input device according to an embodiment of the present invention, and a configuration for an operation thereof.

2 illustrates a control block for controlling touch position, touch pressure, and display operation in a touch input device according to an embodiment of the present invention.

3A to 3B are conceptual views illustrating a configuration of a display module in a touch input device according to an embodiment of the present invention.

4A is a perspective view of a touch input device according to an embodiment of the present invention.

4B to 4G are plan views of the touch input device according to the embodiment of the present invention.

5 illustrates a cross section of a sensor sheet according to an embodiment of the invention.

6A to 6C are cross-sectional views illustrating embodiments of a pressure sensor directly formed on various display panels of a touch input device according to an embodiment of the present invention.

7A to 7D are views illustrating shapes of various sensors included in the touch input device according to the embodiment of the present invention.

8 is a detailed block diagram of a controller of a touch input device according to an embodiment of the present invention.

9 is a flowchart illustrating a method for removing common mode noise of a touch input device according to an exemplary embodiment of the present invention.

DETAILED DESCRIPTION The following detailed description of the invention refers to the accompanying drawings that show, by way of illustration, specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. It should be understood that the various embodiments of the present invention are different but need not be mutually exclusive. For example, certain shapes, structures, and characteristics described herein may be embodied in other embodiments without departing from the spirit and scope of the invention with respect to one embodiment. In addition, it is to be understood that the location or arrangement of individual components within each disclosed embodiment may be changed without departing from the spirit and scope of the invention. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present invention, if properly described, is defined only by the appended claims, along with the full range of equivalents to which such claims are entitled. Like reference numerals in the drawings refer to the same or similar functions throughout the several aspects.

Hereinafter, a touch input device according to an embodiment of the present invention will be described with reference to the accompanying drawings. Hereinafter, the capacitive touch input device 1000 is illustrated, but the present invention may be applied to the touch input device 1000 that detects the touch position and / or the touch pressure in an arbitrary manner.

1A is a schematic diagram of a capacitive touch sensor 10 included in the touch input device 1000 according to an embodiment of the present invention, and a configuration for its operation. Referring to FIG. 1A, the touch sensor 10 includes a plurality of driving electrodes TX1 to TXn and a plurality of receiving electrodes RX1 to RXm, and a plurality of driving electrodes for operation of the touch sensor 10. Touch by receiving a detection signal including information on the capacitance change according to the touch on the touch surface from the driving unit 12 for applying a driving signal to the TX1 to TXn, and the plurality of receiving electrodes (RX1 to RXm) And a detector 11 for detecting a touch position.

As illustrated in FIG. 1A, the touch sensor 10 may include a plurality of driving electrodes TX1 to TXn and a plurality of receiving electrodes RX1 to RXm. In FIG. 1A, although the plurality of driving electrodes TX1 to TXn and the plurality of receiving electrodes RX1 to RXm of the touch sensor 10 form an orthogonal array, the present invention is not limited thereto. The electrodes TX1 to TXn and the plurality of receiving electrodes RX1 to RXm may have any number of dimensions and application arrangements thereof, including diagonal, concentric circles, and three-dimensional random arrangements. Here, n and m are positive integers and may have the same or different values, and may vary in size according to embodiments.

The plurality of driving electrodes TX1 to TXn and the plurality of receiving electrodes RX1 to RXm may be arranged to cross each other. The driving electrode TX includes a plurality of driving electrodes TX1 to TXn extending in the first axis direction, and the receiving electrode RX includes a plurality of receiving electrodes extending in the second axis direction crossing the first axis direction. RX1 to RXm).

As shown in FIGS. 7A and 7B, in the touch sensor 10 according to the exemplary embodiment of the present invention, the plurality of driving electrodes TX1 to TXn and the plurality of receiving electrodes RX1 to RXm may be formed on the same layer. Can be. For example, the plurality of driving electrodes TX1 to TXn and the plurality of receiving electrodes RX1 to RXm may be formed on an upper surface of the display panel 200A, which will be described later.

In addition, as shown in FIG. 7C, the plurality of driving electrodes TX1 to TXn and the plurality of receiving electrodes RX1 to RXm may be formed on different layers. For example, any one of the plurality of driving electrodes TX1 to TXn and the receiving electrodes RX1 to RXm is formed on the upper surface of the display panel 200A, and the other one is formed on the lower surface of the cover to be described later or the display panel. It may be formed inside the 200A.

The plurality of driving electrodes TX1 to TXn and the plurality of receiving electrodes RX1 to RXm may be formed of a transparent conductive material (for example, indium tin oxide (ITO) or ATO made of tin oxide (SnO 2) and indium oxide (In 2 O 3)). (Antimony Tin Oxide)) and the like. However, this is only an example and the driving electrode TX and the receiving electrode RX may be formed of another transparent conductive material or an opaque conductive material. For example, the driving electrode TX and the receiving electrode RX may include at least one of silver ink, copper, silver silver, and carbon nanotubes (CNT). Can be. In addition, the driving electrode TX and the receiving electrode RX may be implemented with a metal mesh.

The driving unit 12 according to the exemplary embodiment of the present invention may apply a driving signal to the driving electrodes TX1 to TXn. In an embodiment of the present invention, the driving signal may be applied to one driving electrode at a time from the first driving electrode TX1 to the nth driving electrode TXn in sequence. The driving signal may be repeatedly applied again. This is merely an example, and a driving signal may be simultaneously applied to a plurality of driving electrodes in some embodiments.

The sensing unit 11 provides information about the capacitance Cm 14 generated between the driving electrodes TX1 to TXn to which the driving signal is applied and the receiving electrodes RX1 to RXm through the receiving electrodes RX1 to RXm. By receiving a sensing signal that includes a touch can detect whether the touch position. For example, the sensing signal may be a signal in which the driving signal applied to the driving electrode TX is coupled by the capacitance Cm 14 generated between the driving electrode TX and the receiving electrode RX. As described above, a process of sensing the driving signals applied from the first driving electrode TX1 to the nth driving electrode TXn through the receiving electrodes RX1 to RXm may be referred to as scanning the touch sensor 10. Can be.

For example, the detector 11 may include a receiver (not shown) connected to each of the reception electrodes RX1 to RXm through a switch. The switch is turned on in a time interval for detecting the signal of the corresponding receiving electrode RX, so that the detection signal from the receiving electrode RX can be detected at the receiver. The receiver may comprise an amplifier (not shown) and a feedback capacitor coupled between the negative input terminal of the amplifier and the output terminal of the amplifier, i.e., in the feedback path. At this time, the positive input terminal of the amplifier may be connected to ground. In addition, the receiver may further include a reset switch connected in parallel with the feedback capacitor. The reset switch may reset the conversion from current to voltage performed by the receiver. The negative input terminal of the amplifier may be connected to the corresponding receiving electrode RX to receive a current signal including information on the capacitance Cm 14, and then integrate and convert the current signal into a voltage. The sensor 11 may further include an analog to digital converter (ADC) for converting data integrated through a receiver into digital data. Subsequently, the digital data may be input to a processor (not shown) and processed to obtain touch information about the touch sensor 10. In addition to the receiver, the detector 11 may include an ADC and a processor.

The controller 13 may perform a function of controlling the operations of the driver 12 and the detector 11. For example, the controller 13 may generate a driving control signal and transmit the driving control signal to the driving unit 12 so that the driving signal is applied to the predetermined driving electrode TX at a predetermined time. In addition, the control unit 13 generates a detection control signal and transmits the detection control signal to the detection unit 11 so that the detection unit 11 receives a detection signal from a predetermined reception electrode RX at a predetermined time to perform a preset function. can do.

In FIG. 1A, the driver 12 and the detector 11 may configure a touch detection device (not shown) capable of detecting whether the touch sensor 10 is touched and the touch position. The touch detection apparatus may further include a controller 13. The touch detection device may be integrated and implemented on a touch sensing integrated circuit (IC) corresponding to the touch sensor controller 1100, which will be described later, in the touch input device 1000 including the touch sensor 10. The driving electrode TX and the receiving electrode RX included in the touch sensor 10 are included in the touch sensing IC through, for example, conductive traces and / or conductive patterns printed on a circuit board. It may be connected to the driving unit 12 and the sensing unit 11. The touch sensing IC may be located on a circuit board on which a conductive pattern is printed, such as a touch circuit board (hereinafter referred to as a touch PCB). According to an exemplary embodiment, the touch sensing IC may be mounted on a main board for operating the touch input device 1000.

As described above, a capacitance Cm having a predetermined value is generated at each intersection point of the driving electrode TX and the receiving electrode RX, and such capacitance when an object such as a finger approaches the touch sensor 10. The value of can be changed. In FIG. 1A, the capacitance may represent mutual capacitance (Cm). The electrical characteristics may be detected by the sensing unit 11 to detect whether the touch sensor 10 is touched and / or the touch position. For example, the touch and / or the position of the touch on the surface of the touch sensor 10 formed of the two-dimensional plane including the first axis and the second axis may be sensed.

More specifically, when the touch on the touch sensor 10 occurs, the position of the touch in the second axis direction may be detected by detecting the driving electrode TX to which the driving signal is applied. Similarly, the position of the touch in the first axis direction can be detected by detecting a change in capacitance from the received signal received through the receiving electrode RX when the touch sensor 10 is touched.

In the above, the operation method of the touch sensor 10 that detects the touch position has been described based on the mutual capacitance change amount between the driving electrode TX and the receiving electrode RX, but the present invention is not limited thereto. That is, as illustrated in FIG. 1B, the touch position may be sensed based on the amount of change in the self capacitance.

1B is a schematic diagram illustrating another capacitive touch sensor 10 included in the touch input device 1000 and an operation thereof according to another embodiment of the present invention. The touch sensor 10 illustrated in FIG. 1B includes a plurality of touch electrodes 30. As illustrated in FIG. 5D, the plurality of touch electrodes 30 may be disposed in a lattice shape at regular intervals, but is not limited thereto.

The driving control signal generated by the control unit 13 is transmitted to the driving unit 12, and the driving unit 12 applies the driving signal to the preset touch electrode 30 at a predetermined time based on the driving control signal. In addition, the sensing control signal generated by the controller 13 is transmitted to the sensing unit 11, and the sensing unit 11 receives the sensing signal from the touch electrode 30 preset at a predetermined time based on the sensing control signal. Receive input. In this case, the detection signal may be a signal for the change amount of the magnetic capacitance formed in the touch electrode 30.

At this time, whether the touch on the touch sensor 10 and / or the touch position is detected by the sensing signal detected by the sensing unit 11. For example, since the coordinates of the touch electrode 30 are known in advance, it is possible to detect whether the object touches the surface of the touch sensor 10 and / or its position.

In the above description, for convenience, the driving unit 12 and the sensing unit 11 are described as being divided into separate blocks, but the driving signal is applied to the touch electrode 30 and the sensing signal is input from the touch electrode 30. It is also possible to perform in one driving and sensing unit.

Although the capacitive touch sensor panel has been described in detail as the touch sensor 10, the touch sensor 10 for detecting whether or not a touch is detected in the touch input device 1000 according to an embodiment of the present invention Surface capacitive, projected capacitive, resistive, SAW (surface acoustic wave), infrared, optical imaging, and distributed signals other than those described above It can be implemented using any touch sensing scheme such as dispersive signal technology and acoustic pulse recognition scheme.

2 illustrates a control block for controlling a touch position, a touch pressure, and a display operation in the touch input device 1000 according to an embodiment of the present invention. In addition to the display function and the touch position detection, in the touch input device 1000 configured to detect the touch pressure, the control block includes a touch sensor controller 1100 for detecting the aforementioned touch position and a display controller for driving the display panel. 1200 and a pressure sensor controller 1300 for detecting pressure. The display controller 1200 receives input from a central processing unit (CPU), an application processor (AP), or the like, which is a central processing unit on a main board for operating the touch input device 1000, to the display panel 200A. It may include a control circuit to display the desired content. Such a control circuit may be mounted on a display circuit board (hereinafter referred to as display PCB). Such control circuits may include display panel control ICs, graphic controller ICs, and other circuits necessary for operating the display panel 200A.

The pressure sensor controller 1300 for detecting pressure through the pressure sensor 450 may be configured similarly to the configuration of the touch sensor controller 1100 to operate similarly to the touch sensor controller 1100. In detail, the pressure sensor controller 1300 may include a driver, a detector, and a controller, as illustrated in FIGS. 1A and 1B, and detect the magnitude of the pressure by a detection signal detected by the detector. In this case, the pressure sensor controller 1300 may be mounted on the touch PCB in which the touch sensor controller 1100 is mounted, or may be mounted on the FPCB in which the display controller 1200 is mounted.

According to an embodiment, the touch sensor controller 1100, the display controller 1200, and the pressure sensor controller 1300 may be included in the touch input device 1000 as different components. For example, the touch sensor controller 1100, the display controller 1200, and the pressure sensor controller 1300 may be configured with different chips. In this case, the processor 1500 of the touch input device 1000 may function as a host processor for the touch sensor controller 1100, the display controller 1200, and the pressure sensor controller 1300.

The touch input device 1000 according to the embodiment of the present invention may be a cell phone, a personal data assistant (PDA), a smartphone, a tablet PC, an MP3 player, a notebook, or the like. It may include an electronic device including the same display screen and / or a touch screen.

In order to manufacture such a touch input device 1000 in a slim and light weight, the touch sensor controller 1100, the display controller 1200, and the pressure sensor controller 1300, which are separately configured as described above, are manufactured. Can be integrated into one or more configurations, depending on the embodiment. In addition, each of these controllers may be integrated into the processor 1500. In addition, the touch sensor 10 may be integrated into the display panel 200A according to an exemplary embodiment.

In the touch input device 1000 according to the exemplary embodiment, the touch sensor 10 for detecting a touch position may be located outside or inside the display panel 200A. The display panel 200A of the touch input device 1000 according to the embodiment is included in a liquid crystal display (LCD), a plasma display panel (PDP), an organic light emitting diode (OLED), and the like. It may be a display panel. Accordingly, the user may perform an input operation by performing a touch on the touch surface while visually confirming the screen displayed on the display panel.

3A and 3B are conceptual views illustrating the configuration of the display module 200 in the touch input device 1000 according to the present invention. First, a configuration of a display module 200 including a display panel 200A using an LCD panel will be described with reference to FIG. 3A.

As shown in FIG. 3A, the display module 200 includes a display panel 200A, which is an LCD panel, a first polarization layer 271 disposed on the display panel 200A, and a display panel 200A disposed below the display panel 200A. The polarizing layer 272 may be included. In addition, the display panel 200A, which is an LCD panel, includes a liquid crystal layer 250 including a liquid crystal cell, a first substrate layer 261 and a liquid crystal layer 250 disposed on the liquid crystal layer 250. It may include a second substrate layer 262 disposed under the. In this case, the first substrate layer 261 may be a color filter glass, and the second substrate layer 262 may be a TFT glass. In some embodiments, at least one of the first substrate layer 261 and the second substrate layer 262 may be formed of a bendable material such as plastic. In FIG. 3A, the second substrate layer 262 is formed of various layers including a data line, a gate line, a TFT, a common electrode (Vcom), a pixel electrode, and the like. Can be done. These electrical components can operate to produce a controlled electric field to orient the liquid crystals located in the liquid crystal layer 250.

Next, a configuration of the display module 200 including the display panel 200A using the OLED panel will be described with reference to FIG. 3B.

As shown in FIG. 3B, the display module 200 may include a display panel 200A, which is an OLED panel, and a first polarization layer 282 disposed on the display panel 200A. In addition, the display panel 200A, which is an OLED panel, has an organic layer 280 including an organic light-emitting diode (OLED), a first substrate layer 281 disposed above the organic layer 280, and a lower portion of the organic layer 280. The second substrate layer 283 may be disposed. In this case, the first substrate layer 281 may be encapsulation glass, and the second substrate layer 283 may be TFT glass. In some embodiments, at least one of the first substrate layer 281 and the second substrate layer 283 may be formed of a bendable material such as plastic. The OLED panel may include an electrode used to drive the display panel 200A such as a gate line, a data line, a first power line ELVDD, and a second power line ELVSS. OLED (Organic Light-Emitting Diode) panel is a self-luminous display panel using the principle that light is generated when electrons and holes combine in the organic material layer when electric current flows in the fluorescent or phosphorescent organic thin film. Determine the color

Specifically, OLED uses a principle that the organic material emits light when the organic material is applied to glass or plastic to flow electricity. In other words, when holes and electrons are injected into the anode and cathode of the organic material and recombined in the emission layer, excitation is formed in a high energy state. Is to use the generated principle. At this time, the color of light varies according to the organic material of the light emitting layer.

OLED is composed of line-driven passive-matrix organic light-emitting diode (PM-OLED) and individual-driven active-matrix organic light-emitting diode (AM-OLED) depending on the operating characteristics of the pixels constituting the pixel matrix. exist. Since both require no backlight, the display module can be made very thin, the contrast ratio is constant according to the angle, and color reproducibility with temperature is good. In addition, undriven pixels are very economical in that they do not consume power.

In operation, the PM-OLED emits light only during a scanning time at a high current, and the AM-OLED maintains light emission during a frame time at a low current. Therefore, the AM-OLED has the advantages of better resolution, greater area display panel driving, and lower power consumption than PM-OLED. In addition, each device can be individually controlled by embedding a thin film transistor (TFT), so it is easy to realize a sophisticated screen.

In addition, the organic material layer 280 may include a HIL (Hole Injection Layer), a HTL (Hole Transfer Layer), an EIL (Emission Material Layer), an ETL (Electron Transfer Layer), and an EML. (Electron Injection Layer, light emitting layer) may be included.

Briefly described for each layer, HIL injects holes, using a material such as CuPc. HTL functions to move the injected holes, and mainly uses materials having good hole mobility. As the HTL, arylamine, TPD and the like can be used. EIL and ETL are layers for the injection and transport of electrons, and the injected electrons and holes combine and emit light in the EML. EML is a material expressing the color emitted, and is composed of a host that determines the lifetime of the organic material and a dopant that determines the color and efficiency. This is merely to describe the basic configuration of the organic material layer 280 included in the OLED panel, the present invention is not limited to the layer structure or material of the organic material layer 280.

The organic layer 280 is inserted between an anode (not shown) and a cathode (not shown). When the TFT is turned on, a driving current is applied to the anode to inject holes, and the cathode is injected into the cathode. Electrons are injected, and holes and electrons move to the organic layer 280 to emit light.

It will be apparent to those skilled in the art that the LCD panel or OLED panel may further include other configurations and may be modified to perform display functions.

The display module 200 of the touch input device 1000 according to the present invention may include a configuration for driving the display panel 200A and the display panel 200A. Specifically, when the display panel 200A is an LCD panel, the display module 200 may include a backlight unit (not shown) disposed below the second polarization layer 272, and may include an LCD panel. It may further include a display panel control IC, a graphic control IC and other circuitry for the operation of.

The touch sensor 10 for detecting a touch position in the touch input device 1000 according to the embodiment of the present invention may be located outside or inside the display module 200.

When the touch sensor 10 is disposed outside the display module 200 in the touch input device 1000, a touch sensor panel may be disposed on the display module 200, and the touch sensor 10 may be a touch sensor panel. Can be included. The touch surface for the touch input device 1000 may be a surface of the touch sensor panel.

When the touch sensor 10 is disposed inside the display module 200 in the touch input device 1000, the touch sensor 10 may be configured to be positioned outside the display panel 200A. In detail, the touch sensor 10 may be formed on upper surfaces of the first substrate layers 261 and 281. In this case, the touch surface of the touch input device 1000 may be an upper surface or a lower surface of FIGS. 3A and 3B as an outer surface of the display module 200.

When the touch sensor 10 is disposed inside the display module 200 in the touch input device 1000, at least some of the touch sensors 10 may be configured to be positioned in the display panel 200A according to an embodiment, and the touch sensor At least some of the other portions 10 may be configured to be positioned outside the display panel 200A. For example, any one of the driving electrode TX and the receiving electrode RX constituting the touch sensor 10 may be configured to be positioned outside the display panel 200A, and the remaining electrodes are inside the display panel 200A. It may be configured to be located at. Specifically, any one of the driving electrode TX and the receiving electrode RX constituting the touch sensor 10 may be formed on upper surfaces of the first substrate layers 261 and 281, and the remaining electrodes are formed on the first substrate layer ( 261 and 281 may be formed on the bottom surface or the top surface of the second substrate layers 262 and 283.

When the touch sensor 10 is disposed inside the display module 200 in the touch input device 1000, the touch sensor 10 may be configured to be positioned inside the display panel 200A. In detail, the touch sensor 10 may be formed on the bottom surface of the first substrate layers 261 and 281 or the top surface of the second substrate layers 262 and 283.

When the touch sensor 10 is disposed inside the display panel 200A, an electrode for operating the touch sensor may be additionally disposed, but various configurations and / or electrodes positioned inside the display panel 200A may perform touch sensing. It may be used as a touch sensor 10 for. Specifically, when the display panel 200A is an LCD panel, at least one of the electrodes included in the touch sensor 10 may include a data line, a gate line, a TFT, and a common electrode (Vcom: common). at least one of an electrode and a pixel electrode, and when the display panel 200A is an OLED panel, at least one of the electrodes included in the touch sensor 10 is a data line. The gate line may include at least one of a gate line, a first power line ELVDD, and a second power line ELVSS.

In this case, the touch sensor 10 may operate as the driving electrode and the receiving electrode described with reference to FIG. 1A to detect the touch position according to the mutual capacitance between the driving electrode and the receiving electrode. In addition, the touch sensor 10 may operate as the single electrode 30 described in FIG. 1B to detect the touch position according to the self capacitance of each of the single electrodes 30. In this case, when the electrode included in the touch sensor 10 is an electrode used to drive the display panel 200A, the display panel 200A is driven in the first time interval, and the second time is different from the first time interval. The touch position may be detected in the section.

4A, 4B and 4D to 4G are cross-sectional views of a touch input device according to an embodiment of the present invention, and FIG. 4C is an exploded perspective view of the touch input device according to an embodiment of the present invention.

Although the display panel 200A is directly attached and laminated to the cover layer 100 in FIGS. 4A and some drawings below, this is merely for convenience of description and the first polarization layers 271 and 282 are the display panel 200A. The upper display module 200 may be laminated and attached to the cover layer 100. When the LCD panel is the display panel 200A, the second polarizing layer 272 and the backlight unit are omitted.

4A to 4G, a cover layer 100 having a touch sensor formed as a touch input device 1000 according to an exemplary embodiment of the present invention is coated on the display module 200 shown in FIGS. 3A and 3B. The touch input device 1000 according to the embodiment of the present invention may also include a case in which the touch sensor 10 is disposed inside the display module 200 shown in FIGS. 3A and 3B. Can be. More specifically, in FIG. 4A to FIG. 4C, the cover layer 100 on which the touch sensor 10 is formed covers the display module 200 including the display panel 200A, but the touch sensor 10 may be a display module. The touch input device 1000 disposed inside the 200 and covered with the cover layer 100 such as glass may be used as an exemplary embodiment of the present invention.

The touch input device 1000 according to the embodiment of the present invention may be a cell phone, a personal data assistant (PDA), a smartphone, a tablet PC, an MP3 player, a notebook, or the like. It may include an electronic device including the same touch screen.

In the touch input device 1000 according to the embodiment of the present invention, the substrate 300 may be, for example, a circuit board for operating the touch input device 1000 together with the housing 320 which is the outermost mechanism of the touch input device 1000. And / or wrap the mounting space 310 in which the battery may be located. In this case, a circuit board for operating the touch input device 1000 may be mounted with a central processing unit (CPU) or an application processor (AP) as a main board. The circuit board and / or the battery for the operation of the display module 200 and the touch input device 1000 are separated through the substrate 300, and the electrical noise generated from the display module 200 and the noise generated from the circuit board Can be blocked.

In the touch input device 1000, the touch sensor 10 or the cover layer 100 may be formed wider than the display module 200, the substrate 300, and the mounting space 310, and thus the housing 320 may be formed. The housing 320 may be formed to surround the display module 200, the substrate 300, and the circuit board together with the touch sensor 10.

The touch input device 1000 according to an exemplary embodiment of the present invention detects a touch position through the touch sensor 10, and is different from an electrode used to detect a touch position and an electrode used to drive a display. May be disposed and used as a pressure sensing unit to detect touch pressure. In this case, the touch sensor 10 may be located inside or outside the display module 200.

Hereinafter, a configuration for pressure detection will be collectively referred to as a pressure sensing unit. For example, in the embodiment illustrated in FIG. 4A, the pressure sensing unit may include a sensor sheet 440, and in the embodiment illustrated in FIG. 4B, the pressure sensing unit may include pressure sensors 450 and 460.

In the touch input device according to the present invention, as illustrated in FIG. 4A, a sensor sheet 440 including pressure sensors 450 and 460 may be disposed between the display module 200 and the substrate 300, as shown in FIG. 4B. As described above, the pressure sensors 450 and 460 may be formed directly on the lower surface of the display panel 200A.

In addition, the pressure sensing unit includes a spacer layer 420 formed of, for example, an air gap, which will be described in detail with reference to FIGS. 4A to 4G.

In some embodiments, the spacer layer 420 may be embodied as an air gap. The spacer layer may be made of an impact absorbing material according to an embodiment. The spacer layer 420 may be filled with a dielectric material in some embodiments. According to an embodiment, the spacer layer 420 may be formed of a material having a recovery force that contracts upon application of pressure and returns to its original shape upon release of pressure. In some embodiments, the spacer layer 420 may be formed of an elastic foam. In addition, since the spacer layer is disposed under the display module 200, the spacer layer may be a transparent material or an opaque material.

In addition, the reference potential layer may be disposed under the display module 200. In detail, the reference potential layer may be formed on the substrate 300 disposed under the display module 200 or the substrate 300 may serve as the reference potential layer. In addition, the reference potential layer is disposed on the substrate 300 and disposed below the display module 200, and formed on a cover (not shown) that functions to protect the display module 200, or the cover itself is a reference. It can serve as a dislocation layer. As the display panel 200A is bent when the pressure is applied to the touch input device 1000 and the display panel 200A is bent, the distance between the reference potential layer and the pressure sensors 450 and 460 may change. In addition, a spacer layer may be disposed between the reference potential layer and the pressure sensors 450 and 460. In detail, a spacer layer may be disposed between the display module 200 and the substrate 300 on which the reference potential layer is disposed or between the cover on which the display module 200 and the reference potential layer are disposed.

In addition, the reference potential layer may be disposed in the display module 200. In detail, the reference potential layer may be disposed on the top or bottom surface of the first substrate layers 261 and 281 of the display panel 200A or the top or bottom surface of the second substrate layers 262 and 283. As the display panel 200A is bent when the pressure is applied to the touch input device 1000 and the display panel 200A is bent, the distance between the reference potential layer and the pressure sensors 450 and 460 may change. In addition, a spacer layer may be disposed between the reference potential layer and the pressure sensors 450 and 460. In the touch input device 1000 illustrated in FIGS. 3A and 3B, a spacer layer may be disposed on or inside the display panel 200A.

Similarly, in some embodiments, the spacer layer may be implemented with an air gap. The spacer layer may be made of an impact absorbing material according to an embodiment. The spacer layer may be filled with a dielectric material in accordance with an embodiment. According to an embodiment, the spacer layer may be formed of a material having a recovery force that contracts upon application of pressure and returns to its original form upon release of pressure. In some embodiments, the spacer layer may be formed of an elastic foam. In addition, since the spacer layer is disposed on or inside the display panel 200A, the spacer layer may be a transparent material.

 In some embodiments, when the spacer layer is disposed inside the display module 200, the spacer layer may be an air gap included in manufacturing the display panel 200A and / or the backlight unit. When the display panel 200A and / or the backlight unit includes one air gap, the air gap may function as a spacer layer, and when the display panel 200A and / or the backlight unit includes the air gap, the plurality of air gaps may be integrated. As a result, the spacer layer may function.

4C is a perspective view of the touch input device 1000 according to the embodiment shown in FIG. 4A of the present invention. As shown in FIG. 4C, in the first example of the present invention, the sensor sheet 440 may be disposed between the display module 200 and the substrate 300 in the touch input device 1000. In this case, the touch input device 1000 may include a spacer layer disposed between the display module 200 of the touch input device 1000 and the substrate 300 to arrange the sensor sheet 440.

Hereinafter, the sensors 450 and 460 for detecting pressure are referred to as pressure sensors 450 and 460 so as to be clearly distinguished from the electrodes included in the touch sensor 10. In this case, since the pressure sensors 450 and 460 are disposed on the rear surface of the display panel 200A, the pressure sensors 450 and 460 may be made of an opaque material as well as a transparent material. When the display panel 200A is an LCD panel, light must be transmitted from the backlight unit, and thus the pressure sensors 450 and 460 may be made of a transparent material such as ITO.

In this case, in order to maintain the spacer layer 420 on which the pressure sensors 450 and 460 are disposed, a frame 330 having a predetermined height may be formed along the edge of the upper portion of the substrate 300. In this case, the frame 330 may be attached to the cover layer 100 with an adhesive tape (not shown). In FIG. 4C, the frame 330 is formed on all edges of the substrate 300 (eg, four sides of a quadrilateral), but the frame 330 is formed of at least a portion of the edges of the substrate 300 (eg, a quadrilateral). Only on three sides). According to an embodiment, the frame 330 may be integrally formed with the substrate 300 on the upper surface of the substrate 300. In an embodiment of the present invention, the frame 330 may be made of a material having no elasticity. In the exemplary embodiment of the present invention, when pressure is applied to the display panel 200A through the cover layer 100, the display panel 200A may be bent together with the cover layer 100. Even if there is no deformation of the body, the magnitude of the touch pressure can be detected.

4D is a cross-sectional view of a touch input device including a pressure sensor according to an embodiment of the present invention. As shown in FIG. 4D, pressure sensors 450 and 460 according to an embodiment of the present invention may be disposed on the bottom surface of the display panel 200A as the spacer layer 420.

The pressure sensor for detecting pressure may include a first sensor 450 and a second sensor 460. In this case, any one of the first sensor 450 and the second sensor 460 may be a driving sensor, and the other may be a receiving sensor. A driving signal may be applied to the driving sensor and a sensing signal including information on electrical characteristics that change as pressure is applied through the receiving sensor may be obtained. For example, when a voltage is applied, mutual capacitance may be generated between the first sensor 450 and the second sensor 460.

4E is a cross-sectional view when pressure is applied to the touch input device 1000 shown in FIG. 4D. The upper surface of the substrate 300 may have a ground potential for noise shielding. When pressure is applied to the surface of the cover layer 100 through the object 500, the cover layer 100 and the display panel 200A may be bent or pressed. Accordingly, the distance d between the ground potential surface and the pressure sensors 450 and 460 may be reduced to d '. In this case, since the fringe capacitance is absorbed to the upper surface of the substrate 300 as the distance d decreases, the mutual capacitance between the first sensor 450 and the second sensor 460 may decrease. . Therefore, the magnitude of the touch pressure may be calculated by obtaining a reduction amount of mutual capacitance from the detection signal obtained through the reception sensor.

In FIG. 4E, the case in which the upper surface of the substrate 300 is the ground potential, that is, the reference potential layer, has been described. However, the reference potential layer may be disposed in the display module 200. In this case, when pressure is applied to the surface of the cover layer 100 through the object 500, the cover layer 100 and the display panel 200A may be bent or pressed. Accordingly, the distance between the reference potential layer disposed inside the display module 200 and the pressure sensors 450 and 460 is changed, and thus the magnitude of the touch pressure can be calculated by acquiring a change in capacitance from a detection signal acquired through the receiving sensor. Can be.

In the touch input device 1000 according to the embodiment of the present invention, the display panel 200A may be bent or pressed in response to a touch applying a pressure. According to an exemplary embodiment, the position showing the largest deformation when the display panel 200A is bent or pressed may not coincide with the touch position, but the display panel 200A may indicate bending at least at the touch position. For example, when the touch position is close to the edge and the edge of the display panel 200A, the position where the display panel 200A is bent or pressed the most may be different from the touch position, but the display panel 200A may be at least the touch position. It may indicate bending or pressing at.

The first sensor 450 and the second sensor 460 are formed on the same layer, and each of the first sensor 450 and the second sensor 460 shown in FIGS. 4D and 4E is shown in FIG. 14A. As shown, it may be composed of a plurality of sensors having a rhombic shape. Here, the plurality of first sensors 450 are connected to each other in the first axis direction, and the plurality of second sensors 460 are connected to each other in the second axis direction perpendicular to the first axis direction. At least one of the 450 and the second sensor 460 may have a plurality of rhombus-shaped sensors connected through a bridge such that the first sensor 450 and the second sensor 460 are insulated from each other. In this case, the first sensor 450 and the second sensor 460 illustrated in FIG. 6 may be configured as a sensor of the type shown in FIG. 14B.

In the above, it is illustrated that the touch pressure is detected from a change in mutual capacitance between the first sensor 450 and the second sensor 460. However, the pressure sensing unit may be configured to include only one pressure sensor of the first sensor 450 and the second sensor 460, in which case one pressure sensor and a ground layer (substrate 300 or display module ( The magnitude of the touch pressure may be detected by detecting a change in capacitance, that is, a self capacitance, between the reference potential layers disposed therein. In this case, a driving signal may be applied to the one pressure sensor, and a change in magnetic capacitance between the pressure sensor and the ground layer may be detected from the pressure sensor.

For example, in FIG. 4D, the pressure sensor may include only the first sensor 450. In this case, the first sensor 450 and the substrate caused by the change of the distance between the substrate 300 and the first sensor 450 may be configured. The magnitude of the touch pressure can be detected from the capacitance change between 300. Since the distance d decreases as the touch pressure increases, the capacitance between the substrate 300 and the first sensor 450 may increase as the touch pressure increases. At this time, the pressure sensor does not have to have a comb-tooth shape or a trident shape, which is necessary to increase the mutual capacitance variation detection accuracy, and may have a single plate (eg, rectangular plate) shape, as shown in FIG. 14D. The plurality of first sensors 450 may be arranged in a grid shape at regular intervals.

4F illustrates the case where the pressure sensors 450 and 460 are formed in the spacer layer 420 on the upper surface of the substrate 300 and the lower surface of the display module 200. In this case, as shown in FIG. 4A, when the pressure sensing unit includes the sensor sheet, the sensor sheet includes the first sensor sheet 440-1 and the second sensor 460 including the first sensor 450. It may be composed of a second sensor sheet (440-2). In this case, any one of the first sensor 450 and the second sensor 460 may be formed on the substrate 300 and the other may be formed on the lower surface of the display module 200. In FIG. 4G, the first sensor 450 is formed on the substrate 300 and the second sensor 460 is formed on the lower surface of the display module 200.

4G illustrates the case where the pressure sensors 450 and 460 are formed in the spacer layer 420 on the upper surface of the substrate 300 and the lower surface of the display panel 200A. In this case, the first sensor 450 is formed on the lower surface of the display panel 200A, and the second sensor 460 includes a second sensor 460 formed on the first insulating layer 470. The second insulating layer 471 may be disposed on the upper surface of the substrate 300 in the form of a sensor sheet, which is formed on the second sensor 460.

When pressure is applied to the surface of the cover layer 100 through the object 500, the cover layer 100 and the display panel 200A may be bent or pressed. Accordingly, the distance d between the first sensor 450 and the second sensor 460 may be reduced. In this case, as the distance d decreases, the mutual capacitance between the first sensor 450 and the second sensor 460 may increase. Therefore, the magnitude of the touch pressure may be calculated by acquiring an increase amount of mutual capacitance from the detection signal obtained through the reception sensor. In this case, since the first sensor 450 and the second sensor 460 are formed on different layers in FIG. 4G, the first sensor 450 and the second sensor 460 do not have to have a comb shape or a trident shape. One of the first sensor 450 and the second sensor 460 may have a shape of one plate (for example, a square plate), and the other may have a plurality of sensors spaced at regular intervals as shown in FIG. 14D. It may be arranged in a grid shape.

In the above description, the pressure sensors 450 and 460 are directly formed on the lower surface of the display panel 200A as illustrated in FIG. 4B, but the sensor sheets including the pressure sensors 450 and 460 are illustrated as shown in FIG. 4A. All of the embodiments in which the 440 is disposed between the display module 200 and the substrate 300 may be applicable. In detail, the sensor sheet 440 including the pressure sensors 450 and 460 may be attached to the lower surface of the display module 200 or may be attached to the upper surface of the substrate 300.

In this case, the upper surface of the substrate 300 may also have a ground potential for noise shielding. 5 illustrates a cross section of a sensor sheet according to an embodiment of the invention. Referring to FIG. 5A, a cross section of the case in which the sensor sheet 440 including the pressure sensors 450 and 460 is attached to the substrate 300 or the display module 200 is illustrated. In this case, since the pressure sensors 450 and 460 are positioned between the first insulating layer 470 and the second insulating layer 471 in the sensor sheet 440, the pressure sensors 450 and 460 are the substrate 300 or the display module 200. Short circuiting can be prevented. In addition, depending on the type and / or implementation manner of the touch input device 1000, the substrate 300 or the display module 200 to which the pressure sensors 450 and 460 are attached may not exhibit a ground potential or may exhibit a weak ground potential. In this case, the touch input device 1000 according to the embodiment of the present invention may further include a ground electrode (not shown) between the substrate 300 or the display module 200 and the insulating layer 470. . According to an embodiment, another insulating layer (not shown) may be further included between the ground electrode and the substrate 300 or the display module 200. In this case, the ground electrode may prevent the size of the capacitance generated between the first sensor 450 and the second sensor 460, which are pressure sensors, from becoming too large.

The first sensor 450 and the second sensor 460 may be implemented in different layers according to the exemplary embodiment to configure the sensor layer. FIG. 5B illustrates a cross section when the first sensor 450 and the second sensor 460 are implemented on different layers. As illustrated in FIG. 5B, the first sensor 450 is formed on the first insulation layer 470, and the second sensor 460 is second insulation disposed on the first sensor 450. May be formed on layer 471. In some embodiments, the second sensor 460 may be covered with a third insulating layer 472. That is, the sensor sheet 440 may include a first insulating layer 470 to a third insulating layer 472, a first sensor 450 and a second sensor 460. In this case, since the first sensor 450 and the second sensor 460 are located on different layers, they may be implemented to overlap each other. For example, as illustrated in FIG. 14C, the first sensor 450 and the second sensor 460 may be formed similar to the pattern of the driving electrode TX and the receiving electrode RX arranged in the structure of MXN. . At this time, M and N may be one or more natural numbers. Alternatively, as shown in FIG. 14A, a rhombic first sensor 450 and a second sensor 460 may be located on different layers.

FIG. 5C illustrates a cross section when the sensor sheet 440 includes only the first sensor 450. As illustrated in FIG. 5C, the sensor sheet 440 including the first sensor 450 may be disposed on the substrate 300 or the display module 200.

FIG. 5D illustrates a second sensor sheet 440-which is attached to the first sensor sheet 440-1 including the first sensor 450 on the substrate 300 and includes a second sensor 460. An example in which 2) is attached to the display module 200 is illustrated. As illustrated in FIG. 5D, the first sensor sheet 440-1 including the first sensor 450 may be disposed on the substrate 300. In addition, the second sensor sheet 440-2 including the second sensor 460 may be disposed on the bottom surface of the display module 200.

As described with respect to FIG. 5A, when the substrate 300 or the display module 200 to which the pressure sensors 450 and 460 are attached does not exhibit a ground potential or exhibits a weak ground potential, FIG. In (d) to (d), the sensor sheet 440 may further include a ground electrode (not shown) between the substrate 300 or the display module 200 and the first insulating layers 470, 470-1, and 470-2. Can be. In this case, the sensor sheet 440 may further include an additional insulating layer (not shown) between the ground electrode (not shown) and the substrate 300 or the display module 200.

In the touch input device 1000 according to the present invention, the pressure sensors 450 and 460 may be directly formed on the display panel 200A. 6A to 6C are cross-sectional views illustrating an embodiment of a pressure sensor directly formed on various display panels in a touch input device according to an embodiment of the present invention.

First, FIG. 6A shows pressure sensors 450 and 460 formed in display panel 200A using an LCD panel. Specifically, as shown in FIG. 6A, pressure sensors 450 and 460 may be formed on the bottom surface of the second substrate layer 262. In this case, the pressure sensors 450 and 460 may be formed on the lower surface of the second polarization layer 272. When pressure is applied to the touch input device 1000, when detecting the touch pressure based on the mutual capacitance change amount, a driving signal is applied to the driving sensor 450, and the reference potential layer spaced apart from the pressure sensors 450 and 460. Receives an electrical signal from the receiving sensor 460 including information on the capacitance that changes in accordance with the distance change with the over-pressure sensor (450,460). In the case of detecting the touch pressure based on the amount of change in the self capacitance, a driving signal is applied to the pressure sensors 450 and 460, and changes according to a change in the distance between the reference potential layer spaced apart from the pressure sensors 450 and 460 and the pressure sensors 450 and 460. An electrical signal including information on the capacitance is received from the pressure sensors 450 and 460. Here, the reference potential layer may be a substrate 300 or a cover disposed between the display panel 200A and the substrate 300 and performing a function of protecting the display panel 200A.

Next, FIG. 6B shows pressure sensors 450 and 460 formed on the bottom surface of display panel 200A using an OLED panel (especially an AM-OLED panel). In detail, the pressure sensors 450 and 460 may be formed on the bottom surface of the second substrate layer 283. At this time, the method for detecting the pressure is the same as the method described with reference to Figure 6a.

In the case of the OLED panel, since light is emitted from the organic layer 280, the pressure sensors 450 and 460 formed on the bottom surface of the second substrate layer 283 disposed under the organic layer 280 may be made of an opaque material. However, in this case, since the pattern of the pressure sensors 450 and 460 formed on the bottom surface of the display panel 200A may be visible to the user, the second substrate may be directly formed on the bottom surface of the second substrate layer 283. After applying a light blocking layer such as black ink on the lower surface of the layer 283, pressure sensors 450 and 460 may be formed on the light blocking layer.

6B, pressure sensors 450 and 460 are formed on the bottom surface of the second substrate layer 283, but a third substrate layer (not shown) is disposed below the second substrate layer 283. Pressure sensors 450 and 460 may be formed on the lower surface of the three substrate layer. In particular, when the display panel 200A is a flexible OLED panel, since the display panel 200A composed of the first substrate layer 281, the organic material layer 280, and the second substrate layer 283 is very thin and well bent, A third substrate layer that is relatively hard to be bent may be disposed below the substrate layer 283.

Next, FIG. 6C shows pressure sensors 450 and 460 formed in display panel 200A using an OLED panel. In detail, pressure sensors 450 and 460 may be formed on an upper surface of the second substrate layer 283. At this time, the method for detecting the pressure is the same as the method described with reference to Figure 6a.

6C, the display panel 200A using the OLED panel has been described as an example, but pressure sensors 450 and 460 are formed on the upper surface of the second substrate layer 272 of the display panel 200A using the LCD panel. It is possible.

6A to 6C, the pressure sensors 450 and 460 are formed on the top or bottom surfaces of the second substrate layers 272 and 283, but the pressure sensors 450 and 460 are on the top and bottom surfaces of the first substrate layers 261 and 281. It is also possible to be formed in.

6A to 6C, the pressure sensing unit including the pressure sensors 450 and 460 is formed directly on the display panel 200A. However, the pressure sensing unit is directly formed on the substrate 300 and the potential layer is formed on the display panel. It may be 200A or a cover disposed between the display panel 200A and the substrate 300 to perform a function of protecting the display panel 200A.

6A to 6C, the reference potential layer is disposed below the pressure sensing unit. However, the reference potential layer may be disposed inside the display panel 200A. In detail, the reference potential layer may be disposed on the top or bottom surface of the first substrate layers 261 and 281 of the display panel 200A, or the top or bottom surface of the second substrate layers 262 and 283.

In the touch input device 1000 according to the present invention, the pressure sensors 450 and 460 for detecting the capacitance change amount are formed of the first sensor 450 and the sensor sheet formed directly on the display panel 200A. It may be composed of a second sensor 460 configured in the form. Specifically, the first sensor 450 is formed directly on the display panel 200A as described with reference to FIGS. 6A to 6C, and the second sensor 460 is configured in the form of a sensor sheet as described with reference to FIG. 4G and is touched. It may be attached to the input device 1000.

In the touch input device 1000 according to the exemplary embodiment of the present invention, when the pressure sensor controller 1300 and the touch sensor controller 1100 are integrated and driven as one IC, the controller of the integrated IC may be connected to the touch sensor 10. The scanning of the pressure sensing unit may be performed simultaneously with the scanning, or the controller of the integrated IC may be time-divided to perform scanning of the touch sensor 10 in the first time interval, and a second time interval different from the first time interval. The control signal may be generated to perform scanning of the pressure sensing unit.

In the above description, the pressure sensor 450 included in the pressure sensing unit is configured as an electrode, and as the electrical characteristics detected by the pressure sensing unit, the amount of pressure is detected by detecting an amount of change in capacitance caused by bending of the display panel 200A. Although described, the present invention is not limited thereto, and the pressure sensor 450 included in the pressure sensing unit includes a strain gauge, and the pressure sensor changing as the display panel 200A is bent as an electrical characteristic detected by the pressure sensing unit ( The magnitude of the pressure may be detected by detecting the amount of change in the resistance value 450.

Up to now, the physical configuration of the touch input device 1000 when touch pressure is applied to the touch input device 1000 has been described. Hereinafter, a method of removing noise generated when a touch pressure is applied to the touch input device 1000 will be described.

When touch pressure is applied to the touch input device 1000, noise may be generated from the pressure sensors 450 and 460. Noise generated from the pressure sensors 450 and 460 may include common mode noise and random noise. In the case of the present invention, it is intended to remove common mode noise according to the following examples. In addition, according to the following embodiment, random noise may also be partially changed / reduced.

FIG. 8 is a detailed block diagram of the control unit 13 of the touch input device according to the embodiment of the present invention, and FIG. 9 is a flowchart illustrating a common mode noise removing method of the touch input device according to the embodiment of the present invention.

As shown in FIG. 8 and FIG. 9, the positioning unit 13a determines a touch position at which touch pressure is applied to the touch input device 1000 (S100).

The object applying the touch pressure may include a finger, a stylus, or the like. The touch position may be determined by two-dimensional coordinates (x, y) on the touch surface of the touch input device 1000.

The signal measurement value acquisition unit 13b obtains a current signal measurement value from the plurality of pressure sensors 450 and 460 driven at the touch pressure at the touch position (S200) and a reference corresponding to the touch position from the plurality of pressure sensors 450 and 460. The signal measurement value may be obtained (S300). In the present invention, the current signal measurement value may be an actual capacitance change measurement value / resistance value obtained by the touch pressures by the pressure sensors 450 and 460, and the reference signal measurement value is a standard capacitance change measurement value / acquired by the unit touch pressure. It may be a resistance value. The reference signal measurement may be measured before applying the touch pressure and stored in advance in a memory (not shown).

The noise removing unit 13c may remove common mode noise generated from the plurality of pressure sensors 440 by using the average value of the current signal measurement value and the average value of the reference signal measurement value (S400).

The relationship between the magnitude of the touch pressure, the current signal measurement value, and the reference signal measurement value in steps S200 and S300 may be expressed by the following equation.

For reference, the following equation is for calculating the magnitude of the touch pressure f currently applied using the reference signal measurement value and the current signal measurement value.

[Equation 1]

Here, g _i denotes a reference signal measurement value, f denotes a magnitude of touch pressure currently applied, s _i denotes a current signal measurement value, and N denotes the number of pressure sensors 450 and 460, respectively. Specifically, g _i may be a signal value measured by the i-th pressure sensor when a unit touch pressure is applied.

The reference signal measurement value is a signal value measured by a plurality of pressure sensors when unit force is applied to a position where a touch is made, and is calculated from a value previously stored and stored in a memory (not shown) or stored value. It may be a value. The signal measurement value acquisition unit 13b is a value corresponding to a position where a current touch is made among signal values previously stored in a memory (not shown) corresponding to each of the plurality of pressure sensors (i: 1 to N) with respect to the plurality of touch positions. Can be obtained as a reference signal measurement value.

On the other hand, when the reference signal measurement value is not stored in the memory for the touched position, the signal measurement value acquisition unit 13b interpolates the stored reference signal measurement values for the plurality of positions closest to the touched position. By performing interpolation, a reference signal measurement value for the touched position may be obtained.

Therefore, according to the exemplary embodiment of the present invention, the reference signal measurement value can be obtained even when a touch pressure is applied to any part of the touch panel, so that the currently applied touch pressure f can always be calculated.

When the touch pressure f is applied to the touch input device 1000 including the N pressure sensors 450 and 460, the average value and the reference signal measurement values for the current signal measurements measured from each of the N pressure sensors 450 and 460, respectively. An average value for may be obtained.

The relationship between the average value of the current signal measurement value and the average value of the reference signal measurement value in step S400 can be expressed as the following equation.

[Equation 2]

here,

Is the average of the reference signal measurements,

Represents the average value of the current signal measurement.

Specific steps of S400 using Equation 2 are as follows.

That is, the noise removing unit 13c may remove the common mode noise by using a value obtained by subtracting the average value of the current signal measurement value from the current signal measurement value and a value obtained by subtracting the average value of the reference signal measurement value from the reference signal measurement value, respectively. Can be.

This feature can be confirmed through Equations 3 and 4 below.

[Equation 3]

[Equation 4]

The noise removing unit 13c may remove the common mode noise by substituting the reference signal measurement value with the noise inclusion information and subtracting the average value of the noise inclusion information from the noise inclusion information. Here, the noise inclusion information means a value obtained by adding the common mode noise and the random noise to the reference signal measurement value. Then, the common mode noise is removed and the random noise is changed to a value different from the initial random noise value.

This feature can be seen through Equations 5 and 6 below.

[Equation 5]

In this case, g ' _i means noise inclusion information, g _i means a reference signal measurement value, Common Mode Noise (CMN), and RNi (Random Noise of the i-th pressure sensor).

[Equation 6]

Looking at Equation 6, the CMN was finally removed, RNk is

You can see that the value has changed to RN'k, which has been removed.

Features, structures, effects, etc. described in the above embodiments are included in one embodiment of the present invention, and are not necessarily limited to one embodiment. Furthermore, the features, structures, effects, and the like illustrated in the embodiments may be combined or modified with respect to other embodiments by those skilled in the art to which the embodiments belong. Therefore, contents related to such combinations and modifications should be construed as being included in the scope of the present invention.

In addition, the above description has been made with reference to the embodiment, which is merely an example and is not intended to limit the present invention. It will be appreciated that various modifications and applications are possible. For example, each component specifically shown in the embodiment can be modified. And differences relating to such modifications and applications will have to be construed as being included in the scope of the invention defined in the appended claims.

According to an embodiment of the present invention, the common mode noise generated when the pressure is applied to the touch input device can be removed.

According to an embodiment of the present invention, random noise generated when pressing the touch input device can be reduced.

Claims (14)

1. In the common mode noise removal method of the touch input device for detecting the touch pressure by using a plurality of pressure sensors,

   Determining a touch position at which the touch pressure is applied to the touch input device;

   Acquiring a current signal measurement from the plurality of pressure sensors driven by the touch pressure at the touch position;

   Obtaining a reference signal measurement value corresponding to the touch position from the plurality of pressure sensors; And

   And removing the common mode noise generated from the plurality of pressure sensors using the average value of the current signal measurement value and the average value of the reference signal measurement value.

   How to remove common mode noise of touch input device.
2. The method of claim 1,

   The common mode noise is removed by using a value obtained by subtracting the average value of the current signal measurement value from the current signal measurement value and a value obtained by subtracting the average value of the reference signal measurement value from the reference signal measurement value, respectively. ,

   How to remove common mode noise of touch input device.
3. The method of claim 1,

   The reference signal measurement value is replaced with noise inclusion information obtained by adding the common mode noise and random noise to the reference signal measurement value.

   Removing the common mode noise and changing the random noise by subtracting the average value of the noise inclusion information from the noise inclusion information;

   How to remove common mode noise of touch input device.
4. The method of claim 1,

   The current signal measurement value and the reference signal measurement value include an amount of capacitance change obtained by applying the touch pressure to the touch input device from the plurality of pressure sensors.

    How to remove common mode noise of touch input device.
5. The method of claim 1,

   The current signal measurement value and the reference signal measurement value may include resistance values obtained from the plurality of pressure sensors by applying the touch pressure to the touch input device.

    How to remove common mode noise of touch input device.
6. The method of claim 1,

   The reference signal measurement value is a signal value measured from the plurality of pressure sensors when a unit touch pressure is applied to the touch position,

   Acquiring the reference signal measurement value by reading a pre-stored signal value corresponding to each of the plurality of pressure sensors;

   How to remove common mode noise of touch input device.
7. The method of claim 1,

   When the touch position is a position where the reference signal measurement value cannot be obtained by reading a pre-stored signal value, interpolation with the stored reference signal measurement value is performed for a plurality of positions close to the corresponding position. Performing reference signal measurement acquisition,

   How to remove common mode noise of touch input device.
8. A plurality of pressure sensors for detecting touch pressure applied to the touch input device;

   A touch sensor for detecting a touch position to which the touch pressure is applied; And

   And a controller controlling the plurality of pressure sensors and the touch sensor to remove common mode noise generated from the plurality of pressure sensors.

   The control unit,

   A positioning unit determining the touch position to which the touch pressure is applied;

   A signal measurement value acquisition unit for obtaining a current signal measurement value from the plurality of pressure sensors driven by the touch pressure at the touch position, and obtaining a reference signal measurement value corresponding to the touch position from the plurality of pressure sensors; And

   And a noise removing unit configured to remove the common mode noise generated from the plurality of pressure sensors using the average value of the current signal measurement value and the average value of the reference signal measurement value.

   Touch input device.
9. The method of claim 8,

   The noise removing unit,

   Removing the common mode noise by using a value obtained by subtracting an average value of the current signal measurement value from the current signal measurement value and a value obtained by subtracting an average value of the reference signal measurement value from the reference signal measurement value, respectively;

   Touch input device.
10. The method of claim 8,

    The noise removing unit,

    The reference signal measurement value is replaced with noise inclusion information obtained by adding the common mode noise and random noise to the reference signal measurement value.

    Removing the common mode noise and changing the random noise by subtracting the average value of the noise inclusion information from the noise inclusion information;

    Touch input device.
11. The method of claim 8,

    The current signal measurement value and the reference signal measurement value include an amount of change in capacitance obtained from the plurality of pressure sensors by applying the touch pressure to the touch input device.

    Touch input device.
12. The method of claim 8,

    The current signal measurement value and the reference signal measurement value may include resistance values obtained from the plurality of pressure sensors by applying the touch pressure to the touch input device.

    Touch input device.
13. The method of claim 8,

    The reference signal measurement value is a signal value measured by the plurality of pressure sensors when a unit touch pressure is applied to the touch position,

    The signal measurement value acquisition unit,

    Acquiring the reference signal measurement value by reading a pre-stored signal value corresponding to each of the plurality of pressure sensors;

    Touch input device.
14. The method of claim 8,

    The signal measurement value acquisition unit,

    When the touch position is a position where the reference signal measurement value cannot be obtained by reading a pre-stored signal value, interpolation with the stored reference signal measurement value is performed for a plurality of positions close to the corresponding position. Performing reference signal measurement acquisition,

    Touch input device.

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