KR20130067076A - Data processing method and apparatus for touch screen - Google Patents

Abstract

PURPOSE: A data processing method of a touch screen and a device thereof are provided to increase sensitivity of touch determination without increasing the number of sensing and decreasing a touch report rate. CONSTITUTION: A touch screen includes Tx lines, Rx lines, and a touch recognition area including the sensor nodes. A touch screen driving circuit(12) receives voltage of the sensor nodes through the Rx lines by applying a driving pulse to the Tx lines and synchronizing the driving pulse. The touch screen driving circuit generates data with touch by sampling the voltage and converting the voltage into digital data. A touch recognition algorithm execution unit(30) maps a predetermined edge detection mask in the data and estimates a coordinate for the touch input based on an edge detection calculation result.

Description

DATA PROCESSING METHOD AND APPARATUS FOR TOUCH SCREEN}

The present invention relates to a data processing method and apparatus of a touch screen.

A user interface (UI) enables communication between a person (user) and various electric or electronic devices, allowing a user to easily control the device as desired. Representative examples of such a user interface include a keypad, a keyboard, a mouse, an on screen display (OSD), a remote controller having infrared communication or radio frequency (RF) communication function, and the like. User interface technology has been developed to enhance the user's sensibility and ease of operation. Recently, the user interface has evolved into a touch UI, a voice recognition UI, a 3D UI, and the like.

Touch UI is being adopted to portable information devices, and it is being applied to home appliances. As an example of a touch screen for implementing a touch UI, a mutual capacitance type touch screen capable of sensing not only touch but also proximity and recognizing multi-touch (or proximity) has been in the spotlight.

The mutual capacitive touch screen includes Tx lines, Rx lines intersecting the Tx lines, and sensor nodes formed at the intersection of the Tx lines and the Rx lines. Each of the sensor nodes has a mutual capacity. The touch screen driving device senses a change in the voltage charged in the sensor nodes before and after the touch (or proximity) to judge whether or not the conductive material is in contact (or proximity) and its position.

The conventional touch screen scanning method sequentially applies driving pulses to the Tx lines and performs sampling and analog-to-digital conversion of the sensor node voltage to each of the sensor nodes in the Rx driving circuit. Therefore, The sensing time is long. In order to increase the sensitivity of the touch screen, the sensor node voltage must be repeatedly accumulated in the sampling capacitor to increase the amount of change before and after the touch. In this case, since the number of sensing of each of the sensor nodes needs to be increased, the number of sensing and the total sensing time are increased, thereby reducing the touch report rate. The touch report rate refers to the number of touch coordinate values transmitted per second.

The present invention provides a data processing method and apparatus for a touch screen that can increase the sensitivity of the touch presence determination without increasing the number of sensing.

According to an embodiment of the present invention, a data processing method of a touch screen includes: an edge detection calculation step of mapping a predetermined edge detection mask to touch furnace data to multiply coefficients of the edge detection mask by the touch furnace data and add the results; And estimating coordinates for each touch input generated on the touch screen based on the result of the edge detection operation.

The edge detection mask may include a first coefficient set at the center of the edge detection mask; And a second coefficient set around the center of the edge detection mask. The first coefficient is a positive value, and the second coefficient is a negative value.

The center data located in the center among the touch row data obtained from the sensor nodes existing in the same size as the edge detection mask is multiplied by the first coefficient. Peripheral data other than the center data among the touch raw data obtained from the sensor nodes present in the same size as the edge detection mask are multiplied by the second coefficient 1: 1. The sum of the center data multiplied by the first coefficient and the peripheral data multiplied by the second coefficient is calculated as the edge detection calculation result data for the center data.

According to another aspect of the present invention, there is provided a data processing method of a touch screen, the method comprising: generating sensor data of a first touch by sensing sensor nodes of blocks divided in a touch recognizable area of the touch screen in units of blocks; Generating a second touch furnace data by precisely sensing sensor nodes within the block in which the touch input is detected when it is determined that a touch input is detected based on the analysis result of the first touch furnace data; An edge detection calculation step of mapping a predetermined edge detection mask to the first touch furnace data to multiply the coefficients of the edge detection mask by the first touch furnace data and add the results; And determining whether there is a touch input generated on the touch screen based on a result of the edge detection operation.

The data processing method of the touch screen further includes estimating coordinates for each of the second touch input data after the edge detection operation after performing the edge detection operation on the second touch furnace data.

A touch screen data processing apparatus according to an embodiment of the present invention includes touch recognition including Tx lines, Rx lines crossing the Tx lines, and sensor nodes formed at an intersection of the Tx lines and the Rx lines. A touch screen including a possible area; A touch screen driving circuit which applies a driving pulse to the Tx lines, receives the voltages of the sensor nodes through the Rx lines in synchronization with the driving pulses, samples the received voltage, and converts the received voltage into digital data to generate touch-through data. in; And a coordinate for each touch input generated on the touch screen based on an edge detection operation result of mapping a preset edge detection mask to the touch furnace data, multiplying the coefficients of the edge detection mask by the touch furnace data, and adding the results. And a touch recognition algorithm execution unit for estimating.

A data processing apparatus of a touch screen according to another embodiment of the present invention includes a touch including Tx lines, Rx lines crossing the Tx lines, and sensor nodes formed at an intersection of the Tx lines and the Rx lines. A touch screen including a recognizable area, the touch recognizable area being divided into two or more blocks; A touch screen driving circuit which applies a driving pulse to the Tx lines, receives the voltages of the sensor nodes through the Rx lines in synchronization with the driving pulses, samples the received voltage, and converts the received voltage into digital data to generate touch-through data. in; And a coordinate for each touch input generated on the touch screen based on an edge detection operation result of mapping a preset edge detection mask to the touch furnace data, multiplying the coefficients of the edge detection mask by the touch furnace data, and adding the results. And a touch recognition algorithm execution unit for estimating.

The touch screen driving circuit senses sensor nodes of blocks divided in a touch recognition region of the touch screen in units of blocks to output data using a first touch, and based on a result of analyzing the first touch furnace data. When it is determined that the input is detected, only the block in which the touch input is detected is precisely sensed by the sensor nodes in the block and outputs data to the second touch.

The touch recognition algorithm execution unit performs an edge detection operation on the first touch furnace data to determine the presence or absence of a touch input.

The present invention amplifies touch input data by calculating the touch coefficient data and the coefficients of the preset edge detection mask while reducing other data, and then determining whether there is a touch (or proximity) input based on the operation result. As a result, the present invention can increase the sensitivity of the touch presence determination without increasing the number of sensing and without reducing the touch report rate.

Furthermore, the present invention virtually divides the touch screen into two or more blocks, and quickly determines whether there is a touch (or proximity) input in units of blocks, and then precisely senses the touch (or proximity) input position. As a result, the present invention can further reduce the number of sensing and the total sensing time of the touch screen.

The present invention can reduce the noise influencing time that may affect the touch screen by reducing the total sensing time of the touch screen and verify the O-touch that is misidentified as touch in the block sensing through partial sensing to minimize the influence of noise and to recognize the touch. Can increase the precision.

1 is a block diagram illustrating a touch screen and a display device according to an exemplary embodiment of the present invention.
FIG. 2 is a diagram illustrating a touch screen driving device in FIG. 1.
3 is a block diagram showing the touch screen driving circuit in detail.
4 through 6 illustrate various embodiments of a touch screen and a display panel.
7 is a diagram schematically illustrating an example of mapping a touch screen and an edge detection mask.
8 shows coefficients of an edge detection mask.
FIG. 9 is a diagram illustrating dummy data configured for an edge detection operation for sensor nodes existing at edges and corners of a touch screen.
10 is a diagram illustrating an example of an edge detection operation.
FIG. 11 is a diagram illustrating an example in which each of the calculation results is designated as a variable in order to explain the calculation result of FIG. 10.
12 is a graph showing touch raw data before an edge detection operation in the example of FIG. 10.
FIG. 13 is a graph illustrating touch row data after an edge detection operation in the example of FIG. 10.
14 is a flowchart illustrating a touch screen driving method according to an embodiment of the present invention.
15 and 16 illustrate block sensing periods and partial sensing periods.
17A to 17C are graphs illustrating an example of touch row data before and after an edge detection operation and touch row data generated as a result of partial sensing.
18 is a diagram illustrating an example in which a touch input is generated within one block.
FIG. 19 is a waveform diagram illustrating driving pulses applied to a touch screen in the example of FIG. 18.
20 is a diagram illustrating an example in which a touch input is generated at a boundary between neighboring blocks.
FIG. 21 is a waveform diagram illustrating driving pulses applied to a touch screen in the example of FIG. 20.
22 is a diagram illustrating an example of generating a multi-touch input.
FIG. 23 is a waveform diagram illustrating driving pulses applied to a touch screen in the example of FIG. 22.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Like reference numerals throughout the specification denote substantially identical components. In the following description, when it is determined that a detailed description of known functions or configurations related to the present invention may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

1 to 3, a touch screen and a display device according to an exemplary embodiment of the present invention include a display panel DIS, a display driving circuit, a touch screen TSP, a touch screen driving circuit, and the like.

The display device of the present invention is a liquid crystal display (LCD), a field emission display (FED), a plasma display panel (PDP), an organic light emitting diode display (Organic Light Emitting Display) , OLED), and electrophoretic display devices (Electrophoresis, EPD) can be implemented based on a flat panel display device. In the following embodiments, a display device is described as a liquid crystal display device as an example of a flat panel display device, but it should be noted that the display device of the present invention is not limited to a liquid crystal display device.

The display panel DIS includes a liquid crystal layer formed between two substrates. The lower substrate of the display panel DIS includes a plurality of data lines D1 to Dm and m are natural numbers, a plurality of gate lines G1 to Gn and n are natural numbers intersecting the data lines D1 to Dm. A plurality of TFTs formed at intersections of the data lines D1 to Dm and the gate lines G1 to Gn, a plurality of pixel electrodes for charging data voltages to liquid crystal cells, and a pixel electrode And a storage capacitor to maintain the voltage of the liquid crystal cell.

The pixels of the display panel DIS are formed in a pixel region defined by the data lines D1 to Dm and the gate lines G1 to Gn and arranged in a matrix form. Each liquid crystal cell of the pixels is driven by an electric field applied according to a voltage difference between a data voltage applied to the pixel electrode and a common voltage applied to the common electrode to control the amount of incident light. The TFTs are turned on in response to gate pulses from the gate lines G1 to Gn to supply a voltage from the data lines D1 to Dm to the pixel electrodes of the liquid crystal cell.

The upper substrate of the display panel DIS may include a black matrix, a color filter, and the like. The lower substrate of the display panel DIS may be implemented with a COT (Color Filter On TFT) structure. In this case, the black matrix and the color filter can be formed on the lower substrate of the display panel DIS.

A polarizing plate is attached to each of the upper and lower substrates of the display panel DIS, and an alignment layer for setting the pretilt angle of the liquid crystal is formed on an inner surface of the display panel DIS. A column spacer for maintaining a cell gap of the liquid crystal cell is formed between the upper substrate and the lower substrate of the display panel DIS.

The backlight unit may be disposed under the rear surface of the display panel DIS. The backlight unit is implemented as an edge type or direct type backlight unit to emit light to the display panel DIS. The display panel DIS may be implemented in any known liquid crystal mode such as TN (Twisted Nematic) mode, VA (Vertical Alignment) mode, IPS (In Plane Switching) mode and FFS (Fringe Field Switching) mode.

The display driving circuit includes a data driving circuit 12, a scan driving circuit 14, and a display timing controller 20, and writes the video data voltage of the input image to the pixels of the display panel DIS. The data driving circuit 12 converts the digital video data RGB input from the display timing controller 20 into an analog positive / negative gamma compensation voltage to output a data voltage. The data voltage output from the data driving circuit 12 is supplied to the data lines D1 to Dm. The scan driving circuit 14 sequentially supplies a gate pulse (or a scan pulse) synchronized with the data voltage to the gate lines G1 to Gn to select a line of the display panel DIS to which the data voltage is written.

The display timing controller 20 receives digital video data RGB of an input image from an external host system and transmits the data to the data driving circuit 12. In addition, the display timing controller 20 scan timing control signal for controlling the operation timing of the data driving circuit 12 and the scan driving circuit 14 based on the timing signal input from the host system together with the input image data. And a data timing control signal. The timing signal input from the host system includes a vertical synchronization signal (Vsync), a horizontal synchronization signal (Hsync), a data enable signal (Data Enable, DE), a main clock (MCLK), and the like. ) And the horizontal synchronization signal Hsync may be omitted. The scan timing control signal includes a gate start pulse (GSP), a gate shift clock, a gate output enable signal (GOE), and the like. The data timing control signal includes a source sampling clock (SSC), a polarity control signal (Polarity), a source output enable signal (SOE), and the like.

The touch screen TSP may be bonded to the upper polarizer POL1 of the display panel DIS as shown in FIG. 4, or may be formed between the upper polarizer POL1 and the upper substrate GLS1 as shown in FIG. 5. In addition, the sensor nodes of the touch screen TSP may be formed on the lower substrate in an in-cell type together with the pixel array in the display panel DIS as shown in FIG. 4 to 6, "PIX" means a pixel electrode of a liquid crystal cell, "GLS2" means a lower substrate, and "POL2" means a lower polarizing plate, respectively.

The touch screen TSP includes Tx lines (T1 to Tj, j is a positive integer less than n), Rx lines (R1 to Ri, i being an amount less than m) crossing the Tx lines Integer), and ixj sensor nodes TSN formed at intersections of Tx lines T1 to Tj and Rx lines R1 to Ri. The touch screen is divided into virtual blocks and each of the blocks includes two or more Tx lines and two or more Rx lines.

The touch screen driving circuit supplies driving pulses to the Tx lines T1 to Tj and senses sensor node voltages through the Rx lines R1 to Ri in synchronization with the driving pulses. The touch screen driving circuit includes a Tx driving circuit 32, an Rx driving circuit 34, and a touch Rx and Tx timing controller (hereinafter, referred to as a “timing controller”) 36. The Tx driving circuit 32, the Rx driving circuit 34, and the timing controller 36 may be integrated in one ROIC (Read-out IC) 40 as shown in FIG. 3.

The Tx driving circuit 32 selects a Tx channel to output a driving pulse in response to the Tx setup signal SUTx input from the timing controller 36 and drives the Tx lines T1 to Tj connected to the selected Tx channel. Apply a pulse. By repeatedly accumulating and charging the voltage of the sensor node TSN to the sampling capacitor of the Rx driving circuit 34 N times (N is a natural number of 2 or more), the sensing sensitivity can be improved by increasing the amount of change of the sensor node voltage before and after the touch. To this end, driving pulses applied to each of the Tx lines T1 to Tj may include N driving pulses (N is a positive integer of 2 or more) that are continuously generated at predetermined time intervals. If j sensor nodes are connected to one Tx line, drive pulses including N pulses may be supplied to the Tx line successively j times, and then drive pulses may be supplied to the next Tx line in the same manner. As another embodiment, if j sensor nodes TSN are connected to one Tx line, (j / SUN +1) driving pulses may be continuously supplied to the Tx line. Here, SUN (Sensing Unit Number) means the number of sensor nodes simultaneously received through N Rx lines. SUN is set by the Rx setup signal SURx and the Rx drive circuit 34 simultaneously sets up the N Rx channels in response to the Rx setup signal SURx, And simultaneously receives the voltages of the nodes. 1 " (j / SUN +1) " means that the drive pulse is supplied to the Tx lines one more time to receive the sensor nodes over the remaining Rx channels when the remainder of j / SUN is not zero.

The Rx lines R1 to Ri are connected to input terminals of the Rx driving circuit 34 through the differential amplifier 50 as shown in FIG. 3. The differential amplifier 50 differentially amplifies the voltages of the sensor nodes input through the neighboring Rx lines R1 to Ri to the Rx driving circuit 34. The Rx driving circuit 34 selects an Rx channel to receive the sensor node voltage in response to the Rx setup signal SURx input from the timing controller 36, and selects Rx lines R1 to Ri connected to the selected Rx channel. Receive the voltage across the sensor nodes. The Rx driving circuit 34 samples the voltage of the sensor node received through the Rx lines R1 to Ri and converts the voltage into digital data. The digital data output from the Rx driving circuit 34 is touch raw data (Tdata) and includes change amount information before and after touch at each of the sensor nodes. The greater the amount of change before and after the touch, the higher the digital value of the touch raw data. On the other hand, the touch raw data with no touch (or proximity) input or noise effect is small because there is little change before and after touch. The touch raw data Tdata is transmitted to the touch recognition algorithm execution unit 30.

The timing controller 36 is configured to set up a setup signal SUTx for setting a Tx channel for outputting a driving pulse from the Tx driving circuit 32 and an Rx channel for receiving a sensor node voltage in the Rx driving circuit 34. Generates a setup signal SURx. In addition, the timing controller 36 generates timing control signals for controlling the operation timing of the Tx driving circuit 32 and the Rx driving circuit 34.

The touch recognition algorithm execution unit 30 inputs touch raw data Tdata input from the Rx driving circuit 34 to the built-in edge detection filter. The edge detection filter maps a touch edge data Tdata with a preset edge detection mask EM and adds the results of multiplying the coefficients of the edge detection mask EM by the touch row data Tdata. . The edge detection filter amplifies the amount of change in the touch row data to improve the signal to noise ratio (SNR) of the touch row data Tdata. The touch row data Tdata obtained from the sensor node at the touch (or proximity) input position is edge-detected compared to the touch row data Tdata obtained from the sensor node having no touch (or proximity) input or the change amount of change before and after touch is small due to noise. Amplified by the filter at a larger amplification rate.

In the edge detection calculation method, among the touch row data Tdata obtained from the sensor nodes existing within the same size as the edge detection mask EM, the center data located in the center is a first set in the center of the edge detection mask EM. It is multiplied by the coefficient α. Peripheral data other than the center data among the touch raw data Tdata obtained from the sensor nodes existing in the same size as the edge detection mask EM may have a second coefficient β set around the edge detection mask EM. Multiply by 1: 1. The sum of the central data multiplied by the first coefficient α and the peripheral data multiplied by the second coefficient β is calculated as the edge detection calculation result data for the central data.

When the coefficients of the edge detection mask and the touch row data Tdata are calculated, the touch (or proximity) input data of the touch row data Tdata is amplified largely, while the data including noise is lowered. Accordingly, the present invention facilitates the determination of the presence of touch (or proximity) input by increasing the signal-to-noise ratio (SNR) by increasing the difference between the touch (or proximity) input data and the data not using the edge detection filter. Sensing sensitivity can be increased.

The touch recognition algorithm execution unit 30 compares the output of the edge detection filter with a predetermined threshold and determines the output data of the edge detection filter larger than the threshold as touch (or proximity) input data and detects edges lower than the threshold. The data of the filter is determined as no touch (or proximity) input or noise data. The touch recognition algorithm execution unit 30 executes a preset touch recognition algorithm, estimates a coordinate value for each touch (or proximity) input data, and outputs touch recognition result data HIDxy including coordinate information. The touch recognition algorithm may be implemented by a known touch recognition algorithm. The touch recognition result data (HIDxy) output from the touch recognition algorithm executing section 30 is transmitted to the host system. The touch recognition algorithm executing unit 30 may be implemented as an MCU (Micro Controller Unit).

The host system may be implemented as any one of a TV system, a navigation system, a DVD player, a Blu-ray player, a personal computer (PC), a home theater system, and a phone system. The host system transmits a timing signal synchronized with the data to the display timing controller 20 together with the digital video data of the input image. The host system executes an application program associated with the coordinate value of the touch data input from the touch recognition algorithm execution unit 30.

The edge detection calculation method and its effects will be described in detail with reference to FIGS. 7 to 13.

7 to 13, the edge detection mask EM is a 3x3 matrix to which coefficients are assigned, respectively. The coefficients of the edge detection mask EM include α, which gives a high weight to the data to be amplified, and β, which gives a relatively small weight to the peripheral data of the data to be amplified. In order to improve the touch (or proximity) input data value while suppressing the noise effect, α is set to a value larger than β. For example, α = 8 and β = −1 as shown in FIG. 10. The size and coefficient of the edge detection mask EM are not limited to FIG. 10. For example, the edge detection mask EM may be extended to a 4 × 4 matrix or a 5 × 5 matrix, and the central coefficient value α may be set to one or more positive coefficient values, and β may be set to 0 or a negative polarity value. .

The edge detection mask EM of the 3 × 3 matrix is mapped to and calculated from the touch row data Tdata obtained from neighboring 3 × 3 sensor nodes on the touch screen TSP, and as a result, the touch row data Tdata. ) Is amplified and shifted by one sensor node to amplify the touch row data (Tdata) sequentially by repeating the above process. After the edge detection operation on touch raw data Tdata obtained from sensor nodes connected to one line of the touch screen TSP is processed, the edge detection mask EM is shifted to the data Tdata of the next line. The process is repeated to sequentially amplify the touch row data (Tdata) obtained from the sensor nodes of the next line.

The touch raw data obtained from sensor nodes located at edges and corners of the touch screen TSP cannot be calculated with coefficients of the edge detection mask EM because neighboring data are insufficient. In consideration of this, as shown in FIGS. 9 and 10, the edge of the touch screen TSP is further extended and the dummy data DData is allocated to the virtual space as DData = 0.

[0 1 1 0 1 6 7 1 0 7 6 0 0 1 0 1] obtained from the sensor nodes positioned at the left corner of the touch screen TSP as shown in FIG. 10, of which [6 7 7 6] is touched. Assuming that the data of the input position is input to the edge detection filter, the result of the edge detection operation will be described. When the coefficient of the edge detection mask EM is α = 8 and β = -1, the edge detection calculation result [a11 a12 a13 a14 a21 a22 a23 a24 a31 a32 a33 a34 a41 a42 a43 a44] defined in FIG. 11 is as follows. Is calculated. The edge detection filter multiplies the touch row data Tdata mapped to the center coefficient α of the edge mask EM by α (*), and the touch row data mapped to the peripheral coefficient β except the center coefficient α in the edge mask EM. (Tdata) is multiplied by β, and the result is summed (+).

a11 = (0 * β) + (0 * β) + (0 * β) + (0 * β) + (0 * α) + (1 * β) + (0 * β) + (1 * β) + (6 * β) = -10

a12 = (0 * β) + (0 * β) + (0 * β) + (0 * β) + (1 * α) + (1 * β) + (1 * β) + (6 * β) + (7 * β) = -7

a13 = (0 * β) + (0 * β) + (0 * β) + (1 * β) + (1 * α) + (0 * β) + (6 * β) + (7 * β) + (1 * β) = -7

a14 = (0 * β) + (0 * β) + (0 * β) + (1 * β) + (0 * α) + (1 * β) + (7 * β) + (1 * β) + (1 * β) = -11

a21 = (0 * β) + (0 * β) + (1 * β) + (0 * β) + (1 * α) + (6 * β) + (0 * β) + (0 * β) + (7 * β) = -6

a22 = (0 * β) + (1 * β) + (1 * β) + (1 * β) + (6 * α) + (7 * β) + (0 * β) + (7 * β) + (6 * β) = 25

a23 = (0 * β) + (0 * β) + (0 * β) + (1 * β) + (0 * α) + (1 * β) + (7 * β) + (1 * β) + (1 * β) = 34

a24 = (1 * β) + (0 * β) + (1 * β) + (7 * β) + (1 * α) + (1 * β) + (6 * β) + (0 * β) + (0 * β) = -8

a31 = (0 * β) + (1 * β) + (6 * β) + (0 * β) + (0 * α) + (7 * β) + (0 * β) + (0 * β) + (1 * β) = -15

a32 = (0 * β) + (0 * β) + (0 * β) + (1 * β) + (0 * α) + (1 * β) + (7 * β) + (1 * β) + (1 * β) = 35

a33 = (0 * β) + (0 * β) + (0 * β) + (1 * β) + (0 * α) + (1 * β) + (7 * β) + (1 * β) + (1 * β) = 25

a34 = (7 * β) + (1 * β) + (1 * β) + (6 * β) + (0 * α) + (0 * β) + (0 * β) + (1 * β) + (0 * β) = -16

a41 = (0 * β) + (0 * β) + (7 * β) + (0 * β) + (0 * α) + (1 * β) + (0 * β) + (1 * β) + (0 * β) = -9

a42 = (0 * β) + (7 * β) + (6 * β) + (0 * β) + (1 * α) + (0 * β) + (1 * β) + (0 * β) + (1 * β) = -7

a43 = (7 * β) + (6 * β) + (0 * β) + (1 * β) + (0 * α) + (1 * β) + (0 * β) + (1 * β) + (1 * β) = 17

a44 = (6 * β) + (0 * β) + (0 * β) + (0 * β) + (1 * α) + (0 * β) + (1 * β) + (1 * β) + (1 * β) = -1

As can be seen from the above calculation result, the touch input data [6 7 7 6] is amplified to [25 34 35 25], while there is no touch input or the noise component is reduced. FIG. 12 is a three-dimensional graph showing the touch furnace data before the edge detection operation in FIG. 10, and FIG. 13 is a three-dimensional graph showing the touch furnace data amplified after the edge detection operation in FIG. 10. 12 and 13, the x and y axes represent sensor node positions in the x and y axis directions on the touch screen TSP, and the z axis is the touch row data Tdata value.

In order to reduce the total sensing time of the touch screen (TSP), as shown in FIGS. 14 to 23, the touch recognizable area of the touch screen (TSP) is virtually divided into blocks of a predetermined size, and after block sensing, the partial Partial sensing can optionally be performed. Block sensing is a sensing method of determining whether a touch (or proximity) input is performed by sensing voltages of sensor nodes in units of blocks. Partial sensing is a sensing method that is performed only when a touch (or proximity) input is detected by block sensing. The partial sensing checks the authenticity of the touch (or proximity) input detected by block sensing, and indicates the touch (or proximity) input position. It is a sensing method that detects precisely. Hereinafter, a block sensing method and a partial sensing method will be described with reference to FIGS. 14 to 23. Referring to the operation of the touch screen driving circuit and the touch recognition algorithm execution unit 30 in the sensing method as follows.

The Tx driving circuit 32 applies driving pulses to the Tx lines T1 to Tj in block units under the control of the timing controller 36 during the block sensing period under the control of the timing controller 36. Here, driving pulses are simultaneously applied to the Tx lines in one block. The time required for sensing sensor nodes present in one block is equal to the time required for sensing one sensor node in the prior art. Under the control of the timing controller 36, the Tx driving circuit 32 supplies a driving pulse to only the Tx lines in the block and the touch (or proximity) input only in the Tx block in which a touch (or proximity) input is detected during the partial sensing period. No driving pulse is supplied to these undetected blocks.

The Rx driving circuit 34 receives the voltages of the sensor nodes through the Rx lines R1 to Ri in block units under the control of the timing controller 36 during the block sensing period. The Rx driving circuit 34 simultaneously receives, samples, and converts the voltages of the sensor nodes in units of blocks during the block sensing period. The Rx driver circuit 34 sequentially receives, samples, and converts the voltages of the sensor nodes through Rx lines connected to the sensor nodes in the block only in a block in which a touch (or proximity) input is detected as a result of block sensing. .

The timing controller 36 is configured to set up a setup signal SUTx for setting a Tx channel for outputting a driving pulse from the Tx driving circuit 32 and an Rx channel for receiving a sensor node voltage in the Rx driving circuit 34. Generates a setup signal SURx. When the timing controller 36 determines that the touch (or proximity) input is detected by the block sensing based on the touch recognition result by the block sensing from the touch recognition algorithm execution unit 30, the timing controller 36 and the Rx driving circuit 32. While the furnace 34 is controlled in the partial sensing step, if it is determined that there is no touch (or proximity) input as a result of the block sensing, the Tx driving circuit 32 and the Rx driving circuit 34 are controlled in the block sensing step.

The touch recognition algorithm execution unit 30 inputs the touch raw data Tdata received from the Rx driver circuit 34 to the edge detection filter through block sensing to amplify the touch (or proximity) input value and reduce the noise component. . The touch recognition algorithm execution unit 30 transmits information indicating the presence or absence of a touch (or proximity) input to the timing controller 36. The touch recognition algorithm execution unit 30 inputs the touch raw data Tdata received from the Rx driver circuit 34 through the partial sensing to the edge detection filter to amplify the touch (or proximity) input value and reduce the noise component. . The touch recognition algorithm execution unit 30 analyzes the touch raw data Tdata input from the Rx driving circuit 34 as a partial sensing result by using a preset touch recognition algorithm, so that the amount of change before and after touch is greater than or equal to a predetermined threshold value. Coordinate values are estimated for each to generate touch recognition result data HIDxy including coordinate information. The touch recognition result data (HIDxy) output from the touch recognition algorithm executing section 30 is transmitted to the host system.

14 is a flowchart illustrating a touch screen driving method according to an embodiment of the present invention. 15 and 16 illustrate block sensing periods and partial sensing periods.

14 to 16, the touch screen driving method of the present invention senses sensor nodes in units of blocks during the block sensing period TB. (S1) The touch screen driving method of the present invention uses the block sensing period TB. Tx lines present in the I + 1 block after sensing the voltage of all sensor nodes present in the I block by simultaneously supplying driving pulses to the Tx lines present in the I (I is a natural number) block. The driving pulses are simultaneously applied to sense the voltages of all the sensor nodes existing in the I + 1 block. During the block sensing period TB, since the driving pulse is simultaneously applied to the Tx lines included in one block as shown in FIGS. 18, 21, and 23, the block sensing period TB is only one line sensing time of the prior art. .

The touch screen driving method of the present invention improves only touch (or proximity) input data by inputting touch row data Tdata generated through block sensing to an edge detection filter. (S1 and S2) Next, the touch screen of the present invention. The driving method compares the output data of the edge detection filter with a predetermined threshold value, and determines data larger than the threshold value as touch (or proximity) data. In the touch screen driving method of the present invention, when a touch (or proximity) input is detected through block sensing, the process proceeds to the partial sensing step and drives pulses on Tx lines formed in the block where the touch input is detected during the partial sensing period TP. Are sequentially supplied line by line to accurately sense the voltages of the sensor nodes present in the touch (or proximity) input position. (S3 and S4) If a touch (or proximity) input is not detected through the block sensing, FIG. 9 and FIG. Likewise, it does not go to the partial sensing stage.

In the touch screen driving method of the present invention, the touch row data Tdata generated through partial sensing is compared with a threshold value, and a touch recognition algorithm is executed to estimate coordinate values for each data above the threshold value.

FIG. 17A illustrates an example of input data of an edge detection filter as touch raw data Tdata generated through block sensing. FIG. 17B illustrates an example in which only touch (or proximity) input data is amplified by mapping the touch furnace data as shown in FIG. 17A with the above-described edge detection mask EM. FIG. 17C is data before input to the edge detection filter as touch row data Tdata generated through partial sensing with respect to the same touch input as shown in FIG. 17A. After the touch raw data Tdata generated through partial sensing as shown in FIG. 17C is input to the edge detection filter, a touch recognition algorithm may be executed based on the output of the edge detection filter. (S5) Since step S5 is not essential, May be omitted.

In the touch screen driving method of the present invention, the total sensing time Ttotal required for sensing all the sensor nodes in the touch screen TSP is a block sensing period as shown in FIG. 15 when a touch (or proximity) input is detected through block sensing. (TB) plus partial sensing period (TP). The block sensing period TB is always fixed at a constant time. When a touch (or proximity) input is detected in several blocks through block sensing, that is, when the multi-touch (or proximity) occurs, the number of blocks to be partial sensed increases, so that the partial sensing period TP may be long. As the number of touch (or proximity) inputs detected as a result of the block sensing increases, the partial sensing period TP becomes longer, so that the partial sensing period TP is not fixed.

If a touch (or proximity) input is not detected through block sensing, the total sensing time Ttotal required for sensing all sensor nodes in the touch screen TSP is only a block sensing period TB as illustrated in FIG. 16. As a result, the total sensing time of the present invention can be greatly reduced compared to the conventional total sensing time.

18 to 23 are diagrams illustrating various examples of block sensing and partial sensing according to various types of touch inputs. The size of the touch screen, the number of blocks, the number of Tx lines, and the number of Rx lines are not limited to FIGS. 18 to 23, and may be variously modified.

18 is a diagram illustrating an example in which a touch input is generated within one block. FIG. 19 is a waveform diagram illustrating driving pulses applied to the touch screen TSP in the example of FIG. 18.

18 and 19, the Tx driving circuit 32 may include the first to fourth Tx lines T1 ˜ to sense the first to third blocks B11 ˜ B13 during the block sensing period TB. After simultaneously applying the driving pulses P11 to P13 to T4, the driving pulses are applied to the fifth to eighth Tx lines T5 to T8 to sense the fourth to sixth blocks B21 to B23. Apply (P21 to P23) at the same time. Subsequently, the Tx driving circuit 32 simultaneously applies driving pulses P31 to P33 to the ninth to twelfth Tx lines T9 to T12 in order to sense the seventh to ninth blocks B31 to B33. do.

During the block sensing period TB, the Rx driving circuit 34 receives the voltages of the sensor nodes through the first to fourth Rx lines R1 to R4 in synchronization with the driving pulse P11 and outputs the voltage of the sensor nodes in the first block B11 Receives and samples the voltage of the existing sensor nodes and converts them into digital data. The Rx driving circuit 34 receives the voltage of the sensor nodes through the fifth to eighth Rx lines R5 to R8 in synchronization with the drive pulse P12 and receives the voltage of the sensor nodes existing in the second block B12 And converts it into digital data. The Rx driving circuit 34 receives the voltage of the sensor nodes through the ninth through twelfth Rx lines R9 through R12 in synchronization with the drive pulse P13 and receives the voltage of the sensor nodes existing in the third block B13 And converts it into digital data. The Rx driving circuit 34 receives the voltages of the sensor nodes through the first to fourth Rx lines R1 to R4 in synchronization with the drive pulse P21 and receives the voltage of the sensor nodes existing in the fourth block B21 And converts it into digital data. The Rx driving circuit 34 receives the voltages of the sensor nodes through the fifth to eighth Rx lines R5 to R8 in synchronization with the drive pulse P22 and receives the voltage of the sensor nodes existing in the fifth block B22 And converts it into digital data. The Rx driving circuit 34 receives the voltage of the sensor nodes through the ninth through twelfth Rx lines R9 through R12 in synchronization with the drive pulse P23 and receives the voltage of the sensor nodes existing in the sixth block B23 And converts it into digital data. The Rx driving circuit 34 receives the voltage of the sensor nodes through the first to fourth Rx lines R1 to R4 in synchronization with the drive pulse P31 and receives the voltage of the sensor nodes existing in the seventh block B31 And converts it into digital data. The Rx driving circuit 34 receives the voltage of the sensor nodes through the fifth to eighth Rx lines R5 to R8 in synchronization with the drive pulse P32 and receives the voltage of the sensor nodes existing in the eighth block B32 And converts it into digital data. The Rx driving circuit 34 receives the voltage of the sensor nodes through the ninth through twelfth Rx lines R9 through R12 in synchronization with the drive pulse P33 and receives the voltage of the sensor nodes existing in the ninth block B33 And converts it into digital data.

As a result of the block sensing, when a touch (or proximity) input is detected in the fifth block B22 as shown in FIG. 18, the process proceeds to the partial sensing step. In the partial sensing step, the Tx driving circuit 32 sequentially drives driving pulses only to the fifth to eighth Tx lines T5 to T8 connected to the sensor nodes of the fifth block B22 during the partial sensing period TP. Is authorized. The Rx driving circuit 34 sequentially receives the voltages of the sensor nodes in synchronization with the driving pulses applied to the Tx lines T5 to T8 during the partial sensing period TP, thereby detecting a touch (or proximity) input. Sensing the voltage of sensor nodes precisely within

20 is a diagram illustrating an example in which a touch input is generated at a boundary between neighboring blocks. FIG. 21 is a waveform diagram illustrating driving pulses applied to the touch screen TSP in the example of FIG. 20.

20 and 21, the block sensing method is substantially the same as the above-described embodiment of FIGS. 18 and 19. As shown in FIG. 20, when a touch (or proximity) input is generated between the fifth block B22 and the sixth block B23, a touch (or proximity) input is detected in all of the blocks B22 and B23 as a result of block sensing. The process of partial sensing is carried out. In the partial sensing step, the Tx driving circuit 32 sequentially drives driving pulses only to the Tx lines T5 to T8 connected to the sensor nodes of the fifth and sixth blocks B22 and B23 during the partial sensing period TP. Is authorized. The Rx driving circuit 34 is connected to the sensor nodes of the fifth and sixth blocks B22 and B23 in synchronization with driving pulses applied to the Tx lines T5 to T8 during the partial sensing period TP. The voltages of the sensor nodes are sequentially received through the signals R5 to R12 to precisely sense the voltages of the sensor nodes in blocks in which a touch (or proximity) input is detected. As a result of the partial sensing, a single touch (or proximity) input generated at the boundary between the fifth and sixth blocks B22 and B23 is recognized.

22 is a diagram illustrating an example of generating a multi-touch input. FIG. 23 is a waveform diagram illustrating driving pulses applied to the touch screen TSP in the example of FIG. 22.

22 and 23, the block sensing method is substantially the same as the above-described embodiment of FIGS. 18 and 19. As a result of the block sensing, a touch (or proximity) input is detected at the first block B11 and the fifth block B22 as shown in FIG. 22, and the process proceeds to the partial sensing step. In the partial sensing step, the Tx driving circuit 32 sequentially drives driving pulses only to the Tx lines T1 to T8 connected to the sensor nodes of the first and fifth blocks B11 and B22 during the partial sensing period TP. Is authorized. The Rx driving circuit 34 is connected to the sensor nodes of the first and fifth blocks B11 and B22 in synchronization with driving pulses applied to the Tx lines T1 to T8 during the partial sensing period TP. The voltages of the sensor nodes are sequentially received through the signals R1 to R8 to accurately sense the voltages of the sensor nodes in blocks in which a touch (or proximity) input is detected. As a result of the partial sensing, the multi-touch (or proximity) input generated in the first and second blocks B11 and B22 is recognized.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification, but should be defined by the claims.

DIS: Display panel TSP: Touch screen
12: data driving circuit 14: scan driving circuit
20: display timing controller 30: touch recognition algorithm execution unit
32: Tx driving circuit 34: Rx driving circuit
36: Touch (Rx, Tx) Timing Controller

Claims (14)

A touch screen including a touch recognizable area including Tx lines, Rx lines intersecting the Tx lines, and sensor nodes formed at intersections of the Tx lines and the Rx lines; A touch screen including a touch screen driving circuit for applying a driving pulse and receiving the voltage of the sensor nodes through the Rx lines in synchronization with the driving pulse, sampling the received voltage, converting the received voltage into digital data, and generating touch-to-data. In the data processing method of,
An edge detection calculation step of mapping a preset edge detection mask to the touch furnace data to multiply the coefficients of the edge detection mask by the touch furnace data and sum the results; And
Estimating a coordinate for each touch input generated on the touch screen based on a result of the edge detection operation. The method of claim 1,
The edge detection mask,
A first coefficient set at the center of the edge detection mask; And
A second coefficient set around the edge of the edge detection mask other than the center;
And wherein the first coefficient is a positive polarity value, and the second coefficient is a negative polarity value. 3. The method of claim 2,
Among the touch raw data obtained from the sensor nodes present in the same size as the edge detection mask, the central data located in the center is multiplied by the first coefficient,
Peripheral data other than the center data among the touch raw data obtained from the sensor nodes existing within the same size as the edge detection mask are multiplied by 1: 1 with the second coefficient,
And a sum of the center data multiplied by the first coefficient and the peripheral data multiplied by the second coefficient is calculated as the edge detection calculation result data for the center data. A touch recognizable area including Tx lines, Rx lines intersecting the Tx lines, and sensor nodes formed at intersections of the Tx lines and the Rx lines, wherein the touch recognizable area is at least two blocks; A touch screen divided into a plurality of lines, and applying a driving pulse to the Tx lines, receiving voltages of the sensor nodes through the Rx lines in synchronization with the driving pulses, sampling the received voltage, and converting the converted voltage into digital data. In the data processing method of the touch screen including a touch screen driving circuit for generating raw data,
Generating data with a first touch by sensing sensor nodes of blocks divided in a touch recognition region of the touch screen in units of blocks;
Generating a second touch furnace data by precisely sensing sensor nodes within the block in which the touch input is detected when it is determined that a touch input is detected based on the analysis result of the first touch furnace data;
An edge detection calculation step of mapping a predetermined edge detection mask to the first touch furnace data to multiply the coefficients of the edge detection mask by the first touch furnace data and add the results; And
And determining whether there is a touch input generated on the touch screen based on a result of the edge detection operation. The method of claim 4, wherein
And estimating a coordinate for each of the second touch input data after the edge detection operation after performing the edge detection operation on the second touch furnace data. The method of claim 4, wherein
The edge detection mask,
A first coefficient set at the center of the edge detection mask; And
A second coefficient set around the edge of the edge detection mask other than the center;
And wherein the first coefficient is a positive polarity value, and the second coefficient is a negative polarity value. The method according to claim 6,
Among the touch data obtained from the sensor nodes existing within the same size as the edge detection mask, the central data located at the center is multiplied by the first coefficient,
Peripheral data other than the center data among the touch data obtained from the sensor nodes present in the same size as the edge detection mask are multiplied by 1: 1 with the second coefficient,
And a sum of the central data multiplied by the first coefficient and the peripheral data multiplied by the second coefficient is calculated as data after an edge detection operation on the central data. A touch screen including a touch recognizable area including Tx lines, Rx lines intersecting the Tx lines, and sensor nodes formed at an intersection of the Tx lines and the Rx lines;
A touch screen driving circuit which applies a driving pulse to the Tx lines, receives the voltages of the sensor nodes through the Rx lines in synchronization with the driving pulses, samples the received voltage, and converts the received voltage into digital data to generate touch-through data. in; And
By mapping a preset edge detection mask to the touch furnace data, coordinates for each touch input generated on the touch screen are based on an edge detection operation result of multiplying coefficients of the edge detection mask by the touch furnace data and adding the results. And a touch recognition algorithm execution unit for estimating. The method of claim 8,
The edge detection mask,
A first coefficient set at the center of the edge detection mask; And
A second coefficient set around the edge of the edge detection mask other than the center;
Wherein the first coefficient is a positive polarity value, and the second coefficient is a negative polarity value. The method of claim 9,
Among the touch data obtained from the sensor nodes existing within the same size as the edge detection mask, the central data located at the center is multiplied by the first coefficient,
Peripheral data other than the center data among the touch data obtained from the sensor nodes present in the same size as the edge detection mask are multiplied by 1: 1 with the second coefficient,
And a sum of the central data multiplied by the first coefficient and the peripheral data multiplied by the second coefficient is calculated as data after an edge detection operation on the central data. And a touch recognizable area including Tx lines, Rx lines intersecting the Tx lines, and sensor nodes formed at intersections of the Tx lines and the Rx lines, wherein the touch recognizable area includes at least two A touch screen divided into blocks;
A touch screen driving circuit which applies a driving pulse to the Tx lines, receives the voltages of the sensor nodes through the Rx lines in synchronization with the driving pulses, samples the received voltage, and converts the received voltage into digital data to generate touch-through data. in; And
By mapping a preset edge detection mask to the touch furnace data, coordinates for each touch input generated on the touch screen are based on an edge detection operation result of multiplying coefficients of the edge detection mask by the touch furnace data and adding the results. A touch recognition algorithm execution unit for estimating,
The touch screen driving circuit includes:
The sensor nodes of the divided blocks in the touch recognition possible area of the touch screen are sensed in units of blocks to output data by a first touch, and it is determined that a touch input is detected based on an analysis result of the first touch furnace data. When the touch input is detected, the sensor nodes in the block are sensed precisely and data is output to the second touch.
And the touch recognition algorithm execution unit performs edge detection on the first touch furnace data to determine the presence or absence of a touch input. The method of claim 11,
And the touch recognition algorithm execution unit estimates coordinates for each of the second touch input data after the edge detection operation after performing the edge detection operation on the second touch furnace data. The method of claim 11,
The edge detection mask,
A first coefficient set at the center of the edge detection mask; And
A second coefficient set around the edge of the edge detection mask other than the center;
Wherein the first coefficient is a positive polarity value, and the second coefficient is a negative polarity value. The method of claim 13,
Among the touch data obtained from the sensor nodes existing within the same size as the edge detection mask, the central data located at the center is multiplied by the first coefficient,
Peripheral data other than the center data among the touch data obtained from the sensor nodes present in the same size as the edge detection mask are multiplied by 1: 1 with the second coefficient,
And a sum of the central data multiplied by the first coefficient and the peripheral data multiplied by the second coefficient is calculated as data after an edge detection operation on the central data.

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