KR101462283B1 - Electrocardiogram measurement method and apparatus - Google Patents

Abstract

The present invention relates to an electrocardiogram measuring apparatus, which comprises a transparent insulator protective film panel and a plurality of transparent electrodes which form a capacitance on a contact surface when contact occurs with the transparent insulator protective film, A current is applied to the transparent electrode panel, and as the transparent conductive electrode panel is brought into contact with the transparent electrode panel, the electrode having the capacitance of the plurality of transparent electrodes is sensed to grasp the two independent contact regions Measuring a capacitance of each of the two contact areas in real time, calculating a difference between the two measured capacitances, determining a voltage difference according to the calculated capacitance difference, Signal.

Electrocardiography, capacitance, capacitance difference

Description

ELECTROCARDIOGRAM MEASUREMENT METHOD AND APPARATUS [0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for measuring an electrocardiogram (ECG), and more particularly, to a method and apparatus for measuring an electrocardiogram using a touch screen.

Electrocardiogram signal detection method that is basic for heart condition and various health condition measurement is a typical detection method using a 2-pole or 3-pole electrode. Such an electrode detection method can be classified into a case of using a disposable gel type electrode and a case of using a dry type electrode using a conductor depending on the electrode type.

Since a dual gel type electrode can obtain a signal stably, an electrocardiogram measuring instrument equipped with a gel type electrode is mainly used in a medical institution.

The electrodes of the conductor are typically mounted on a portable electrocardiograph. The electrocardiogram measuring device obtains the final electrocardiogram signal by amplifying and processing the voltage difference between the electrodes measured through the electrodes through a device such as a high-impedance amplifier.

Recently, in order to eliminate the inconvenience of the electrode, an electrocardiogram measuring method using an electro-potential sensor has appeared. This method is a method of measuring an electric field change around the body by using a capacitance coupling electrode. That is, in the electrocardiogram measuring method using the electric potential sensor, a capacitance pickup electrode and an electrode having a high dielectric constant are thinly coated on the electrode to generate a capacitance between the skin contact surface and the electrode, and a displacement current ) Is measured using a high-impedance amplifier and various noise reduction techniques to measure the same signal as the electrocardiogram (Prance RJ, An Ultra-low-noise electrical-potential probe for human-body scanning, (2000) Meas. Sci Technol. 11, 1-7)

However, the electrocardiogram measuring method using the gel type electrode may cause problems such as skin rash according to the skin condition of the user when using the disposable gel type electrode, and lead-wire from the electrode to the body of the electrocardiograph measuring instrument is connected There is an inconvenience in carrying.

In the electrocardiogram measuring method using the electrodes of the conductor, since the conductor electrode must be placed in the portable device, the appearance of the product is restricted.

In the electrocardiogram measuring method using an electro-potential sensor, since it is necessary to measure very small displacement current, it is susceptible to various noises. Therefore, guard treatment between the capacitance coupling electrode and the measuring circuit, Additional effort such as active grounding of the measurement circuitry is required.

In order to solve the above-described problems, the present invention provides a method and an apparatus for measuring an electrocardiogram in which no abnormality occurs in a contact portion on the body during measurement.

The present invention provides a method and apparatus for measuring electrocardiogram which are resistant to various noises and can be easily implemented.

The present invention can overcome disadvantages such as skin problems and limitations of portable devices installed in existing gel and conductor electrodes by measuring electrocardiogram using a capacitive touch sensor array applied to portable terminals, By using the ring electrode, the electrocardiogram can be relatively easily measured. Also, since the present invention can be measured in a portable terminal equipped with a capacitive touch screen, measurement and measurement value visualization are possible at the same time. In addition, in the case of a touch screen, since the touch sensor is already arranged, there is no need to add an electrode at the time of designing. Unlike the displacement current measurement method used when using the conventional capacitance coupling electrode method, the present invention can simplify the circuit using the capacitance change measurement method by the electric field difference in the body.

Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. It is to be noted that the same components in the drawings are denoted by the same reference numerals and symbols as possible even if they are shown in different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

The present invention proposes a method of measuring electrocardiogram using a touch screen implemented by a capacitive method. There is a voltage difference between the hands due to the electric field difference in the body. Therefore, when the left and right fingers touch the electrodes of the capacitive touch screen, the capacitance between the fingers and the electrodes will be different. The present invention detects the difference in capacitance, extracts a voltage difference between two hands which varies with time, and measures the electrocardiogram using the extracted voltage difference.

FIG. 1 shows an embodiment of a configuration of an electrocardiogram measuring apparatus to which the present invention is applied. 1, an electrocardiogram measuring apparatus according to an embodiment of the present invention includes a controller 10, a touch screen management unit 20, a touch screen panel 30, a display unit 40, and a wireless communication unit 50 do.

The wireless communication unit 50 transmits and receives wireless signals to and from the mobile communication base station through an antenna. The radio communication unit 50 processes baseband signals to be transmitted, which are input from the control unit 10, and then modulates the baseband signals into radio signals, transmits them through the antennas, demodulates the radio signals received through the antennas, And provides the control unit 10 with the control signal.

The display unit 40 displays various data and information received from the base station or data stored in the memory unit 60 on a display panel such as an LCD under the control of the control unit 10. [ In the case of a terminal equipped with a touch screen, the display panel is positioned at the lower end of the touch screen panel 30, and the operation of the touch screen and the display operation are interlocked with each other.

The memory unit 60 stores a program for processing and controlling the control unit 10, reference data, various updatable storage data, and the like, and is provided as a working memory of the control unit 10.

2, the touch screen panel 30 includes a transparent upper substrate 31 and a protective film 32 which is a transparent electrode panel on which the transparent electrodes 33 and 34 intersecting the row and the column are formed. . Here, the upper substrate 31 may be a nonconductive protective film, and the transparent electrodes 33 and 34 may be formed using indium tin oxide (ITO). Since the structure of the capacitive touch screen panel 30 is a well-known technology, a detailed description thereof will be omitted.

The touch screen management unit 20 operates by separating the touch screen mode and the electrocardiogram specific mode under the control of the control unit 10 and includes a driver for the touch screen panel 30 and a sensor driving IC. According to the embodiment of the present invention, the driver and the sensor driving IC for the touch screen panel 30 may be independently implemented according to the touch screen and the electrocardiogram, respectively, or may be integrally implemented without any separate use.

For example, the touch screen management unit 20 may be configured as shown in FIG. 7, the touch screen management unit 20 may include an electrocardiogram driving IC / electrocardiogram sensor 301, a touch screen driver 302, a touch screen driving IC 303, and a touch screen sensor 304 . Under the control of the control unit 10, the touch screen management unit 20 performs a general touch screen operation by connecting the touch screen driver 302 and the touch screen sensor 304 to the touch screen panel when the touch screen mode is selected. In the electrocardiogram measurement mode, the touch screen panel and the electrocardiogram driving IC / electrocardiograph sensor 301 are connected to perform an operation for electrocardiogram measurement. According to another embodiment of the present invention, the electrodes of the touch screen driver 302 and the touch screen sensor 304 may be the same.

The touch screen management unit 20 applies an AC current to the touch screen panel 30 and the touch screen panel 30 allows the applied AC current to flow to the four corners of the touch screen panel 30. [ In this state, when a hand of a person is touched to the touch screen panel 30, current flows to the ground through the human body, and the touch screen management unit 20 can sense the current flow. The touch screen management unit 20 can sense an electrode where a current flows on the touch screen panel 30 and thereby can grasp a touch area where a touch is generated by a person on the touch screen panel 30. [ If the touch screen mode is set, the touch screen management unit 20 performs a general touch screen control / management operation under the control of the control unit 10. [

In the electrocardiogram measurement mode, the touch screen management unit 20 according to the present invention operates as follows. When the user places the fingers of both hands on the touch panel 30 in a state where the electrocardiogram measurement mode is set according to the embodiment of the present invention, the touch screen management unit 20 controls the touch screen management unit 20, And the electrostatic capacitance generated at each electrode belonging to the contact area is measured. The touch screen management unit 20 calculates the voltage difference according to the capacitance difference between the two contact areas, and converts the voltage difference into the electrocardiogram output. At this time, in order to recognize the contact region as two independent contact regions, there must be a predetermined minimum interval between the two contact regions, and the touch screen management unit 20 recognizes the number of contact regions according to the existence of the minimum interval do.

The principle that the touch screen management unit 20 measures the voltage difference between the two hands for electrocardiogram measurement according to the present invention will be described with reference to FIGS. 3 and 4. FIG. 3 is a diagram showing the principle of electrical equivalent modeling and voltage difference measurement when the fingers of the right hand and the left hand are brought into contact with each other at regular intervals on the capacitive touch screen panel 30 according to an embodiment of the present invention to be. 4A is a graph showing the timings of the SW1 107 and the SW2 108, FIG. 4B is a voltage value measured according to the timing graph of FIG. 4A, R) time constant, and FIG. 4D is a graph showing a difference in capacitance measurement value due to a time difference between the left (L) and right (R) time constants.

FIG C _s (103, 104) from 3 represents the capacitance of the contact area formed on the touch screen panel 30 when the finger on the touch screen panel 30, C _{s, L} (103) is left C _{s, R} (104) is the capacitance of the contact area due to the right finger contact.

C _t (101, 102) is to represent the capacitance formed between on the contact region and the finger touch screen panel 30 when the finger on the touch screen panel 30, Ct, _L (101) is on the left finger And C _{t, R} (102) are the capacitances corresponding to the right fingers. V _ECG 112 represents the potential difference between the left hand and right hand formed by the heartbeat and C _G 105 represents the coupling capacitance between the right leg and the earth ground and C _k (106) represents the coupling capacitance between the touch screen management unit (20) and the ground earth.

Generally, the coupling capacitance of C _G (105) and C _k (106) is about 7mF. The capacitances of C _s (103,104) and C _t (101,102) are in pF units. When the charging current is supplied in cycles of several tens of kHz for measurement of capacitance change, C _G (105), C _k ), The complex impedance is relatively small, so it can be said that it is substantially shorted to ground earth (Kawarada, et al., Proceedings of the 22nd Annual EMBS International Conference, Chicago, 2000.)

The touch screen management unit 20 includes a switch controller 21 and a measurement unit 22 and controls the switching of the first switch SW1 107 and the second switch SW2 108 and controls the switching of the touch screen panel 0.0 > 30 < / RTI >

When the first switch SW1 107 is short-circuited to the first channel ch1 and the second switch SW2 108 shorts to the power source 111, the power source of V _c is supplied to the contact area of the left finger, Charges are accumulated in C _{s, L} (103) and C _{t, L} (101). The accumulated charge amount Q _sw1 is expressed by the following equation (1).

Q _sw1 = C _sL V _c + C _tL (V _c -V _ECG )

When the charging is completed, the SW2 108 is short-circuited to the pickup resistor R (109) to cause a discharge. At this time, the voltmeter 110 measures the voltage during discharge and measures the time constant to measure the capacitance value. The measured capacitance C _mL can be expressed by the following equation (2).

C _mL = C _sL + C _tL - C _tL (V _ECG / V _c )

Then, when the SW1 107 is short-circuited to the second channel ch2 and the SW2 108 is short-circuited to the power source and the power source of V _c is supplied to the contact area of the right finger, C _{s, R} 104 and C _{t, R} And the accumulated charge amount Q _sw2 is expressed by Equation (3).

Q _sw2 = C _sR V _c + C _tR V _c

After the charging is completed, the SW2 108 is short-circuited to the pickup resistor R (109) to cause a discharge. At this time, a voltage during discharging is measured by the voltmeter 110, and a capacitance value can be measured by measuring a time constant. The measured capacitance C _mR is expressed by Equation (4).

C _mR = C _sR + C _tR

Substantially C _{s, L} (103) and C _{s, R} (104) are controlled at the time of electrode fabrication and may have a similar size depending on the degree of processing, Since the areas of the two contact surfaces formed by the finger contact are formed in a similar size, C _{t, L} (101) and Since C _{t, R} (102) can also have similar sizes, the difference ΔC between C _mL and C _mR can be approximated as shown in equation (5).

C = _Ct (V _ECG / V _c )

Thus, ΔC is proportional to the V _ECG to be finally measured. Therefore, the present invention can measure the V _ECG between both hands varying with time by measuring? C that changes with time.

For reference, when the size of the V _ECG is about 1 mV and the supply voltage is 1 V, the magnitude of V _ECG / V c is 1 × 10 ^-3 and C _t is the unit of pF. Therefore, the actually measured? C is a very small amount of about fF. Accordingly, in the embodiment of the present invention, the PS021 of "acem messelectronic GmbH" which can measure the difference up to aF can be used.

The touch screen management unit 20 outputs the capacitance of each contact area measured by the above-described principle to the control unit 10. The control unit 10 calculates the difference? C using the two electrostatic capacities inputted, and grasps the voltage difference V _ECG between the hands using? C. Then, the control unit 10 changes the detected V _ECG to an electrocardiogram output and displays it on the display unit 40.

The operation of the electrocardiogram measuring apparatus constructed as above is shown in FIG. Referring to FIG. 5, the controller 10 of the electrocardiogram measuring apparatus checks whether there is a request for setting an ECG measurement mode in relation to the touch screen in step 201. FIG. The user can set the electrocardiogram measurement mode through menu selection or the like. If there is a request for setting the electrocardiogram measurement mode, the control unit 10 proceeds to step 205. If there is a request for setting the electrocardiogram measurement mode other than the electrocardiogram measurement mode setting request, In step 203, the controller 10 controls the touch screen management unit 20 to perform a general touch screen operation.

The user inputs a request for setting an electrocardiogram measurement mode through a menu selection or the like, and then contacts his or her hands to a proper position on the touch screen panel 30. [ For example, the thumbs of both hands can be placed on the touch screen panel 30 by wrapping the electrocardiogram measuring device as shown in FIG.

When a finger is touched on the touch screen panel 30, the capacitance of the contact area corresponding to the contact area of the touch screen panel 30 with the finger is changed, so that the touch screen management unit 20 detects that the contact has occurred And the contact area can also be grasped. At this time, the touch screen management unit 20 detects that there are two independent contact areas when there is a minimum gap between the contact areas, and detects the positions of the two contact areas and outputs them to the control unit 10. In step 205, the controller 10 determines two contact areas. Then, in step 207, the control unit 10 displays a basic electrocardiogram screen between two detected contact areas as shown in FIG. The basic electrocardiogram screen may include information related to the outline of the electrocardiogram display area 230 in which the electrocardiogram signal is displayed and the electrocardiogram. The size of the electrocardiogram display area 230 may be fixed according to the embodiment of the present invention or may be adjusted in proportion to the interval of the two contact areas. That is, the controller 10 can determine the size of the electrocardiogram display area 230 so that the electrocardiogram display area 230 can be inserted between the two contact areas according to the interval between the two contact areas. And the position of the electrocardiogram display area 230 is also determined to be located between the two contact areas. The position of the electrocardiogram display area 230 can be changed according to the positions of the two contact areas even when the size of the electrocardiogram display area 230 is fixed. Or may have a fixed position irrespective of the position of the contact area.

Then, in steps 209 to 211, the touch screen management unit 20 measures the electrostatic capacitance of each contact area that is changed according to time, and outputs the measured capacitance to the control unit 10. The controller 10 calculates the voltage difference according to the difference between the electrostatic capacitances at the same point in step 211 and proceeds to step 213 to convert the voltage difference into the electrocardiogram output. The controller 10 displays the electrocardiogram signal 240 of the electrocardiogram display area 230.

Thus, the user can intuitively and conveniently check his electrocardiogram. The electrocardiographic information may be stored in the memory unit 60 as data and transmitted to a specific external destination through a wireless communication unit 50 or the like. The external transmission of ECG information may be performed simultaneously with the ECG measurement.

The touch screen management unit 20 may be configured differently from the touch screen management unit 20 according to another embodiment of the present invention. This is shown in Fig.

FIG. 8 shows a method for implementing a capacitive touch screen by scanning an electrode array using a high-performance capacitance meter such as PS021 (acem messelectronic gmbh) used for electrocardiogram measurement. And the function unit can be integrated and configured. Accordingly, the touch screen management unit 20 may include a driver 312, a sensor 313, and an integrated driving IC 311 operating in both a touch screen operation mode and an electrocardiogram measurement mode.

9 is a view for explaining a method of using capacitance measurement values in a plurality of unit cells for electrocardiogram measurement when the contact area by the finger is larger than the capacitance measurement unit cell. When the electrostatic capacity is measured in pixel-by-pixel manner in the electrostatic capacitance type electrode array, the contact area (ROA L) corresponding to the left hand and the contact area (ROA R) corresponding to the right hand are alternately measured. Using the method of accumulating the comparison values of the two contact areas, it is possible to measure the difference between the left hand and the right hand at the same time as possible. 9, electrode 1, electrode 2, electrode 3, electrode 4, electrode 5, and electrode 6 are included in the left-hand contact area ROA L, 2 ', the electrode 3', the electrode 4 ', the electrode 5', and the electrode 6 ', the capacitance difference can be measured by matching the corresponding electrodes one by one. The electrostatic capacitance difference between the electrodes is finally added to measure the capacitance difference between the left-hand contact region ROA L and the right-hand contact region ROA R.

Alternatively, the capacitance may be measured in a block-to-block manner in a capacitive electrode array. That is, the capacitance corresponding to the left-hand-side contact area ROA L is calculated, the capacitance corresponding to the right-hand contact area ROA R is calculated, and the difference between the two capacitances is calculated, Measure the difference.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. For example, although the position of the electrocardiogram display area 230 can be changed according to the contact area in the above embodiment, the position of the electrocardiogram display area 230 may be fixed. Accordingly, when the electrocardiogram measurement mode is set, the electrocardiogram display area 230 may be displayed first so that the user may place the finger in consideration of the electrocardiogram display area 230. The touch screen management unit 20 may be included in the control unit 10. Therefore, the scope of the present invention should not be limited by the described embodiments but should be determined by the equivalents of the claims and the claims.

1 is a block diagram illustrating a configuration of an electrocardiogram measuring apparatus according to an embodiment of the present invention;

2 illustrates a structure of a touch screen panel according to an exemplary embodiment of the present invention.

FIG. 3 is a diagram illustrating an electric equivalent modeling model and a voltage difference measurement principle when a finger of a right hand and a left hand are brought into contact with each other at regular intervals on a capacitive touch screen panel according to an embodiment of the present invention.

Figures 4A-4D show graphs showing various measurements,

5 is a flowchart illustrating an operation of an electrocardiogram measuring apparatus according to an embodiment of the present invention.

6 is a perspective view of an electrocardiogram measuring apparatus according to an embodiment of the present invention,

FIG. 7 and FIG. 8 are views illustrating the configuration of a touch screen management unit according to an embodiment of the present invention.

9 is a diagram illustrating a capacitance measurement method according to an embodiment of the present invention.

Claims (10)

An electrocardiogram measuring apparatus comprising: A transparent insulator protective film panel, A plurality of transparent electrodes arranged on the contact surface to form a capacitance when the transparent insulation layer is in contact with the transparent insulation layer, a transparent electrode panel disposed under the transparent insulation layer, A current is applied to the transparent electrode panel, and as the transparent conductive electrode panel is brought into contact with the transparent electrode panel, the electrode having the capacitance of the plurality of transparent electrodes is sensed to grasp two independent contact areas, And a controller for calculating a difference between the measured capacitance and a voltage difference according to the calculated capacitance difference and changing the voltage difference to an electrocardiogram signal And an electrocardiogram measuring device. The display device according to claim 1, further comprising a display unit positioned below the transparent electrode panel and displaying data under the control of the control unit,  Wherein the controller displays the electrocardiogram signal on the display unit in real time. 3. The apparatus of claim 2, further comprising a wireless transmission unit for performing wireless communication under the control of the control unit, Wherein the control unit stores the electrocardiogram signal in a memory unit and transmits the electrocardiogram signal to a designated destination through the wireless communication unit. And a transparent electrode panel disposed on a lower portion of the transparent insulator protective film panel, wherein the plurality of transparent electrodes are arranged to form a capacitance on a contact surface when the transparent insulator protective film is in contact with the transparent insulator protective film panel, In the measuring method, The method comprising the steps of: sensing an electrode having a capacitance among the plurality of transparent electrodes when a contact occurs in a transparent insulator protective film panel provided in the electrocardiogram measuring device, Measuring a capacitance of each of the two contact regions in real time and calculating a difference between the two measured capacitances; Determining a voltage difference according to the calculated capacitance difference, and changing the voltage difference to an electrocardiogram signal. 5. The method of claim 4, further comprising displaying the electrocardiogram signal in real time on a display unit located below the transparent electrode panel. 6. The method of claim 5, further comprising the step of storing the electrocardiogram signal in a memory unit and transmitting the electrocardiogram signal to a designated destination through a wireless communication unit performing wireless communication. An electrocardiogram measuring apparatus comprising: A capacitive touch screen panel including a plurality of transparent electrodes arranged on a contact surface in contact with the transparent insulator protective film and having a transparent electrode panel disposed under the transparent insulator protective film panel, A touch panel is formed on the touch panel, and a transparent electrode layer is formed on the touch panel, and the transparent electrode layer is formed on the touch panel. A touch screen management unit for measuring the capacitance, And a control unit for calculating a difference between the measured two electrostatic capacitances inputted from the touch screen management unit, determining a voltage difference according to the calculated electrostatic capacitance difference, and changing the voltage difference to an electrocardiogram signal . 8. The touch screen display device according to claim 7, further comprising a display unit positioned below the touch screen panel and displaying data under the control of the control unit,  Wherein the controller displays the electrocardiogram signal on the display unit in real time. 9. The apparatus of claim 8, wherein the controller determines a size and a position of the electrocardiogram display area in which the electrocardiogram signal is displayed according to an interval between the two contact areas. The apparatus of claim 8, wherein the size and position of the electrocardiogram display area in which the electrocardiogram signal is displayed are predetermined.

Images