APPARATUS FOR MEASURING BIOMETRIC INFORMATION

Abstract

The present disclosure relates to a body-attachable apparatus for measuring biometric information and, more particularly, to an apparatus for measuring biometric information, which can accurately measure biometric information by connecting an additional impedance to a sensor to reduce the magnitude of noise generated during deformation or movement of the sensor, and accurately measure the biometric information by removing noise affecting a response signal during the deformation or movement of the sensor, via the additional impedance.

Claims

1. An apparatus for measuring biometric information, the apparatus comprising: a sensor including a bioelectrode configured to be insertable into skin; a measurement module configured to apply a measurement power to the bioelectrode and measure the biometric information based on a response signal received from the bioelectrode; and a load unit configured to add an additional impedance to a sensor impedance of the sensor to relatively reduce a level of noise applied to the response signal by physical deformation of the sensor, wherein a level of the additional impedance is greater than a level of the sensor impedance.

2. The apparatus for measuring biometric information according to claim 1, wherein: the bioelectrode comprises a working electrode and a reference electrode, and the load unit is connected in series with the working electrode, or is connected in series with the reference electrode, or is connected in series with the working electrode and the reference electrode, respectively.

3. The apparatus for measuring biometric information according to claim 2, wherein the load unit is arranged in series with the bioelectrode inside a housing of the measurement module.

4. The apparatus for measuring biometric information according to claim 2, wherein the load unit is formed at a body of the sensor and is formed as a tracer electrically connecting the bioelectrode and the measurement module.

5. The apparatus for measuring biometric information according to claim 2, wherein: the sensor and the measurement module are coupled separably to each other, and the load unit is formed as a connection terminal electrically connecting the sensor and the measurement module to each other when the sensor and the measurement module are coupled.

6. The apparatus for measuring biometric information according to claim 3, wherein the measurement module further comprise a low frequency band pass filter configured to filter a high frequency component of the noise from the response signal of which the level of the noise is reduced by the load unit.

7. The apparatus for measuring biometric information according to claim 3, wherein the load unit is a resistor of 10 KΩ to 10 GΩ.

8. The apparatus for measuring biometric information according to claim 3 , wherein: the measurement module comprises a temperature sensor configured to measure a temperature of the load unit or a temperature around the load unit, and the biometric information is measured from the response signal considering the additional impedance of the load unit that is changed according to the temperature measured by the temperature sensor.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] FIG. 1 is a schematic diagram for illustrating a body attachable type continuous biometric information measurement system according to an embodiment of the present disclosure.

[0026] FIG. 2 is a diagram for illustrating an applicator for attaching a biometric information measurement apparatus to a human body according to an embodiment of the present disclosure.

[0027] FIG. 3 is a diagram for illustrating an Randles equivalent circuit of a sensor.

[0028] FIG. 4 is a functional block diagram for illustrating a biometric information measurement apparatus that can reduce the size of noise generated by movement of a sensor according to an embodiment of the present disclosure.

[0029] FIG. 5 is a diagram for explaining an example of connecting a load in a biometric information measurement device according to the present disclosure.

[0030] FIG. 6 is a diagram for explaining an example of a bioelectrode measurement apparatus according to the present disclosure.

[0031] FIG. 7 is a diagram for explaining another example of a biometric information measurement apparatus according to the present disclosure.

[0032] FIG. 8 is a diagram for explaining another example of a biometric information measurement apparatus according to the present disclosure.

[0033] FIG. 9 is a diagram for explaining another example of a biometric information measurement apparatus according to the present disclosure.

DESCRIPTION OF EMBODIMENTS OF DISCLOSURE

[0034] The technical terms used in the present disclosure are only for the purpose of describing exemplary embodiments, and they are not intended to limit the present invention.

[0035] Also, unless otherwise defined, all technical terms used herein should be construed as having the same meaning as commonly understood by those skilled in the art, and should not be interpreted as being excessively inclusive or excessively restrictive. In addition, when a technical term used herein is an erroneous technical term that does not accurately represent the idea of the present invention, it should be understood as replacing the term by a technical term which can be properly understood by those skilled in the art.

[0036] Further, singular expressions used in the present specification include plural expressions unless they have definitely opposite meanings. In the present application, it shall not be construed that terms, such as “including” or “comprising”, various constituent elements or steps described in the specification need to be all essentially included, and it shall be construed that some constituent elements or steps among the various constituent elements or steps may be omitted, or additional constituent elements or steps may be further included.

[0037] Also, it should be noted that the accompanying drawings are merely illustrated to easily explain the spirit of the invention, and therefore, they should not be construed to limit the spirit of the invention by the accompanying drawings.

[0038] Hereinafter, with reference to the enclosed drawings, a body attachable type biometric information measurement apparatus according to an embodiment of the present disclosure is described in detail.

[0039] FIG. 1 is a schematic diagram for illustrating a body attachable type continuous biometric information measurement system according to an embodiment of the present disclosure.

[0040] Referring to FIG. 1, the continuous biometric information measurement system according to an embodiment of the present disclosure comprises a biometric information measurement apparatus (10) and a communication terminal (30).

[0041] The biometric information measurement apparatus (10) includes a sensor having a bioelectrode configured to be insertable into the body and a measuring module configured to measure biometric information based on a response signal received from the bioelectrode. When the biometric information measurement apparatus (10) is attached to the body, the bioelectrode of the sensor is inserted into the skin to generate an electrochemical reaction and generates a response signal, and the measurement module measures biometric information such as blood glucose and so on based on the response signal. The measurement module transmits the measured biometric information to the communication terminal in real time or periodically or when the communication terminal requests it.

[0042] Here, the sensor and the measurement module may be manufactured in an integral type, but the sensor and the measurement module may be manufactured to be separable from or couplable to each other. When the sensor and the measurement module are manufactured to be separable from or couplable to each other, the sensor and the measurement module have connection terminals that electrically contact each other, and a response signal generated by the sensor is provided to the measurement module through the connection terminals.

[0043] The communication terminal (30) is a terminal configured to receive biometric information from the biometric information measurement apparatus (10) and output or display the received biometric information to a user, and for example, the biometric information measurement apparatus (10) may be a portable terminal (such as smartphone, tablet PC, or notebook and so on) configured to communicate with the biometric information measurement apparatus (10). However, the communication terminal (30) is not limited thereto, and may be any type of a terminal which has a communication function and program or application can be installed to.

[0044] The biometric information measurement apparatus (10) transmits the biometric information in response to request of the communication terminal (30) or at predetermined times periodically, and for data communication between the biometric information measurement apparatus (10) and the communication terminal (30), the biometric information measurement apparatus (10) and the communication terminal (30) are communicationally connected to each other over a wire by an USB cable and so on or communicationally connected in an wireless communication means such as infrared communication, NFC communication, Bluetooth, etc.

[0045] Here, the biometric information measurement apparatus is attached to a part of the human body by an applicator, and FIG. 2 is a diagram for illustrating an applicator for attaching a biometric information measurement apparatus to a human body according to an embodiment of the present disclosure.

[0046] An application (50) is now described by referring to FIG. 2, the biometric information measurement apparatus (10) is mounted in the applicator (50), and the applicator (50) can be operated so that the biometric information measurement apparatus (10) can be outwardly discharged to the outside of the applicator (50) by the manipulation of the user and then be attached to a specific portion of the human body of the user. The applicator (50) is formed to have a shape that one side of the applicator (50) is open, and the biometric information measurement apparatus (10) is installed to the applicator (50) through the open side of the applicator (50).

[0047] When the biometric information measurement apparatus (10) is attached to a part of the human body using the applicator (50), for inserting an end portion of the sensor included in the biometric information measurement apparatus (10) to skin, the applicator (50) comprises a needle (not shown) formed to cover the end portion of the sensor therein, a first elastic means (not shown) pushing the needle and the end portion of the sensor together towards the skin, and a second elastic means (not shown) configured to retract the needle only. The compressed state of the first elastic means (not shown) arranged to be compressed inside the applicator (50) by the configuration of the applicator (50) can be released, thereby inserting the needle and the end portion of the sensor simultaneously to the skin, and when the end portion of the sensor is inserted to the skin, the compressed state of the second elastic means (not shown) is released, thereby extracting the needle only. By the applicator (50), the user can safely and easily attach the biometric information measurement apparatus (10) to the skin.

[0048] An adhesive tape is provided at a surface of the biometric information measurement apparatus (10) contacting the human body so that the biometric information measurement apparatus (10) can be attached to the skin. Accordingly, if the applicator (50) is moved away from the skin of the human body, the biometric information measurement apparatus (10) is fixedly attached to the skin of the human body by the adhesive tape.

[0049] After that, if the power is supplied to the biometric information measurement apparatus (10), the biometric information measurement apparatus (10) is communicationally connected with the communication terminal (30), and the biometric information measurement apparatus (10) transmits the measured biometric information to the communication terminal (30).

[0050] FIG. 3 is a diagram for illustrating an Randles equivalent circuit of a sensor. As shown in FIG. 3(a), the Randles equivalent circuit is an electric circuit for modeling an electrochemical reaction occurring between a bioelectrode and an electrolyte, that is, an interface of a bodily fluid, and R1(t) is a resistance of the body fluid, C1(t) is a capacitance by an electric double layer, R2(t) is a charge transfer resistance, and W is a Warburg impedance.

[0051] If a film is positioned on the movement path of ions as shown in FIG. 3(b), in the Randles equivalent circuit, the sum of impedances such as resistance, capacitance and so on is a sensor impedance. In a body insertable type sensor, an electrode where an electrochemical reaction occurs is not directly exposed to the sensor, but a diffusion membrane controlling a diffusion rate of a target material and a biocompatible protective layer suppressing a biological immune response has a structure surrounding the sensor. These films can be added in series at a R1(t) position corresponding to a resistance of the body fluid in the Randles circuit. It is common to interpret these films as a parallel structure of a resistor and a capacitor. One of the many cases in which noise is generated by an external force applied to the sensor is changing components of the equivalent circuit shown in FIG. 3.

[0052] In particular, when the components corresponding to R1, R3, R4, and C2 of the equivalent circuit are changed instantaneously, it causes a change in the charging current of the sensor, and the response signal is changed instantaneously.

[0053] Because the biometric information measurement apparatus (10) is attached to the body and biometric information is measured in a state in which the bioelectrode of the sensor is inserted into the body, whenever the user moves, a physical force is applied to the sensor or the body part adjacent to where the sensor is inserted, thereby deforming or moving the sensor, and in this process, impedance components expressed with the equivalent circuit of the sensor are changed by an external force, noise may be included in the response signal generated by the sensor according to the change in the impedance component, and in this way, when the biometric information is measured from the response signal including the noise, the biometric information of the user cannot be accurately measured.

[0054] FIG. 4 is a functional block diagram for illustrating a biometric information measurement apparatus that can reduce the size of noise generated by movement of a sensor according to an embodiment of the present disclosure.

[0055] Describing more in detail with reference to FIG. 4, a bioelectrode is formed in the sensor (100), and the bioelectrode is inserted into the body, thereby causing an oxidation-reduction reaction and generating a response signal. A measurement module (300) provides a measurement power to the bioelectrode of the sensor (100) and measures biometric information based on the response signal received from the bioelectrode of the sensor (100). The measurement module (300) includes a communicator to communicate with the communication terminal, and the measurement module (300) transmits the measured biometric information to the communication terminal in real time, or transmits the measured biometric information to the communication terminal through the communicator when the communication terminal requests.

[0056] The biometric information measurement apparatus according to an embodiment of the present disclosure includes a load unit (200) configured to relatively suppress a noise level applied to the response signal generated by the sensor (100) when the sensor (100) is physically deformed by providing an additional impedance to a sensor impedance of the sensor (100). Here, the magnitude of the additional impedance of the load unit (200) is larger than the magnitude of the sensor impedance of the sensor (100). Preferably, it is characterized in that the load unit (200) is a resistor of 10 KΩ to 10 GΩ.

[0057] Like this, by connecting an additional impedance relatively larger than the sensor impedance to the sensor impedance in addition to the sensor impedance of the sensor (100) using the load unit (200), the effect of the change in the sensor impedance according to the physical change of the sensor (100) becomes relatively low in the overall impedance of the biometric information measurement apparatus, and due to this, even if the physical deformation occurs in the sensor (100), the amount of noise applied to the generated response signal can be reduced.

[0058] As shown in FIG. 5, a working electrode (130) and a counter electrode (150) are formed at one end portion of the sensor, and a load unit 1 (201) is connected only to the working electrode (130) and a separate load is not connected to the counter electrode (150), or a load part 2 (203) is connected only to the counter electrode (150) and a separate load is not connected to the working electrode (130), or the load unit 1 (201) and the load unit 2 (203) are connected to the working electrode (130) and the counter electrode (150), respectively. In this way, even if the load is connected only to the working electrode (130), or the load is connected only to the counter electrode (150), or the loads are connected separately to the working electrode 130 and the counter electrode 150, respectively, an additional impedance relatively larger than a sensor impedance is connected to the sensor impedance in addition to an sensor impedance of the sensor, and, due to this, the effect of the change in the sensor impedance changing according to the physical change of the sensor (100) becomes relatively low in the overall impedance of the biometric information measurement apparatus.

[0059] FIG. 6 is a diagram for explaining an example of a bioelectrode measurement apparatus according to the present disclosure.

[0060] Describing in more detail with respect to FIG. 6, a load unit (200) may be manufactured by being arranged inside a housing of a measurement module (300).

[0061] The sensor (100) includes a flexible base substrate (110), a bioelectrode (130) disposed at one end portion of the base substrate (110), and a conductive tracer (150) formed on an upper surface of the base substrate (110). When the sensor is attached to the body, the bioelectrode (130) disposed at one end portion of the base substrate (110) is inserted into the skin, thereby occurring electrochemical reaction inside the body, and generates a response signal by the electrochemical reaction, and the generated response signal is transmitted along the conductive tracer (150) to a measurement circuit unit (310) of the measurement unit (300). Here, the measurement circuit unit (310) provides a measurement power to the bioelectrode (130) and measures biometric information of the user by receiving a response signal according to an electrochemical reaction from the bioelectrode according to the measurement power, and the measurement circuit unit (310) stores the measured biometric information in an internal memory or transmits the measured biometric information to the communication terminal.

[0062] A load unit (200) is connected to the sensor (100) to provide additional impedance to the sensor impedance of the sensor (100), and therefore, this can contribute to reduce a level of noise generated when a shape of the sensor is deformed or the sensor moves according to a physical load applied to the sensor when a response signal is continuously generated by attaching the sensor to the body. That is, the magnitude of the total impedance in a view of the measurement circuit unit (310) is the sum of the sensor impedance of the sensor (100) and the additional impedance of the load unit (200), and the magnitude of the additional impedance is relatively greater than the magnitude of the sensor impedance. Therefore, even if the sensor impedance is changed due to deformation or movement in or of the sensor, the effect or contribution of the change in the sensor impedance with respect to the overall impedance is small, and accordingly, the amount of noise generated in the response signal generated by the sensor can be reduced.

[0063] FIG. 7 is a diagram for explaining another example of a biometric information measurement apparatus according to the present disclosure.

[0064] Describing in detail with reference to FIG. 7, a load unit (200) may be manufactured as a conductive tracer of the sensor (100).

[0065] A sensor (100) includes a flexible base substrate (110), a bioelectrode (130) disposed at one end portion of the base substrate (110), and a conductive tracer formed on the upper surface of the base substrate (110), and in another example of a biometric information measurement apparatus according to the present disclosure, a conductive trace may be manufactured as the load unit (200) instead of a separate load unit. When the sensor is attached to the body, the bioelectrode (130) disposed on one end portion of the base substrate 110 is inserted into the skin, this causes an electrochemical reaction inside the body, thereby generating a response signal, and the generated response signal is transmitted along the conductive tracer to the measurement circuit unit (310) of the measurement unit (300).

[0066] Typically, a conductive tracer is formed to have an impedance as small as possible, but in another example of a biometric information measurement apparatus according to the present disclosure, a conductive tracer is manufactured to have a relatively high impedance in order to operate the conductive tracer as the load unit (200). Preferably, in order to have a high impedance so that the conductive tracer operates as a load part, the conductive tracer may be manufactured to have a high impedance by varying a material, shape, width, and length of the conductive tracer and so on.

[0067] The load unit (200) provides an additional impedance to the sensor impedance of the sensor (100) in order to contribute to reduce a level of noise generated when a shape of the sensor is deformed or the sensor moves according to a physical load applied to the sensor when a response signal is continuously generated by attaching the sensor to the body. That is, the magnitude of the total impedance in a view of the measurement circuit unit (310) is the sum of the sensor impedance of the sensor (100) and the additional impedance of the load unit (200), and the magnitude of the additional impedance is relatively greater than the magnitude of the sensor impedance. Therefore, even if the sensor impedance is changed due to deformation or movement in or of the sensor, the effect or contribution of the change in the sensor impedance with respect to the overall impedance is small, and accordingly, the amount of noise generated in the response signal generated by the sensor can be reduced.

[0068] FIG. 8 is a diagram for explaining another example of a biometric information measurement apparatus according to the present disclosure.

[0069] Describing in detail with reference to FIG. 8, the sensor (100) and the measurement unit (300) are manufactured independently and are manufactured to be separable from or couplable to each other, and connection terminals (210, 230) for electrically connecting the sensor (100) and the measurement unit (300) when being coupled to each other are formed at the sensor (100) and the measurement unit (300). That is, the first connection terminal (210) is formed at one end of the sensor (100) couplable with the measurement unit (300), and the second connection terminal (230) for electrically connecting the measurement unit (300) with the sensor (100) is formed at the measurement unit (300). A response signal generated from the bioelectrode of the sensor (100) is transmitted to the first connection terminal (210) through the conductive tracer, and the second connection terminal (230) electrically connected to the first connection terminal (210) receives the response signal and transmits it to the measurement circuit unit (310).

[0070] Typically, a connection terminal uses a conductive elastic body with low impedance, but in another example of a biometric information measurement apparatus according to the present disclosure, connection terminals are manufactured to have a relatively high impedance in order to operate connection terminals (210, 230) as the load unit (200). Preferably, in order to have a high impedance so that the connection terminals (210, 230) can operate as a load part, the connection terminals (210, 230) may be manufactured to have a high impedance by varying a material, shape, width, and length of the connection terminals (210, 230) and so on.

[0071] The load unit (200) provides an additional impedance to the sensor impedance of the sensor (100) in order to contribute to reduce a level of noise generated when a shape of the sensor is deformed or the sensor moves according to a physical load applied to the sensor when a response signal is continuously generated by attaching the sensor to the body. That is, the magnitude of the total impedance in a view of the measurement circuit unit (310) is the sum of the sensor impedance of the sensor (100) and the additional impedance of the load unit (200), and the magnitude of the additional impedance is relatively greater than the magnitude of the sensor impedance. Therefore, even if the sensor impedance is changed due to deformation or movement in or of the sensor, the effect or contribution of the change in the sensor impedance with respect to the overall impedance is small, and accordingly, the amount of noise generated in the response signal generated by the sensor can be reduced.

[0072] FIG. 9 is a diagram for explaining another example of a biometric information measurement apparatus according to the present disclosure.

[0073] Describing in detail with reference to FIG. 9, the measurement unit (300) includes a power supplier (310), a current-voltage converter (330), a biometric information generation module (370), and a temperature sensor (390).

[0074] The power supplier (310) applies a measurement power to the sensor, and the current-voltage converter (330) receives an analog current of a response signal from the sensor and converts it into a voltage of a measurement signal. Here, the current-voltage converter (330) may be OPAMP. The biometric information generation module (370) converts the analog measurement signal to digital to generate biometric information. The level of an electrical load of the load unit (200), that is, the level of an additional impedance, is changed according to the temperature of the load unit (200), and the temperature senser (390) measures a temperature of the load unit itself or an ambient temperature around the load unit, and provides information on the measured temperature to the biometric information generation module (370). The biometric information generation module (370) determines the level of the additional impedance in consideration of the temperature of the load unit (200) based on the measured temperature, and the biometric information can be accurately measured from the response signal based on the determined level of the additional impedance.

[0075] The measurement circuit unit described above with reference to FIGS. 5 to 8 includes a power supplier (310), a current-voltage converter (330), a biometric information generation module (370) and a temperature senser (390), and can operate in the same manner.

[0076] Preferably, another example of a biometric information measurement apparatus according to the present disclosure further includes a filter unit (350), and the filter unit (350) filters a measurement signal converted into a voltage with a low-frequency band-pass filter to remove a high-frequency component of noise from the measurement signal.

[0077] That is, a biometric information measurement apparatus according to the present apparatus described with reference to FIG. 9 further includes a filter unit (350), by adding an additional impedance to a sensor impedance through the load unit (200), even if the sensor impedance is changed, the contribution of the change in the sensor impedance becomes small, thereby reducing the level of the noise in a current of a response signal applied to the current-voltage converter (330), and additionally, by removing high-frequency components of the noise from the measurement signal converted through the filter unit (350), the biometric information can be measured more accurately. Furthermore, OPAMP is used as the current-voltage converter (330), the current of the response signal of which the level of the noise is reduced through the load unit (200) is amplified by the current-voltage converter (330) to generate a voltage of the measurement signal, therefore through the combination of the load unit (200) and the filter unit (350), the amplification rate of the current-voltage converter (330) can be increased to reduce the measurement range, and it is possible to accurately measure the biometric information by being less affected by noise than simply using the filter unit (350) alone.

[0078] The present disclosure has been described with reference to embodiments shown in the drawings, but this is only exemplary, and it will be understood by those skilled in the art that various modifications and other equivalent embodiments are possible therefrom. Accordingly, the technical protection scope of the present disclosure should be determined by the technical spirit of the appended claims.