JP7039925B2 - Bioanalyzer - Google Patents

Description

The present invention relates to a technique for processing a signal.

Conventionally, a technique for processing a voltage signal according to the level of light received by a light receiving element has been proposed. For example, Patent Document 1 discloses a technique of removing a DC component from a light receiving signal generated by a light receiving element and then amplifying an AC component. The AC component after amplification is used to calculate the concentration of blood component.

Japanese Unexamined Patent Publication No. 2004-290545

In the technique of Patent Document 1, when the DC component of the received light signal is used for calculating the concentration of the blood component, an element for processing the DC component is required separately from the element for processing the AC component. That is, it is necessary to separate the AC component and the DC component from the received light signal and process each component individually, which causes a problem that the configuration becomes complicated. In consideration of the above circumstances, a preferred embodiment of the present invention simplifies the configuration for amplifying the high frequency component and maintaining the low frequency component among the voltages corresponding to the current generated by the light receiving element. The purpose is to make it.

In order to solve the above problems, the signal processing circuit according to the preferred embodiment of the present invention includes a current / voltage conversion unit that converts the current generated by the light receiving element into a first voltage, and a high frequency range of the first voltage. It is provided with a high frequency amplification unit that amplifies a component and generates a second voltage of the first voltage that maintains a low frequency component without separating the high frequency component and the low frequency component. In the above aspect, the second voltage that amplifies the high frequency component of the first voltage and maintains the low frequency component of the first voltage is generated without separating the high frequency component and the low frequency component. , The second high-frequency component of the first voltage is amplified and the low-frequency component is maintained, as compared with the configuration in which the high-frequency component and the low-frequency component of the first voltage are separated and processed individually. The configuration for generating voltage is simplified.

In a preferred embodiment of the present invention, the high frequency amplification unit includes a first input end to which the first voltage is input, a second input end, an operational amplifier that outputs the second voltage, and the first. Between the first resistance element installed on the feedback path that feeds back the two voltages to the second input end, the second resistance element connected to the second input end, the second resistance element, and the ground wire. Includes a first capacitive element connected to. In the above embodiment, the high frequency component of the first voltage is amplified by a simple configuration in which the first capacitance element is added to the non-inverting amplifier circuit composed of the operational amplifier, the first resistance element, and the second resistance element. It is possible to generate a second voltage that maintains the low frequency component.

In a preferred embodiment of the present invention, the high frequency amplification unit includes a second capacitive element connected in parallel with the first resistance element. In the above embodiment, since the high frequency amplification unit includes the second capacitance element connected in parallel with the first resistance element, the high frequency noise of the second voltage can be reduced by the second capacitance element.

The bioanalyzer according to a preferred embodiment of the present invention includes a light receiving element that receives light coming from a living body, a signal processing circuit of each of the above-described embodiments in which a current generated by the light receiving element is input, and the signal processing circuit. It is provided with a bioanalysis unit that calculates a biometric index related to the living body according to the second voltage generated by. Since the configuration of each of the above-mentioned signal processing circuits for amplifying the high frequency component of the first voltage and generating the second voltage maintaining the low frequency component is simplified, the second voltage is used in the bioanalytical device. Accordingly, the configuration for calculating the biometric index for the living body is also simplified.

In a preferred embodiment of the present invention, the biological index is an index relating to blood flow or blood pressure of the living body. In the above aspect, there is an advantage that an index related to blood flow or blood pressure, which is a basic and important index for diagnosing the condition of a living body, can be calculated.

In a preferred embodiment of the present invention, the bioanalytical unit calculates a value obtained by integrating the product of the intensity of each frequency in the intensity spectrum of the second voltage and the frequency within a predetermined frequency range in the second voltage. The index related to the blood flow is calculated by normalizing with the low frequency component. In the above embodiment, the value obtained by integrating the product of the intensity of each frequency in the intensity spectrum of the second voltage and the frequency within a predetermined frequency range is normalized by the low frequency component of the second voltage and is an index related to blood flow. Is calculated, for example, it is simpler than the configuration in which the value obtained by integrating the product of the intensity of each frequency in the intensity spectrum of the second voltage and the frequency within a predetermined frequency range is calculated as an index related to blood flow. It is possible to calculate the index related to blood flow with the same or higher accuracy in the configuration.

It is a side view of the bioanalysis apparatus which concerns on 1st Embodiment of this invention. It is a block diagram focusing on the function of a bioanalyzer. It is a block diagram of a signal processing circuit. It is a graph which showed the 1st voltage and the 2nd voltage. It is a virtual block diagram which shows the function of the amplification processing part with respect to the high region component of a feedback voltage. It is a virtual block diagram which shows the function of the amplification processing part with respect to the low region component of a feedback voltage. It is a graph which shows the amplification factor characteristic of a high region amplification part. It is a schematic diagram which shows the use example of the bioanalysis apparatus which concerns on 2nd Embodiment. It is a schematic diagram which shows the other use example of the biological analysis apparatus which concerns on 2nd Embodiment. It is a block diagram of the biological analysis apparatus in the modification. It is a block diagram of the biological analysis apparatus in the modification. It is a block diagram of the biological analysis apparatus in the modification.

<First Embodiment>
FIG. 1 is a side view of the bioanalytical apparatus 100 according to the first embodiment of the present invention. The bioanalytical device 100 is a measuring device that non-invasively measures an index related to the blood flow of a subject's living body (hereinafter referred to as “blood flow index”). The bioanalytical device 100 is attached to a specific part (hereinafter referred to as “measurement part”) H in the body of the subject. For example, the wrist and the upper arm are exemplified as the measurement site H.

The bioanalytical device 100 is attached to the measurement site H. As illustrated in FIG. 1, the bioanalytical device 100 of the first embodiment is a wristwatch-type portable device including a housing portion 12 and a belt 14. The bioanalytical device 100 is attached to the body of the subject by winding the belt 14 around the measurement site H.

FIG. 2 is an electrical configuration diagram of the bioanalytical device 100. The bioanalysis device 100 includes a detection device 30, a bioanalysis unit 22, and a display device 23. The bioanalysis unit 22 is installed inside the housing unit 12. As exemplified in FIG. 1, the display device 23 (for example, a liquid crystal display panel) is installed on the surface of the housing portion 12 opposite to the measurement portion H. The display device 23 displays various images including the measurement result.

The detection device 30 is an optical sensor module that generates a detection signal S according to the state of the measurement site H. As illustrated in FIG. 2, the detection device 30 of the first embodiment includes a light emitting element 31, a light receiving element 32, a drive circuit 33, and a signal processing circuit 34. The light emitting element 31 and the light receiving element 32 are installed, for example, in the housing portion 12 at a position facing the measurement portion H. It is also possible to install one or both of the drive circuit 33 and the signal processing circuit 34 as an external circuit separate from the detection device 30.

The light emitting element 31 is a light source that irradiates the measurement site H with light. The light emitting element 31 of the first embodiment irradiates the measurement site H with a coherent laser beam in a narrow band. For example, a VCSEL (Vertical Cavity Surface Emitting LASER) or the like that emits laser light by resonance in a resonator is preferably used as the light emitting element 31. The light emitting element 31 of the first embodiment irradiates the measurement site H with light having a predetermined wavelength λ (λ = 800 nm to 1300 nm) in the near infrared region, for example. The drive circuit 33 causes the light emitting element 31 to emit light. It should be noted that a plurality of light emitting elements 31 that emit light having different wavelengths may be used. Further, the light emitted by the light emitting element 31 is not limited to near-infrared light.

The light incident on the measurement site H from the light emitting element 31 is emitted to the outside of the living body after repeating diffuse reflection while passing through the inside of the measurement site H. Specifically, light that has passed through a blood vessel such as an artery existing inside the measurement site H (for example, a brachial artery, a radial artery, or an ulnar artery) and blood in the blood vessel is emitted from the measurement site H. The light receiving element 32 receives the light arriving from the measurement site H. Specifically, the light receiving element 32 generates a current according to the intensity of the received light. For example, a photodiode (PD: Photo Diode) that generates an electric charge according to the light receiving intensity is used as the light receiving element 32. Specifically, a light receiving element 32 having a photoelectric conversion layer formed of InGaAs (indium gallium arsenide), which exhibits high sensitivity in the near infrared region, is suitable. As can be understood from the above description, the detection device 30 of the first embodiment is a reflection type optical sensor in which the light emitting element 31 and the light receiving element 32 are located on one side of the measurement site H. However, a transmissive optical sensor in which the light emitting element 31 and the light receiving element 32 are located on opposite sides of the measurement site H may be used as the detection device 30.

FIG. 3 is a block diagram of the signal processing circuit 34. The signal processing circuit 34 generates a detection signal S according to the intensity of the light received by the light receiving element 32. Specifically, the signal processing circuit 34 includes a current / voltage conversion unit 341 and a high frequency amplification unit 343.

The current / voltage conversion unit 341 converts the current generated by the light receiving element 32 by receiving light into the first voltage V1. Specifically, the current / voltage conversion unit 341 is a transimpedance amplifier composed of, for example, an operational amplifier 51, a resistance element 53, and a capacitive element 55.

The high frequency amplification unit 343 generates a second voltage V2 from the first voltage V1 generated by the current / voltage conversion unit 341. FIG. 4 is a graph showing a first voltage V1 (solid line) and a second voltage V2 (broken line). As can be seen from FIG. 4, the second voltage V2 is a voltage that amplifies the high frequency component (AC component) of the first voltage V1 and maintains the low frequency component (DC component) of the first voltage V1. .. Specifically, the high frequency amplification unit 343 includes an amplification processing unit 60 and a second capacitance element 80, as illustrated in FIG. The amplification processing unit 60 includes an operational amplifier 61, a first resistance element 63, a second resistance element 65, and a first capacitance element 67.

The operational amplifier 61 includes a first input end (non-inverting input end) T1 and a second input end (inverting input end) T2. The first voltage V1 generated by the current / voltage conversion unit 341 is input to the first input terminal T1. The second voltage V2 generated by the operational amplifier 61 is output from the output terminal Tout. The output end Tout and the second input end T2 of the operational amplifier 61 are connected via the first resistance element 63 (resistance value R1). That is, a feedback path (negative feedback path) for feeding back the second voltage V2 to the second input terminal T2 of the operational amplifier 61 is formed. Specifically, a voltage (hereinafter referred to as “feedback voltage”) Vf corresponding to the second voltage V2 is input to the second input terminal T2 via the feedback path.

The second resistance element 65 (resistance value R2) is connected to the second input terminal T2 of the operational amplifier 61. A first capacitance element 67 (capacitance C1) is connected between the second resistance element 65 and the ground wire. Specifically, one terminal E1 of the first capacitance element 67 is connected to the second resistance element 65, and the other terminal E2 is connected to the ground wire. The first capacitance element 67 of the first embodiment passes a high-frequency component of a current (specifically, a component exceeding the frequency fL) corresponding to the feedback voltage Vf, and a low-frequency component of the current (specifically, a frequency). It functions as a high-pass filter that blocks (components below fL). The frequency fL is expressed by the following mathematical formula (1). It is possible to set the frequency fL according to the resistance value R2 of the second resistance element 65 and the capacitance C1 of the first capacitance element 67.

FIG. 5 is a virtual configuration diagram showing the function of the amplification processing unit 60 for the high frequency component of the feedback voltage Vf, and FIG. 6 is a virtual configuration diagram showing the function of the amplification processing unit 60 for the low frequency component of the feedback voltage Vf. It is a block diagram. As described above, since the high frequency component of the current corresponding to the feedback voltage Vf passes through the first capacitance element 67, the high frequency component is equivalent to the configuration in which the second resistance element 65 is grounded. That is, as illustrated in FIG. 5, for the high frequency component (component exceeding the frequency fL) of the feedback voltage Vf, a non-inverting amplifier circuit (op amp) in which the second resistance element 65 is connected to the second input terminal T2. ), The amplification processing unit 60 functions. Therefore, the high frequency component of the first voltage V1 in FIG. 4 is amplified at a desired amplification factor A. The amplification factor A is expressed by the following mathematical formula (2). The amplification factor A can be set according to the resistance value R1 of the first resistance element 63 and the resistance value R2 of the second resistance element 65.

On the other hand, since the low frequency component of the current corresponding to the feedback voltage Vf is cut off by the first capacitance element 67, the low frequency component is equivalent to the configuration in which the second resistance element 65 is isolated from the ground wire. That is, as illustrated in FIG. 6, for the low frequency component (component below the frequency fL) of the feedback voltage Vf, the amplification process is performed as a voltage follower type buffer circuit in which the amplification factor is set to 0 dB (1 times). The unit 60 functions. Therefore, the low frequency component of the first voltage V1 in FIG. 4 is maintained at the second voltage V2. As can be understood from the above explanation, the high frequency amplification unit 343 amplifies the high frequency component of the first voltage V1 and maintains the low frequency component of the first voltage V1 to obtain the high frequency component. It functions as an element that is generated without separating the low frequency component and the low frequency component.

As illustrated in FIG. 3, the second capacitance element 80 (capacitance C2) is connected in parallel with the first resistance element 63 of the amplification processing unit 60. The second capacitance element 80 functions as a low-pass filter that removes high-frequency noise that may occur in the second voltage V2. Specifically, the component of the output voltage (second voltage V2) of the operational amplifier 61 that is lower than the frequency fH (> fL) is passed, and the component that is higher than the frequency fH is cut off. The frequency fH is expressed by the following mathematical formula (3). It is possible to set the frequency fH according to the resistance value R1 of the first resistance element 63 and the capacitance C2 of the second capacitance element 80.

FIG. 7 is a graph showing the amplification factor characteristics of the high frequency amplification unit 343. As can be seen from FIG. 7, the low frequency component (component below the frequency fL) of the first voltage V1 is maintained, and the high frequency component (component above the frequency fL) of the first voltage V1 has an amplification factor A (1 + R1). It is amplified by / R2). Further, among the high frequency components of the first voltage V1, the components exceeding the frequency fH (that is, the components that can cause high frequency noise) are reduced. The second voltage V2 generated by the high frequency amplification unit 343 is output to the bioanalysis unit 22 as a detection signal S. The illustration of the A / D converter that converts the detection signal S output from the high frequency amplification unit 343 from analog to digital is omitted for convenience.

The light that reaches the light receiving element 32 of FIG. 2 is a component diffusely reflected by a tissue (stationary tissue) that is stationary inside the measurement site H and an object that moves inside the artery inside the measurement site H (typically). Includes components diffusely reflected by red blood cells). The frequency of light does not change before and after diffuse reflection in stationary tissue. On the other hand, before and after diffuse reflection in erythrocytes, the frequency of light changes by the amount of change (hereinafter referred to as "frequency shift amount") proportional to the movement speed (that is, blood flow velocity) of erythrocytes. That is, the light that passes through the measurement portion H and reaches the light receiving element 32 contains a component that fluctuates (frequency shifts) by the frequency shift amount with respect to the frequency of the light emitted by the light emitting element 31. The detection signal S supplied to the bioanalysis unit 22 is an optical beat signal reflecting the frequency shift due to the blood flow inside the measurement site H.

The bioanalysis unit 22 calculates the blood flow index according to the detection signal S (second voltage V2) generated by the signal processing circuit 34. For example, the bioanalysis unit 22 is realized by executing a program by an arithmetic processing unit such as a CPU (Central Processing Unit) or an FPGA (Field-Programmable Gate Array). The biological analysis unit 22 of the first embodiment calculates the blood flow index F (so-called FLOW value) as the blood flow index. The blood flow index F is an index of the blood flow at the measurement site H (that is, the volume of blood moving in the artery within a unit time). Specifically, the bioanalysis unit 22 calculates an intensity spectrum from the detection signal S, and calculates a blood flow index F from the intensity spectrum. The blood flow index F is calculated by the following formula (4a). The symbol <I ² > in the equation (4a) is the average value of the intensity G (0) (that is, the signal intensity of the low frequency component) at 0 Hz in the intensity spectrum. The bioanalysis unit 22 separates the low frequency component from the detection signal S by arithmetic processing, and uses the average value of the signal strength I of the low frequency component for the calculation of the mathematical formula (4a). The blood flow index F may be calculated with the average intensity of the detection signal S over the entire band as <I ² >.

As understood from the equation (4a), the first-order moment (f × G (f)), which is the product of the signal intensity G (f) of each frequency f in the intensity spectrum and the frequency f, is the lower limit on the frequency axis. The blood flow index F is calculated by integrating the range between the value f1 and the upper limit value f2. As understood from the above description, the bioanalysis unit 22 sets the product of the intensity G (f) of each frequency f in the intensity spectrum of the second voltage V2 and the frequency f within a predetermined frequency range (f1 to f2). The value integrated in is normalized by the low frequency component of the second voltage V2 to calculate the blood flow index F. The bioanalysis unit 22 may calculate the blood flow index F by the calculation of the following mathematical formula (4b) in which the integral of the mathematical formula (4a) is replaced with the sum (Σ). The calculation of the blood flow index F by the bioanalysis unit 22 is repeatedly executed every unit period. The display device 23 displays the blood flow index F calculated by the bioanalysis unit 22.

As can be understood from the above description, in the first embodiment, the second voltage V2 that amplifies the high frequency component of the first voltage V1 and maintains the low frequency component of the first voltage V1 is the high frequency component. Since it is generated without separating the low frequency component, it is out of the first voltage V1 as compared with the configuration in which the high frequency component and the low frequency component are separated and processed individually in the first voltage V1. The configuration for generating the second voltage V2 that amplifies the high frequency component and maintains the low frequency component is simplified. As a result, the configuration for calculating the blood flow index F according to the second voltage V2 is also simplified. Since the high frequency component is very weak with respect to the low frequency component at the first voltage V1, the blood flow index F cannot be calculated with high accuracy unless the high frequency component is amplified. In the first embodiment, since the high frequency component is amplified at the second voltage V2 (the high frequency component having a high SN ratio can be obtained), the blood flow index F can be calculated with high accuracy.

In the first embodiment, in particular, the value obtained by integrating the product of the intensity of each frequency in the intensity spectrum of the second voltage V2 and the frequency within a predetermined frequency range is normalized by the low frequency component of the second voltage V2. Since the blood flow index F is calculated, for example, the value obtained by integrating the product of the intensity of each frequency in the intensity spectrum of the second voltage V2 and the frequency within a predetermined frequency range is calculated as the blood flow index F (the relevant). The influence of the variation in the amount of light of the light emitting element 31 and the variation in the amount of ambient light (for example, illumination light or sunlight) is reduced as compared with the configuration in which the numerical value is not normalized). Therefore, the blood flow index F can be calculated with an accuracy equal to or higher than that of the non-normalized configuration with a simple configuration.

<Second Embodiment>
FIG. 8 is a schematic diagram showing a usage example of the bioanalytical apparatus 100 in the second embodiment. As illustrated in FIG. 8, the bioanalytical device 100 includes a detection unit 71 and a display unit 72 that are configured as separate bodies from each other. The detection unit 71 includes the detection device 30 exemplified in each of the above-described embodiments. FIG. 8 illustrates a detection unit 71 in a form worn on the upper arm of a subject. As illustrated in FIG. 9, a detection unit 71 worn on the wrist of the subject is also suitable.

The display unit 72 includes the display device 23 exemplified in each of the above-described embodiments. For example, an information terminal such as a mobile phone or a smartphone is a suitable example of the display unit 72. However, the specific form of the display unit 72 is arbitrary. For example, a wristwatch-type information terminal that can be carried by the subject, or a dedicated information terminal of the bioanalytical device 100 may be used as the display unit 72.

The bioanalysis unit 22 is mounted on the display unit 72, for example. The detection signal S generated by the detection device 30 of the detection unit 71 is transmitted to the display unit 72 by wire or wirelessly. The bioanalysis unit 22 of the display unit 72 calculates the blood flow index F from the detection signal S and displays it on the display device 23.

The bioanalysis unit 22 may be mounted on the detection unit 71. The bioanalysis unit 22 calculates the blood flow index F from the detection signal S generated by the detection device 30, and transmits data for displaying the blood flow index F to the display unit 72 by wire or wirelessly. The display device 23 of the display unit 72 displays the blood flow index F indicated by the data received from the detection unit 71.

<Modification example>
Each of the above-exemplified forms can be variously modified. Specific modes of modification are illustrated below. It is also possible to appropriately merge two or more embodiments arbitrarily selected from the following examples.

(1) In each of the above-described embodiments, the high-frequency amplification unit 343 is configured by the amplification processing unit 60 and the second capacitance element 80, but the configuration of the high-frequency amplification unit 343 is not limited to the above examples. For example, the high frequency amplification unit 343 may be configured only by the amplification processing unit 60. That is, the second capacitance element 80 is not indispensable in the high frequency amplification unit 343. However, according to the configuration in which the high frequency amplification unit 343 includes the second capacitance element 80, the high frequency noise of the second voltage V2 can be reduced by the second capacitance element 80. Further, instead of the second capacitance element 80, a low-pass filter capable of reducing high-frequency noise in the second voltage V2 may be installed after the output terminal Tout.

(2) In each of the above-described embodiments, the amplification processing unit 60 is composed of the operational amplifier 61, the first resistance element 63, the second resistance element 65, and the first capacitance element 67, but the configuration of the amplification processing unit 60 is as described above. It is not limited to the example of. However, according to each of the above-described embodiments in which the amplifier processing unit 60 is composed of the operational amplifier 61, the first resistance element 63, the second resistance element 65, and the first capacitance element 67, the operational amplifier 61 and the first resistance element 63 A second component of the first voltage V1 that amplifies the high frequency component and maintains the low frequency component by a simple configuration in which the first capacitance element 67 is added to the non-inverting amplifier circuit composed of the second resistance element 65 and the second resistance element 65. The voltage V2 can be generated.

(3) In each of the above-described embodiments, the bioanalysis unit 22 calculates the blood flow index F as the blood flow index, but the blood flow index calculated by the bioanalysis unit 22 is not limited to the above examples. For example, it is also possible to calculate the blood flow according to the blood flow index F or the blood flow velocity obtained by dividing the blood flow by the cross-sectional area of the blood vessel as the blood flow index. Further, the index calculated by the bioanalysis unit 22 is not limited to the blood flow index. For example, the blood volume index (so-called MASS value), the blood vessel diameter and the cross-sectional area of the blood vessel according to the blood volume index, the oxygen saturation (SpO2), or the index related to the blood pressure of the living body (for example, blood pressure, average blood pressure or pulse pressure) is used as the living body. The analysis unit 22 may calculate. Each index exemplified above is comprehensively expressed as an index related to a living body (hereinafter referred to as "biological index"). The bio-analysis unit 22 functions as an element for calculating a bio-index according to the second voltage V2. From the biometric index (for example, blood pressure) calculated by the bioanalysis unit 22, the state of the subject (for example, blood pressure state) is specified from a plurality of stages (for example, abnormal / high / normal, etc.) and notified to the subject. Is also possible.

(4) In each of the above-described embodiments, the bioanalytical device 100 configured as a single device is exemplified, but as shown in the following examples, a plurality of elements of the bioanalytical device 100 can be realized as devices that are separate from each other. ..

In each of the above-described embodiments, the bioanalytical device 100 including the detection device 30 is illustrated, but as illustrated in FIG. 10, a configuration in which the detection device 30 is separate from the bioanalysis device 100 is also assumed. The detection device 30 is a portable optical sensor module mounted on the measurement site H such as the wrist or upper arm of the subject. The bioanalysis device 100 is realized by an information terminal such as a mobile phone or a smartphone. The bioanalytical device 100 may be realized by a wristwatch type information terminal. The detection signal S generated by the detection device 30 is transmitted to the bioanalysis device 100 by wire or wirelessly. The bioanalysis unit 22 of the bioanalysis device 100 calculates a biometric index from the detection signal S and displays it on the display device 23. As understood from the above description, the detection device 30 may be omitted from the bioanalysis device 100.

In each of the above-described embodiments, the bioanalytical device 100 including the display device 23 is illustrated, but as illustrated in FIG. 11, a configuration in which the display device 23 is separate from the bioanalysis device 100 is also assumed. The bioanalysis unit 22 of the bioanalysis device 100 calculates a bioindex from the detection signal S, and transmits data for displaying the index to the display device 23. The display device 23 may be a dedicated display device, but may be mounted on, for example, an information terminal such as a mobile phone or a smartphone, or a wristwatch-type information terminal that can be carried by a subject. The biometric index calculated by the bioanalytical unit 22 of the bioanalyzing device 100 is transmitted to the display device 23 by wire or wirelessly. The display device 23 displays the biometric index received from the bioanalytical device 100. As understood from the above description, the display device 23 may be omitted from the bioanalytical device 100.

As illustrated in FIG. 12, it is assumed that the detection device 30 and the display device 23 are separate from the bioanalysis device 100 (bioanalysis unit). For example, the bioanalysis device 100 (bioanalysis unit) is mounted on an information terminal such as a mobile phone or a smartphone.

In addition, in the configuration in which the detection device 30 and the bioanalysis device 100 are separated, it is also possible to mount an element for calculating the intensity spectrum on the detection device 30. The intensity spectrum calculated by the detection device 30 is transmitted to the bioanalysis device 100 by wire or wirelessly.

(5) In each of the above-described embodiments, the wristwatch-type bioanalytical device 100 including the housing portion 12 and the belt 14 is exemplified, but the specific form of the bioanalytical device 100 is arbitrary. For example, a patch type that can be attached to the subject's body, an ear-mounted type that can be attached to the subject's ear, a finger-mounted type that can be attached to the subject's fingertips (for example, a nail-attached type), or a subject's head that can be attached. Any form of bioanalytical device 100, such as a head-mounted type, can be adopted.

(6) In each of the above-described embodiments, the biometric index of the subject is displayed on the display device 23, but the configuration for notifying the subject of the biometric index is not limited to the above examples. For example, it is also possible to notify the subject of the biometric index by voice. In the ear-worn bioanalytical apparatus 100 that can be worn on the selvage of the subject, a configuration in which the biometric index is notified by voice is particularly suitable. In addition, it is not essential to notify the subject of the biometric index. For example, the biometric index calculated by the bioanalytical device 100 may be transmitted from the communication network to another communication device. Further, the biometric index may be stored in a storage device (not shown) of the bioanalytical device 100 or a portable recording medium that can be attached to and detached from the bioanalytical device 100.

(7) As described above, the bioanalytical device 100 according to each of the above-mentioned embodiments is realized by the cooperation between the arithmetic processing unit such as a CPU and the program. The program according to a preferred embodiment of the present invention may be provided and installed in a computer in a form stored in a computer-readable recording medium. It is also possible to provide a program stored in a recording medium included in a distribution server to a computer in the form of distribution via a communication network. The recording medium is, for example, a non-transitory recording medium, and an optical recording medium (optical disc) such as a CD-ROM is a good example, but a semiconductor recording medium, a magnetic recording medium, or the like is known as arbitrary. It may include a recording medium in the form of. The non-transient recording medium includes any recording medium other than the transient propagation signal (transitory, propagating signal), and does not exclude the volatile recording medium.

100 ... bioanalytical device, 12 ... housing, 14 ... belt, 22 ... bioanalytical unit, 23 ... display device, 30 ... detection device, 31 ... light emitting element, 32 ... light receiving element, 33 ... drive circuit, 34 ... signal Processing circuit, 341 ... Voltage conversion unit, 343 ... High frequency amplification unit, 51 ... Arithmetic amplifier, 53 ... Resistance element, 55 ... Capacitive element, 60 ... Amplification processing unit, 61 ... Arithmetic amplifier, 63 ... First resistance element, 65 ... second resistance element, 67 ... first capacitance element, 80 ... second capacitance element.

Claims (2)

A light receiving element that receives light coming from a living body,
A current / voltage converter that converts the current generated by the light receiving element into a first voltage, and a second voltage that amplifies the high frequency component of the first voltage and maintains the low frequency component of the first voltage. A signal processing circuit including a high-frequency amplification unit that generates the high-frequency component and the low-frequency component without separating them .
The value obtained by integrating the product of the intensity of each frequency in the intensity spectrum of the second voltage generated by the signal processing circuit and the frequency within a predetermined frequency range is normalized by the low frequency component of the second voltage. It is equipped with a bioanalysis unit that calculates biometric indicators related to the blood flow of the living body.
The high frequency amplification unit is
An operational amplifier that includes a first input end to which the first voltage is input and a second input end and outputs the second voltage.
A first resistance element installed on a feedback path that feeds back the second voltage to the second input end, and
The second resistance element connected to the second input end and
Includes a first capacitive element connected between the second resistance element and the ground wire.
Bioanalyzer. The bioanalytical device according to claim 1 , wherein the high frequency amplification unit includes a second capacitance element connected in parallel with the first resistance element.

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