Biosignal measurement device, biosignal measurement system

Abstract

The present invention enables suppression of motion artifacts by enabling attachment to a position with less movement, reducing the mass to suppress the effect of an acceleration rate, and enabling attachment to the optimal position even when there is an individual difference. The present invention has: a stress transferring part that has a cavity directly above an optical transmitting / receiving part and transfers, to the optical transmitting / receiving part, the stress applied from the outside to the bottom surface of the cavity; a communication part that transmits a signal received from the optical receiver to another communication part; a power supplying part that supplies power to the optical transmitting / receiving part and the communication part; and an outer shell structure that holds the optical transmitting / receiving part, the communication part, and the power supplying part therein and transfers the stress to the living body surface together with the optical transmitting / receiving part.

Description

Technical Field

[0001] The present invention relates to biometric signal measurement that is robust against fluctuations in measurement signals caused by motion artifacts (MA), that is, the movement of a living body, and particularly to a biometric signal measurement device and a biometric measurement system using light.

Background Art

[0002] Conventionally, oximeters and heart rate monitors that are attached to a finger or earlobe with a clip and used are widely used, but they can only be used during rest. Wristwatch-type heart rate monitors are also widespread, but there are problems such as showing a heart rate different from the actual one during exercise or becoming a missing value and not being displayed.

[0003] On the other hand, as an example considering portability, Patent Document 1 has an example of an oximeter and a pressure gauge that measure the temporal lobe in the shape of goggles. The oximeter and the pressure gauge are arranged in a waterproof housing. The position can be adjusted by setting the waterproof housing on a belt and sliding it, but the housing extending from the belt has a large weight and a cantilever structure and is vulnerable to vibration.

[0004] Patent Document 2 has an example of a mask-shaped respiratory interface for a nasal cavity and mouth of a patient. It is inserted into the nostrils and mouth for use. An emitter and a detector of a light sensor are provided in the upper lip portion of the interface device. This also has a large housing and has a drawback of vibrating when moving.

[0005] Non-Patent Document 1 has an example of an ear-mounted sensor. A PPG (Photoplethysmography) sensor is attached to the earlobe. The magnetic force of a neodymium magnet is used to fix it to the earlobe. It also has an acceleration sensor used to suppress MA (Motion Artifact). The magnet itself acts as a weight and has a drawback of vibrating like a swing at the earlobe.

[0006] Patent Document 3 provides an example of a nasal-mounted PPG sensor. It is used by being fixed to the nasal ala with a clip. However, the nasal ala itself has the problem of expanding and contracting with breathing and talking, and it is a thin, movable part that is easily displaced and vibrated by the weight of the sensor and wires.

[0007] Non-patent document 2 provides an example of a photoplethysmograph worn on the upper arm. It uses a nylon band with an air pad underneath, and the photoplethysmograph is mounted below the air pad. Motion artifacts (MA) are reduced by controlling the pressure of the air pad. However, this method has the drawback of being a large and cumbersome device. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] U.S. Patent Application Publication No. 2019 / 0365302 [Patent Document 2] U.S. Patent Application Publication No. 2014 / 0094669 [Patent Document 3] U.S. Patent Application Publication No. 2014 / 0005557 [Non-patent literature]

[0009] [Non-Patent Document 1] IEEE Transactions on Information Technology in Biomedicine, (USA), 2010, Vol. 14, No. 3, p. 786-794 [Non-Patent Document 2] Masaki Sekine, et al., "Research on the Removal of Motion Artifacts Superimposed on Photoplethysmography Signals," Descente Sports Science, Descente Sports Science Promotion Foundation, June 6, 2014, Vol. 35, No. 6, pp. 123-130. [Overview of the project] [Problems that the invention aims to solve]

[0010] The problem we are trying to solve is that conventional technologies either do not address motion artifacts (MA), or even if they do, they have the following problems.

[0011] Firstly, there is the issue of placement. If attached to areas with vigorous movement, such as the limbs, the sensor will move away from the skin and alter the light path of the PPG. Even on the head, where movement is minimal, movable parts such as the earlobes and nasal wings must be avoided. There also needs to be a sufficient amount of blood flow near the skin surface, which serves as a signal for the PPG.

[0012] Secondly, there is the issue of the sensor's mass. The movement of the living body causes acceleration in the sensor. This acceleration, when multiplied by the mass, becomes stress, which creates a force that tries to separate the sensor from the skin.

[0013] Thirdly, there is the issue of individual differences in the size of living organisms and the position and shape of various body parts. Even with individual differences, it is necessary to detect sufficient biological signals and attach the device while suppressing MA (mechanical amplification). [Means for solving the problem]

[0014] A biosignal measuring device to be attached to the surface of a living body, characterized by comprising: an optical transmitting / receiving unit consisting of at least one pair of optical transmitters and optical receivers arranged on the surface of the living body; a stress transmission unit having a cavity located directly above the optical transmitting / receiving unit and transmitting stress applied from the outside to the bottom surface of the cavity to the optical transmitting / receiving unit; a communication unit that transmits received signals from the optical receiver to another communication unit; a power supply unit that supplies power to the optical transmitting / receiving unit and the communication unit; and an outer shell structure that holds the optical transmitting / receiving unit, the communication unit and the power supply unit internally and transmits the stress to the surface of the living body together with the optical transmitting / receiving unit.

[0015] A biosignal measuring device characterized in that the outer shell structure is made of an elastic material that can be deformed by forces from a living organism, and at least the portion that comes into contact with the living organism's surface is made of a material mainly composed of silicon.

[0016] A biosignal measurement device further comprising a first external structure that generates stress applied to the bottom surface of the cavity.

[0017] A biological signal measurement device, characterized in that, instead of the power supply unit, a power supply unit is provided outside the outer shell structure, and power is supplied to the optical transmission / reception and the communication unit inside the outer shell structure through a detachable connector unit.

[0018] A biological signal measurement device, further comprising a second external structure having power supply wiring and acting stressfully on the stress transmission unit, wherein the power supply wiring is connected to the power supply unit and supplies power to the optical transmission / reception and the communication unit inside the outer shell structure through the connector unit.

[0019] A biological signal measurement device to be worn on the biological surface of the back of the ear or the tip of the nose, comprising an optical transmission / reception unit consisting of at least one set of optical transmitters and optical receivers arranged on a first surface of the biological surface; a communication unit for transmitting a reception signal from the optical receiver to another communication unit; a power supply unit for supplying power to the optical transmission / reception unit and the communication unit; and an outer shell structure for holding the optical transmission / reception unit, the communication unit, and the power supply unit inside, wherein the outer shell structure supports a horizontal vector of stress acting on the optical transmission / reception unit on a second surface different from the first surface and transmits a vertical vector to the first surface.

[0020] The outer shell structure is made of an elastic material that can be deformed by a force from a living body, and at least a portion contacting the biological surface is made of a material mainly composed of silicon.

[0021] A biological signal measurement device, characterized in that the optical transmission / reception unit is arranged on the first surface and the power supply unit is arranged above the second surface.

[0022] A biological signal measurement device, comprising: an optical transceiver unit composed of at least one set of optical transmitters and optical receivers arranged on a biological surface; a communication unit that transmits a received signal from the optical receiver to another communication unit; a power supply unit that supplies power to the optical transceiver unit and the communication unit; and an outer shell structure that holds the optical transceiver unit, the communication unit, and the power supply unit, and includes at least one of the following (1) to (3) as means for transmitting external stress. (1) Means having a cavity for transmitting external stress to the optical transceiver unit. (2) Means for transmitting the vertical vector of the stress acting on the optical transceiver unit to the first surface on which the optical transceiver unit is arranged and supporting the horizontal vector on a second surface different from the first surface. (3) Means for transmitting stress to three surfaces of the back of the ear surface, the root of the ear surface, and the temporal surface.

[0023] The biological signal measurement device according to (3) above, further comprising a third external structure for generating stress applied to at least one of the three surfaces.

[0024] The biological signal measurement device, characterized in that glasses or a mask is used as the third external structure.

[0025] A biological signal measurement device to be worn on the biological surface of a region surrounded by the back of the ear and the temporal region, comprising: an optical transceiver unit composed of at least one set of optical transmitters and optical receivers arranged on the first surface of the biological surface; a communication unit that transmits a received signal from the optical receiver to another communication unit; a power supply unit that supplies power to the optical transceiver unit and the communication unit; and an outer shell structure that holds the optical transceiver unit, the communication unit, and the power supply unit, wherein the outer shell structure transmits stress to three surfaces of the back of the ear surface, the root of the ear surface, and the temporal surface.

[0026] An elastic body made of an elastic material is arranged around the optical transceiver unit, and the optical transceiver unit contacts the skin through the elastic body.

[0027] The biological signal measurement device further comprises a third external structure for generating stress applied to at least one of the three surfaces.

[0028] A biosignal measuring device characterized in that, as the third external structure, eyeglasses or a mask are used, and the device is worn in a position where the light emission of the light transmitter from the area surrounded by the back of the ear and the side of the head can be confirmed from the front of the wearer. [Effects of the Invention]

[0029] The biosignal measurement device and biosignal measurement system of the present invention have the advantage of preventing motion artifacts (MA). [Brief explanation of the drawing]

[0030] [Figure 1] This is a block diagram of the first embodiment of a biosignal measurement device. [Figure 2] This is a block diagram of Embodiment 1 relating to the first embodiment. [Figure 3] This is a diagram illustrating the configuration of Embodiment 1 related to the first embodiment. [Figure 4] This is an external view of Embodiment 1 relating to the first embodiment. [Figure 5] This is an overhead view of Embodiment 1 relating to the first embodiment. [Figure 6] This is a diagram showing the configuration of Embodiment 2 related to the first embodiment. [Figure 7] This is an overhead view of Embodiment 2 relating to the first embodiment. [Figure 8] This is a diagram showing the configuration of Embodiment 3 related to the first embodiment. [Figure 9] This is an overhead view of Embodiment 3 relating to the first embodiment. [Figure 10] This is an overhead view of Embodiment 4 relating to the first embodiment. [Figure 11] This is a diagram showing the configuration of Embodiment 5 related to the first embodiment. [Figure 12] This is a diagram showing the configuration of Embodiment 5 related to the first embodiment. [Figure 13] This is an overhead view of Embodiment 5 relating to the first embodiment. [Figure 14]This is an overhead view of Embodiment 6 relating to the first embodiment. [Figure 15] This is a configuration diagram of Embodiment 6 relating to the first embodiment. [Figure 16] This is an overhead view (a) of Embodiment 6 relating to the first embodiment. [Figure 17] This is an overhead view (b) of Embodiment 6 relating to the first embodiment. [Figure 18] This is a diagram illustrating the configuration of Embodiment 7 related to the first embodiment. [Figure 19] This is an external view of Embodiment 7 relating to the first embodiment. [Figure 20] This is an overhead view of Embodiment 7 relating to the first embodiment. [Figure 21] This is a diagram illustrating the configuration of a second embodiment of the biosignal measurement device. [Figure 22] This figure shows the effect of stress in the second embodiment. [Figure 23] This is an outline view of Embodiment 8 relating to the second embodiment. [Figure 24] This is an overhead view of Embodiment 8 relating to the second embodiment. [Figure 25] This is a diagram illustrating the configuration of a third embodiment of the biosignal measurement device. [Figure 26] This figure shows how stress acts in the third embodiment. [Figure 27] This is an outline view of Embodiment 9 relating to the third embodiment. [Figure 28] This is an overhead view of Embodiment 9 relating to the third embodiment. [Figure 29] This is an overhead view of Embodiment 10 relating to the third embodiment. [Figure 30] This is a block diagram of the optical transceiver unit. [Figure 31] This is a block diagram of the communications department. [Figure 32] This is a block diagram of the power supply unit. [Figure 33] This is a block diagram of the fourth embodiment of the biosignal measurement device. [Figure 34]This is a block diagram of the fourth embodiment of the biosignal measurement system. [Figure 35] This is a block diagram of the fourth embodiment of the biosignal measurement system. [Figure 36] This is a block diagram of the fourth embodiment of the biosignal measurement system. [Figure 37] This is a block diagram of the time synchronization block. [Figure 38] This is a block diagram of the preprocessing block. [Figure 39] This is a block diagram of the post-processing block. [Figure 40] This is a block diagram of an abstract block. [Figure 41] This is a block diagram of the system reconfiguration block. [Figure 42] This is a block diagram of the user interface (UI) blocks. [Figure 43] Examples of acquisition from various parts of the body (fingers, wrists, earlobes, nose) are shown. [Figure 44] Examples of acquisition from various parts of the body (various parts of the face) are shown. [Figure 45] Examples of acquisition from various parts of the body (various parts of the foot) are shown. [Figure 46] This is a configuration diagram of Example 12 relating to the fifth embodiment of the biosignal measurement device. [Figure 47] This is a diagram showing the configuration of Embodiment 13, relating to the fifth embodiment. [Figure 48] This is an example of the configuration around the optical transmitting / receiving unit and the stress transmission unit. [Figure 49] This is a diagram showing the configuration of Embodiment 14, relating to the fifth embodiment. [Figure 50] This is a diagram showing the configuration of Embodiment 15, relating to the fifth embodiment. [Figure 51] This is a block diagram of Embodiment 15 relating to the fifth embodiment. [Figure 52] This is a block diagram of Embodiment 16 relating to the fourth embodiment. [Figure 53] This is a detailed block diagram of Embodiment 16 relating to the fourth embodiment. [Figure 54]This is a block diagram of Embodiment 17 relating to the fourth embodiment. [Figure 55] This is a block diagram of the phase adjustment block. [Figure 56] This is a block diagram of Embodiment 18 relating to the fourth embodiment. [Figure 57] This is a block diagram of Embodiment 19 relating to the fourth embodiment. [Modes for carrying out the invention]

[0031] (First Embodiment) Figure 1 is a block diagram of the first embodiment of the biosignal measurement device of the present invention. An optical transceiver unit 101, a stress transmission unit 102, a communication unit 103, and a power supply unit 104 are arranged on the body, and these constitute the biosignal measurement device 100.

[0032] The optical transceiver unit 101 is located on the surface of the living body and has the function of transmitting light toward the living body and receiving optical signals that have passed through the living body. The stress transmission unit 102 is positioned directly above the optical transceiver unit 101 and has the function of applying external stress to the living body via the optical transceiver unit 101. The communication unit 103 has the function of transmitting the optical signal received by the optical transceiver unit 101 to another communication unit. The power supply unit 104 has the function of supplying power to the optical transceiver unit 101 and the communication unit 103.

[0033] By transmitting stress from the stress transmission unit 102 to the optical transmitting / receiving unit 101 from directly above, external stress can be applied to the minimum mass around the optical transmitting / receiving unit 101, thereby minimizing the effects of acceleration on that mass. The communication unit 103 and power supply unit 104 do not necessarily need to be mechanically coupled to the stress transmission unit 102 and the optical transmitting / receiving unit 101; they can be placed in any position as long as they are electrically connected. [Examples]

[0034] Figure 2 is a block diagram of Embodiment 1 relating to the first embodiment of the present invention. It further includes an outer shell structure 201 compared to Figure 1. The outer shell structure 201 can cover, for example, the sides of the optical transmitting / receiving unit 101, as well as the stress transmission unit 102, the communication unit 103, and the power supply unit 104. Each part can be protected mechanically, electrically, and environmentally, such as from moisture. When the mass impact of the power supply unit is small and there is a high benefit to integrating it, such as wanting to make it compact, the power supply unit and other components can also be covered.

[0035] The outer shell structure 201 may be in contact with the skin together with the optical transmitting / receiving unit 101 and transmit stress from the stress transmission unit 102 to the skin. Light transmitted subcutaneously is scattered and spread by the subcutaneous tissue. In some cases, signals from blood flow in an area slightly away from directly below the optical transmitting / receiving unit 101 can be utilized. The outer shell structure 201 can amplify signals from blood flow by applying stress not only to the area directly below the optical transmitting / receiving unit 101 but also to the surrounding area.

[0036] The outer shell structure 201 may be integrally formed with the stress transmission section 102. In other words, the outer shell structure 201 may have the function of the stress transmission section 102 (or the stress transmission section 102 may have the function of the outer shell structure 201).

[0037] Figure 3 shows an example configuration of Embodiment 1. The stress transmission section 102 has a cavity 102a, and the external structure 301 penetrates the cavity 102a. The external structure 301 applies stress 302 to the bottom surface of the cavity 102a (here, a force acting on a surface is replaced by a single arrow). The stress 302 is transmitted from the bottom surface of the cavity 102a to the optical transmitting / receiving section 101, pressing the optical transmitting / receiving section 101 and the outer shell structure 201 against the skin. A reaction force 303 acts from the skin, fixing the optical transmitting / receiving section 101 and the outer shell structure 201 to the skin.

[0038] Stress acts on subcutaneous capillaries, increasing the optical signal. The stress is preferably set to approximately 20-40 mmHg, which is the average blood pressure of the capillaries. Experiments by the inventors have shown that, although varying by location, applying appropriate stress results in an optical signal amplitude more than twice that of the absence of stress. Applying too much stress will cause the signal to drop below this peak.

[0039] Due to the frictional force between the optical transceiver unit 101 and the outer shell structure 201 and the skin, the optical transceiver unit 101 and the outer shell structure 201 remain fixed without displacement even when there is horizontal acceleration. The limit at which displacement does not occur depends on the magnitude of the stress 302 and the coefficient of static friction between the optical transceiver unit 101 and the outer shell structure 201 and the skin.

[0040] Figure 4 is an outline view of Embodiment 1. The stress transmission section 102 and the outer shell structure 201 are integrally formed (hereinafter referred to as the stress transmission section 102), and the black-filled portion is the stress transmission section 102. The optical transmitting / receiving section 101 is in contact with the skin, and for the reasons mentioned above, it is preferable that the stress transmission section 102 surrounding it also be in contact with the skin.

[0041] The stress transmission section 102 can have a protrusion 102b. This is to make effective use of the limited stress applied to the living body. The aforementioned 20-40 mmHg is per unit area, and the load increases as the area increases. Since the living body's pain receptors also react significantly, the area is kept to the minimum necessary. When utilizing the stress of existing biomedical devices, the load that the device can generate is often limited.

[0042] By placing the cavity 102a directly above the optical transceiver unit 101, stress can be applied perpendicularly and directly to the optical transceiver unit 101 and the surrounding protrusions 102b. The communication unit 103 and power supply unit 104 are located above the cavity 102a. By creating a three-story structure with the optical transceiver unit 101 on the first floor, the cavity 102a on the second floor, and the communication unit 103 and power supply unit 104 on the third floor, the volume and footprint of the device 100 can be made smaller and more compact. The power supply unit 104 has a certain volume because it contains batteries, etc., and by placing it on the third floor, the contact area of ​​the protrusions 102b on the first floor with the skin can be optimized. The same can be said for the communication unit 103, which may include antennas and shields related to communication.

[0043] Figure 5 is an overhead view of Embodiment 1. The external structure 301 passes through the cavity 102a of the biosignal measurement device 100. Eyeglasses are used as the external structure 301. The biomeasurement processing device 100 looks different from the outline view in Figure 4, but for example, the one in Figure 4 can be used.

[0044] The eyeglasses 301 have parts called the temple tips 501, temple arms 502, and hinges 503. The part from the temple tips to the temple arms is the part that contacts the temporal lobe. When eyeglasses 301 are worn, a stress 302 is generated toward the temporal lobe. The temple tips 501 and temple arms 502 are beam structures made of elastic material, and a load is generated by their deflection. The value obtained by dividing this load by the contact area is the stress 302.

[0045] The relationship between deflection δ and load W is expressed by Equation 1, where L is the length of the beam, E is Young's modulus, and I is the second moment of area. While a stress simulation of the entire eyeglass frame is necessary for accuracy, roughly speaking, the relationship between deflection δ and load W at a distance L from the hinge 503 can be determined from Equation 1.

[0046]

number

[0047] When wearing glasses, the temple tips come into contact with the temporal lobe, causing a deflection of a few millimeters δ, which generates a load W determined by equation 1. This load W varies depending on the length L from the temple 503 to the point of contact, but is approximately 10 to 20 gf.

[0048] The optical transceiver 101 is positioned on the temporal lobe side of the eyeglasses 301. To obtain the aforementioned stress of 20 to 40 mmHg (27 to 54 gf / cm²) using a load of 10 to 20 gf, it is preferable to set the contact area to 0.19 to 0.74 square centimeters, or approximately 4 to 9 mm square. When increasing the load using a belt, as will be described later for sports applications, the contact area can be further increased. The area of ​​the protrusion 102b in Figure 4 can be set to match this contact area.

[0049] The head is a part of the body that moves relatively little in daily activities, including work and exercise, compared to the limbs, and this allows for the suppression of the frequency of motion artifacts (MA) and the amplitude of fluctuations in optical signals caused by MA. In particular, when measuring the hands and arms, even a slight change in position relative to the heart can cause several times the amplitude change. This phenomenon is less likely to occur in the head. Even in the head, soft parts with a certain length, such as the earlobe, especially when mass such as sensors is added, can cause pendulum-like vibrations, which is unfavorable for MA suppression. Measuring the less mobile parts of the head, such as the temporal region mentioned above, is effective for MA suppression. When a living organism walks in a straight line, there is usually an acceleration of approximately 0.2G in the direction of movement and approximately 0.1G in the lateral direction. The temporal region, which is in the lateral direction, has the smallest acceleration among the parts of the head.

[0050] Reducing the mass of the sensor, including the housing that encloses it, reduces the load on that mass when acceleration is applied. As mentioned above, applying stress to the biological surface has the effect of doubling or more the amplitude of the optical signal. This is because the amplitude changes when the stress changes, which is a factor in MA. For example, if a large housing like those found in conventional technology is used, assuming the mass of the housing is 50g, a force of 5gf acts when the acceleration during walking is 0.1G. This force changes the load of 10 to 20gf by several tens of percent, and it is calculated that the optical signal will also change by an even larger percentage. By adopting a compact structure including the housing, such as a three-story structure as in this embodiment, it is possible to reduce the mass to, for example, a few grams, and the above effect can be suppressed to about 1 / 10.

[0051] As shown in Figure 4, the cavity 102a allows the biosignal measurement device 100 to be positioned at any location on the temple 502 of the eyeglasses 301, from the temple tip 501 to the temple 502, as shown in Figure 5. Head size, ear position, and the location of capillary density vary from person to person. Since the size of the eyeglasses used also varies, being able to move the device to any position is effective in obtaining a large optical signal amplitude. If the optical signal is smaller than a predetermined value, the user or administrator can be notified and the mounting position can be adjusted. MA, or fluctuations in the optical signal due to biological movement (noise), can also be increased by interference with hair or an unstable mounting position. If the noise due to MA is greater than a predetermined value, the user or administrator can be notified and the mounting position can be adjusted in the same way.

[0052] Regarding the contact between the cavity 102a and the eyeglasses 301, the stress transmission part 102 can be made of an elastic material, giving it both the ability to move and the ability to be fixed. This mechanism is such that the cavity 102a is fixed by the force of contraction and friction, and can move when a force greater than the friction is applied. Furthermore, it is preferable to use a biocompatible material for the part that comes into contact with the living body. In this sense, the stress transmission part 102 can be made of a material mainly composed of silicon. In addition, elastic materials have the effect of preventing stress from concentrating in a specific location.

[0053] The optical transmitting / receiving unit 101 can have an optical transmitter and an optical receiver. The light transmitted and received by the optical transmitter and receiver can be any electromagnetic wave that can be selected. The transmittance of living organisms differs depending on the frequency of the electromagnetic wave. Furthermore, there are frequencies that are easier to miniaturize when miniaturizing the device. There is a wavelength range from green visible light to near-infrared light that easily penetrates living organisms, and this range can be utilized.

[0054] Multiple light sources can be used as the light transmitter. LEDs (Light Emitting Diodes) and lasers can be used as light transmitters. For example, by using green, red, near-infrared light in the 900nm range, and near-infrared light in the 1100nm range, absorption in living organisms at different wavelengths can be measured. While LED and laser emission has a steep spectrum, the wavelength can be shifted by changing the temperature of the light transmitter.

[0055] Photodiodes can be used as optical receivers. Photodiodes made of silicon semiconductors are sensitive to a wide range of wavelengths from visible light to near-infrared light. Photodiodes made of InGaAs semiconductors, which are sensitive to longer wavelengths in the near-infrared range, can also be used. Multiple types of photodiodes, each sensitive to different wavelength bands, can also be used. Optical filters can be placed in front of the photodiode to provide greater selectivity for specific wavelengths.

[0056] By using multiple photodiodes sensitive to different wavelengths and multiple LEDs emitting light at different wavelengths, it is possible to use light of multiple wavelengths simultaneously. Even without increasing wavelength selectivity, multiple wavelengths of light can be used in a time-division manner by transmitting and receiving light of a specific wavelength in a specific time slot.

[0057] Arteries in living organisms exhibit pulsation, and this pulsation can be detected using the principle of a photoplethysmogram (PPG). Oxygenated and deoxygenated hemoglobin in living arteries have different wavelength-dependent light absorption rates, and transcutaneous arterial oxygen saturation (SpO2) can be determined by performing PPG measurements using two types of light with different wavelengths. If the AC and DC components of the received signals of the two types of light are denoted as AC1, DC1, AC2, and DC2, respectively, then SpO2 can be calculated using equations 2 and 3. The relationship between R and SpO2 in equation 3 was determined experimentally, and a, b, and c are coefficients of the curve approximation determined experimentally.

[0058]

number

[0059]

number

[0060] Red light can be used to measure AC1 and DC1, and near-infrared light in the 800nm ​​to 900nm range can be used to measure AC2 and DC2.

[0061] Furthermore, there are glucose absorption bands in the 1100nm and 1600nm wavelength ranges, and blood glucose levels in a living organism can be determined using light of these wavelengths. In addition, various other substances, such as alcohol in the blood, can be measured using a similar method. [Examples]

[0062] Figure 6 is a diagram of the configuration of Embodiment 2 relating to the first embodiment of the present invention. The power supply unit 104 is located outside the outer shell structure 201. The power supply unit 602 has the power supply unit 104 inside and is covered by the outer shell structure.

[0063] The optical transceiver unit 101, the stress transmission unit 102, the communication unit 103, the outer shell structure 201, and the connector 603 constitute the biosignal measurement unit 601. The power required for measurement by the biosignal measurement unit 601 is supplied from an external power supply unit 602 via the connector 603.

[0064] Connector 603 has electrodes so that it can be attached and detached. Power supply unit 602 also has electrodes that mechanically contact and electrically connect with the electrodes of connector 603. The electrodes and the surrounding resin can have a textured surface to prevent them from coming loose due to vibration or other reasons. A mechanism can be provided to prevent reverse insertion of the positive and negative terminals when supplying power. The textured surface can also be used as a reverse insertion prevention mechanism.

[0065] Figure 7 is an overhead view of Embodiment 2. The biosignal measurement unit 601 is attached to the end of the temple of the eyeglasses 301. Further beyond that, the power supply unit 602 is positioned via a connector 603. As shown in the enlarged view, the connector 603 may also be provided on the third level of the biosignal measurement unit 601 to connect the power supply unit 602. Alternatively, the connector 603 may be provided on the opposite side of the optical transceiver unit 101 to position the power supply unit 602 on the fourth level.

[0066] By making the power supply unit 602 detachable, for example, a replacement power supply unit 602 can be prepared and used to replace the power supply unit 602 when its battery level becomes low. This has the effect of minimizing the time that biosignal measurement is stopped when the power supply unit 602 is being charged. Continuously acquiring data in biosignal measurement is sometimes important for understanding the state of the living body. This avoids periods of several hours of data loss due to charging. [Examples]

[0067] Figure 8 is a diagram of the configuration of Embodiment 3 relating to the first embodiment of the present invention. It has a second external structure 801 in addition to the first external structure 301 that penetrates the cavity.

[0068] The second external structure 801 is mechanically connected to the outer shell structure 201 and power supply unit 602 of the biosignal measurement unit 601. This allows the second external structure 801 to exert stress on the stress transmission unit 102 via the outer shell structure 201. Since the stress transmission unit 102 can transmit stress to the optical transmitting / receiving unit 101, the second external structure 801 can also exert stress on the optical transmitting / receiving unit 101.

[0069] Furthermore, the second external structure 801 has electrical wiring and electrically connects the power supply unit 602 and the biosignal measurement unit 601. In other words, it supplies power to the communication unit 103 and the optical transceiver unit 101 inside the biosignal measurement unit 601. A connector 603 is provided in the middle of the second external structure 801. The connector 603 has a first polarity 603a and a second polarity 603b, allowing it to be attached and detached mechanically and electrically.

[0070] Figure 9 is an overhead view of Embodiment 3. A pair of glasses 301 is used as the first external structure 301. The temples of the glasses 301 penetrate the cavity 102a and apply stress to the temporal lobe via the stress transmission section 102. A power supply unit 602 is installed on the opposite temple. The second external structure 801 mechanically and electrically connects the biosignal measurement unit 601 and the power supply unit 602 via a connector 603. The second external structure 801 mechanically connects the temples facing each other across the head, generating tensile stress between the temples. The tensile stress acts on the optical transceiver 101 and further on the living body via the stress transmission section 102 in the biosignal measurement unit 601. As shown in the enlarged view, the second external structure 801 may be extended from the third floor of the biosignal measurement unit 601.

[0071] By providing a pad 901 on the upper part of the rim of the eyeglasses 301, the structure consisting of the eyeglasses 301 and the second external structure 801 can be more stably fixed to the head.

[0072] The second external structure 801 is made of an elastic material, which allows it to generate tensile stress in relation to elongation according to the spring constant. The generated stress can be adjusted by providing an adjustment mechanism to adjust the length of the second external structure 801. The stress adjustment mechanism can also be realized by providing a cavity 102a in the outer shell structure of the power supply unit 602, similar to that of the biosignal measurement unit 601, and making it movable from the temple tip to the temple of the eyeglasses 301.

[0073] The power supply unit 602 is replaceable with another unit, and has the same effect as in Embodiment 2. The stress applied to the stress transmission unit by the second external structure 801 can be used to optimize the subcutaneous stress described above. Furthermore, it has the effect of suppressing misalignment of the contact between the optical transmitting / receiving unit 101 and the skin due to acceleration such as vibrations and shocks applied to the glasses 301 and the biosignal measurement unit 601 during biological movement. In addition, by separating the mass of the power supply unit 104 from the optical transmitting / receiving unit 101 and the stress transmission unit 102, the influence of the mass of the power supply unit 104 and the load caused by external acceleration can be eliminated. [Examples]

[0074] Figure 10 is an overhead view of Embodiment 4 relating to the first embodiment of the present invention. Multiple biosignal measurement units 601 are arranged on the eyeglasses 301 and connected by a second external structure 801, and a power supply unit 602 is placed between the second external structures 801.

[0075] In addition to having the same effects as in Example 3, a diversity effect occurs due to the multiple biosignal measurement units 601. When measuring photoelectric pulse waves, the desired signals are pulse wave waveforms and heart rates. Motion artifacts (MA) superimpose noise onto the waveform. The causes of noise include fluctuations in the optical path due to displacement of the skin or biosignal measurement units 601 caused by the movement of the living body, and the aforementioned changes in the pressure applied subcutaneously. In some cases, the blood flow at the measurement site is affected by acceleration, which is a genuine effect. The diversity effect cannot be eliminated if the noise behavior at two points is exactly the same, but in many cases the behavior at two points is not exactly the same. In particular, when measuring at distant sites or on the opposite side of the head, there is diversity in the behavior of skin and sensor displacement, the direction of the vector that modulates the applied pressure, and the behavior of blood flow being compressed or released.

[0076] Signal processing techniques that utilize this diversity effect include selective synthesis, which switches between multiple optical signals according to their signal-to-noise ratio (SNR); equal-gain synthesis, which combines multiple signals with the same gain; and maximum-ratio synthesis, which combines multiple signals weighted according to their SNR. The effects described in Example 3, along with the diversity effect, enable robust biosignal measurement against MA (Magnetic Amplifier).

[0077] The advantage of using multiple sensors is that, in addition to synthesizing them to obtain a single biological signal, they can also be processed independently to obtain biological information for each specific body part. For example, by performing the aforementioned SpO2 measurement at each body part, information on oxygen consumption at each part can be obtained. The same can be said for glucose and alcohol measurements. [Examples]

[0078] Figure 11 is a diagram of the configuration of Embodiment 5, which relates to the first embodiment of the present invention. The biosignal measurement unit 1101 has a connector 603 on the inner wall of the cavity 102a.

[0079] The biosignal measurement unit 1201 in Figure 12 similarly has a connector 603 on the inner wall of the cavity 102a, but differs from Figure 11 in that it does not have a power supply unit.

[0080] Figure 13 is an overhead view of Embodiment 5. A biosignal measurement unit 1101 with a power supply unit 104 and a biosignal measurement unit 1201 without a power supply unit are placed on the glasses 301. The glasses 301 have electrical wiring and are in contact with the connectors 603 of each biosignal measurement unit. Power for the biosignal measurement unit 1201 without a power supply unit is supplied from the biosignal measurement unit 1101 with a power supply unit 104.

[0081] The electrical wiring for eyeglasses 301 can be routed in two lines on one side of the temple or end piece, or one line on each side. Gold, which is rust-resistant and durable, can be used for the electrical wiring and connector 603.

[0082] Figure 14 shows an example in which multiple biosignal measurement units 1201, which do not have a power supply unit, are arranged and power is supplied from a power supply unit 602 located on the second external structure 801.

[0083] As shown in the enlarged view, a connector 603 is also placed on the side of the biosignal measurement unit 1201 and connected to the electrical wiring of the second external structure 801. Furthermore, power is supplied to multiple biosignal measurement units 1201 via the connector 603 on the inner wall of the cavity 102a and the electrical wiring of the eyeglasses.

[0084] In the examples in Figures 13 and 14, two biosignal measurement units are placed on one side, but even more biosignal measurement units may be placed.

[0085] Using multiple biosignal measurement units complicates the handling of biosignals measured by each unit. When short-range wireless communication (PAN) is used as the communication unit 103, there is a limit to the number of peripherals that can be used simultaneously. One solution is to give the communication unit 103 a scheduling function, allowing each unit to have a protocol that transmits only during its own specific time slot.

[0086] Alternatively, the communication unit 103 can be equipped with power line communication capabilities to collect the biosignals acquired through the electrical wiring of the glasses 301 in one location. After appropriate processing such as compression and abstraction, the collected data can be transmitted externally via short-range wireless communication from the unit.

[0087] This embodiment has the same effect as Embodiment 4. Functional near-infrared spectroscopy (fNIRS) can also be performed using multiple biosignal measurement units. Brain functions related to language and hearing are localized in the temporal lobe, making real-time vectorization meaningful. By using light of multiple wavelengths, it is possible to obtain not only oxygen consumption and blood flow but also other information. [Examples]

[0088] Figure 15 is a configuration diagram of Embodiment 6 relating to the first embodiment of the present invention. In Figure 15(a), there is a biosignal measurement unit 1101 having a power supply unit 104 and a biosignal measurement unit 1201 without a power supply unit, and the power of the power supply unit 104 is shared through a connector 603 arranged on the inner wall of the cavity 102a and electrical wiring arranged on the first external structure 301.

[0089] In Figure 15(b), all of the biosignal measurement units 1201 do not have a power supply unit, and these biosignal measurement units 1201 utilize the power supplied to the electrical wiring of the first external structure 301.

[0090] Figure 16 is an overhead view of a biosignal measurement device having the configuration shown in Figure 15(a). Two rows of the first external structure 301 are shown, but more rows may be arranged. The biosignal measurement unit 1101, which has a power supply unit 104, is located in the center, but it may be located anywhere. The battery in the power supply unit 104 may be charged, for example, through the electrical wiring of the first external structure 301.

[0091] The headband 1601 integrates multiple biosignal measurement units, each including a first external structure 301 arranged in multiple rows. It holds each biosignal measurement unit while the optical transceiver 101 is in contact with the skin. Each biosignal measurement unit is movable to accommodate the size of the body's head and the area to be measured. The headband 1601 can be made of an elastic material such as resin. A fabric portion to absorb sweat may also be provided.

[0092] Figure 17 is an overhead view of a biosignal measurement device having the configuration shown in Figure 15(b). Two rows of the first external structure 301 are arranged, but more rows may be arranged. The power required for the operation of the biosignal measurement unit 1201, which does not have a power supply unit 104, is supplied from the power supply unit 602 via the first external structure 301 and the second external structure 801. The first external structure 301 and the second external structure 801 are detachable via a connector 603.

[0093] The headband 1601 integrates multiple biosignal measurement units, including a first external structure 301 with multiple rows. The headband 1601 may also integrate the second external structure 801 and the power supply unit 602 as a whole.

[0094] By arranging multiple rows of the first external structure 301 and arranging the biosignal measurement units 1101 and 1201 in an array, the spatial resolution of fNIRS is improved. To measure the frontal lobe, temporal lobe, and other regions, elastic material can be used in the first external structure 301 to apply stress to the head and fix its position.

[0095] By reducing the number of power supply units 104 or stress-straining the power supply unit 602 away from the biosignal measurement unit, the mass of each biosignal measurement unit can be reduced, thereby minimizing the effects of acceleration.

[0096] Each biosignal measurement unit can be moved to any desired position, allowing for the selection of the mounting location while accommodating individual differences according to the desired brain function measurement. [Examples]

[0097] Figure 18 is a configuration diagram of Embodiment 7 relating to the first embodiment of the present invention. The optical transmitting / receiving unit 101, the communication unit 103, and the power supply unit 104 are arranged below the stress transmission unit 102.

[0098] A belt can also be used as the first external structure 301 that penetrates the cavity 102a. When worn on the ankle or the like, it is less likely to slip and can apply appropriate stress. The stress from the belt 301 is transmitted from the bottom surface of the cavity 102a to the optical transceiver 101 via the communication unit 103 and the power supply unit 104.

[0099] Figure 19 is an outline view of Embodiment 7. By positioning each part below the belt 301, the protrusion above the belt can be reduced. To reduce the height that protrudes from the skin, the communication unit 103 and the power supply unit 104 may be recessed in the parts that overlap with the optical transceiver unit 101. If the belt 301 is made of an elastic material such as a string, stress can be easily adjusted by changing the material, width, length, etc., and in this example, no protrusions are provided around the optical transceiver unit 101.

[0100] Figure 20 is an overhead view of Example 7. In this example, the biosignal measurement unit 1801 shown in Figure 18 is attached to the ankle of a living person using a belt 301. A relatively large PPG signal can be obtained on the inside of the ankle. Since it is far from the head, the SNR can be improved by measuring in conjunction with the head from a diversity perspective. In office work, manufacturing line work, and daily life, there are many cases where the movement is less than that of the wrist or fingers. It can be secured with socks or shoes to prevent slipping, or it can be embedded in socks or shoes.

[0101] Measurements can be taken at the head and ankle, and pulse wave velocity (PWV) can also be measured between the head and ankle. For PWV, cfPWV (measured between the carotid and femoral arteries) and baPWV (measured between the upper arm and ankle) are commonly performed. The latter has a stronger correlation with blood pressure. PWV is expressed by equation 4, where E is the Young's modulus of the artery, h is the arterial wall thickness, D is the arterial diameter, and ρ is the blood viscosity. The stiffer the artery, the thicker the arterial wall, and the smaller the arterial diameter, the faster the PWV. Conversions can be performed according to the measurement site and height.

[0102]

number

[0103] In particular, at the ankle, waveform distortion can occur due to propagation along long paths, leading to errors in velocity calculations. To minimize errors, the rising edge of the PPG waveform during systole is often used. While propagation velocity can also be calculated from the correlation between two points, distortion can still cause errors. Alternatively, the frequency characteristic that distorts the waveform can be multiplied by its inverse frequency characteristic to restore it to its original state.

[0104] When measuring PWV in real time for purposes such as correlation with blood pressure, waveform distortion caused by MA (Magnetic Amplifier) ​​becomes a problem. This invention reduces mass and allows the device to be attached to areas with high SNR (Signal-to-Noise Ratio). Furthermore, it can be attached to multiple locations on the foot, such as both left and right feet, or to the inner and outer sides of the foot, to improve SNR through the diversity effect.

[0105] (Second Embodiment) Figure 21 is a diagram showing the configuration of a second embodiment of the biosignal measurement device of the present invention. An optical transceiver unit 101, a stress transmission unit 102, a communication unit 103, and a power supply unit 104 are arranged on the body, and these constitute the biosignal measurement device 2100.

[0106] The stress transmission unit 102 has a groove 102a. The stress transmission unit 102 transmits the stress generated by the first external structure 301 passing through the groove 102a to the optical transmitting and receiving unit 101.

[0107] Figure 22 shows how the stress acts at this time. It is assumed that biological surface 1 is the back surface of the ear, biological surface 2 is the surface of the temporal lobe, and the first external structure 301 is the mask strap. When the mask strap 301 is placed over the ear, a stress 2201 is applied to the back of the ear along the temporal lobe. This stress applies a stress vector 2202a perpendicular to the optical transmitting / receiving unit 101 and a stress vector 2202b via the stress transmission unit 102. The stress that presses the optical transmitting / receiving unit 101 against the skin is this perpendicular stress vector 2202a. The horizontal stress vector 2202b tries to shift the optical transmitting / receiving unit 101 horizontally, but it is canceled out by the stress vectors 2203a and 2203b acting on the surface of the temporal lobe. In other words, the biosignal measurement device 2100, including the optical transmitting / receiving unit 101, is fixed in place. [Examples]

[0108] Figure 23 is an outline view of Embodiment 8 relating to the second embodiment of the present invention. The explanation assumes that it is positioned between the back of the ear and the temporal lobe. The optical transmitting / receiving unit 101 is positioned in contact with the surface behind the ear. The stress transmission unit 102 also serves as the outer shell structure, covering and protecting each part, and has a groove 102a that transmits the force acting on the groove 102a to the optical transmitting / receiving unit 101 and its surrounding structure. The stress transmission unit 102 has a wedge-shaped structure (V-shaped structure) that is in contact with the surface behind the ear and the surface of the temporal lobe, and as shown in Figure 22, it is fixed to the back of the ear and applies stress to the subcutaneous tissue. In other words, it is a mechanism that receives stress from the mask string and converts it into stress acting perpendicularly to the first surface, the back of the ear, and supports the horizontally acting force with the second surface, the temporal lobe, to prevent movement. The stress transmission unit 102 may have an opening where the optical transmitting / receiving unit 101 is located.

[0109] The communication unit 103 can be positioned, for example, behind the ear, in the V-shaped structure. The power supply unit 104 can be positioned, for example, on the temporal lobe side of the V-shaped structure. This allows for a compact design and reduced mass while maintaining the above-mentioned stress mechanism.

[0110] Figure 24 is an overhead view of Embodiment 8. The filter portion 2401 and the string portion 301 of the mask are attached to the face, and tensile stress is generated in the string portion 301. The biosignal measurement device 2100 is placed in the area where the string portion 301 passes behind the ear. In positioning, as shown in Figure 21, the string portion 301 passes through the groove 102a and the optical transmitting / receiving unit 101 is set to contact the area behind the ear.

[0111] The ear contains cartilage in region 2402, which has an elastic structure composed of collagen. By using an elastic material for the stress transmission section 102 and sandwiching the artery between the upper and lower elastic bodies, even stress application can be expected. The earlobe lacks cartilage and is prone to vibration, so it is best to avoid placing the optical transmitting / receiving section 101 in the earlobe. Relatively large arteries run through the upper and lower parts of region 2402, which contains cartilage, so it is best to place the optical transmitting / receiving section 101 in this vicinity.

[0112] In particular, the upper part of the cartilage region 2402 has an upward slope of about 45 degrees, and placing the optical transceiver on this upward slope makes it a desirable mounting location for detecting relatively large arterial blood flow. Because it rests on the upper part of the ear, the risk of slipping off when large acceleration is applied is also reduced. Gravitational acceleration pulls the mass of the biosignal measurement device 2100 downwards in standing and sitting positions, so this load can also be used as stress. Instead of applying stress with the string portion 301, it is also possible to apply stress with the temple tips of the glasses, or with both the string portion 301 and the temple tips, depending on the circumstances.

[0113] The artery in the upper part of the cartilage region 2402 is located in a depression extending from the helix towards the temporal lobe, and since the artery is located around this depression, the depression can be used as a landmark. As shown in Figure 23, the stress transmission portion 102 is given a protrusion 102b and a shape that fits into this depression, making it easier to insert.

[0114] The mask strap portion 301 generates a load of approximately 100 gf when fully stretched. Since it is typically used stretched to about 10 to 20%, and on average about 15%, a load of approximately 15 gf is applied to the upper and lower parts of the ear. Because the load is not large, it is preferable to optimize the area over which the stress is applied, considering the stress required to increase the aforementioned optical signal. The convex portion 102b concentrates the stress around this area, allowing for effective application of stress to the subcutaneous arteries using a small load.

[0115] The shape of the protrusion 102b can be rounded or matched to the shape of a cavity in the body. This allows for effective stress application and reduces discomfort to the skin. It is also possible to control stress concentration and dispersion by using a material with a low elastic modulus for the stress transmission part 102.

[0116] The biosignal measuring device 2100 and the mask strap portion 301 can be combined to form an integrated structure with the mask as appropriate.

[0117] Since the stress vector of the string portion 301 is located along the temporal lobe, it is best to point the optical transmitting / receiving unit 101 towards the back of the ear. However, if the acceleration due to the movement of the living body is small, it is possible to use the optical transmitting / receiving unit 101 facing towards the temporal lobe.

[0118] The optical transceiver 101 can be positioned near the artery in the lower part of the cartilage region 2402, with the remaining portion positioned behind the earlobe. While it is generally best to avoid placing the optical transceiver 101 directly on the earlobe, there is a relatively large space behind the earlobe, making it meaningful to place the other parts there. This is particularly convenient when sleeping on one's side, as it creates space behind the earlobe.

[0119] Although groove 102a is shown as open in Figure 23, etc., it can also be made narrower to prevent the string portion 301 from coming loose once it is set. This prevents the biosignal measuring device 2100 from falling.

[0120] Masks are commonplace in daily life, and it is meaningful to use the stress generated by masks to act on subcutaneous capillaries and increase the PPG signal. A method is needed to accurately capture the limited arterial blood flow behind the ear, which can be achieved with the configuration of this invention. The head moves less in daily life compared to the limbs, so MA can be suppressed. The amount of optical signal can also be increased, so the SNR is improved.

[0121] The stress of the cord portion 301 is effectively transmitted subcutaneously, and shearing can be suppressed by utilizing two surfaces of the living body, thereby suppressing MA and improving SNR. By positioning each part near the two surfaces of the living body, the design can be made compact and the mass can be reduced.

[0122] Even if there are individual differences in the location, size, and shape of the body parts, the groove 102a allows for adjustment, enabling optimal placement.

[0123] (Third Embodiment) Figure 25 is a diagram showing the configuration of the third embodiment of the biosignal measurement device of the present invention. In the second embodiment, the angle of the space sandwiched between the living body was 180 degrees or less, but in the third embodiment, the angle of the space side between living body surface 1 and living body surface 2 is 180 degrees or more. An L-shaped biosignal measurement device 2500 is placed in such a location. An optical transmitting / receiving unit 101 is placed on living body surface 1, a communication unit 103 is placed on the upper part of living body surface 1, and a power supply unit 104 is placed on the upper part of living body surface 2. The entire device is covered by a stress transmission unit 102, but the area around the optical transmitting / receiving unit 101 may be left open.

[0124] Figure 26 shows the effect of stress in the third embodiment. The explanation assumes that the biosignal measurement device 2500 is attached to the tip of the nose and that stress is applied to the biosignal measurement device 2500 from the filter portion 2401 of the mask.

[0125] The stress vector 2601 from the mask's filter portion 2401 acts to press the entire biosignal measurement device 2600 against the tip of the nose. The stress vector 2601 is decomposed via the stress transmission portion 102 into a vector 2602a acting perpendicularly to the biosurface 1 and a vector 2602b acting horizontally. The perpendicularly acting vector 2602a acts on the biosurface 101 and the surrounding subcutaneous capillaries, increasing the optical signal. The horizontally acting vector 2602b would otherwise act to shift the biosurface 101, but due to the L-shaped structure, it cancels out with the stress vector 2603 acting on the biosurface 2, and its position is fixed. [Examples]

[0126] Figure 27 is an outline view of Embodiment 9 relating to the third embodiment of the present invention. A protrusion 102b is provided on the L-shaped optical transmitting / receiving unit 101. This is to effectively transmit the stress from the stress transmission unit 102 to the subcutaneous tissue. As mentioned above, the load on the mask is small, and even in the filter portion of the mask, the load on the tip of the nose is about 20 gf. The stress is increased by making only the optical transmitting / receiving unit 101 and its surrounding area come into contact with the skin.

[0127] This biosignal measurement device 2500 is designed to be worn on the tip of the nose, but by placing the temperature sensor 2701 near the nostril, it is possible to detect respiration. During inhalation, outside air flows into the vicinity of the nostril inside the mask, and during exhalation, air from the lungs flows in. By measuring the temperature near the nostril inside the mask, the temperature difference between inhalation and exhalation can be detected, and the respiratory rate can be measured. The temperature sensor 2701 can be a thermistor, thermocouple, infrared sensor, etc. Alternatively, a flow sensor can be used to determine the inhalation and exhalation flow rates instead of a temperature sensor.

[0128] Figure 28 is an overhead view of Example 9. The biosignal measurement device 2500 is attached to the tip of the nose, and then a mask is worn. Tensile stress is generated in the filter portion 2401 and the string portion 301 of the mask, mainly due to the elongation of the string portion 301. The tensile stress acting on the filter portion 2401 of the mask acts in a direction that presses the tip of the nose against it. It is preferable to position the biosignal measurement device 2500 near the nose tip, close to the nose fit wire 2801. Even if the biosignal measurement device 2500 is not directly below the nose fit wire 2801, the biosignal measurement device 2500 attached to the tip of the nose is positioned higher than the surrounding area, so it comes into contact with the filter portion 2401, and stress from the filter portion 2401 is transmitted.

[0129] In the human body, the tip of the nose also has cartilage and possesses an elastic structure. While the nasal alae are displaced by breathing and speaking, the nasal tip is relatively less displaced, which is advantageous for reducing MA (Multiple Absorption). Compared to methods of attaching clips to the nasal alae, placing them on the nasal tip can suppress infection of the mucous membrane and mechanical damage. The nasal tip also has a region where the optical signal is large, similar to the nasal alae, making it suitable for improving SNR (Signal-to-Noise Ratio). Since it is easier to obtain larger optical signals on the left and right sides of the nasal tip ridge than on the ridge itself, it is preferable to place the optical transmitting and receiving unit 101 on the L-shaped surface.

[0130] The tip of the nose is steep but slopes upward, and positioning the optical transmitting / receiving unit 101 on this upward slope reduces the risk of slippage and is meaningful in that it also utilizes gravitational acceleration as a stress. Since the amplitude of the optical signal tends to weaken towards the nasal bone at the tip of the nose, it is preferable to attach it to a part close to the nostril.

[0131] The shape of the protrusion 102b can be rounded, or a material with a low modulus of elasticity can be used to control stress concentration and dispersion as appropriate.

[0132] Even if there are individual differences in the location, size, and shape of body parts, the L-shaped structure can be moved to ensure optimal placement. Furthermore, by giving the L-shaped structure an elastic component and making the angles of the first and second surfaces adjustable, it can accommodate individual differences in the angle of the nasal tip.

[0133] An adhesive layer can be provided at the point where the biosignal measuring device 2500 and the filter portion 2401 of the mask come into contact, thereby creating an integrated structure with the mask, as appropriate. [Examples]

[0134] Figure 29 is an overhead view of Embodiment 10 relating to the third embodiment of the present invention. A biosignal measuring device 2500 is attached to the tip of the nose, and an eye mask 2901 is worn. A biosignal measuring device 2100, which is attached to the ear, can also be worn simultaneously or instead. Biosignals can be acquired as appropriate, such as by using a mask that covers the mouth and nose during the day and an eye mask when sleeping.

[0135] The following block functions, which are common to the first to third embodiments, will be described.

[0136] Figure 30 is an example of a block diagram of the optical transceiver unit 101. It consists of a green LED 3001, a red LED 3002, a first near-infrared LED 3003, a second near-infrared LED 3004, a first photodiode 3005, and a second photodiode 3006.

[0137] Green light exhibits greater attenuation in subcutaneous tissue compared to other wavelengths, but it is robust to MA (Magnetic Absorption), making it preferable to use a green LED when measuring pulse rate, heart rate variability, or PWV (pulse wave velocity). On the other hand, when measuring SpO2, it is preferable to use red light and near-infrared light in the 900nm range as the two wavelengths in equations 2 and 3 mentioned above. Furthermore, blood glucose levels can be measured using near-infrared light in the 1100nm and 1600nm ranges.

[0138] The photodiode receives the light emitted from these LEDs after it has passed through the living body. In addition to a reflective configuration in which light scattered by the living body returns to the vicinity of the LED, in the third embodiment, the LED and photodiode (PD) can be separately arranged on the first and second surfaces of an L-shaped structure to receive light transmitted through the living body. Furthermore, with the present invention, multiple biosignal measurement units can be placed in various parts of the body, and it is also possible to measure between any two biosignal measurement units A and B by receiving the light output from the LED of A with the PD of B.

[0139] By using two types of photodiodes (PDs), one can be used for optical communication (described later) and the other for biosignal measurement. This has the advantage of allowing optical communication and biosignal measurement to be performed simultaneously.

[0140] Figure 31 is an example of a block diagram of the communication unit 103. It consists of a control circuit 3101, a timer 3102, an RF circuit 3103, and a DC-DC converter circuit 3104.

[0141] The control circuit 3101 controls the LEDs, processes optical signals received by the PD, manages the time and power supply, and controls signal exchange with external devices. If other sensors are installed (as described later), it also controls and processes their signals.

[0142] Timer 3102 keeps time with the precision necessary for processing biological signals. Pulse wave interval fluctuations (PRV) have recently been studied in comparison with conventional heart rate variability (HRV) measured using ECG, and nearly equivalent accuracy is beginning to be achieved in environments with low MA. To minimize MA and obtain accuracy equivalent to HRV even under biological movement, this invention also employs a method of synthesizing multiple PD signals using diversity effects, etc. Accurate timing between each biological signal measurement unit is necessary for synthesis.

[0143] For heart rate variability, a sampling frequency of approximately 1 kHz is used, and an accuracy of less than 1 millisecond is desired. Using a crystal oscillator can achieve an accuracy of several tens of ppm, but in order to keep the time between multiple units within the above accuracy, time synchronization needs to be performed approximately once every 100 seconds. Optical communication, which will be described later, can also be used as a means of performing this time synchronization.

[0144] The RF circuit 3103 performs wireless communication with the outside. If the signal from the optical transceiver 101 is routed in analog form, the number of wires between boards and units increases, and noise is introduced. It is preferable to convert the signal to digital before these problems occur and send it to another biosignal measurement unit or a nearby terminal. This is especially noticeable when using multiple biosignal measurement units for MA countermeasures. The same applies when receiving instructions from the outside, such as settings for the optical transceiver 101.

[0145] As one method of communicating with the outside world, the RF circuit 3103 can perform wireless communication using short-range wireless communication or a body area network.

[0146] A second method is to perform power line communication. This method involves superimposing the communication signal onto power wiring, such as when the power supply unit 104 is located externally or when multiple biosignal measurement units share a power supply. The RF circuit 3103 can also perform modulation, demodulation, and error correction.

[0147] A third method involves optical communication. This utilizes LEDs or PDs on both the nearby unit and the terminal. Near-infrared light can be used as the wavelength of light. In addition to real-time communication during biological measurement, stored data can also be communicated at the start and end of attachment. Modulation, demodulation, and error correction can also be performed by the RF circuit 3103.

[0148] The DC-DC converter circuit 3104 generates the voltages required by the control circuit 3101, timer 3102, and RF circuit 3103.

[0149] Figure 32 shows an example of a block diagram of the power supply unit 104. It consists of a battery 3201 and a charging circuit 3202. The charging circuit 3202 charges the battery 3201 by receiving power supplied from an external source during charging. The power supply unit 104 may be located outside the biosignal measurement unit. In that case, it is preferable to have as few power wirings as possible between the power supply 104 and the biosignal measurement unit. If only two power wirings are used, the charging circuit 3202 can be omitted, and the voltage of the battery 3201 can be directly transmitted through the power wiring. The charging circuit 3202 can be located externally.

[0150] Alternatively, the power supply unit 104 can retain the charging circuit 3202 and also incorporate a switch circuit to switch between charging mode and the discharge mode used during normal operation. The switch circuit monitors the voltage of the power supply wiring and switches to discharge mode if the voltage is below a predetermined level, and to charging mode otherwise. By keeping it in charging mode under normal conditions, charging is possible even if the battery has discharged below the predetermined voltage and the monitoring circuit is not activated.

[0151] (Fourth Embodiment) Figure 33 is a block diagram of the fourth embodiment of the biosignal measurement device of the present invention. In addition to the components of the first to third embodiments, it includes an accelerometer 3301, a thermometer 3302, a flow meter 3303, an environmental measurement sensor 3304, and a microphone 3305, which constitute the biosignal measurement device 3300.

[0152] The accelerometer 3301 measures acceleration, angular velocity, and orientation in three axes. It can also measure position and altitude by incorporating GPS or other technologies.

[0153] The thermometer 3302 can be used as the temperature sensor 2701 in Figure 27 to measure skin temperature and core body temperature. Thermistors, thermocouples, infrared sensors, heat flow meters, etc., can be used.

[0154] The flow meter 3303 can be used to measure respiration in place of the temperature sensor 2701 shown in Figure 27, or to measure the flow of gas inside and outside of clothing.

[0155] The environmental measurement sensor 3304 measures physical and chemical quantities of the environment. These include temperature, humidity, pressure, illuminance, sound, odor, wind speed, air composition, and chemical substances. The surrounding environment of living organisms may also be measured using visible light or infrared sensors or cameras.

[0156] The microphone 3305 measures sound. It may also measure vibrations, shocks, and ultrasound. Multiple microphones and transducers may be used to measure the surrounding three-dimensional structure.

[0157] In addition to obtaining various biological information, including biological information from the optical transceiver 101, it is also possible to obtain information about the physical and chemical state of the environment surrounding the living organism, the context of the living organism, that is, the meaning of the situation in which the living organism is placed, and information such as eating, sleeping, exercising, working, resting, riding in vehicles, talking, attending classes, shopping, being in a crowd, attending meetings, and working.

[0158] Figure 34 is a block diagram of a fourth embodiment of the biosignal measurement system of the present invention. The biosignal measurement system 3400 is configured using a biosignal measurement device 3300, as well as the biosignal measurement devices 100, 2100, and 2500 described in the first to third embodiments, as well as a terminal 3401 and a server 3402.

[0159] Each biosignal measurement device can communicate directly with terminal 3401, or it can communicate with each other first and then communicate with terminal 3401 collectively. Communication data can be reduced by performing compression / decompression, abstraction, and modulation / demodulation processing as needed.

[0160] The allocation of functions performed by the biosignal measurement devices 100 to 3300, terminal 3401, and server 3402 is determined by the functions and resources of each component, and can be changed statically or dynamically. The biosignal measurement devices 100 to 3300 can be equipped with various sensors, relatively small capacity batteries, relatively low processing power CPUs, and small memory capacity in order to reduce mass and volume. Terminal 3401 can also be equipped with various sensors, relatively large capacity batteries, and a moderately processing power CPU and moderately large memory capacity, depending on its mass and volume. Server 3402 is connected to commercial power and can be equipped with a high-performance CPU and large-capacity memory.

[0161] The access permissions also differ; for example, access from the biosignal measurement devices 100 to 3300 to terminal 3401 is set to single-user access, while server 3402 is set to multi-user access. Alternatively, terminal 3401 can be configured to communicate with biosignal measurement devices 100 to 3300 belonging to different users.

[0162] Figure 35 is a block diagram of a fourth embodiment of the biosignal measurement system of the present invention. The biosignal processing block 3500 receives signals from the biosignal measurement device 100 to 3300 and processes the biosignals. The biosignal processing block 3500 includes a time synchronization block 3501, a preprocessing block 3502, a postprocessing block 3503, an abstraction block 3504, an anonymization block 3505, and a system reconstruction block 3506.

[0163] The time synchronization block 3501 synchronizes the time of the biosignal measurement devices 100 to 3300. The source time for synchronization may be the server 3402, terminal 3401, or one of the biosignal measurement devices 100 to 3300. Accuracy of time between biosignal measurement devices is particularly important when determining MA reduction, PWV, etc.

[0164] The preprocessing block 3502 performs preprocessing on the biological signals acquired by the biological signal measurement devices 100 to 3300. It primarily performs processing to remove noise and MA within the signal band.

[0165] The post-processing block 3503 primarily performs signal synthesis processing.

[0166] Abstraction block 3504 extracts vital signs, momentum, context, and environmental state from biological signals, acceleration, and signals from environmental sensors.

[0167] Anonymization block 3505 performs anonymization processing on personal information in biometric signals.

[0168] The system reconfiguration block 3506 optimizes system parameters such as sampling time, intermittent operation, and sleep operation according to the contribution of acquired biological signals to each vital sign and the importance of each environmental sensor and acceleration sensor value.

[0169] Figure 36 is a block diagram of a fourth embodiment of the biosignal measurement system of the present invention. The biosignal application block 3600 receives data from the biosignal processing block 3500 and performs various processes using the biosignals. The biosignal application block 3600 has biosignals 3601 (3601a, 3601b) and user interface (UI) means 3602.

[0170] The biosignal 3601 may consist of multiple biosignals from a single user, from the past to the present, or biosignals from multiple users. The biosignal 3601 may include vital information, activity levels, and environmental information surrounding the organism. The stored biosignal 3601 can be sent to the biosignal processing means 3500 for processing and learning. Past biosignals 3601 of the organism itself or biosignals 3601 of other users can be sent. Biosignals 3601 stored in another location can also be referenced as appropriate. The UI means 3602 provides an interface to single users and multi-users. It can also provide an interface to different systems.

[0171] The processing of the biosignal processing block 3500 may be performed by terminal 3401, and the processing of the biosignal application block 3600 may be performed by server 3402. Alternatively, the execution contents can be swapped as appropriate. The configuration can be selected as appropriate, such as using an edge terminal placed close to the living organism as terminal 3401, or placing server 3402 locally or in the cloud. [Examples]

[0172] Figure 37 is a block diagram showing the operation of the time synchronization block 3501. The time synchronization block 3501 may include a synchronization instruction means 3701, a timing extraction means 3702, a timer reset means 3703, and a synchronization check means 3704.

[0173] The synchronization instruction means 3701 issues an optical communication instruction to, for example, the optical transceiver 101 of the biosignal measurement devices 100 to 3300. After the biosignal measurement devices are powered on, the synchronization instruction means 3701 can instruct the biosignal measurement device that will be the source of synchronization to advertise and transmit an optical signal, and the biosignal measurement device that will be synchronized can receive it. If time synchronization is required during the acquisition of biosignals, the optical communication instruction means 3701 can issue a synchronization instruction, and synchronization can be performed between biosignal measurement devices that are capable of optical communication. If power line communication is used, time synchronization can also be performed via power line communication using a similar procedure. By synchronizing several times, the clock differences between the timers can be corrected. This makes it possible to extend the interval of synchronization by optical communication.

[0174] The timing extraction means 3702 extracts the synchronization timing from a special code for time synchronization. Since noise is present in optical signals and power line communications, it is preferable to use a specific bit pattern that represents time synchronization.

[0175] The timer reset means 3703 resets the timer 3102 of the communication unit 103 of the biosignal measurement devices 100 to 3300. The synchronization start may be set to zero, or time information may be obtained from the time synchronization source and rewritten. The time of timer 3102 can be used as the data acquisition time for each sensor of the biosignal measurement device 3300.

[0176] The synchronization check means 3704 checks the timer times between the biosignal measurement devices immediately after the completion of the synchronization process, or at regular intervals after the completion of synchronization.

[0177] Figure 38 is a block diagram showing the operation of the preprocessing block 3502. The preprocessing block 3502 may have a filtering means 3801, a subtraction means 3802, and an MA generation means 3803.

[0178] The filtering means 3801 filters the optical signal from the optical transceiver 101 and other sensor signals. The optical signal includes fluctuations due to MA, fluctuations due to illumination, thermal noise, flicker noise, etc. It is necessary to determine the characteristics of the passband and stopband so that biological information is not lost. Usually there is noise and fluctuations on both the low-frequency and high-frequency sides, so it is preferable to use a bandpass filter.

[0179] The subtraction means 3802 and the MA generation means 3803 subtract and remove the fluctuations caused by MA. The acceleration and angular velocity of an acceleration sensor placed near the optical transceiver unit 101 can be used as input to the MA generation means 3803. Since acceleration and angular velocity do not perfectly match the fluctuations of the optical signal caused by MA, the MA generation means 3803 can synthesize the waveform to be subtracted so that the optical signal after subtraction is equivalent to the MA signal when stationary. The SNR after subtraction may be observed, and the MA generation means 3803 may be adjusted to maximize the SNR. This MA generation function also changes depending on the origin of MA, such as running or riding, so a biological context may be referenced.

[0180] Figure 39 is a block diagram showing the operation of the post-processing block 3503. The post-processing block 3503 may include a signal extraction means 3901, a noise extraction means 3902, an SNR calculation means 3903, a phase adjustment means 3904, a multiplication means 3905, and an addition means 3906.

[0181] The signal extraction means 3901 takes the optical signal from the optical transceiver unit 101 as input and extracts a signal waveform using the characteristic optical signal patterns of the contraction and expansion phases, through time-domain processing, frequency-domain processing, autocorrelation processing, correlation processing with a template waveform, etc.

[0182] The noise extraction means 3902 subtracts the signal waveform extracted by the signal extraction means 3901 from the original optical signal. This extracts fluctuations caused by MA (Magnetic Amplifier) ​​or external light that could not be removed in the preprocessing.

[0183] The SNR calculation means 3903 calculates the SNR from the signal waveform extracted by the signal extraction means 3901 and the noise waveform extracted by the noise extraction means 3902. The calculation can be performed using the RMS value of each waveform.

[0184] The phase adjustment means 3904 adjusts the phase and distortion of optical signals measured by multiple biosignal measuring devices. Optical signals measured at locations far from the heart, in particular, have large phase delays and distortions. The phase adjustment means 3904 removes these phase delays and distortions, and aligns the phase and distortion states between the multiple optical signals.

[0185] The multiplication means 3905 multiplies the original optical signal waveform by the SNR and applies weighting according to the SNR.

[0186] The addition means 3906 adds and synthesizes the optical signals weighted by the SNR.

[0187] The signal waveform extracted by the signal extraction means 3901 is extracted from optical signals with fluctuations such as MA, and has a certain error rate. The composite waveform added by the addition means 3906 has an improved SNR, and the error rate can be improved by extracting a signal waveform again from this composite waveform.

[0188] Figure 40 is a block diagram showing the operation of the abstraction block 3504. The abstraction block 3504 may have a classifier 4001, a principal component extraction means 4002, a heart rate extraction means 4003, a respiration extraction means 4004, a blood pressure extraction means 4005, a body temperature extraction means 4006, an SpO2 extraction means 4007, a PRV extraction means 4008, a PWV extraction means 4009, an fNIRS extraction means 4010, a momentum extraction means 4011, a context extraction means 4012, and an environment extraction means 4013.

[0189] Abstraction block 3504 calculates various vital signs of a living organism, as well as momentum, context, and environmental physical quantities from biological signals, acceleration, and signals from environmental sensors.

[0190] The classifier 4001 and principal component extraction means 4002 are used as appropriate in the extraction of vital signs, context, and environmental conditions. Several methods exist for the classifier 4001, such as support vector machines (SVM), which serve as means to find boundaries that effectively divide the data. Principal component extraction means 4002 include methods such as principal component analysis (PCA), which can be used to determine the contribution rate of each sensor value when multiple sensor values ​​influence the result.

[0191] The heart rate extraction means 4003 extracts a signal waveform from the optical signal of the optical transceiver unit 101 after removing MA through pre-processing 3502, post-processing 3503, etc., and extracts the heart rate interval from autocorrelation, etc.

[0192] The respiration extraction means 4004 uses the signal from the temperature sensor 2701 attached to the biosignal measurement device 2500 of the third embodiment to extract the respiration rate from autocorrelation, zero crossings, etc. The amplitude information and PRV of the optical signal obtained by the optical transceiver unit 101 also contain respiration information, and each component can be appropriately synthesized and used.

[0193] The blood pressure extraction means 4005 extracts blood pressure using the blood pressure component contained in the PWV and the low-frequency component contained in the PRV.

[0194] The body temperature extraction means 4006 can be selected from methods such as using a thermometer 3302 capable of measuring core body temperature, calculating it from skin temperature or exercise level, or calculating it from the correlation between heart rate and body temperature.

[0195] The SpO2 extraction means 4007 performs measurements using the optical transmitting / receiving unit 101 and calculates based on equations 2 and 3.

[0196] The PRV extraction means 4008 extracts low-frequency and high-frequency components of the PRV from the heart rate interval extracted by the heart rate extraction means 4003 by frequency analysis.

[0197] The PWV extraction means 4009 extracts the PWV using the two optical signals obtained in the configuration of Example 7 of the first embodiment. The state of the arterial blood vessel can be estimated from equation 4.

[0198] The fNIRS extraction means 4010 extracts vectors of blood flow and oxygen consumption using optical signals from multiple locations on the head obtained in the configuration of Example 6 of the first embodiment.

[0199] The momentum extraction means 4011 extracts the momentum and posture of the living organism from the signal of the accelerometer 3301.

[0200] The context extraction means 4012 identifies and extracts the aforementioned biological context from the microphone 3305, accelerometer 3301, environmental measurement 3304, etc.

[0201] The environmental extraction means 4013 uses the environmental measurement device 3304, etc., to extract the physical and chemical conditions of the environment in which the living organism is placed.

[0202] Anonymization block 3505 performs anonymization processing such as k-anonymity, l-diversity, and t-proximity, depending on the required level of anonymity.

[0203] Figure 41 is a block diagram showing the operation of the system reconfiguration block 3506. The system reconfiguration block 3506 may include a hardware information collection means 4101, a contribution rate calculation means 4102, a priority setting means 4103, a determination unit 4104, and an instruction unit 4105.

[0204] The hardware information collection means 4101 collects settings and resources from the biosignal measurement devices 100 to 3300, terminal 3401, and server 3402. Settings include sensor sampling frequency, intermittent operation, sleep operation settings, and the processing being executed. Resources include battery level, power consumption per hour, CPU load, memory and HDD usage, and the occupancy rate of each job and process.

[0205] The contribution rate calculation means 4102 calculates the extent to which each sensor and its processing contribute to the results abstracted by the abstraction block 350. For example, it calculates the contribution of multiple sensors to the obtained vital signs using principal component analysis or the like. Contributions to MA countermeasures and SNR improvement can also be included.

[0206] The priority setting means 4103 sets the priority of each result of multiple abstractions. This can be set by an administrator or a user. A system default can also be set. The settings can also be changed dynamically according to the level of risk to the living organism. For example, the priority of vital signs related to the pre-existing condition of a living organism can be set higher.

[0207] The decision unit 4104 determines whether to revise the system settings based on hardware information, contribution rates, and priorities. For example, it sets predetermined thresholds and makes a decision to revise settings for items that are below or above the threshold.

[0208] The instruction unit 4105 instructs the biosignal measurement devices 100 to 3300, terminal 3401, and server 3402 to change settings. For example, it can change the sampling frequency, change intermittent or sleep operation, or transfer specific processing from the terminal to the server. It can also instruct users or administrators if the SNR is lower than a predetermined threshold. It can also instruct users to review the installation location or replace the device.

[0209] Figure 41 is a block diagram showing the operation of UI block 3602. UI block 3602 can have biometric attribute information 4201, user access information 4202, context display means 4203, safety / risk display means 4204, and prediction information display means 4205.

[0210] The biometric attribute information 4201 represents the attributes of the organism linked to the biometric signals 3601a, 3601b, etc. This may include personal information such as the organism's name, address, height, weight, and other physical characteristics, as well as medical history and family history. The information can be anonymized as appropriate using the anonymization methods described above before being linked.

[0211] The user access management means 4202 manages the information that users can access. For example, it can grant full access to biometric attributes to the biometric individual, partial access to their administrator, and anonymized information to users searching for similar biometric attributes.

[0212] As administrators, you can designate, for example, an industrial physician for a company, a doctor in charge of a patient, a caregiver at a nursing home, a childcare worker at a daycare center, a school teacher, a site supervisor, a health center representative, a health insurance association representative, a government or administrative agency representative, or a cooperative association representative.

[0213] The context display means 4203 displays the context extracted by the context extraction means 4012. When displaying to someone other than the user, anonymization settings can be applied as appropriate.

[0214] The safety / risk indicator 4204 displays the degree of safety or danger. The degree can be determined according to vital signs, activity level, and the environment in which it is placed.

[0215] The predictive information display means 4205 can refer to similar past cases or predict future events using regression means. Access control and anonymization processing can be used as appropriate when referring to similar cases.

[0216] Multiple biosignals 3601a, 3601b, etc., can be used, including the individual's past data and data from other users with similar attributes. These can be used in processing such as the MA generation means 3803 in the post-processing block 3503, the system reconstruction block 3506, the context extraction means 4012 in the abstraction block 3504, the safety / risk display means 4204 and predictive information display means 4205 in the UI block 3602. This can enhance the effectiveness of each process and the learning effect.

[0217] When reducing MA, the accuracy of the transfer function that simulates the noise generated by MA can be improved. In system reconstruction, it provides a means to update the system's default values. Judgment thresholds and judgment functions can also be updated. It can be used for supervised learning of classifiers used in context extraction. It can also be used for learning five-level classification in safety / risk indicators, for example, in a five-level safety / risk indicator. It can also be used to improve the accuracy of linear functions, etc., in regression analysis of predictive information display.

[0218] Figure 43 shows examples of measurements taken by the inventor on various parts of the body (fingers, wrists, earlobes, and noses). The horizontal axis represents time in minutes, and the vertical axis represents amplitude. Measurements were taken at the distal phalanx of the index finger (4301), the middle phalanx of the index finger (4302), the proximal phalanx of the index finger (4303), the inner side of the wrist (4304), the earlobe (4305), and the nasal ala (4306), using near-infrared light with a wavelength in the 800 nm range. The amplitudes are large at the distal phalanx of the index finger (4301) and the nasal ala (4306). The large amplitudes seen at the boundaries of each area are noise observed when the measuring instrument is removed from the skin.

[0219] Figure 44(a) shows examples of data acquisition by the inventor on various parts of the body (various parts of the face). Green light with a wavelength in the 500 nm range was used on the earlobe 4401, antioribular crus 4402, temporal region (around the ear) 4403, temple 4404, forehead 4405, chin below the ear 4406, chin below the mouth 4407, nape of the neck 4408, ridge of the nasal tip 4409, right side of the nasal tip 4410, and left side of the nasal tip 4411. The amplitude is large on the antioribular crus 4402, which is dealt with in the second embodiment, and on both sides of the nasal tip 4410 and 4411, which are dealt with in the third embodiment. The signal is relatively small from the temporal region 4403 to the temple 4404 and forehead 4405, which are dealt with in the first embodiment, but it is measurable.

[0220] Figure 44(b) shows a magnified view of the measurement at 4411 on the left side of the nasal tip. It shows the waveform due to arterial pulsation. The waveform is caused by the systolic and diastolic phases of the heart. This is the waveform after passing through a bandpass filter and is slightly different from the original optical signal. The original optical signal fluctuates greatly with subtle body movements and cannot be illustrated at this scale.

[0221] Figure 45 shows examples of data acquisition by the inventor on various parts of the body (various parts of the foot). Green light with a wavelength in the 500 nm range was used at the medial ankle (4501), posterior ankle (4502), lateral ankle (4503), anterior ankle (4504), lateral ankle / heel side (4505), lateral ankle / instep side (4506), and instep (4507). The amplitudes at the medial ankle (4501) and lateral ankle (4503) are relatively large, making measurement in these areas preferable.

[0222] (Fifth Embodiment) Figure 46 is a diagram showing the configuration of the fifth embodiment of the biosignal measurement device of the present invention. The optical transmitting / receiving unit 101, stress transmission unit 102, communication unit 103, power supply unit 104, and outer shell structure 201 are arranged in the region surrounded by the back of the ear and the temporal region, and these constitute the biosignal measurement device 4600. [Examples]

[0223] In Figure 46, the outer shell structure 201 is shown to be in contact with, indirectly support, or penetrate parts of the optical transceiver unit 101, stress transmission unit 102, communication unit 103, and power supply unit 104, but it may also be positioned to cover these components. The outer shell structure 201 mechanically and stress-wise connects these components. In this example, the outer shell structure 201 is in direct contact with the skin surface and hair on the temporal surface. Through this mechanical and stress-wise connection, the outer shell structure 201 applies stress to three surfaces: the surface behind the ear, the surface at the base of the ear, and the temporal surface.

[0224] For example, a stress 302a is applied to the surface behind the ear, and a counteracting force 303a is exerted from the skin. Similarly, a stress 302b and a counteracting force 303b are applied to the surface at the base of the ear, and a stress 302c and a counteracting force 303c are applied to the temporal surface. By shaping the outer shell structure 201 into a fishhook shape, it comes into contact with three surfaces: the surface behind the ear, the surface at the base of the ear, and the temporal surface, and stresses are applied due to the elasticity of the outer shell structure 201 and the elasticity of the ear. These stresses originate from the stresses generated by the elasticity of the outer shell structure 201, the elasticity of the ear cartilage, and the weight of the biosignal measurement device 4600.

[0225] Furthermore, by making the outer shell structure 201 fishhook-shaped, the third external structure 4601 can be positioned in contact with the biosignal measurement device 4600. As in other embodiments, eyeglasses, a mask, or the like can be used as the third external structure 4601. Stress 302 generated by the weight and elasticity of the third external structure 4601 is added. These stresses stably fix the biosignal measurement device 4600 to the skin, and in addition to the effect of reducing MA, the pressure applied to the skin also increases the signal.

[0226] The upper part of the back of the ear is a preferred location for placing the biosignal measurement device 4600. The upper part of the back of the ear has cartilage above the ear canal, which is relatively horizontal and provides good stability. The biosignal measurement device 4600 will be mounted on the upper part of the back of the ear. During walking or running, vertical acceleration fluctuates up and down around the acceleration due to gravity. Since gravity is always used as an offset and fluctuations due to movement are added, it is difficult for acceleration to occur in the direction that pulls away from the skin.

[0227] In this embodiment, the optical transmitting and receiving unit 101 directs the direction of light ingress and egress towards the base of the ear. The head, compared to the limbs, is less prone to acceleration due to movements such as walking. There are areas without hair, which helps avoid light blocking and attenuation by hair. The inventors compared the case where the light ingress and egress were directed towards the base of the ear with the case where they were directed towards the side of the head. There was no significant difference in the pulse wave amplitude of green, red, and near-infrared light, but the magnitude of MA, that is, the magnitude of fluctuations in the optical signal due to movement, was about one-tenth to one-tenth smaller at the base of the ear.

[0228] The movements compared included those commonly seen in daily life, such as walking, speaking, eating, and neck movements. While there was no significant difference in neck movements, the MA (metamorphosis) was smaller at the base of the ear for the other movements. The masticatory muscles, the intrinsic muscles of the tongue, and the muscles involved in speaking and swallowing influence the light reflection beneath the temporal scalp. Although it varies depending on the type of movement, for example, the movement of drinking water showed the largest fluctuation in red light, with the fluctuation in near-infrared light being about half as large, and the fluctuation in green light being about one-fifth of that of red light.

[0229] Due to location dependence, there is a depression (boundary between cartilages) in the upper part of the base of the ear (near-horizontal part of cartilage region 2402 in Figure 24) through which a relatively large artery passes. Using this depression as a reference, the MA is relatively small on the posterior side of the depression (occipital lobe side). On the other hand, the pulse wave component of each light signal becomes larger as you move toward the anterior side of the depression (frontal lobe side). To make the MA small and the pulse wave component large, it is preferable to irradiate the area behind the depression, but close to the depression, with light. To facilitate positioning, by defining and observing the location of the light emission 4901 as shown in Figure 49(c) using a mirror, it is possible to irradiate light to almost the same position each time. Evaluation by the inventors revealed that the region enclosed by the back of the ear and the temporal region is a region where pulse waves can be detected even in cold winter conditions when measuring pulse waves with the fingertips is difficult.

[0230] An elastic body 4602 can be placed between the stress transmission unit 102 and the skin. The base of the ear has a lot of cartilage and little subcutaneous fat. Because there is little fat to act as a cushion, arterial compression is likely to occur, and localized decreases in SpO2 due to compression are likely to occur. This phenomenon can be suppressed by placing an elastic body 4602, which has an even lower elastic modulus than the stress transmission unit 102, between the stress transmission unit 102 and the skin. An opening can be provided in the elastic body 4602 so that light from the light transmitting / receiving unit 101 reaches the skin. A light-transmitting material can be selected as the elastic body 4602, or a light-transmitting material can be partially placed. [Examples]

[0231] As shown in Figure 47, another embodiment of the fifth embodiment, a configuration in which the optical transceiver 101 is oriented towards the side is effective in applications where MA is less likely to occur or where MA can be suppressed by MA countermeasures described later. These constitute the biosignal measurement device 4700.

[0232] When eyeglasses are used as the third external structure 4601, stress 302 acts such that the temple tips of the eyeglasses press the stress transmission part 102 against the side of the head. A downward force 302b due to the weight of the eyeglasses also acts to press against the surface of the base of the ear. In this case as well, the biosignal measurement device 4700 is stably fixed by the three surfaces: the surface behind the ear, the surface of the base of the ear, and the surface of the side of the head. An elastic material or rubber-based material similar to that of the stress transmission part 102 can also be provided in the area where stress 302b acts.

[0233] Figure 48 shows an example of the configuration around the optical transmitting / receiving unit 101 and the stress transmission unit 102 (triangular view). The optical transmitting / receiving unit 101 is fixed to the outer shell structure 201 by bonding or other means. The stress transmission unit 102, which is an elastic body, is arranged around it. An opening is provided in the part of the stress transmission unit 102 where light enters and exits. Furthermore, an elastic body 4602 is arranged around this opening. This suppresses the decrease in SpO2 due to compression as described above.

[0234] By making the width of the outer shell structure 201 approximately the same as that of the optical transceiver unit 101, the mass can be reduced without impairing the transmission of stress, enabling a compact design. The outer shell structure 201 may be configured such that the wearer can change the angle and shape to accommodate individual differences in the shape of the concha. As the outer shell structure 201, a thin metal plate, deformable resin, or the like can be used. The pressure applied to the concha can be set to an appropriate value to prevent pain around the wearing area. By providing an acute-angled triangular portion in the stress transmission unit 102, it can be worn so as to penetrate beneath the hair covering the skin surface.

[0235] As shown in FIGS. 46 and 47, the communication unit 103 and the power supply unit 104 can be sequentially stacked on the left surface of the outer shell structure 201 having a fishhook shape. As a result, the communication unit 103 and the power supply unit 104 can also be arranged to rest on the cartilage of the concha. Even in the downward irradiation of FIG. 46, a configuration similar to that of FIG. 48 can be adopted (except for differences such as the outer shell structure 201 penetrating the stress transmission unit 102). The width of the area behind the ear and on the side of the head where there is no hair is narrow, but the compact shape of this configuration enables easy wearing.

Embodiment

[0236] As another example of the fifth embodiment, as shown in FIG. 49(a), the outer shell structure 201 can be provided to cover the concha from above to below. In this case as well, the optical transceiver unit 101 can be arranged at the upper part of the base of the ear (the triangular broken line portion in the figure). Although it is also possible to arrange it below the concha, the MA due to the movement of the jaw increases as it goes lower. This position can also be selected in cases where the movement of the jaw is actively detected or in applications where the influence of the movement of the jaw is small.

[0237] Figure 49(b) similarly covers from the top to the bottom of the back of the ear, but is elongated in a tube shape. Although the space for the power supply unit 104 becomes relatively small, such a shape can also be selected according to the application. Even when lying on one's side at bedtime or the like, the ears are less likely to ache. In Figures 49(a) and (b), it is also possible to form a shape that sandwiches the ears from above and below to fix the position, and further wraps around the front side of the ears to fix the position in the front-back direction. Such a three-dimensional structure has the merit of being able to easily perform the positioning of PPG with good reproducibility.

[0238] In Examples 12 to 14, even when removing glasses or a mask which is the third external structure 4601, the biosignal measurement device remains on the back of the ear. When there is a lot of hair covering the back of the ear, it is preferable to push aside the hair and attach the biosignal measurement device. When temporarily removing glasses or a mask, it is convenient that the biosignal measurement device remains on the skin surface.

Example

[0239] Being able to measure body temperature simultaneously with SpO2 is beneficial for judging infectious diseases and lung diseases. As shown in Figure 50(a), by measuring the respective temperatures T1 and T2 with the thermometer provided on the skin surface and the atmosphere side of the stress transmission part 102, the heat flow flowing from the skin towards the atmosphere can be measured. Assuming the thermal resistance between these two thermometers is Rth, the heat flow Ith is expressed by Equation 5. Assuming the thermal resistance from the skin surface to the deep part of the living body is Rc, the deep body temperature Tc can be obtained by Equation 6. The thermometers for measuring the above temperatures T1 and T2 can be provided as the skin surface thermometer 4801 and the atmosphere side thermometer 4802 in Figure 48. Also, a PPG thermometer 4803 for appropriately measuring the temperature of PPG may be provided.

[0240]

Equation

[0241]

Equation

[0242] A PPG typically consumes a current of a few mA and causes a temperature rise of several degrees Celsius. The current and temperature rise vary depending on the current flowing through the LEDs in the PPG, the sampling rate, and the integration time. As shown in Figure 50(b), this temperature rise ΔT introduces errors into T1 and T2, and also into Tc, which is calculated using them.

[0243] To address this, this embodiment has a table 5001 of PPG conditions and ΔT, as shown in Figure 50(c), and is configured to correct ΔT according to the set PPG conditions. This table can be created by the table creation means 5100, as shown in Figure 51(a). It can be created by a step 5101 of bringing the temperature of Tc and Ta into thermal equilibrium in advance in a laboratory or the like, a step 5102 of setting the PPG for each assumed PPG condition, a step 5103 of measuring the temperature difference ΔT that occurs between T1 and T2 (such as ΔT0 in Figure 50: when all PPGs are set to off, ΔTx: when PPG settings are a, b, c, d, e, f, ΔTy: when all PPG settings are on, etc.), and a step 5104 of creating a table of ΔT. This table 5001 of PPG conditions and ΔT is stored in the memory of the biosignal measurement device, or in a terminal, server, etc.

[0244] As shown in Figure 51(b), the ΔT correction means 5110 includes a step 5111 for setting the PPG, a step 5112 for measuring the temperature of each part such as T1 and T2, a step 5113 for referring to a table, and a step 5114 for subtracting ΔT, and a Tc with ΔT corrected can be obtained from equations 7 and 6.

[0245]

number

[0246] This embodiment relates to the preprocessing block 3502 in Figure 35 of the fourth embodiment. As shown in Figure 52, the filter means 3801 is connected after the subtraction means 3802 and the MA generation means 3803. When a large MA is generated, vibration may occur in the filter, and this vibration may continue for some time, so this connection may be preferable.

[0247] Figure 53 shows a more detailed view of the preprocessing block 3502. For example, a photodiode (PD) signal (G) from a green LED, a PD signal (Red) from a red LED, or a PD signal (IR) from a near-infrared LED can be used as input. LEDs of other wavelengths may also be used. Multiple signals within the same unit, or multiple signals between different units, may also be used.

[0248] The averaging function 5301 averages each of the above signals. For example, a moving average can be used as the averaging method. The time constant of the moving average can be set to a time constant at which the pulse wave decays. This makes it possible to generate an MA component in which the pulse wave component is suppressed. If the time constant is made too large, distortion will occur in the MA component, so it is preferable to select a time constant at which the pulse wave decays to about one-tenth.

[0249] Delay rejection 5302 restores the delay of the averaged signal. The inverse function of the averaging transfer function can be used. For example, a high-pass filter with a time constant equal to or less than the time constant of the averaging can be used. This removes the distortion of the MA component that was distorted by averaging. A band-reject filter can also be used by combining averaging 5301 and delay rejection 5302 to remove specific frequency components.

[0250] MA Synthesis 5303 either synthesizes multiple MA components generated above or selects one MA component. Synthesis may involve simply averaging multiple MA components. Alternatively, each MA component may be weighted before averaging. Selection may involve selecting MA components suitable for MA removal for each color, or selecting a single MA component common to all colors.

[0251] For example, a red signal often contains an MA component larger than the pulse wave component. The MA component obtained from the red signal can be used for removing the MA of the red signal and further for removing the MA of the green and near-infrared signals. When the ratio of the MA component to the pulse wave component is large, averaging 5301 and delay removal 5302 can be omitted and used for removing the MA of other colors. The synthesis and selection of MA synthesis 5303 may be sequentially changed for each context such as exercise, diet, conversation, etc.

[0252] MA detection 5304 detects the amplitude of the MA. The shape of the MA may be detected by a correlator or the like. Here, the magnitude of the MA component of each color is grasped. The magnification learner 5305 learns the magnitude of the detected MA component for a certain period. A moving average or the like may be used. The multiplier 5306 multiplies the MA component synthesized in MA synthesis 5303 by a magnification corresponding to the magnitude of the learned MA component. For example, when the shapes of the MA components of red, near-infrared, and green are substantially the same and the ratio of magnitudes is 5:2:1, the red MA component can be selected as the MA synthesis waveform, and 2 / 5 and 1 / 5 can be selected as the magnifications of the near-infrared and green magnification learners 5305, respectively.

[0253] The subtractor 5307 subtracts the MA components of each color generated above from the raw waveform of each color. The filter 5308 filters the waveform from which the MA component has been subtracted. These preprocessings 3502 can cut out the signals arriving in real time into segments of about several tens of seconds and process them.

Example

[0254] This example is an example related to the post-processing block 3503 in FIG. 35 in the fourth embodiment. It will be described below using FIG. 54. These post-processings 3503 can cut out the signals arriving in real time into segments of about several tens of seconds and process them.

[0255] Green, red, and near-infrared signals can be used as input. Noise extraction 5401 extracts noise components that could not be removed in preprocessing. The noise component N is calculated, for example, using equation 8. Here, X is the RMS value of each input signal, and S is the RMS value of the signal obtained by amplitude calculation 5408, which will be described later. SNR calculation 5402 is calculated from the signal S and N obtained by noise extraction 5401 using equation 9.

[0256]

number

[0257]

number

[0258] The phase adjustment 5403 detects and adjusts the phase difference between each color. For example, the configuration shown in Figure 55 can be used as the phase adjustment 5403. In Figure 55, the amplitude normalizer 5501 normalizes the amplitude of each color to, for example, 1. The multiplier 5502 multiplies the phase reference signal by the signals of each color. The integrator 5503 integrates the multiplied signal over a certain period of time. The integrated value is normalized by dividing it by the frequency within the integration period as appropriate. The frequency within the integration period can be obtained by squaring the reference signal and integrating it.

[0259] If α is the phase of the reference signal and β is the phase of the signal whose phase we want to find, then the multiplication of the two signals is given by equation 10. The integrator 5503 outputs a value in the range of +0.5 to -0.5 depending on the phase difference. Normally, the phase difference is small, so it takes a value close to +0.5. The ΔΦ output 5504 is the output of this phase difference. Incidentally, the second term on the right side of equation 10 is double the frequency and is removed by integration. The Δt adjustment 5505 calculates the time delay Δt for each color from the calculated phase difference and the frequency within the above integration period.

[0260]

number

[0261] The phases of signals can be aligned by shifting the time axis of signals with a phase delay by Δt. For example, if the green and red signals have a delay relative to the near-infrared signal, the above process is performed using the near-infrared signal as the phase reference to determine the Δt for each of the green and red signals. By shifting the time axis of the green and red signals by their respective Δt values, the phases of each signal can be aligned.

[0262] The multiplier 5404 in Figure 54 multiplies the signal by the SNR for each color. Phase-adjusted signals are used as the signals. The adder 5405 adds the results of the multiplication by the multiplier 5404. This allows for the synthesis of signals weighted by the SNR.

[0263] Signal extraction 5406 uses the synthesized signal to detect peak positions. Several methods can be used to detect peak positions, as described above, but for example, in time-domain processing, a method can be used that dynamically changes the threshold while taking a moving average of the signal amplitude.

[0264] Synchronous summation 5407 performs synchronous summation for each color using the detected peak position and the phase-adjusted signal. For example, it resamples the time-series data for one period from one peak to the next into about 100 data points, repeats this for the next period, adds the 100 data points together, and divides by 2. This can also be done for N periods of data using a moving average. Amplitude calculation 5408 calculates, for example, the RMS value of one period after synchronous summation. This allows obtaining a signal amplitude with attenuated noise. The obtained signal amplitude is used for noise extraction 5401.

[0265] Green signals have a smaller MA and higher SNR compared to red and near-infrared signals. However, in some locations, the amplitude is small and may be buried in noise other than MA, so it is often easier to detect peaks by combining them with the amplitudes of other colors, such as near-infrared signals. For signals other than green signals, the SNR drops sharply when MA occurs, so the above-mentioned SNR-dependent combining method is effective. If the phases are not aligned during combining, errors will occur in the calculation of heart rate variability (PRV) and SpO2, etc.

[0266] Adaptively changing the color signal used depending on the SNR and purpose also leads to power savings. For example, a relatively large pulse wave can be obtained with a small LED current using a near-infrared signal. In normal PRV measurements, only the near-infrared signal is turned on, and the green LED is turned on when the MA becomes large. Such switching can only be performed accurately by incorporating phase adjustment. SpO2 is usually measured using only the red and near-infrared signals, but by using a phase-adjusted green signal in combination when the MA is large, robust and accurate measurements can be performed.

[0267] Green and red signals may have a delayed peak position relative to near-infrared signals. Near-infrared signals penetrate deep into the skin and detect pulse waves from relatively large arteries, while green and red signals detect pulse waves from relatively shallow areas. There are reports that this reflects the delay from large to small arteries. Experiments by the inventors have also observed that green and red signals lag behind near-infrared signals. They have also found that the amount of delay changes over time. This can be used to extract autonomic nerve signals and context from the phase difference ΔΦ output 5504 of the phase adjustment 5403. [Examples]

[0268] This embodiment relates to the SpO2 extraction means 4007 shown in Figure 40 of the fourth embodiment. Robustness to MA has been improved. This will be explained below with reference to Figure 56(a).

[0269] The inputs can be a red signal, a near-infrared signal, a template signal, and a peak position. The red signal and near-infrared signal often have large MAs, and filtering them will cause large vibrations and distortions when MAs are generated. Therefore, here we use unfiltered signals for the red signal and near-infrared signal. As a template signal, for example, the output of adder 5405 in Example 17, i.e., a signal obtained by combining multiple color signals after passing through preprocessing such as filtering, can be used.

[0270] The DC removal unit 5601 removes the DC component from the red signal and near-infrared signal by averaging or other means. The obtained DC component can also be used in equation 2 (5604). The multiplier 5602 multiplies the red signal with the DC removed by the template, and the near-infrared signal with the DC removed by the template. The integrator 5603 integrates the red signal multiplied by the template, and integrates the near-infrared signal multiplied by the template. The results of this integration are AC1 and AC2 in equation 2, from which R can be obtained from equation 2 (5604) and SpO2 from equation 3 (5605). The above processing can be performed on a single pulse wave, from one peak to the next, based on the peak position.

[0271] Figure 56(b) shows the operation of Figure 56(a). The following processing is performed on the red light and the near-infrared signal, respectively. For example, when processing the red light, the data is the data before filtering. The following processing is performed on the interval from one peak to the next. The average within the interval is taken and subtracted to remove the DC component (5606). The template signal has already had the DC component removed in preprocessing 3502. The DC-removed red light and the template signal are multiplied within the interval (5607). The multiplication result is integrated within the interval (5608). The end of the interval is used as AC1 in equation 2 (5604) as the integral result. The near-infrared signal is processed similarly and used as AC2.

[0272] The above process is a cosine function process from peak to peak, and the noise in the sine function component is removed. For example, noise with a slope from one peak to the next is removed. When MA is applied, there may be cases where the signal is in a long slope or in a respiratory long period, and such disturbances are removed. The integration functions as a low-pass filter with a cutoff of 1 / (2τ) where the integration time is τ, and high-frequency noise present in the raw waveform is removed. [Examples]

[0273] This embodiment is an example relating to the context extraction means 4012 (Figure 40) in the fourth embodiment. This embodiment uses MA to recognize the wearer's context. This will be explained below with reference to Figure 57(a). The processing of these context extraction means 4012 can extract incoming signals in real time into segments of about several tens of seconds and process them.

[0274] Green, red, near-infrared, and template signals can be used as inputs. Unfiltered signals are used for the green, red, and near-infrared signals. For the template signal, for example, a MA for a specific context that has been extracted in advance can be used.

[0275] DC removal unit 5701 removes the DC component from the green, red, and near-infrared signals. Multiplier 5702 multiplies these signals, from which the DC has been removed, by the template. Integrator 5703 integrates the multiplication results over a certain range within the segment and moves that range within the segment. Amplitude extraction unit 5704 extracts the maximum or minimum value of this integration result within the segment as the amplitude for each color. Determinator 5705 determines that a context exists if the extracted amplitude is greater than or equal to a predetermined amplitude.

[0276] Figure 57(b) shows the MA waveform acquired when drinking water, using the biosignal measurement device according to the present invention attached to the temporal region. Although the shape, amplitude, and color signal ratios differ depending on vocalization, speech, and chewing, a reproducible waveform can be obtained. As mentioned above, swallowing, chewing, tongue movements, and vocalization affect the reflection of light beneath the temporal skin, generating MA. When actively extracting MA, as mentioned above, MA can be reproduced with a certain degree of reproducibility by selecting the location. The ratios of red, near-infrared, and green in Figure 57(b) are also reproduced, so ratios in addition to amplitude can be used for judgment by the judgment device 5705. Different wavelengths of light enter the body and reflect at different depths, and by using light of multiple wavelengths, MA information in the depth direction can be obtained. It can be used for measurement such as speech recognition, chewing count, chewing force, mealtime, forgetting to take medication, smile detection, and emotion detection. [Explanation of Symbols]

[0277] 100 Biosignal Measurement Devices 101 Optical Transceiver Unit 102a Cavity or groove 102 Stress transmission section 103 Communications Department 104 Power supply section 201 Outer shell structure 301 First external structure or eyeglasses, belt 302 Stress 303 Reaction force

Claims

1. A biosignal measurement device that is attached to the surface of a living organism, An optical transmitting and receiving unit (101) consisting of at least one set of optical transmitters and optical receivers arranged on the first surface of the biological surface, An external structure (301) consisting of the part of the glasses that passes through the region surrounded by the back of the ear and the temporal region of the living body, With respect to the first surface, the direction perpendicular to the outside of the living body is defined as "up," and there is a cavity (102a) located directly above the optical transmitting / receiving unit that is movable and fixed to the external structure, and a stress transmission unit (102) is located at the bottom surface of the cavity that transmits stress (302) applied from the external structure to the optical transmitting / receiving unit, A communication unit (103) that transmits the received signal from the optical receiver to another communication unit, A power supply unit (104) that supplies power to the optical transceiver unit and the communication unit, An outer shell structure (201) having at least three surfaces that house the optical transmitting / receiving unit, the communication unit, and the power supply unit, and together with the optical transmitting / receiving unit, transmit the stress to the biological surface in a region surrounded by the back of the ear and the temporal region, A biosignal measurement device characterized by having the following features.

2. An optical transmission and reception means comprising at least one set of optical transmission means and optical reception means for measuring biological information by the exchange of light with a living organism, An outer shell structure having at least three surfaces and housing the aforementioned optical transmitting and receiving means, An external structure consisting of a part of eyeglasses that passes through the region surrounded by the back of the ear and the temporal region of the living organism, The external structure has a cavity that provides movable fixation and is equipped with a stress transmission means that transmits stress from the external structure to the optical transmitting and receiving means, The stress transmission means is moved in the portion of the eyeglasses that constitutes the region surrounded by the back of the ear and the side of the head. The outer shell structure is brought into contact with the skin in the area surrounded by the back of the ear and the temporal region. Methods for measuring biological signals.

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