JP6482440B2 - Measuring apparatus and measuring system - Google Patents

Description

  The present invention relates to a measuring apparatus and a measuring system for measuring biological information.

  Conventionally, a measuring device for measuring biological information from a test site such as a wrist of a test subject is known. For example, in Patent Document 1, a pulse wave velocity (PWV) (pulse wave velocity (PWV)) is measured by attaching a pulse wave sensor to the subject's upper arm and knee and detecting each pulse wave. A wave propagation velocity measuring device is disclosed.

JP-A-2005-329122

  However, the measuring apparatus as described in Patent Document 1 requires a relatively large configuration.

  The objective of this invention made | formed in view of this viewpoint is providing the measuring apparatus and measuring system which can measure biological information accurately with a small-sized structure.

In order to solve the above problems, a measuring apparatus according to the present invention includes:
A wearing part to be worn by the subject;
A first sensor unit and a second sensor unit supported by the mounting unit and having a light emitting unit and a light receiving unit, respectively,
The first sensor unit and the second sensor unit are configured so that when the biological information of the subject is acquired, the first sensor unit and the second sensor unit are configured so that the predetermined part of the subject is in a state where the mounting unit is attached to the subject. Arranged at predetermined intervals along the blood vessels of
In the first sensor unit, at least one of an optical axis of light emitted from the light emitting unit and an optical axis of light incident on the light receiving unit is configured to be inclined toward the second sensor unit.

  Further, at least one of the optical axis of the light emitted from the light emitting unit and the optical axis of the light incident on the light receiving unit in the second sensor unit is configured to be inclined toward the first sensor unit side. May be.

Also,
The light emitting unit includes a light emitting element,
The light receiving unit includes a light receiving element,
At least one of the light emitting element and the light receiving element may be arranged to be inclined.

Also,
The light emitting unit includes a light emitting element,
The light receiving unit includes a light receiving element,
At least one of the direction of light emitted from the light emitting element and the direction of light incident on the light receiving element may be changed.

  Further, the distance between the light emitting unit in the first sensor unit and the light emitting unit in the second sensor unit is such that the light receiving unit in the first sensor unit and the light receiving unit in the second sensor unit are It may be shorter than the interval.

  The light emitting unit may be disposed on both sides of the light receiving unit along a direction perpendicular to a predetermined blood vessel of the subject.

  The light receiving unit may include an opening having a predetermined diameter.

  Further, the mounting portion may be a band that is mounted on the wrist of the subject.

  The biological information may be a pulse wave.

  Moreover, you may provide the control part which calculates a pulse wave propagation speed based on the said acquired pulse wave.

In order to solve the above problems, a measurement system according to the present invention includes:
A measuring device as described above;
And a display unit for displaying information based on the biological information acquired by the measuring device.

  According to the present invention, it is possible to provide a measuring apparatus and a measuring system that can accurately measure biological information with a small-scale configuration.

It is a perspective view which shows the external appearance of the measuring apparatus which concerns on one Embodiment of this invention. It is a schematic diagram which shows a part of measuring apparatus which concerns on one Embodiment of this invention, and its arrangement | positioning. It is the schematic diagram which showed the time change of the output voltage output from two light receiving elements in an ideal state. It is a mimetic diagram showing typical blood flow near a subject's wrist. It is the schematic diagram which showed the time change of the output voltage output from two light receiving elements in a typical state of an artery. It is the schematic diagram which showed arrangement | positioning of the light emission part of the measuring apparatus which concerns on the 1st Embodiment of this invention. It is the schematic diagram which showed arrangement | positioning of the light emission part of the measuring apparatus which concerns on the 2nd Embodiment of this invention. It is a schematic diagram which shows arrangement | positioning of the sensor part of the measuring apparatus which concerns on the 3rd and 1st embodiment of this invention. It is the schematic diagram which showed the package of the light receiving element of the measuring apparatus which concerns on the 4th Embodiment of this invention, and its arrangement | positioning. It is the schematic diagram which showed the structure of the light receiving / emitting element of the measuring apparatus which concerns on the 5th Embodiment of this invention. It is the schematic diagram which showed the mode of arrangement | positioning in the test site | part of each light receiving / emitting element of the measuring apparatus which concerns on the 5th Embodiment of this invention. It is a schematic diagram which shows arrangement | positioning of the sensor part of the measuring apparatus which concerns on the 6th Embodiment of this invention. It is a mimetic diagram showing a measuring system containing a measuring device concerning an embodiment of the present invention.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic perspective view showing a schematic configuration of a measuring apparatus 100 according to an embodiment of the present invention. As shown in FIG. 1, the measuring apparatus 100 includes a mounting part 110 and sensor parts 120a and 120b. As shown in FIG. 1, the mounting portion 110 has a back surface 111 facing the negative Z-axis direction and a front surface 112 facing the positive Z-axis direction shown in the drawing. The measuring apparatus 100 is used by being mounted in a state where the back surface 111 side of the mounting unit 110 faces the test site of the subject's living body. For this reason, when the subject wears the mounting portion 110 of the measuring apparatus 100, the subject can see the surface 112 of the mounting portion 110.

  The mounting part 110 of the measuring apparatus 100 has openings 113a and 113b on the back surface 111 side. The measuring apparatus 100 has a structure in which the sensor part 120a protrudes from the opening 113a and the sensor part 120b protrudes from the opening 113b.

  Since the mounting unit 110 is used while being mounted on the subject, it is preferable to have members such as band units 114 and 115, for example. In FIG. 1, as an example, band portions 114 and 115 used by being wound around the subject's arm or the like are shown halfway by broken lines. The band portions 114 and 115 are not limited to the configuration shown in FIG. 1 and may have any configuration that can be worn by the subject. In the present embodiment, the wearing unit 110 may be a band that is worn on the wrist of the subject including the band units 114 and 115.

  The measuring device 100 measures the biological information of the subject while the subject is wearing the measuring device 100. The biological information measured by the measuring apparatus 100 can be any biological information that can be measured by the sensor units 120a and 120b. Hereinafter, as an example, the measurement apparatus 100 will be described assuming that PWV is measured by acquiring two pulse waves of the subject.

  Further, in the present embodiment, the mounting portion 110 can be an elongated band-like band including the band portions 114 and 115. The measurement of biological information is performed, for example, in a state where the subject wraps the mounting unit 110 of the measuring apparatus 100 around the wrist. Specifically, the subject wraps the mounting unit 110 around the wrist so that the sensor units 120a and 120b are in contact with the test site, and measures biological information. The measuring device 100 measures the PWV of blood flowing through the ulnar artery or radial artery at the subject's wrist.

  FIG. 2A is a side view schematically showing a part of the measuring apparatus 100 according to one embodiment of the present invention. FIG. 2A shows a side view of the measuring apparatus 100 when viewed in the positive direction of the X axis shown in FIG. FIG. 2B is a schematic diagram showing the arrangement of the sensor units 120a and 120b of the measuring apparatus 100 according to an embodiment of the present invention. FIG. 2B shows only the sensor units 120a and 120b of the measuring apparatus 100 when viewed in the negative direction of the Z axis shown in FIG. Note that the XYZ coordinate system shown in FIGS. 2A and 2B is the same as that in FIG. 1, and the same applies to the subsequent drawings.

  As shown in FIG. 2A, the sensor units 120 a and 120 b are supported by the mounting unit 110. The measuring apparatus 100 has a structure in which the sensor units 120a and 120b protrude from the back surface 111 side of the mounting unit 110 in the negative Z-axis direction.

  The sensor units 120a and 120b include biological sensors that acquire biological information of the subject. The sensor units 120a and 120b measure the biological information of the subject while being in contact with the test site of the subject.

As will be described later, the sensor unit 120a and the sensor unit 120b are arranged along the predetermined blood vessels of the subject when the mounting unit 110 is mounted on the subject when acquiring the biological information of the subject. Arranged. At that time, the distance [Delta] D ₁ between the sensor portion 120a and the sensor section 120b are arranged to be equal to or less than 35 mm. In addition, as shown in FIG. 2B, each sensor unit is arranged vertically (X-axis direction) with respect to the artery through which blood flows in the positive Y-axis direction. Each of the sensor units 120a and 120b acquires pulse waves at different test sites by an optical method. Here, the pulse wave is a part of biological information obtained by capturing a change in volume of a blood vessel caused by the inflow of blood as a waveform from the body surface. In one embodiment of the present invention, the sensor units 120a and 120b optically acquire pulse waves that are biological information. Further, based on the acquired pulse wave, the control unit of the measuring apparatus 100 calculates PWV. In FIG. 2B, the sensor unit 120a is arranged on the upstream side of the artery and the sensor unit 120b is arranged on the downstream side. However, the arrangement is not limited to this. It is good.

  As shown in FIG. 2B, the sensor unit 120a includes two light emitting units 121a and 122a and a light receiving unit 123a. Similarly, the sensor unit 120b includes two light emitting units 121b and 122b and a light receiving unit 123b. As shown in FIG. 2B, the sensor units 120a and 120b are arranged at a predetermined interval along the X axis. In the sensor unit 120a, the light emitting / receiving units are arranged in the order of the light emitting unit 121a, the light receiving unit 123a, and the light emitting unit 122a so as to cross the artery and go in the positive X-axis direction. Similarly, in the sensor unit 120b, each light emitting / receiving unit is arranged in the order of the light emitting unit 121b, the light receiving unit 123b, and the light emitting unit 122b so as to cross the artery and go in the positive X-axis direction. That is, the light emitting units are arranged at predetermined intervals on both sides of the corresponding light receiving units along a direction perpendicular to the predetermined blood vessel of the subject (X-axis direction).

  2A and 2B, the light emitting units 121a, 122a, 121b, and 122b include light emitting elements 124a, 125a, 124b, and 125b, respectively, and the light receiving units 123a and 123b are light receiving elements 126a and 126b. Respectively. The light emitted from each light emitting element propagates to the outside of the light emitting unit and passes through the living body from the test site. At that time, the light scattered inside the living body is detected by each light receiving element. The pulse wave is acquired according to the detected scattered light intensity. As the light emitting element, for example, an element such as an LED (Light Emitting Diode), an LD (Laser Diode), or an SLD (Superluminescent Diode) can be applied. In addition, as the light receiving element, for example, an element such as PD (Photodiode) or PT (Phototransistor: Phototransistor) can be applied. In FIG. 2B, one light emitting / receiving element is shown for each light emitting / receiving unit; however, the present invention is not limited to this, and the number of light receiving / emitting elements included in each light receiving / emitting unit may be plural. Good.

  In the above configuration, each sensor unit has been described as having two light emitting units and one light receiving unit. However, in one embodiment of the present invention, each sensor unit includes one light emitting unit and two light receiving units. Measurement can also be performed by a configuration having a light receiving section. Each sensor unit can also perform measurement by a configuration having one light emitting unit and one light receiving unit. Hereinafter, a configuration having two light emitting units and one light receiving unit will be described.

  The light emitting units 121a, 122a and 121b, 122b emit, for example, one of green light (wavelength: 500 to 550 nm), red light (wavelength: 630 to 780 nm), and near infrared light (wavelength: 800 to 1600 nm). Since long-wavelength light is not attenuated to a deeper position in the body than short-wavelength light, measurement of biological information using a near-infrared light-emitting element improves measurement accuracy.

  Based on the two acquired pulse waves, the principle of measuring PWV between close distances on the wrist will be described with reference to FIGS. FIG. 3A is a schematic diagram showing an ideal state where the artery is in a straight line between the two sensor units 120a and 120b, and the distance from the skin A1 does not change in the living body inside A2. FIG. 3B is a schematic diagram showing a time change of the output voltage output from the light receiving elements 126a and 126b included in the light receiving portions 123a and 123b in the sensor portions 120a and 120b in the state shown in FIG. 3A. FIG. FIG. 3A shows only the light emitting unit 121a of the sensor unit 120a and the light emitting unit 121b of the sensor unit 120b among the light receiving and emitting units in the sensor units 120a and 120b. The light emitting units 121a and 121b include light emitting elements 124a and 124b, respectively. In the embodiment of the present invention, each light emitting element is an LED and each light receiving element is a PD.

  As shown in FIG. 3A, the light emitting units 121a and 121b come into contact with the skin A1 on the wrist surface represented by a solid line when measuring biological information. The light emitted from the light emitting elements 124a and 124b is isotropically greatly spread, enters the living body inside A2 from the skin A1, and reaches the artery for measuring the pulse wave. In the artery, blood flows from the left to the right (Y-axis positive direction), and thus the pulse wave also propagates in the same direction. At this time, the light emitted from the light emitting elements 124a and 124b reaching the artery is scattered, and the intensity of the scattered light changes according to the change in the volumetric time of the blood vessel. The scattered light is detected by the light receiving elements 126a and 126b included in the light receiving portions 123a and 123b, and a pulse wave is acquired by outputting a voltage. In FIG. 3A, the light receiving portions 123a and 123b have the same positions in the Y and Z axis directions as the light emitting portions 121a and 121b, and only the positions in the X axis direction are different.

  FIG. 3B shows a pulse wave waveform obtained in an ideal state as shown in FIG. The pulse wave a indicates a time change of the voltage output from the light receiving element 126a on the sensor unit 120a side having the light emitting unit 121a. The pulse wave b indicates a time change of the voltage output from the light receiving element 126b on the sensor unit 120b side having the light emitting unit 121b. In FIG. 3B, the respective waveforms are compared one above the other.

Since the sensor unit 120a is arranged on the upstream side of the artery and the sensor unit 120b is arranged on the downstream side of the artery, the rise of the peak of the pulse wave a is earlier by Δt ₁ than the rise of the peak of the pulse wave b. Become. PWV (m / sec) is obtained by dividing the interval ΔD ₁ between the sensor unit 120a and the sensor unit 120b by Δt ₁ . Thus, assuming an ideal state where the artery is straight, the pulse wave a and the pulse wave b have the same waveform, and the phase difference at an arbitrary point is also constant.

  By the way, an actual blood vessel is not in an ideal state as shown in FIG. Hereinafter, description will be made assuming that biological information is measured from an actual blood vessel. First, the actual state of blood vessels will be described with reference to FIG. FIG. 4 is a diagram schematically showing a state in which typical bones and blood vessels near the right wrist of a general subject are seen through from the palm of the hand. There are two bones, an ulna and a radius, on the right wrist of a general subject. Furthermore, two arteries, the ulnar artery V1 and the radial artery V2, pass through the inside of the living body so as to follow the ulna and the radius. In each artery, blood flows in the direction of the arrow shown in FIG.

  Here, as shown in FIG. 4, the ulnar artery V <b> 1 is arranged along the terminal portion of the ulna in the region R <b> 1 where the terminal end of the ulna exists. In the region R2 where the ulnar artery V1 is not disposed on the ulna, the ulnar artery V1 enters the living body. For this reason, the ulnar artery V1 dives deeper from the skin surface into the living body in the vicinity of the wrist in the regions R1 and R2 shown in FIG. That is, on the downstream side of the ulnar artery V1 viewed from the region R1 and the upstream side of the ulnar artery V1 viewed from the region R2, the distance from the skin to the ulnar artery V1 is longer. In contrast, in the region sandwiched between the regions R1 and R2, the ulnar artery V1 is disposed on the ulna, and the ulnar artery V1 passes between the ulna and the skin. Becomes shallower. In the region sandwiched between the regions R1 and R2, the distance from the skin to the ulnar artery V1 becomes shorter and becomes substantially constant.

  Similarly, as shown in FIG. 4, in the region R3 where the end of the radius exists, the radial artery V2 is arranged along the end of the radius. In the region R4 where the radial artery V2 is not disposed on the radius, the radial artery V2 enters the living body. For this reason, radial artery V2 dives deeper from the skin surface to the inside of the living body near the wrist in regions R3 and R4 shown in FIG. That is, the distance from the skin to the radial artery V2 is longer on the downstream side of the radial artery V2 viewed from the region R3 and the upstream side of the radial artery V2 viewed from the region R4. On the contrary, in the region sandwiched between the regions R3 and R4, the radial artery V2 is arranged on the radius, and the radial artery V2 passes between the radius and the skin, so the depth of the radial artery V2 inside the living body. Becomes shallower. In the region sandwiched between the regions R3 and R4, the distance from the skin to the radial artery V2 becomes shorter and becomes substantially constant.

  When measuring biological information from a blood vessel, it is preferable that the site to be examined is a site where the distance from the skin to the blood vessel is short, that is, the depth of the blood vessel from the skin surface to the inside of the living body is shallow. In addition, as shown in FIG. 3A, a state where the distance from the skin to the blood vessel does not change inside the living body is ideal. By satisfying such a condition, the pulse wave can be measured with higher accuracy. Therefore, in this embodiment, the region to be examined is directly above the ulnar artery V1 in the region sandwiched between the regions R1 and R2 shown in FIG. 4 or the radial artery V2 in the region sandwiched between the regions R3 and R4. To.

  As a result of observing the waveform of the pulse wave output while changing the test site of the wrist variously, the lengths L1 and L2 of the ulnar artery V1 and radial artery V2 immediately below the optimal test site were 35 mm, respectively. It was. As a result of observation, the lengths L1 and L2 were found to be 35 mm on average although there were some individual differences in the arrangement of blood vessels. The region R1 where the end of the ulna exists can be confirmed from the outside as a protrusion (ulna protrusion) of the wrist. The region R3 where the end of the radius exists can be confirmed from the outside as a wrist protrusion (radius protrusion). The optimum range for measuring the pulse wave is a range of 35 mm from the ulnar protrusion to the upstream side of the ulnar artery. The optimum range for measuring the pulse wave is a range of 35 mm from the radial protrusion to the upstream side of the radial artery. The optimum range for measuring the pulse wave is a range where blood vessels are present on the skin side of the radius or the skin side of the ulna, respectively.

  FIG. 5A is a schematic diagram showing a state in which an artery is curved in the vicinity of the two sensor portions 120a and 120b, and the distance from the skin A1 is long (deep in the living body interior A2). FIG. 5A shows a cross section of a part inside the living body and the two sensor units 120a and 120b along the Y-axis direction of FIG. As described above, when the subject is a human, in many subjects, the ulnar artery or radial artery near the wrist typically has a cross-sectional shape as shown in FIG. FIG. 5B is a schematic diagram showing a time change of the output voltage output from the light receiving elements 126a and 126b included in the two light receiving portions 123a and 123b in the state shown in FIG. 5A. FIG. 5A shows only the light emitting unit 121a of the sensor unit 120a and the light emitting unit 121b of the sensor unit 120b among the respective light emitting / receiving units, as in FIG. 3A. The light emitting unit 121a and the light emitting unit 121b include light emitting elements 124a and 124b, respectively.

  As in the case of FIG. 3A, blood flows in the Y-axis positive direction in the artery, and therefore the pulse wave also propagates in the same direction. At this time, the light emitted from the light emitting elements 124a and 124b reaching the artery is scattered, and the intensity of the scattered light changes according to the change in the volumetric time of the blood vessel. The scattered light is detected by the light receiving elements 126a and 126b included in the light receiving portions 123a and 123b, and the pulse wave is measured by outputting a voltage. In FIG. 5A, the light receiving portions 123a and 123b have the same positions in the Y and Z axis directions as the light emitting portions 121a and 121b, but only the positions in the X axis direction.

  FIG. 5B shows the waveform of the pulse wave obtained in a typical state as shown in FIG. Pulse waves a and b show the waveform of the pulse wave obtained in the ideal state shown in FIG. 3B by dotted lines for comparison. A pulse wave a 'indicates a change with time of the voltage output from the light receiving element 126a on the sensor unit 120a side having the light emitting unit 121a. The pulse wave b 'indicates a change with time of the voltage output from the light receiving element 126b on the side of the sensor unit 120b having the light emitting unit 121b. In FIG. 5B, the respective waveforms are compared side by side.

  Since the light emitted from the light emitting elements 124a and 124b passes through the living body A2 from the skin A1 while spreading isotropically, the waveform output from each light receiving element is directly under the test site where the sensor units 120a and 120b are arranged. In addition to the blood vessel information, the upstream and downstream blood vessel information is also included. That is, in the situation shown in FIG. 5A, the output voltage from each light receiving element is not only the information on the pulse wave obtained from the straight part of the artery, but also the artery is curved upstream and downstream. It also includes information on the pulse wave obtained from the part.

  In such a situation, first, the pulse wave a 'and the pulse wave a are compared. Since the artery is curved upstream from the light emitting element 124a and the distance from the skin A1 is long, the distance from the curved part to the light receiving element 126a is also long. The longer the distance to the light receiving element 126a, the weaker the intensity of the scattered light that is detected. Accordingly, the rise of the peak of the pulse wave a 'becomes slower than the rise of the peak of the pulse wave a because the intensity of the scattered light is weakened. On the other hand, since the downstream artery viewed from the light emitting element 124a is linear as in the ideal state, the fall of the peak of the pulse wave a ′ is the same as the fall of the peak of the pulse wave a. become. In this manner, the phase of the pulse wave a 'is shifted in a direction that is delayed with respect to the phase of the pulse wave a by the amount that the rise of the peak is delayed.

  Subsequently, the pulse wave b and the pulse wave b 'are compared. Since the artery is curved downstream from the light emitting element 124b and the distance from the skin A1 is long, the distance from the curved part to the light receiving element 126b is also long. The longer the distance to the light receiving element 126b, the weaker the intensity of the scattered light that is detected. Accordingly, the fall of the peak of the pulse wave b 'is earlier than the fall of the peak of the pulse wave b because the intensity of the scattered light is weakened. On the other hand, since the upstream artery viewed from the light emitting element 124b is linear as in the ideal state, the rise of the peak of the pulse wave b 'is almost the same as the rise of the peak of the pulse wave b. Become. As described above, the phase of the pulse wave b 'is shifted in the direction of time advance compared to the phase of the pulse wave b by the amount that the peak falls earlier.

Here, the pulse wave a ′ and the pulse wave b ′ are compared. The phase of the pulse wave a ′ and the pulse wave b ′ are shifted in directions opposite to each other as compared with the pulse wave waveforms (pulse wave a and pulse wave b) obtained in an ideal state. The phase of the pulse wave a ′ shifts in a direction that is delayed in time, and the phase of the pulse wave b ′ shifts in a direction that advances in time. Also, the similarity of the waveforms of the two pulse waves a ′ and b ′ is easily lost. Thereby, in the ideal state, the rise of the peak of the upstream pulse wave “a” was earlier by Δt ₁ than the rise of the peak of the downstream pulse wave “b”. It is also assumed that the rise of the peak of the pulse wave a ′ is delayed by Δt ₂ compared to the rise of the peak of the downstream pulse wave b ′. As described above, in the actual measurement, when the interval ΔD ₁ between the two sensor units is not optimally adjusted, the peak of the pulse wave b ′ is detected earlier in time depending on the measurement position of the pulse wave with respect to the artery. The For this reason, a waveform as if the pulse wave is flowing backward from the right to the left (Y-axis negative direction) is obtained.

  Therefore, in the present invention, the reverse phenomenon of the phase difference between the sensor units 120a and 120b is eliminated. In the following, some solutions will be described based on some embodiments of the present invention. In each embodiment, a configuration different from the configuration described above will be mainly described. For convenience of explanation, components having the same functions as the components described above are denoted by the same reference numerals, and the description thereof is simplified or omitted as appropriate. In carrying out the present invention, only one of the following embodiments may be applied, or a plurality of different embodiments may be applied in appropriate combination.

(First embodiment)
FIG. 6 is a schematic diagram showing the arrangement of the sensor units 120a and 120b of the measuring apparatus 100 according to the first embodiment of the present invention. FIG. 6 representatively shows only the light emitting units 121a and 121b and the light emitting elements 124a and 124b among the components of the sensor units 120a and 120b.

In order to eliminate the reversal phenomenon of the phase difference between the sensor units 120a and 120b, in the measuring apparatus 100 according to the first embodiment of the present invention, as shown in FIG. 6, the distance between the sensor unit 120a and the sensor unit 120b. Is optimally adjusted. That is, the interval between the sensor unit 120a and the sensor unit 120b is newly defined as ΔD _{2 and} is smaller than the interval ΔD ₁ shown in FIG. 5A (ΔD ₂ <ΔD ₁ ). The sensor units 120a and 120b are arranged at positions where the light emitted from the light emitting elements 124a and 124b is difficult to reach the curved portion of the artery. Thereby, the phase shift of the pulse wave a ′ and the pulse wave b ′ as described in FIG. 5B does not occur, and the ideal pulse wave described in FIG. 3B can be acquired. . When the interval ΔD ₂ between the sensor unit 120a and the sensor unit 120b is increased, the phase difference between the pulse wave a ′ and the pulse wave b ′ becomes sufficiently large, and the measurement apparatus 100 can measure the pulse wave with higher accuracy. it can. However, if ΔD ₂ is increased too much, the sensor unit 120a and the sensor unit 120b are disposed immediately above the regions where the artery is curved and the distance from the skin A1 becomes longer (regions B1 and B2 shown in FIG. 5A). Will be. As a result, the intensity of the scattered light detected by the light receiving elements 126a and 126b becomes weak, and the pulse wave waveform is less likely to be output.

Under the condition that the waveform of the pulse wave can be detected, the interval ΔD ₂ between the sensor unit 120a and the sensor unit 120b has an upper limit value. As a result of observing the waveform of the pulse wave output while changing the test site of the wrist variously, it was found that the upper limit value of the interval between the sensor units 120a and 120b was 35 mm. That is, this value can be regarded as being equivalent to the lengths L1 and L2 of the ulnar artery V1 and radial artery V2 immediately below the optimal test site in FIG. Therefore, the sensor unit 120a and the sensor unit 120b are preferably configured so that, when acquiring the biological information of the subject, the predetermined blood vessels (the subject's blood vessels) are mounted in the state where the mounting unit 110 is mounted on the subject. For example, it is arranged at intervals of 35 mm or less along the ulnar artery or radial artery near the wrist of the subject. More specifically, the light emitting element 124a of the light emitting unit 121a in the sensor unit 120a and the light emitting element 124b of the light emitting unit 121b in the sensor unit 120b are arranged at intervals of 35 mm or less along a predetermined blood vessel of the subject. Configure as follows.

On the other hand, since the size of each sensor part 120a, 120b can be about 5 mm in width, in this embodiment, the lower limit value of ΔD ₂ is about 5 mm (the interval between the light emitting elements of the light emitting parts 121a, 121b). It can also be. However, when ΔD _{2 is set} to 5 mm, the phase difference between the output waveforms becomes small, and the output waveforms overlap each other. Therefore, under the condition that PWV can be measured appropriately, the lower limit of ΔD ₂ is 10 to 15 mm.

Thus, by adjusting ΔD ₂ more optimally between the lower limit value and the upper limit value, the above-described phase difference reversal phenomenon is eliminated. Thereby, the measuring apparatus 100 can measure biological information including PWV with high accuracy while reducing the configuration.

(Second Embodiment)
In the second embodiment of the present invention, as shown in FIG. 7, a lens unit is provided in the light emitting element of the light emitting unit to suppress the spread of light emitted from each light emitting element. FIG. 7 representatively shows only one light emitting unit 121a of the sensor unit 120a and one light emitting unit 121b of the sensor unit 120b, and includes light emitting elements 124a and 124b, respectively. In the present embodiment, a lens portion 134a is provided to suppress the spread of light emitted from the light emitting element 124a, and the lens portion 134b is provided to suppress the spread of light emitted from the light emitting element 124b. In addition, it is preferable to similarly provide a lens unit for each light emitting element included in the other light emitting unit 122a of the sensor unit 120a and the other light emitting unit 122b of the sensor unit 120b.

As shown in FIG. 7, in the present embodiment, a distance ΔD ₃ between the sensor unit 120a and the sensor unit 120b is defined. Similarly to the first embodiment of the present invention, ΔD ₃ is set to 35 mm or less. That is, the two sensor units 120a and 120b are arranged immediately above the straight part of the artery. In the artery, blood flows in the positive direction of the Y axis shown in the figure, and therefore the pulse wave also propagates in the same direction.

  At this time, since the light emitted from the light emitting elements 124a and 124b is collected by the lens portions 134a and 134b, the spread of the emitted light inside the living body A2 is suppressed. The region where the light incident on the inside A2 of the living body is scattered is narrower than when light is emitted over a wide range without providing the lens portions 134a and 134b. In other words, the light incident on the inside A2 of the living body reaches only the straight part of the artery and is scattered only by the straight part. That is, in this embodiment, the output voltage from each light receiving element includes only information on the pulse wave obtained from the straight part of the artery, and includes information on the pulse wave obtained from the curved part located upstream and downstream thereof. Absent.

  As described above, in the second embodiment of the present invention, information on the pulse wave from the curved portion of the artery that causes the phase inversion phenomenon as described above is not included. For this reason, in this embodiment, the measuring apparatus 100 can improve the precision of the measurement of a pulse wave. In this embodiment, the light emitted from the light emitting elements 124a and 124b is effectively used by providing the lens portions 134a and 134b on the light emitting elements 124a and 124b. That is, in this embodiment, the measuring apparatus 100 can prevent light from entering in a direction unrelated to the arterial direction and can perform measurement efficiently.

(Third embodiment)
FIG. 8A is a schematic diagram showing the arrangement of the sensor units 120a and 120b of the measuring apparatus 100 according to the third embodiment of the present invention. FIG. 8B is a diagram schematically showing again the arrangement of the sensor units 120a and 120b of the measuring apparatus 100 according to the first embodiment of the present invention for comparison with FIG. 8A. is there. 8A and 8B, an interval ΔD ₄ between the sensor unit 120a and the sensor unit 120b is defined. As described above, ΔD ₄ is set to 35 mm or less. That is, the two sensor units 120a and 120b are arranged immediately above the straight part of the artery. As shown in FIGS. 8A and 8B, in the artery, blood flows in the positive Y-axis direction, and thus the pulse wave also propagates in the same direction.

  In the third embodiment of the present invention, as shown in FIG. 8A, the interval between the light emitting units 121a and 122a in the sensor unit 120a and the light emitting units 121b and 122b in the sensor unit 120b is the light receiving unit in the sensor unit 120a. It is shorter than the interval between 123a and the light receiving portion 123b in the sensor portion 120b. Further, as in the second embodiment, each light emitting element is provided with a lens portion so as to suppress the spread of light emitted from each light emitting element. In FIG. 8A, illustration of light receiving and emitting elements in each light receiving and emitting unit is omitted. In the first embodiment described above, as shown in FIG. 8B, the light emitted from each light emitting element spreads isotropically. On the other hand, in the third embodiment, as shown in FIG. 8A, the light emitted from each light emitting element is given directivity. In order to realize this directivity, in the third embodiment, the optical axis of light emitted from each light emitting element of the light emitting units 121a and 122a in the sensor unit 120a is inclined to the light receiving unit 123a side through the lens unit. Yes. Similarly, the optical axis of the light emitted from each light emitting element of the light emitting units 121b and 122b in the sensor unit 120b is inclined to the light receiving unit 123b side through the lens unit. That is, in the third embodiment, the direction of light emitted from each light emitting element changes before and after passing through the lens unit. Similarly, each light receiving element may be provided with a lens portion. In this case, the direction of light incident on each light receiving element changes before and after passing through the lens unit.

  In the third embodiment, the upstream blood vessel information viewed from the sensor unit 120a and the downstream blood vessel information viewed from the sensor unit 120b are included in the scattered light detected by the light receiving elements of the light receiving units 123a and 123b. Absent. That is, in the third embodiment, since the information on the pulse wave obtained from the curved portion of the artery is not included in the measurement result, the similarity of the waveform of the pulse wave output from each light receiving element of the sensor units 120a and 120b is And reversal of the phase difference is avoided. In the third embodiment, the light output received by each light receiving element is increased by tilting the optical axis of the light emitted from each light emitting unit toward the corresponding light receiving unit 123a, 123b via the lens unit. . Furthermore, in the third embodiment, since the optical axis of the light emitted from each light emitting element is inclined toward the light receiving element in the same sensor unit, the light emitted from the light emitting element in one sensor unit is reflected in the other sensor unit. Prevents light from entering the light receiving element. Thereby, the measuring apparatus 100 can measure the pulse wave with high accuracy.

(Fourth embodiment)
FIG. 9A is a schematic view showing a package of the light receiving element 126a of the measuring apparatus 100 according to the fourth embodiment of the present invention. FIG. 9B is a schematic diagram showing a state when the light receiving portions 123a and 123b of the measuring apparatus 100 according to the present embodiment are arranged along the artery. In FIG. 9B, illustration of the two light emitting units of each sensor unit is omitted.

  As shown in FIG. 9A, the light receiving portion 123a includes a light receiving element 126a. In this embodiment, as shown in FIG. 9A, the light receiving element 126a is surrounded by a light shielding plate 150a including an opening 140a having a predetermined diameter. The opening 140a is provided immediately above the light receiving element 126a so that the light receiving element 126a can detect a part of the light scattered by the artery. Note that the same configuration as described above can also be applied to the light receiving unit 123b.

  As shown in FIG. 9B, in the artery, blood flows in the positive direction of the Y axis, and therefore the pulse wave also propagates in the same direction. In the present embodiment, the light shielding plates 150a and 150b are provided to eliminate scattered light including information on unwanted pulse waves. That is, the light scattered by the curved portion of the artery on the upstream side viewed from the light receiving unit 123a and the downstream side viewed from the light receiving unit 123b is blocked by the light shielding plates 150a and 150b from entering the light receiving elements 126a and 126b. Therefore, the light incident from the openings 140a and 140b and detected by the light receiving elements 126a and 126b is limited to the light scattered by the straight part of the artery.

  As described above, in the fourth embodiment, since the information on the pulse wave obtained from the curved portion of the artery is excluded by the light shielding plates 150a and 150b, the pulse wave output from the light receiving elements 126a and 126b of the sensor units 120a and 120b. The waveform similarity is improved and the reversal of the phase difference is avoided. In addition, the area of the light receiving portion is expanded by arranging the light receiving portions 123a and 123b so as to extend in the direction perpendicular to the artery (X-axis direction). Thereby, not only the output voltage output from the light receiving elements 126a and 126b is improved, but also the tolerance of the installation position with respect to the test site is improved.

(Fifth embodiment)
FIG. 10A is a schematic view showing a light emitting element 124a of the measuring apparatus 100 according to the fifth embodiment of the present invention. FIG. 10B is a schematic diagram showing the light receiving element 126a of the measuring apparatus 100 according to the fifth embodiment of the present invention.

  In the fifth embodiment of the present invention, at least one of the light emitting elements and the light receiving elements of the sensor units 120a and 120b is inclined toward the other sensor unit. Preferably, three patterns are conceivable. That is, in the first pattern, the measuring apparatus 100 is configured such that the two light emitting elements and one light receiving element of the sensor unit 120a and the two light emitting elements and one light receiving element of the sensor unit 120b are all on the other sensor unit side. It is comprised so that it may incline. In the second pattern, the measuring apparatus 100 is configured such that only the two light emitting elements of the sensor unit 120a and the two light emitting elements of the sensor unit 120b are inclined toward the other sensor unit. In the third pattern, the measuring apparatus 100 is configured such that only one light receiving element of the sensor unit 120a and one light receiving element of the sensor unit 120b are inclined toward the other sensor unit.

  FIG. 10A shows a state in which the light emitting element 124a included in the light emitting unit 121a of the sensor unit 120a is inclined toward the sensor unit 120b as an example. In FIG. 10A, description will be made assuming that the other sensor unit 120b is arranged on the right side of the light emitting unit 121a. By tilting the light emitting element 124a, the optical axis of the light emitted from the light emitting element 124a is tilted toward the sensor unit 120b. Here, the optical axis is perpendicular to the emission surface of the light emitting element 124a. Similarly, FIG. 10B illustrates a state where the light receiving element 126a included in the light receiving unit 123a of the sensor unit 120a is inclined toward the sensor unit 120b as an example. Also in FIG. 10B, description will be made assuming that the other sensor unit 120b is arranged on the right side of the light receiving unit 123a. By tilting the light receiving element 126a, the optical axis of the light incident on the light receiving element 126a is tilted toward the sensor unit 120b. Here, the optical axis is perpendicular to the incident surface of the light receiving element 126a. As in the fourth embodiment, in this embodiment as well, it is preferable that the light receiving element 126a is surrounded by a light shielding plate 150a including an opening 140a having a predetermined diameter. However, in the present embodiment, unlike the fourth embodiment, the light receiving element 126a is not disposed directly below the opening 140a, but is disposed slightly closer to the light shielding plate 150a side.

  As described above, the inclined portion is preferably the light receiving / emitting element included in each light emitting / receiving unit, and is preferably not tilted. Each light emitting / receiving unit is arranged at predetermined intervals along a predetermined blood vessel of the subject when the mounting unit 110 is mounted on the subject when acquiring the biological information of the subject. At this time, the exit surface from which the light from each light emitting portion emits and the entire incident surface from which the light from each light receiving portion is incident must be sufficiently in contact with the skin on the wrist surface, which is the subject site of the subject. There is. Therefore, it is preferable that each light emitting / receiving unit itself is not inclined toward the other sensor unit, but only each light emitting / receiving element included therein is inclined toward the other sensor unit.

  In order to more easily understand the arrangement of each light emitting / receiving element with respect to the artery of the measuring apparatus 100 according to the present embodiment, FIGS. 11A and 11B show the arrangement of each light emitting / receiving element at the test site. This is shown schematically. In both arteries, blood flows in the positive direction of the Y axis, and therefore the pulse wave also propagates in the same direction. Note that, in FIG. 11A, only the light emitting unit 121a and the light emitting unit 121b are shown as an example among the two light emitting units of each sensor unit. In FIG. 11B, only the light receiving portions 123a and 123b of each sensor unit are shown, and the two light emitting units of each sensor unit are not shown.

  Referring to FIG. 11A, the light emitting elements 124a and 124b included in the light emitting units 121a and 121b are inclined to the other sensor units 120b and 120a, and the respective optical axes are also directed to the other sensor units 120b and 120a. Tilt. By arranging in this way, the light emitted from the light emitting element 124a is unlikely to reach the curved portion of the upstream artery viewed from the sensor unit 120a because the optical axis is inclined toward the sensor unit 120b. Similarly, the light emitted from the light emitting element 124b is unlikely to reach the curved portion of the downstream artery viewed from the sensor unit 120b because the optical axis is inclined toward the sensor unit 120a. That is, the region where the light incident on the inside A2 of the living body is scattered can be limited to the straight part of the artery to some extent, and information on the pulse wave from the curved part of the artery that causes the phase difference reversal phenomenon is included. It becomes difficult. Thereby, the measuring apparatus 100 can measure the pulse wave with high accuracy.

  Referring to FIG. 11B, the light receiving elements 126a and 126b included in the light receiving portions 123a and 123b are inclined with respect to the other sensor portions 120b and 120a, and the optical axis of the light incident on each of them is also the other sensor portion 120b. , Inclined toward 120a. By arranging in this way, light scattered by the curved portion of the upstream artery viewed from the sensor unit 120a is almost eliminated, and other scattered light is incident on the light receiving element 126a. Similarly, light scattered by the curved portion of the downstream artery viewed from the sensor unit 120b is almost eliminated, and other scattered light is incident on the light receiving element 126b. That is, the scattered light detected by the light receiving elements 126a and 126b can be limited to a certain extent to the light scattered by the straight part of the artery, and the pulse wave from the curved part of the artery, which causes the phase difference reversal phenomenon. Information is almost eliminated. Thereby, the measuring apparatus 100 can measure the pulse wave with high accuracy. Further, by shifting the arrangement of the light receiving elements 126a and 126b toward the light shielding plates 150a and 150b, the light scattered from the curved portions of the arteries upstream and downstream of the sensor portions 120a and 120b can be more reliably excluded, and the light shielding effect can be obtained. Is further improved.

(Sixth embodiment)
FIG. 12A is a schematic diagram showing the arrangement of the sensor unit 120a of the measuring apparatus 100 according to the sixth embodiment of the present invention. FIG. 12B schematically shows a state in which the light emitting elements 124a and 125a and the light receiving element 126a of the measuring apparatus 100 according to the sixth embodiment of the present invention are arranged on the skin A1 on the wrist surface of the subject. It is AA sectional drawing of Drawing 12 (A). In FIG. 12A, only the sensor unit 120a is shown, and the sensor unit 120b is not shown. The blood in the artery flows from bottom to top (Y-axis positive direction), and thus the pulse wave also propagates in the same direction. In a state where the sensor unit 120a is arranged vertically (X-axis direction) along the artery, each light emitting / receiving unit emits the light emitting unit 121a, the light receiving unit 123a, and the light emitting unit so as to cross the artery in the positive direction of the X axis. They are arranged in the order of 122a. In FIG. 12B, which is a cross-sectional view of FIG. 12A, blood in the artery flows from the front to the back of the page (the Y-axis positive direction), and thus the pulse wave also propagates in the same direction. .

  In the sixth embodiment of the present invention, in addition to the inclination of each light emitting / receiving element described in the fifth embodiment toward the other sensor unit, each light emitting element is also inclined in the arterial direction. Also in the sixth embodiment, as in the other embodiments, the other sensor unit 120b is arranged at a predetermined interval in the positive Y-axis direction when viewed from the sensor unit 120a shown in FIG. The Therefore, the inclination direction of each light emitting / receiving element toward the other sensor portion is the Y-axis direction in FIG. On the other hand, the inclination direction of each light emitting element to the artery is the X-axis direction in FIG. That is, the optical axis of the light incident on the light receiving element 126a is inclined only in the Y-axis positive direction, and the optical axis of the light emitted from the light-emitting elements 124a and 125a is in addition to the Y-axis positive direction, as shown in FIG. As shown in FIG. Since the light emitting units 121a and 122a are arranged symmetrically in the X-axis direction with the artery as a boundary, the inclination directions of the optical axes of the light emitted from the light-emitting elements 124a and 125a are opposite to each other along the X-axis. . That is, as an example in FIG. 12B, the optical axis of the light emitted from the light emitting element 124a is inclined in the positive direction of the X axis, while the optical axis of the light emitted from the light emitting element 125a is in the negative direction of the X axis. Lean on.

  With this configuration, in this embodiment, the peak of the spatial intensity distribution of the emitted light from the light emitting elements 124a and 125a propagating through the living body inside A2 is inclined toward the arterial direction. That is, most of the light emitted from the light emitting elements 124a and 125a reaches the artery, and the scattered light intensity of the light scattered by the artery increases. Thereby, the intensity of the scattered light incident on the light receiving element 126a is also increased, and the SN ratio of the signal output from the light receiving element 126a is improved. In other words, in this embodiment, the measuring apparatus 100 can acquire a pulse wave waveform in which the noise is relatively less than the signal intensity, as compared with the case where the optical axis of each light emitting element is not inclined in the arterial direction. .

  FIG. 13 is a schematic diagram of a measurement system 1 including a measurement apparatus 100 that embodies at least one of the first to sixth embodiments described above. The measurement system 1 includes a server 200 and a display unit 300 in addition to the measurement apparatus 100. The server 200 collects biological information acquired by the measurement apparatus 100 and performs various information processing. The biometric information is aggregated by transmitting data to the server 200 by the measurement device 100 of each subject via a wired or wireless communication network. The display unit 300 displays the result processed by the server 200 based on the biological information acquired by the measurement apparatus 100. That is, the display unit 300 displays information based on the biological information acquired by the measuring apparatus 100.

  More specifically, the biological information acquired by the measurement apparatus 100 is transmitted to the server 200 by the communication unit of the measurement apparatus 100. When the server 200 receives the biological information transmitted from the measuring apparatus 100, the control unit of the server 200 performs various information processing based on the received biological information of the subject. For example, the server 200 can store the biological information acquired by the measurement apparatus 100 in the storage unit of the server 200 as time-series data together with the acquisition time of the biological information. The control unit of the server 200 compares, for example, these stored data with the past data of the same subject already stored in the storage unit of the server 200 or the data of other subjects, and compares them. Based on the result, the best advice for the subject is generated. The communication unit of the server 200 transmits the acquired time-series data of the subject and the generated advice to the display unit 300. The display unit 300 displays the received data and advice on the screen. In addition, a functional unit having the same functions as the storage unit and the control unit of the server 200 may be provided in the measurement device 100 or the display unit 300. In this case, the measurement system 1 does not necessarily include the server 200.

  It will be apparent to those skilled in the art that the present invention can be realized in other predetermined forms other than the above-described embodiments without departing from the spirit or essential characteristics thereof. Accordingly, the above description is illustrative and not restrictive. The scope of the invention is defined by the appended claims rather than by the foregoing description. Some of all changes that fall within the equivalent scope shall be included therein.

100 Measuring device 110 Mounting part 111 Back surface 112 Front surface 113a, 113b, 140a, 140b Opening 114, 115 Band part 120a, 120b Sensor part 121a, 121b, 122a, 122b Light emitting part 123a, 123b Light receiving part 124a, 124b, 125a, 125b Light emitting element 126a, 126b Light receiving element 134a, 134b Lens part 150a, 150b Light shielding plate 200 Server 300 Display part 1 Measurement system A1 Skin A2 Internal body R1, R2, R3, R4, B1, B2 Region V1 Ulna artery V2 Radial artery L1, L2 length

Claims (11)

A wearing part to be worn by the subject;
A first sensor unit and a second sensor unit supported by the mounting unit and having a light emitting unit and a light receiving unit, respectively,
The first sensor unit and the second sensor unit are configured so that when the biological information of the subject is acquired, the first sensor unit and the second sensor unit are configured so that the predetermined part of the subject is in a state where the mounting unit is attached to the subject. Arranged at predetermined intervals along the blood vessels of
At least one of the optical axis of light emitted from the light emitting unit and the optical axis of light incident on the light receiving unit in the first sensor unit is configured to be inclined toward the second sensor unit side.
measuring device. At least one of the optical axis of the light emitted from the light emitting unit and the optical axis of the light incident on the light receiving unit in the second sensor unit is configured to be inclined toward the first sensor unit.
The measuring apparatus according to claim 1. The light emitting unit includes a light emitting element,
The light receiving unit includes a light receiving element,
The measuring apparatus according to claim 1, wherein at least one of the light emitting element and the light receiving element is arranged to be inclined. The light emitting unit includes a light emitting element,
The light receiving unit includes a light receiving element,
The measuring apparatus according to claim 1, wherein at least one of a direction of light emitted from the light emitting element and a direction of light incident on the light receiving element is changed. The distance between the light emitting part in the first sensor part and the light emitting part in the second sensor part is the distance between the light receiving part in the first sensor part and the light receiving part in the second sensor part. Shorter than,
The measuring device according to any one of claims 1 to 4. The light emitting unit is disposed on both sides of the light receiving unit along a direction perpendicular to the predetermined blood vessel of the subject.
The measuring device according to any one of claims 1 to 5. The light receiving portion includes an opening having a predetermined diameter,
The measuring apparatus according to any one of claims 1 to 6. The wearing part is a band attached to the wrist of the subject.
The measuring apparatus according to any one of claims 1 to 7. The biological information is a pulse wave.
The measuring apparatus according to any one of claims 1 to 8. A control unit that calculates a pulse wave velocity based on the acquired pulse wave;
The measuring apparatus according to claim 9. A measuring apparatus according to any one of claims 1 to 10,
A display unit that displays information based on biological information acquired by the measurement device,
Measuring system.

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