JP2013000177A - Pulse wave measuring apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pulse wave measuring apparatus capable of highly accurately measuring pulse waves without coming into contact with a living body which is an object of measurement.SOLUTION: The pulse wave measuring apparatus irradiates an object with first electromagnetic waves of a first frequency, irradiates the object with second electromagnetic waves of a second frequency different from the first frequency, and receives reflected synthetic waves which are synthetic waves of first reflected waves, which are reflected electromagnetic waves from the object of the first electromagnetic waves, and second reflected waves, which are reflected electromagnetic waves from the object of the second electromagnetic waves. Then, the pulse wave measuring apparatus obtains a first difference output waveform by multiplying a reflected synthetic wave waveform and a first frequency waveform of the first frequency, obtains a second difference output waveform by multiplying the reflected synthetic wave waveform and a second frequency waveform of the second frequency, and obtains a measured value of displacement of a distance of the object on the basis of a phase difference between the first difference output waveform and the second difference output waveform.

Description

  The present invention relates to a pulse wave measuring device for measuring a pulse wave of a living body.

  Conventionally, pulse wave measuring devices such as a pressure wave sensor using a diaphragm and a photoelectric pulse wave detecting probe have been proposed as devices for detecting biological vibration waveforms, particularly pulse wave waveforms (Patent Documents 1 to 3). These devices detect AI (Augmentation Index) and PWV (Pulse Wave Velocity) of a subject by detecting and analyzing pulse pressure waveforms of peripheral arteries (carotid artery, radial artery, etc.). ing.

  For example, Patent Document 1 discloses a blood pressure measurement device that measures a blood pressure value of a living body, a pulse wave detection device that detects a pulse wave at a predetermined part of the living body, a blood pressure value measured by the blood pressure measurement device, and the pulse. Based on the magnitude of the pulse wave detected by the wave detection device, correspondence relation determining means for determining a correspondence relation for converting the magnitude of the pulse wave into a blood pressure value, and detected by the pulse wave detection device Traveling wave peak determining means for determining the magnitude of the peak of the traveling wave component included in the pulse wave, and the reflected wave for determining the occurrence point of the peak of the reflected wave component included in the pulse wave detected by the pulse wave detecting device Using the correspondence determined by the occurrence determination means and the correspondence determination means, the magnitude of the pulse wave at the peak occurrence time of the reflected wave component determined by the reflected wave generation time determination means, and the traveling wave Pi A pressure difference calculating means for calculating a pressure difference obtained by converting a difference value from the peak value of the traveling wave component determined by the determination means to a blood pressure value, and a display for displaying the pressure difference calculated by the pressure difference calculating means. An arteriosclerosis evaluation apparatus is disclosed that includes a blood vessel.

  Patent Document 2 calculates a plurality of feature quantities directly obtained from a pulse wave measuring means for measuring a subject's pulse wave and a predetermined feature point of the waveform of the pulse wave measured by the pulse wave measuring means. , A pulse wave feature amount calculating means for calculating an index reflecting the reflection phenomenon of the pulse wave by calculation between the calculated feature amounts, a blood pressure detecting means for detecting the blood pressure of the target person, and the pulse wave feature amount calculation The index calculated by the means and the blood pressure detected by the blood pressure detection means are presented in association with each other, and information on the medicine to be prescribed according to the level of the index and the blood pressure presented in association with each other There is disclosed a pulse wave measuring device including a presenting means for presenting.

  Patent Document 3 discloses a device for continuously monitoring a user's arterial blood pressure, and continuously detects the blood pressure by contacting the outer surface of the user's body at a position adjacent to the artery. Sensor means for generating a blood pressure signal, an attachment means for securely holding the sensor means in operative contact with the user's body at the position, and the signal generated by the sensor means. And a microprocessor means for determining the actual arterial blood pressure, the sensor means including a protrusion for detecting and transmitting a change in blood pressure, the protrusion causing at least partial occlusion of the artery at said position. An apparatus configured to be disclosed is disclosed.

  On the other hand, as a distance measuring device using electromagnetic waves, for example, Patent Document 4 discloses a distance measuring device that measures a distance to a measurement object, and includes signals having a plurality of different frequency components within a specific bandwidth. A signal source to output, a transmission unit for transmitting the signal as a wave, a traveling wave consisting of either a wave transmitted from the transmission unit or a signal output from the signal source, and transmitted from the transmission unit A mixed wave detector that detects a mixed wave with a reflected wave reflected by the measurement object, a frequency component analyzer that analyzes a frequency component of the mixed wave detected by the mixed wave detector, A distance calculation unit that obtains a distance spectrum by performing spectrum analysis on the data analyzed by the frequency component analysis unit and calculates the distance to the measurement object. Distance measuring apparatus is disclosed to.

As a distance measurement method using electromagnetic waves, for example, in Patent Document 5, three different microwaves are irradiated toward a target object, and a predetermined continuous wave is synthesized with scattered waves from the target object. A method of measuring a distance to the target object by converting into a beat signal and detecting a phase difference with respect to the beat signal, wherein the microwaves are respectively close to a first frequency f ₁ , a second frequency f ₂ , A phase difference φA is detected for a beat signal resulting from a frequency difference between the first frequency f ₁ and the second frequency f ₂ with a third frequency f _3, and the distance dA to the target object at the speed of light c is:
dA = cφA / {4π (f ₁ + f ₂ )}
When the distance dA exceeds one wavelength λA of the beat signal, the phase difference φB is detected for the beat signal due to the frequency difference between the first frequency f1 and the third frequency f3, and the light speed c The distance dB to the target object is
dB = cφB / {4π (f ₁ + f ₃ )}
The excess distance RA exceeding 1 wavelength λA and the excess distance RB exceeding 1 wavelength λB are calculated by:
RA = dA + nA · λA
RB = dB + nB · λB
Where the integers nA and nB are positive values and the residual e of the excess distances RA and RB is
e = RA-RB
Then, integers nA and nB that minimize the residual e are determined, and the excess distances RA and RB that have the same value by the determined integers nA and nB are set as the true value R of the distance d. A distance measurement method using a continuous wave type microwave sensor is disclosed.

Japanese Patent No. 3621379 Japanese Patent No. 4517619 JP 2002-119486 A JP 2007-93576 A JP 2008-45940 A

  As a method for evaluating the stiffness of an artery due to arteriosclerosis that progresses with age, there are a pulse wave velocity (PWV) and an AI (Augmentation Index). Pulse wave velocity is used to evaluate partial arterial stiffness and AI is used to evaluate arterial stiffness throughout the body. Conventionally, in order to determine the degree of arteriosclerosis caused by hyperlipidemia or the like, blood vessel mechanical data corresponding to blood vessel hardness has been measured. In particular, a pulse wave velocity (PWV) measurement method is used as a method for noninvasively measuring the hardness of a blood vessel. This pulse wave velocity can be obtained from the measurement of the pulse wave propagation time between two points (for example, between the carotid artery and the femoral artery, or between the brachial artery and the ankle artery) and the distance between the two points. It has become an evaluation index for arteriosclerosis.

  However, in the conventional apparatus, when AI is evaluated as an index of afterload for left ventricular contraction, evaluation with an ascending aortic pressure waveform is necessary. Therefore, clinical application is difficult.

  In order to cope with this problem, a system for estimating an aortic pressure waveform from a pulse waveform of a peripheral artery has been developed based on a generalized transfer function (GTF) of a pulse pressure wave (see Patent Document 3). However, the estimation of the aortic pressure waveform by GTF is difficult to be individualized, and there is a limit to the accurate detection of the pulse pressure waveform.

  Furthermore, in the measurement of pulse wave velocity, PWV in the aorta of the subject is estimated by detecting and analyzing the pulse pressure waveforms of the carotid artery, femoral artery, radial artery, upper arm, and ankle. Yes, it is difficult to directly detect the pulse wave velocity of the aorta other than invasive measurement.

  The present invention has been made in consideration of the above-described problems, and provides a pulse wave measurement device that can perform pulse wave measurement with high accuracy in a non-contact manner with respect to a living body that is a measurement target. For the purpose. That is, not only a biological vibration waveform (pulse waveform), particularly a peripheral artery pressure waveform, but also a pulse waveform of an aorta can be directly detected, and a pulse wave measuring device with high detection accuracy including non-periodic vibration is provided. The purpose is to provide.

  It is another object of the present invention to obtain a pulse wave measuring device that can detect a biological wave vibration in a non-contact manner, particularly a pulse wave waveform of the aorta, which is a vibration of an aortic blood vessel. In addition, the present invention provides a pulse wave measuring device that can directly detect an aortic pressure waveform without estimating an aortic pressure waveform from an average transfer characteristic (GTF) from a pulse waveform of a peripheral artery. With the goal.

  Further, the present invention can perform pulse wave measurement with high accuracy even when using a low-cost oscillation circuit with poor frequency stability, and therefore provides a pulse wave measurement device with high accuracy and low cost. Objective.

  The present inventors have found that a pulse wave measurement can be performed with high accuracy and non-contact on a living body that is an object of measurement by using a displacement measuring method of a predetermined distance using electromagnetic waves. It reached the pulse wave measuring device of the invention.

  The present invention irradiates an object with a first electromagnetic wave having a first frequency, irradiates the object with a second electromagnetic wave having a second frequency different from the first frequency, A reflected composite wave that is a composite wave of the first reflected wave that is the reflected electromagnetic wave and the second reflected wave that is the reflected electromagnetic wave from the object of the second electromagnetic wave is received, and the reflected composite wave waveform and the first frequency waveform are received. Multiplying the first differential output waveform by multiplying the reflected composite waveform and the second frequency waveform to obtain the second differential output waveform, the first differential output waveform and the second differential output waveform A pulse wave measuring device configured to obtain a measurement of a displacement of an object distance based on a phase difference.

  The pulse wave measuring device of the present invention includes being configured to irradiate an object with two electromagnetic waves, a first electromagnetic wave and a second electromagnetic wave. In this specification, the frequency of the first electromagnetic wave is referred to as the first frequency. Similarly, the frequency of the second electromagnetic wave is referred to as the second frequency. The first frequency and the second frequency are different frequencies. By using electromagnetic waves of two different frequencies, analysis based on the phase difference between the waveforms of the two electromagnetic waves becomes possible.

  The pulse wave measuring device of the present invention is a reflection that is a composite wave of a first reflected wave that is a reflected electromagnetic wave from an object of the first electromagnetic wave and a second reflected wave that is a reflected electromagnetic wave from the object of the second electromagnetic wave. Configured to receive the composite wave.

  By irradiating the object with two electromagnetic waves, the first electromagnetic wave and the second electromagnetic wave, the object reflects the first reflected wave that is the reflected electromagnetic wave from the object of the first electromagnetic wave and the object of the second electromagnetic wave. The second reflected wave, which is the reflected electromagnetic wave from, is reflected. In this specification, a combined wave of the first reflected wave and the second reflected wave is referred to as a reflected combined wave. The pulse wave measuring device of the present invention is configured to receive a reflected synthetic wave. By using a reflected synthetic wave to obtain a measurement value of the displacement of the distance of the object, it is possible to measure the displacement of the distance with high accuracy.

  The pulse wave measuring device of the present invention includes being configured to obtain a first differential output waveform by multiplying the reflected synthesized wave waveform and the first frequency waveform. In addition, the pulse wave measuring device of the present invention includes being configured to obtain a second differential output waveform by multiplying the reflected synthesized wave waveform and the second frequency waveform.

  The reflected combined wave received by the pulse wave measuring apparatus of the present invention becomes a reflected combined wave waveform in the circuit in the pulse wave measuring apparatus of the present invention. A first differential output waveform can be obtained by multiplying the reflected composite wave waveform by the first frequency waveform that is the first frequency. Similarly, the pulse wave measuring device of the present invention can obtain the second differential output waveform by multiplying the reflected composite wave waveform by the second frequency waveform that is the second frequency.

  The pulse wave measuring device of the present invention includes being configured to obtain a measurement value of the displacement of the distance of the object based on the phase difference between the first differential output waveform and the second differential output waveform.

  The pulse wave measuring device of the present invention can obtain a measurement value of the displacement of the distance of the object based on the phase difference between the first differential output waveform and the second differential output waveform. Based on this predetermined phase difference, the pulse wave measuring device of the present invention can obtain a measurement value of the displacement of the object distance with high accuracy. By using a living body as an object to be measured, the displacement of the living body surface due to a pulse wave can be measured in a non-contact manner as a displacement of the distance between the pulse wave measuring device and the object. A biological vibration waveform (a temporal change in biological vibration) can be obtained from a temporal change in the measurement value of the displacement of the distance of the object. Therefore, according to the present invention, a pulse wave measuring device that can obtain a biological vibration waveform with high accuracy without contact with a living body that is a measurement target, and that can perform pulse wave measurement based on the biological vibration waveform. Can be obtained.

  In addition, the displacement of the distance of the object measured in the pulse wave measuring device of the present invention includes the case where the displacement is zero, that is, the case where the object is not displaced (stopped).

  The pulse wave measuring device of the present invention is configured to obtain a measurement value of the displacement of the distance of the object based on the phase difference regarding the first electromagnetic wave having the first frequency and the second electromagnetic wave having the second frequency. In this configuration, a distance displacement measuring method based on a phase difference caused by arbitrary electromagnetic wave irradiation can be applied. For example, in the pulse wave measuring apparatus of the present invention, a method using a standing wave radar, a method using a quadrature detector, and the like can be applied.

  Further, according to the distance displacement measuring method of the pulse wave measuring device of the present invention, it is known that the resolution limit is not so different even if the frequency difference is greatly different. For example, it can be estimated to be 8.6266 μm at 100 MHz and 8.6264 μm at 1 MHz. This can be said that there is no problem with respect to the resolution even if an inexpensive oscillation circuit with poor frequency stability is used. Therefore, the pulse wave measuring device of the present invention can use a low-cost oscillation circuit with poor frequency stability.

  In the present invention, the pulse wave measuring device includes at least one electromagnetic wave oscillating unit, at least one reflected synthetic wave receiving unit, a first multiplying unit, a second multiplying unit, and a displacement measuring unit, The electromagnetic wave oscillating unit is configured to oscillate the first electromagnetic wave and the second electromagnetic wave and irradiate the object, and the reflected synthetic wave receiving unit receives the reflected synthetic wave to obtain a reflected synthetic wave waveform. The first multiplication unit is configured to obtain the first differential output waveform by multiplying the reflected composite wave waveform and the first frequency waveform, and the second multiplication unit is different from the first multiplication unit. And is configured to obtain a second differential output waveform by multiplying the reflected composite wave and the second frequency waveform, and the displacement measuring unit has a phase difference between the first differential output waveform and the second differential output waveform. To obtain the result of the measurement of the displacement of the distance of the object based on Configured, it is preferable that the pulse wave measuring device.

  In this specification, the electromagnetic wave oscillation part refers to a part configured to oscillate a first electromagnetic wave and a second electromagnetic wave and irradiate the object.

  In this specification, the reflected synthetic wave receiving unit refers to a part configured to receive a reflected synthetic wave and obtain a reflected synthetic wave waveform.

  In the present specification, the first multiplication unit refers to a part configured to obtain a first differential output waveform by multiplying the reflected composite wave waveform and the first frequency waveform.

  In this specification, the second multiplication unit is located at a different location from the first multiplication unit, and is configured to obtain a second differential output waveform by multiplying the reflected synthesized wave and the second frequency waveform. Refers to the part.

  In this specification, the displacement measuring unit refers to a part configured to obtain a measurement result of a distance displacement of an object based on a phase difference between a first differential output waveform and a second differential output waveform. Say.

  The pulse wave measuring device according to the present invention includes at least one electromagnetic wave oscillating unit, at least one reflected synthetic wave receiving unit, a first multiplying unit, a second multiplying unit, and a displacement measuring unit. It is possible to reliably measure the displacement of the distance with no contact and with high accuracy.

  In the pulse wave measuring apparatus of the present invention, the reflected combined wave waveform input to the first multiplier includes a waveform corresponding to the second reflected wave, and the reflected combined wave waveform input to the second multiplier is the first reflected wave. It is preferable to set the range of irradiation of the object of the first electromagnetic wave and the second electromagnetic wave by the electromagnetic wave oscillating unit so as to include a waveform corresponding to.

  As described above, in the distance displacement measuring method used in the pulse wave measuring apparatus of the present invention, the reflected composite wave waveform input to the first multiplier includes a waveform corresponding to the second reflected wave, and the second multiplier It is necessary that the reflected synthetic wave waveform input to the waveform includes a waveform corresponding to the first reflected wave. Since the input waveform to the first multiplier and the second multiplier includes a predetermined waveform, the predetermined phase difference can be reliably multiplied and the measurement result of the distance displacement of the object can be obtained with high accuracy. it can.

  The range of irradiation of the object of the first electromagnetic wave and the second electromagnetic wave by the electromagnetic wave oscillating unit is set, for example, by setting a component for emitting the first electromagnetic wave and the second electromagnetic wave, for example, an antenna in a predetermined direction and position. It can be carried out. For example, when two antennas are arranged in parallel at a predetermined position, the irradiation range is determined by the directional gain. In particular, by setting the irradiation range so that there is an overlap in the range of the half-value angle of each irradiation range in the object, the reflected composite wave waveform input to the first multiplication unit is a waveform corresponding to the second reflected wave. In addition, the reflected composite wave waveform input to the second multiplication unit may include a waveform corresponding to the first reflected wave.

  In the pulse wave measuring device of the present invention, the electromagnetic wave oscillating unit includes a first electromagnetic wave oscillating unit for irradiating the first electromagnetic wave and a second electromagnetic wave oscillating unit for irradiating the second electromagnetic wave. The measurement apparatus includes a first antenna that is a first electromagnetic wave oscillating unit and is a reflected synthetic wave receiving unit, and a second antenna that is a second electromagnetic wave oscillating unit and is a reflected synthetic wave receiving unit, It is preferable to set the positional relationship between the first antenna and the second antenna so that the antenna receives the reflected combined wave including the second reflected wave and the second antenna receives the reflected combined wave including the first reflected wave. .

  The first antenna has the functions of both the first electromagnetic wave oscillating unit and the reflected synthetic wave receiving unit, and the second antenna has the functions of both the second electromagnetic wave oscillating unit and the reflected synthetic wave receiving unit. And reception can be performed in one part, so that the cost of the pulse wave measuring device can be reduced. In addition, by setting the positional relationship between the first antenna and the second antenna to a predetermined positional relationship, a waveform necessary for obtaining a measurement value of the displacement of the distance of the object is provided to the first multiplication unit and the second multiplication unit. You can enter it reliably.

  As the antenna, a pyramid horn antenna, a conical horn antenna, a dielectric rod antenna, a patch antenna, an antenna having an absolute gain close to these, and an antenna obtained by arraying and increasing the gain can be appropriately selected and used. . Moreover, it is also possible to use a high gain antenna which is an array of low gain antennas such as a leaky wave antenna and a slot antenna. The first antenna and the second antenna are not necessarily the same type of antenna. However, in order to facilitate the setting of the irradiation range so that there is an overlap in the range of the half-value angle of the electromagnetic wave irradiation range, the first antenna and the second antenna are preferably the same type of antenna, More preferably, the antennas are of the same type and shape.

  Further, the pulse wave measuring device of the present invention includes a first electromagnetic wave irradiation region corresponding to a half-value angle on the object surface of the first electromagnetic wave, and a second electromagnetic wave irradiation corresponding to a half-value angle on the object surface of the second electromagnetic wave. It is preferable to set a range of irradiation of the object of the first electromagnetic wave and the second electromagnetic wave by the electromagnetic wave oscillating unit so that there is a portion where the region overlaps.

  The “half-value angle” refers to an angle formed by a point that is half the power with respect to the power at the highest point of the electromagnetic wave. As described above, in the distance displacement measuring method used in the pulse wave measuring device of the present invention, both the first electromagnetic wave and the second electromagnetic wave are irradiated at a predetermined intensity on the same part of the object surface. is required. In the pulse wave measuring device of the present invention, the range of irradiation of the object of the first electromagnetic wave and the second electromagnetic wave by the electromagnetic wave oscillating unit is a first electromagnetic wave irradiation region corresponding to the half-value angle on the object surface of the first electromagnetic wave, It is necessary that there is a portion where the second electromagnetic wave irradiation region corresponding to the half-value angle on the object surface of the second electromagnetic wave overlaps.

  The range of irradiation of the object of the first electromagnetic wave and the second electromagnetic wave can be set by adjusting the shape, the irradiation direction, and the irradiation intensity of the electromagnetic wave that is the electromagnetic wave oscillation unit.

  The object surface for pulse wave measurement is a surface of a living body that is an object on which a blood vessel capable of pulse wave measurement is located.

  The area of the portion where the first electromagnetic wave irradiation area and the second electromagnetic wave irradiation area overlap is preferably 50% or more with respect to the area of the entire irradiation area. Further, it is necessary that the range of the overlapping portion includes the range of the blood vessel to be measured for the pulse wave. In particular, it is preferable to set the range of irradiation of the object of the first electromagnetic wave and the second electromagnetic wave so as to occupy 80% or more of the area of the overlapping portion of the area of the blood vessel.

As shown in FIG. 4, and the radius of the portion where the first electromagnetic wave and the second wave overlap and r _A, the radius r _A may be a radius r _A, as θ becomes half-value angle. The portion where the first electromagnetic wave and the second electromagnetic wave overlap is the part to be measured. Since high-accuracy measurement can be reliably performed, the radius r _A for reliably performing the measurement of biological vibration is set to be not more than three times the diameter φ _t of a blood vessel that differs for each measurement site as shown below. It is preferable. Diameter phi _t of the vessel for each measurement site, aortic root at the phi _t = 20 to 30 mm, in the abdominal aorta φ _t = 14~20mm, the iliac arteries phi _t = 6 to 10 mm, in brachial arterial phi _t = 5 to 8 mm, φ _t = 2 to 4 mm (specifically 3 mm) for the arteries of the lower arm or ankle, and φ _t = 0.2 to 0.5 mm for arterioles.

  In the pulse wave measuring apparatus of the present invention, it is preferable that the first electromagnetic wave and the second electromagnetic wave are directly oscillated by the electromagnetic wave oscillating unit, obtained by harmonics of the oscillated electromagnetic wave, or obtained by multiplication.

  “Direct oscillation” means that the fundamental frequency oscillated by the electromagnetic wave oscillation unit is used as it is. The term “harmonic of electromagnetic waves” refers to a waveform having a frequency that is an integral multiple of the waveform of the fundamental frequency oscillated by the electromagnetic wave oscillating unit. “Multiplication” refers to generating an integer multiple of a frequency based on the waveform of the fundamental frequency oscillated by the electromagnetic wave oscillation unit.

  The first electromagnetic wave and the second electromagnetic wave are not necessarily obtained by the same oscillation method. For example, different oscillation methods can be used such that the first electromagnetic wave is directly oscillated by the electromagnetic wave oscillating unit and the second electromagnetic wave is obtained by harmonics of the oscillated electromagnetic wave. The oscillation can be performed by using a transmitter such as a variable frequency transmitter and a continuous wave oscillator. Specifically, for example, a dielectric resonant oscillator, an LC resonant oscillator with a pattern, an LC resonant oscillator with a lumped constant, or the like can be used as the transmitter.

  In the pulse wave measuring device of the present invention, the reflected composite wave waveform is input to the first multiplier and the second multiplier, which are two mixers arranged at a predetermined distance, and the phase difference is two. The phase difference of the mixer output waveform is preferable.

  By using a mixer as the first multiplier and the second multiplier, the reflected composite wave can be easily multiplied by the first frequency waveform or the second frequency waveform. A differential output waveform can be obtained. Further, since the first differential output waveform and the second differential output waveform are the output waveforms of the two mixers (the first multiplier and the second multiplier), the target is determined based on the phase difference between the output waveforms of the two mixers. The result of measurement of the displacement of the object distance can be obtained.

A non-linear mixer can be used as the mixer. Moreover, it can be set as the apparatus which drives a nonlinear mixer using the electric power of an electromagnetic wave oscillation part. Therefore, since a secondary spectrum appears at the outputs of the first multiplier and the second multiplier, a desired frequency component (for example, f ₁₎ can be obtained by appropriately combining filters such as a high-pass filter, a low-pass filter, and a band-pass filter. preferably comprises a frequency selector for selecting -f _2). The first multiplication unit and the second multiplication unit, for example, input the first frequency waveform or the second frequency waveform by injecting and driving the first frequency waveform or the second frequency waveform using a Schottky diode. The reflected combined wave can be multiplied.

In the pulse wave measuring device of the present invention, the first frequency and the second frequency are preferably 7 GHz or more. Since the fluctuation amount at the time of contraction / dilation of the blood vessel is about 100 μm, it is considered necessary to have a distance accuracy Δλ (μm / degree) for a phase difference of about 1/3 of about 33 μm. Therefore, from FIG. 27, it is desirable that the frequency is 7 GHz or more. The relationship between Δλ and frequency [GHz] can be expressed by the following equation.
Δλ = 207.75 / (frequency [GHz])

In the distance displacement measuring method used in the pulse wave measuring device of the present invention, the measurement resolution improves if the sum (f ₁ + f ₂ ) of the first frequency f ₁ and the second frequency f ₂ increases. Therefore, the resolution of pulse wave measurement can be improved by using an electromagnetic wave having a frequency of 7 GHz or more, preferably 10 GHz or more, more preferably 24 GHz or more.

  In the pulse wave measuring apparatus of the present invention, it is preferable that the first frequency and the second frequency are frequencies between 10 GHz and 100 GHz.

As described above, in the distance displacement measuring method used in the pulse wave measuring device of the present invention, if the sum (f ₁ + f ₂ ) of the first frequency f ₁ and the second frequency f ₂ increases, the measurement resolution Therefore, it is preferable to use high frequency electromagnetic waves. However, when the frequency is too high, the light is reflected on the skin surface, so that the invasiveness is weak and the laser measurement approaches. Therefore, the first frequency and the second frequency are preferably 10 GHz to 100 GHz, preferably 15 GHz to 60 GHz, and more preferably 20 GHz to 30 GHz.

  Further, the pulse wave measuring apparatus of the present invention irradiates the object with the first electromagnetic wave and the second electromagnetic wave, the reflected synthetic wave receiving unit is two antennas, the two antennas are the first multiplier unit and It is preferable that each of the first multipliers is connected.

  The pulse wave measuring device has two antennas and is connected to the first multiplication unit and the first multiplication unit, respectively, so that the multiplication of a predetermined waveform in the first multiplication unit and the first multiplication unit can be accurately and reliably performed. Can be done.

  In the pulse wave measuring device of the present invention, the displacement measuring unit removes the displacement based on at least one of respiration, body motion, and movement of the pulse wave measuring device included in the distance displacement. It is preferable to provide a removal unit.

  In general, the waveform measured by the displacement measuring unit shows a waveform in which respiration, body movement, and the like are superimposed in addition to the pulse wave. If the pulse wave measurement is affected by the displacement of the distance due to respiration, body movement, movement of the pulse wave measurement device, etc., the pulse wave measurement may not be performed accurately. Therefore, the accuracy of pulse wave measurement can be improved by removing the displacement based on at least one of respiration, body movement, and movement of the pulse 1 wave measurement device included in the distance displacement.

  The removal of the predetermined displacement in the extra-pulse wave displacement removing unit is, for example, separately measuring the distance displacement due to breathing, body movement, movement of the pulse wave measuring device, etc., and comparing the measurement result with the pulse wave measurement result. Can be done. In general, breathing shows a waveform with a large amplitude with a period of 3 to 4 seconds, and a pulse wave shows a small waveform with a period of about 1 second, so by analyzing the waveform measured by the displacement measuring unit, A predetermined displacement can be removed in the displacement removing unit.

  In the pulse wave measuring device of the present invention, it is preferable that the displacement measuring unit continuously obtains the measurement result of the displacement of the distance of the object.

  In order to measure the pulse wave, it is necessary to measure the time change of the displacement of the distance. Therefore, it is preferable to obtain continuously the measurement result of the displacement of the distance of the object. The displacement measuring unit can obtain pulse wave measurement reliably by continuously obtaining the measurement results of the displacement of the distance of the object.

  In addition, the pulse wave measurement device of the present invention preferably includes an index calculation unit that obtains a calculation result of an index related to the pulse wave based on the displacement of the distance of the object measured by the displacement measurement unit.

  The index relating to the pulse wave refers to the stiffness of the artery, the estimated value of the pulse wave velocity (PWV), AI (Augmentation Index), CAVI (Cardio Ankle Vascular Index), and the like. The index calculation unit is a part configured to obtain the calculation result of the index related to the pulse wave using the measurement result of the displacement of the distance of the object obtained by the displacement measurement unit. By providing the index calculation unit, it is possible to reliably calculate the index related to the pulse wave.

  In the pulse wave measuring device of the present invention, the pulse wave index includes a maximum value or a minimum value of displacement of distance with respect to time, a time between a plurality of maximum values or minimum values, or a plurality of maximum values or minimum values. It is preferable that the index is calculated based on the difference between the values.

A pulse wave velocity will be described as a specific example as an index related to a pulse wave. FIG. 3 shows an example of the measurement result of the displacement of the distance of the object obtained by the pulse wave measuring device of the present invention. In FIG. 3, the horizontal axis (x-axis) is time, and the vertical axis (y-axis) is the output voltage proportional to the displacement of the distance of the object. The object in the case of FIG. 3 is a human, and there are two distance displacement measurement sites: the aortic root (referred to as “A point”) and the descending aorta (referred to as “B point”). As is clear from FIG. 3, the displacement of the distance with respect to time at both measurement sites shows several local maximum values. As an index related to the pulse wave in FIG. 3, for example, when measuring the pulse wave velocity, the pulse wave related to the maximum value A1 of the aortic root (point A) propagates through the blood vessel and becomes the maximum value B1 of the descending aorta (point B). It is thought that it was measured. When the time difference between the maximum value A1 and the maximum value B1 is Δt and the distance between the separately measured points A and B is L, the pulse wave velocity (PWV) can be obtained by the following equation (101). it can.
PWV = L / Δt (101)

  In the example of FIG. 3, the time difference (Δt) between the maximum value A1 and the maximum value B1 is 0.05 seconds, and the distance (L) between the points A and B measured separately is 20 cm. It can be said that the pulse wave velocity (PWV) is 4 m / sec.

Next, as an index related to the pulse wave by using the maximum value of the displacement of the distance with respect to time, an AI (Augmentation Index) is taken as an example, and how to find it will be described. In FIG. 3, it can be seen that the maximum value A2 is observed 0.15 seconds after the maximum value A1 at the aortic root (point A). It can be said that the maximum value A2 is caused by the reflected wave that the pulse wave related to the maximum value A1 propagates through the blood vessel to reach the descending aortic bifurcation and the pulse wave is reflected there. Assuming that the maximum value A1 is P1, the maximum value A2 is P2, and the larger value of P1 and P2 is PP, ΔP = (P2−P1), and AI is expressed by the following equation (101): Can be sought.
AI = ΔP / PP (101)
In addition, the value which subtracted the background can be used for the value P1 of the maximum value A1 and the value P2 of the maximum value A2.

  In the above-described example of the measurement of the pulse wave velocity, the case of obtaining from the measurement at the two measurement sites of the aortic origin and the descending aorta measurement site has been described. However, the pulse wave velocity can be measured by measuring the pulse wave velocity at one place by using the reflected wave of the pulse wave from the descending aortic bifurcation as described in the method of obtaining AI.

  As described above, the pulse wave index is calculated based on the maximum value of the displacement of distance with respect to time, the time between a plurality of maximum values, or the difference between the values between the maximum values, taking the pulse wave velocity and AI as an example. The method was described. Further, similarly to the case based on the above-described maximum value, the pulse wave is based on the minimum value of the displacement of the distance with respect to time, the time between the plurality of minimum values, or the difference between the values between the plurality of minimum values. An index can also be calculated. If the pulse wave measuring device of the present invention is used, the maximum value or the minimum value of the displacement of the distance with respect to time can be measured. Therefore, the maximum value of the displacement of the distance with respect to time or the index other than the pulse wave velocity and AI can be measured. By using the minimum value, it is possible to easily calculate.

  In the pulse wave measuring device of the present invention, it is preferable that the index is an index related to the hardness of the artery.

  Generally, as arteriosclerosis progresses, the blood vessels lose elasticity and the pulse wave velocity increases. Therefore, the stiffness of the artery can be estimated using the pulse wave velocity as an index, and information regarding the progression of arteriosclerosis can be obtained. Specifically, for example, information on the arteriosclerosis of the central blood vessel can be obtained by analyzing the pulse wave waveform of the ejection wave from the heart and the reflection wave from the peripheral blood vessel.

  In the pulse wave measuring device of the present invention, the index is preferably an estimated value of pulse wave velocity or AI.

  As described above, the pulse wave velocity and AI can be calculated based on the maximum value of the displacement of the distance with respect to time by the pulse wave measuring device of the present invention. By using these indicators, arteriosclerosis, hypertension / hyperlipidemia, obstructive hypertrophic cardiomyopathy, dilated cardiomyopathy, aortic regurgitation, hyperthyroidism, obstructive arteriosclerosis / diabetes, etc. The presence / absence or degree of a medical condition related to at least one of the blood vessels can be evaluated.

  Further, the pulse wave measuring device of the present invention sets a determination result corresponding to a preset pattern, and a displacement pattern of the distance of the object measured by the displacement measuring unit, and a preset pattern. It is preferable to provide a determination unit that compares and obtains a determination result based on the comparison result.

  The preset pattern is a pattern of time change of the displacement of the distance of the object to be measured, which typically appears in the case of a medical condition such as arteriosclerosis, and is a predetermined pattern determined by measurement in advance. It means a pattern. The judgment unit compares the displacement pattern of the distance of the object measured by the displacement measurement unit with a preset pattern, and obtains the result of judgment of the presence or absence of the medical condition, etc., and easily in a short time The determination result can be obtained.

  In addition, the pulse wave measuring device of the present invention has a determination result of normal, arteriosclerosis, hypertension / hyperlipidemia, obstructive hypertrophic cardiomyopathy, dilated cardiomyopathy, aortic regurgitation, hyperthyroidism It is preferable that it is the result of the determination regarding at least one of infectious disease, obstructive arteriosclerosis, and diabetes.

  By measuring information on pulse waves with the pulse wave measuring device of the present invention, normal, arteriosclerosis, hypertension / hyperlipidemia, obstructive hypertrophic cardiomyopathy, dilated cardiomyopathy, aortic regurgitation, thyroid gland The determination result regarding at least one of hyperfunction, obstructive arteriosclerosis, and diabetes can be easily obtained with high accuracy.

  In addition, the pulse wave measuring device of the present invention includes storage means for associating and storing the result together with pulse wave information in which the displacement of the distance of the object measured by the displacement measuring unit is recorded at a predetermined sampling rate for a predetermined time. Is preferred.

  The storage means stores the displacement of the distance of the object measured by the displacement measuring unit in association with the pulse wave information recorded at a predetermined sampling rate for a predetermined time, and stores the result in association with the pulse wave information. Since a certain pulse wave pattern (a time change in the measured displacement of the object) can be easily scrutinized, a doctor or the like can easily and accurately analyze a more detailed medical condition.

  The predetermined sampling rate is preferably 10 sps or more, more preferably 10 to 400 sps, and further preferably 100 to 300 sps.

  The “storage means” is preferably a device that can electronically store pulse wave information, such as a known hard disk drive, CD drive, DVD drive, and various memories, because the association can be facilitated.

  Further, the pulse wave measuring apparatus of the present invention includes a notifying unit for notifying a result, and a notification mode for a measurement abnormality in which a result is not obtained is different from a notification mode for a measurement result when a result is obtained. It is preferable to set it as an aspect.

  It is preferable that the notifying means for notifying the result notifies both the notification mode in the case of a measurement abnormality in which the result cannot be obtained and the notification mode of the measurement result in the case where the result is obtained. By providing an informing means for informing in the case of a measurement abnormality for which a result cannot be obtained, remeasurement by a doctor or the like can be reliably performed. In addition, by providing a notifying means for notifying when a result is obtained, it is possible to ensure that a doctor or the like copes without overlooking particularly when the medical condition is not normal.

  Specifically, known means such as an alarm on the operation display of the pulse wave measuring device, an acoustic warning device such as a warning light and a buzzer arranged separately can be used as the notification means.

  Further, the pulse wave measuring device of the present invention includes a plurality of the above-described pulse wave measuring devices, and the object of each pulse wave measuring device is set at a position corresponding to a blood vessel of a different part of the same person, It is preferable that the pulse wave measuring device calculates an index relating to a pulse wave based on a deviation of the measurement result of the displacement of the distance of the object output from the displacement measuring unit.

  As described above, for example, when measuring the pulse wave velocity, in addition to the method of obtaining from the measurement at two measurement sites of the aortic origin and the descending aorta measurement site, the descending described in the measurement of AI By using the reflected wave of the pulse wave from the aortic bifurcation or the like, the pulse wave velocity can be measured by measuring the pulse wave velocity at one location. However, since the reflection of the pulse wave does not always occur at the expected location, the pulse wave measurement device includes a plurality of the pulse wave measurement devices, and the object of each pulse wave measurement device corresponds to a blood vessel of a different part of the same person. It is preferable to calculate the index related to the pulse wave based on the deviation of the measurement result of the displacement of the distance of the object output from the displacement measuring unit of each pulse wave measuring device.

  As an index related to the pulse wave, for example, the time difference between the characteristic points as a result of the measurement of the displacement of the distance from the object output from the displacement measuring unit of each pulse wave measuring device, and the distance between different parts of the same person It is good to use it as the index regarding the pulse wave velocity obtained based on. The characteristic points may be the rising point and peak (maximum value or minimum value) of the pulse waveform of the measurement result, and the pulse waveform to be compared is the pulse waveform of two similar patterns that are closest in time. It is good to do.

  The pulse wave measuring device of the present invention further includes an object fixing means for fixing the object, and the object fixing means is preferably a bed or a chair.

  Since the object of pulse wave measurement is a living body, movement may occur. For accurate pulse wave measurement, it is preferable to prevent extra movement other than the pulse wave as much as possible. The pulse wave measuring device of the present invention further includes an object fixing means for fixing the object, thereby preventing extra movement other than the pulse wave as much as possible and improving the measurement accuracy.

  A well-known thing can be used for a target fixing means. In particular, the object fixing means is preferably a bed or a chair. When the pulse wave measuring device of the present invention is arranged in a building such as a hospital, for example, a bed or a chair can be used as the object fixing means. The bed or chair can further include a band for fixing the object.

  In addition, since the pulse wave measuring device of the present invention can measure the displacement of the distance, it can be applied to body motion measurement other than the pulse wave. For example, a device for measuring heartbeat and respiration can be obtained by applying the pulse wave measuring device of the present invention.

  ADVANTAGE OF THE INVENTION According to this invention, the pulse-wave measuring apparatus which can perform a pulse-wave measurement with high precision in non-contact with respect to the biological body which is a measuring object can be provided. Further, according to the present invention, not only the biological vibration waveform (pulse waveform), particularly the peripheral artery pressure waveform, but also the pulse waveform of the aorta or the like can be directly detected, and the detection accuracy including non-periodic vibration can be achieved. A high pulse wave measuring device can be provided.

  In addition, according to the pulse wave measuring device of the present invention, it is possible to detect a living body vibration, in particular, a pulse wave waveform of the aorta that is a vibration of the aortic blood vessel without contact. For this reason, it is not necessary to estimate the aortic pressure waveform from the pulse waveform of the peripheral artery by means of an average transfer characteristic (Generalized Transfer Function; GTF), and the aortic pressure waveform can be directly detected.

  In addition, the pulse wave measuring device of the present invention can perform pulse wave measurement with high accuracy even when a low-cost oscillation circuit with poor frequency stability is used. Therefore, the pulse wave measuring device with high accuracy and low cost can be obtained. Can be provided.

It is a schematic diagram which shows an example of the pulse-wave measuring apparatus of this invention. It is a figure which shows the relationship between phase difference (phi) of the synthetic wave waveform of 0.8 MHz, and distance d. It is a pulse wave waveform of Example 3, Comprising: It is an example of the pulse wave measurement result between 2 points | pieces (L = 20cm) of an adult woman in her 50s. In the pulse wave measuring device of the present invention, it is a schematic diagram for explaining a part (measurement part) where the first electromagnetic wave and the second electromagnetic wave overlap. It is a schematic diagram of the system configuration | structure of the pulse-wave measuring apparatus of Example 1 of this invention. It is an example of the pulse wave measurement procedure using the pulse wave measuring device of the present invention. It is a schematic diagram which shows the propagation of the pulse wave in the blood vessel. It is a figure which shows an example of the waveform with which the respiration and pulse wave which were measured using the pulse wave measuring apparatus of Example 1 of this invention were superimposed. It is a figure which shows an example of the detailed pulse wave waveform acquired by the pulse wave measurement procedure using the pulse wave measuring apparatus of Example 1 of this invention. It is a schematic diagram of the system configuration | structure of the pulse-wave measuring apparatus of Example 2 of this invention. In Example 2, it is a wave form diagram which shows an example of the data in which the respiration and the pulse wave of the adult woman (50s) who lay on their back on the bed were mixed. In FIG. 11, it is the wave form diagram which expanded the part (6 sec-10 sec) of the pulse wave waveform which asked the subject to stop breathing intentionally only for 4 to 5 seconds and measured the waveform in the apnea state. It is the wave form diagram which expanded a part (7.2 sec-8.4 sec) of Drawing 12 further. In Example 2, it is a figure which shows an example of the pulse wave waveform of an adult male (60s). It is a figure which shows the pulse wave waveform which expanded a part (9.1 sec-9.9 sec) of FIG. In FIG. 3 which shows the pulse wave waveform of Example 3, it is a figure which shows the pulse wave waveform which expanded the aortic origin part and the descending aortic wave waveform part (7 sec-9 sec). In Example 3, it is a schematic diagram which shows the positional relationship as which two moving body detection sensors (Sensor1 and Sensor2) were arrange | positioned only the distance L1, and it assumed L2 from Sensor2 to the descending aortic bifurcation. In Example 3, it is a figure which shows the pulse wave waveform of the aortic origin part of a 50s adult woman. It is a figure which shows the pulse wave waveform which expanded a part (7.2 sec-8.4 sec) of FIG. In Example 3, it is a figure which shows the pulse wave waveform of the aortic origin part of a 60s adult male. It is a figure which shows the pulse wave waveform which expanded a part (9.1 sec-9.9 sec) of FIG. It is a schematic diagram which shows the outline | summary of the pulse-wave measuring system used for Example 4 of this invention. In Example 4, it is a figure which shows the pulse wave measurement result between 2 points | pieces (aortic origin part and femoral artery) (L = 57 cm) of an adult woman in her 50s. FIG. 23 is an enlarged view of the pulse waveform (5 sec to 10 sec) of the aortic root and femoral artery measured in the apnea state. FIG. 23 is an enlarged view of the pulse waveform (15 sec to 20 sec) of the aortic root and femoral artery measured in the apnea state. In Example 4, the pulse wave waveform between two points (L = 20 cm), an aortic origin (point A) and a descending aorta (point B (point B)) in an adult female in their 50s is shown. It is a figure which shows the change with respect to the frequency band of distance precision (DELTA) lambda (micrometer / degree).

  The present invention is a pulse wave measuring apparatus configured to measure a pulse wave based on a measured value of a distance displacement of an object such as a living body obtained by a displacement measuring method of a predetermined distance. The distance displacement measuring method used in the pulse wave measuring apparatus of the present invention can measure the distance displacement in a non-contact and highly accurate manner. Therefore, according to the present invention, it is possible to provide a pulse wave measurement device that can perform pulse wave measurement with high accuracy in a non-contact manner with respect to a living body that is an object to be measured.

  The method for measuring the displacement of the distance of the object 50 in the pulse wave measuring device of the present invention will be specifically described with reference to FIG. In this specification, one antenna and a circuit attached to the antenna may be referred to as a “moving body detection sensor”. For example, the first antenna 12 in FIG. 1 and a circuit attached to the first antenna 12 (for example, a portion represented by reference numeral A1 in FIG. 1) are “moving body detection sensors”. Similarly, the second antenna 22 “moving body detection sensor” and a circuit attached to the second antenna 22 (for example, a portion represented by reference numeral A2 in FIG. 1) are “moving body detection sensors”. In FIG. 1, the devices in the range of the antennas 12 and 22 and the dotted line C may be referred to as “microwave minute displacement sensor”.

The pulse wave measuring device of the present invention shown in FIG. 1 includes a first antenna (first electromagnetic wave oscillating unit) 12 and a second antenna (second electromagnetic wave oscillating unit) 22 as electromagnetic wave oscillating units. The electromagnetic wave oscillation unit can oscillate the first electromagnetic wave and the second electromagnetic wave and irradiate the object. Here, two electromagnetic waves output from the electromagnetic wave oscillation unit of the pulse wave measuring device, that is, a first electromagnetic wave indicated as V ₁ (t) and a second electromagnetic wave indicated as V ₂ (t),
V ₁ (t) = A cos 2πf ₁ t (1)
V ₂ (t) = A cos 2πf ₂ t (2)
In this case, the irradiation wave V _t (t) toward the object 50 (the combined wave of V ₁ (t) and V ₂ (t)) is
V _t (t) = A cos 2πf ₁ t + A cos 2πf ₂ t (3)
It can be expressed as. In Expression (3), A is the amplitude, f ₁ and f ₂ are the frequencies of the first electromagnetic wave and the second electromagnetic wave, respectively, and t is the time.
The reflected composite wave V _r (t) reflected (scattered) from the object 50 is
V _r (t) = αA cos 2πf ₁ (t−τ) + αA cos 2πf ₂ (t−τ) (4)
It can be expressed as. In Expression (4), α is an attenuation coefficient. The reflected synthesized wave V _r (t) can be received by the reflected synthesized wave receiving unit. In the example of FIG. 1, the first antenna 12 and the second antenna 22 also serve as a reflected synthetic wave receiving unit.

The round-trip time τ from the pulse wave measuring device to the object 50 is
τ = 2d / c (5)
It can be expressed as. In equation (5), d is the distance to the object 50, and c is the speed of light.

The reflected synthesized wave received by the reflected synthesized wave receiving unit is taken into the first multiplication unit (mixer 14) as a reflected synthesized wave waveform, and the first multiplied unit multiplies the reflected synthesized wave waveform by the first frequency waveform. A first differential output waveform number V _c1 is obtained. The reflected composite wave waveform is also taken into the second multiplication unit (mixer 24), and the second differential output waveform _Vc2 is obtained by multiplying the reflected composite wave waveform and the second frequency waveform in the second multiplication unit. That is, the first differential output waveform V _c1 is a combination of the reflected composite wave waveform V _r (t) and the first electromagnetic wave V ₁ (t), and the second differential output waveform V _c2 is a reflected composite wave waveform V _r. (T) and the second electromagnetic wave V ₂ (t) are combined,
V _c1 = αA ² [cos 2πf ₁ t · cos 2πf ₁ (t−τ)]
_{^{+ ΑA 2 [cos2πf1t · cos2πf 2}} (t-τ)] ··· (6)
V _c2 = αA ² [cos 2πf ₂ t · cos 2πf ₁ (t−τ)]
+ ΑA ² [cos2πf ₂ t · cos2πf ₂ (t−τ)] (7)
It can be expressed as. These equations (6) and (7) are trigonometric product formulas (8)
cos α cos β = cos (α−β) / 2 + cos (α + β) / 2 (8)
To obtain the following equations (9) and (10).

^{_{V c1 = [αA 2/2}} ] [cos {(2πf 1 -2πf 1) t + 2πf 1 τ}
+ Cos {(2πf ₁ + 2πf ₁ ) t−2πf ₁ τ}
+ Cos {(2πf ₁ -2πf ₂ ) t + 2πf ₂ τ}
+ Cos {(2πf ₁ + 2πf ₂ ) t-2πf ₂ τ}]
... (9)
^{_{V c2 = [αA 2/2}} ] [cos {(2πf 2 -2πf 1) t + 2πf 1 τ}
+ Cos {(2πf ₂ + 2πf ₁ ) t−2πf ₁ τ}
+ Cos {(2πf ₂ −2πf ₂ ) t + 2πf ₂ τ}
+ Cos {(2πf ₂ + 2πf ₂ ) t-2πf ₂ τ}]
... (10)
2πf ₁ , 2πf ₁ + 2πf ₂ , 2πf ₂ and the direct current component are removed from the waveforms of the equations (9) and (10) by a filter, and the following equations (11) and (12) are obtained, respectively.

^{_{V c1 = [αA 2/2}} ] [cos {(2πf 1 -2πf 2) t + 2πf 2 τ}]
(11)
^{_{V c2 = [αA 2/2}} ] [cos {(2πf 2 -2πf 1) t + 2πf 1 τ}]
(12)
Then, when the phase difference φA is obtained for the first differential output waveform V _c1 represented by Expression (11) and the second differential output waveform V _c2 represented by Expression (12),
φA = (2πf ₁ + 2πf ₂ ) τ (13)
It becomes. Since the round-trip time τ is related to the equation (5), the phase difference φA is
φA = 4π (f ₁ + f ₂ ) d / 2 (14)
Can be expressed as Therefore, the distance dA to the object 50 is obtained from the two-frequency phase difference φA of the synthesized waveform (f ₁ · f ₂ , f ₂ · f ₁ ),
dA = cφA / {4π (f ₁ + f ₂ )} (15)
It becomes. Here, the maximum measurable distance λA of the distance dA corresponds to the case where the phase difference φA is 2π,
λA = 2πc / {4π (f ₁ + f ₂ )} = c / 2 (f ₁ + f ₂ ) (16)
It can be expressed as.

As an example, when f ₁ = 24.1498 GHz and f ₂ = 24.1490 GHz, and c = 3 × 10 ¹¹ mm / sec in equation (16), the maximum measurable distance λ is
λ = 3 × 10 ¹¹ /(2×48.2988×10 ⁹ ) = 3.1026 mm
It becomes.
Therefore, the distance d to the reflector is obtained from the phase difference φ of the composite wave waveform at f ₁ −f ₂ = 0.8 MHz.

FIG. 2 shows the relationship between the phase difference φ of the 0.8 MHz synthesized wave waveform and the distance d. In this figure, when the phase difference φ of the synthesized wave waveform of 0.8 MHz is detected with 1 ° accuracy, the distance d = 0. 986 mm corresponding to the phase difference φ = 1 ° of f ₁ + f ₂ , that is, 8.6 μm. This shows that it can be determined with accuracy. That is, the phase angle φ of f ₁ + f ₂ = 48.2988 GHz can be obtained from the phase angle φ of the composite wave of 0.8 MHz, and as a result, an amplification effect of phase accuracy occurs.

  In other words, it is possible to detect a change in the phase angle φ (1 wavelength is 3.1026 mm) of the 48.2888 GHz synthetic wave waveform from the phase change of the composite wave waveform of 0.8 MHz (1 wavelength is 375000 mm). If this change of 3.1026 mm is converted into a phase angle at 0.8 MHz, it corresponds to a phase angle of about 1 / 20,000. This means that a phase angle amplification effect of about 120,000 times occurred. Also, according to equation (15), the position determination accuracy is independent of the distance, so the distance variation within λ is determined with high accuracy (10 μm) regardless of whether the distance to the reflector is 1 m or 10 times the distance of 10 m. It turns out that it is possible. This indicates that the present invention can be applied to monitoring equipment such as heart motion in the medical field.

  Further, the resolution limit by the distance displacement measuring method of the pulse wave measuring apparatus of the present invention can be specifically estimated to be 8.6266 μm when the frequency difference is 100 MHz and 8.6264 μm when the frequency difference is 1 MHz. Therefore, it can be said that there is no difference in resolution, and this can be said that there is no problem with respect to resolution even when an oscillation circuit with poor frequency stability is used. Therefore, the pulse wave measuring device of the present invention can use a low-cost oscillation circuit with poor frequency stability.

Next, the distance displacement Δd in the distance displacement measuring method used in the pulse wave measuring apparatus of the present invention will be described. Focusing on the fact that there is “2πf ₂ τ” as a phase term in the above equation (11), this τ is rewritten using equation (5) as follows.
2πf ₂ τ = 2πf ₂ (2d / c) (17)
If N is an arbitrary integer and the wavelength corresponding to the frequency f ₂ is λ ₂ , then λ ₂ = c / f ₂ , and further d = N · λ ₂ + d ₁ , Equation (17) is It becomes like this.
2πf ₂ τ = 4πN + 4πf ₂ · d ₁ / c (18)
In the equation (18), 4πf ₂ · d ₁ / c is meaningful as a phase.
Similarly, for the phase term in equation (12), if M is an arbitrary integer and the wavelength corresponding to the frequency f ₁ is λ ₁ , then λ ₁ = c / f ₁ and d = M · λ ₁ Assuming + d ₂ , the expression corresponding to Expression (18) is as follows.
2πf ₂ τ = 4πM-4πf ₁ · d ₂ / c (19)
In the formula (19), -4πf ₁ · d ₂ / c is meaningful as the phase. Then, the phase difference φ between the first differential output waveform V _c1 represented by Expression (11) and the second differential output waveform V _c2 represented by Expression (12) is
φ = 4πf ₂ · d ₁ / c-(− 4πf ₁ · d ₂ / c)
= 4π (f ₂ · d ₁ / c + f ₁ · d ₂ / c) (20)
It becomes.

Next, as shown in FIG. 1, it is assumed that the object 50 is in a certain place (referred to as “state a” and indicated by reference numeral 50 a) and is displaced by a distance Δd. The state of the object 50b after the displacement is referred to as “state b”. When the phase difference φa in the state a and the phase difference φb in the state b are measured according to the equation (20), the result is as follows.
φa = 4π (f ₂ · d ₁ / c + f ₁ · d ₂ / c) (21)
φb = 4π [f ₂ · (d ₁ + Δd) / c + f ₁ · (d ₂ + Δd) / c] (22)
When the phase difference (Δφ = φb−φa) between φa and φb is obtained,
Δφ = 4π · Δd · (f ₁ + f ₂ ) / c (23)
Accordingly, the displacement Δd of the distance is obtained by using the phase difference Δφ and the first frequency f ₁ and the second frequency f ₂ .
Δd = Δφ / [4π · (f ₁ + f ₂ )] (24)
Can be obtained as

In Formula (24), when (f ₁ + f ₂ ) in the denominator increases, Δd corresponding to the same phase difference Δφ decreases. Therefore, the equation (24) shows that the distance displacement measurement method of the object 50 used in the present invention can measure the distance displacement of a small dimension by the same phase difference change. It can be said. This indicates that the displacement measurement resolution is improved in the method for measuring the displacement of the distance of the object 50 used in the present invention. On the other hand, since the conventional method uses (f ₁ −f ₂ ), the method for measuring the displacement of the distance of the object 50 using (f ₁ + f ₂ ) is the resolution of the displacement measurement. Can be said to have improved. Therefore, if the method for measuring the displacement of the distance of the object 50 used in the present invention is used, the measured value of the displacement of the distance of the object 50 can be obtained with high accuracy. By using the living body as the measurement object 50, the displacement of the living body surface due to the pulse wave can be measured in a non-contact manner as the displacement of the distance between the pulse wave measuring device and the object 50. Therefore, it is possible to obtain a pulse wave measurement device capable of performing pulse wave measurement with high accuracy in a non-contact manner with respect to the living body that is the measurement object 50.

In the distance displacement measuring method used in the pulse wave measuring device of the present invention, the following method can be used as a method for estimating the phase. That is, the above formula (9)
^{_{V c1 = [αA 2/2}} ] [cos (2πf 1 τ)
+ Cos {(2πf ₁ + 2πf ₁ ) t−2πf ₁ τ}
+ Cos {(2πf ₁ -2πf ₂ ) t + 2πf ₂ τ}
+ Cos {(2πf ₁ + 2πf ₂ ) t-2πf ₂ τ}]
... (9)
Is transformed by the trigonometric sum formula “cos α + cos β = 2 cos {(α + β) / 2} · cos {(α−β) / 2}”,
^{_{V c1 = [αA 2/2}} ] [cos (2πf 1 τ) + cos {2π (f 1 -f 2) t + 2πf 2 τ} + B · cos [2π {(3f 1 + f 2) / 2} t-2π {( f ₁ + f ₂ ) / 2} τ]] (9 ′)
It becomes.
Here, B corresponding to the amplitude is
B = 2 cos [2π {(f ₁ −f ₂ ) / 2} t−2π {(f ₁ −f ₂ ) / 2} τ]
Can be expressed as

Similarly, equation (10)
^{_{V c2 = [αA 2/2}} ] [cos (2πf 2 τ)
+ Cos {2π (f ₂ −f ₁ ) t + 2πf ₁ τ)}
+ Cos {2π (f ₂ + f ₁ ) t−2πf ₁ τ}
+ Cos {2π (f ₂ + f ₂ ) t−2πf ₂ τ)] (10)
Is transformed by the trigonometric sum formula “cos α + cos β = 2 cos {(α + β) / 2} · cos {(α−β) / 2}”,
^{_{V c2 = αA 2/2]}} [cos (2πf 2 τ) + cos {2π (f 2 -f 1) t + 2πf 1 τ} + B · cos [2π {(3f 2 + f 1) / 2} t-2π {(f ₁ + f ₂ ) / 2} τ]]
... (10 ')
It becomes.

Here, paying attention to the three items of the formula (10 ′),
B = 2 cos [2π {(f ₁ −f ₂ ) / 2} t−2π {(f ₁ −f ₂ ) / 2} τ]
If B is regarded as an amplitude, the frequency of the amplitude B is (f ₁ −f ₂ ) / 2, and since the maximum of the absolute value of B is a portion corresponding to a peak and a valley, the maximum value for one wavelength is There will be two places. That is, since two vibrations occur for one vibration, (f ₁ -f ₂ ) is (f ₁ -f ₂ ) twice (f ₁ -f ₂ ) / 2. By utilizing this fact, the amplitude also changes in accordance with the phase change from the maximum value to the minimum value and again to the maximum value of the synthesized wave waveform, so it can be said that the phase can be estimated from the fluctuation of the amplitude. .

  In the distance displacement measuring method used in the pulse wave measuring apparatus of the present invention, a distance displacement measuring method based on a phase difference caused by arbitrary electromagnetic wave irradiation can be used. For example, in the pulse wave measuring apparatus of the present invention, a method using a standing wave radar, a method using a quadrature detector, or the like can be used.

  The pulse wave measuring device of the present invention preferably has a configuration that prevents the occurrence of malfunction due to external electromagnetic waves. Specifically, in each configuration shown in FIG. 1 of the pulse wave measuring apparatus of the present invention, the range of A1 and A2, the range of B, or the range of C shown by dotted lines is made independent and placed inside the shield structure. It is preferable to do. By keeping a predetermined range in the shield structure, it is possible to prevent the occurrence of malfunction due to external electromagnetic waves. In addition, when making the said range into the independent shield structure, you may make it independent on a board | substrate, and you may isolate | separate from a board | substrate and modularize.

  Next, the pulse wave measurement by the pulse wave measuring device of the present invention will be specifically described. In the following example, the case where electromagnetic waves are microwaves will be described as an example.

  FIG. 1 shows a configuration of a pulse wave measurement device according to an embodiment of the present invention. The pulse wave measurement device directs the first antenna 12 and the second antenna 22 of the pulse wave measurement device to the measurement target 52 of biological vibration. The first electromagnetic wave 15 and the second electromagnetic wave 25 irradiated from the first antenna 12 and the second antenna 22 of this pulse wave measuring device detect the displacement of the distance due to the biological vibration of the measured part 52.

FIG. 4 shows the positional relationship between the first antenna 12 and the second antenna 22 of the pulse wave measuring device and the measured part 52 of biological vibration. Here, the beam spot radius r _A of the interference region (the portion where the first electromagnetic wave 15 and the second electromagnetic wave 25 overlap) in the measurement target 52 irradiated with the microwave is equal to the first electromagnetic wave 15 and the second electromagnetic wave 25. When the radiation beam width (angle of spread) is θ, it can be obtained by the following equation (24).
r _A = d _C tan θ−x (24)
Here, x indicates a half length of the distance between the first antenna 12 and the second antenna 22. D _C is the distance between the first antenna 12 and the second antenna 22 and the part to be measured 52.

Table 1 shows that the distance between the first antenna 12 and the second antenna 22 is 8 cm (x = 4 cm) and the microwave radiation beam width θ is 10 degrees and 20 degrees. The calculation result when the distance d _C is changed from 10 cm to 30 cm is shown. Where r _A shows a negative value, there is no beam spot in the interference region, so it is impossible to measure distance displacement.

Where a positive value is shown, there is a beam spot in the interference region, so that the distance displacement can be measured. However, when the radius r _A is increased, the beam spot in the interference region is increased, and thus the obtained information becomes average information over a wide area, and it is difficult to detect a clear biological vibration waveform.

  As an example, in detecting the aortic root, the lumen radius of the arterial blood vessel is about 1 cm. Therefore, a clearer detection of a pulse wave waveform is possible by setting the position of the measured portion 52 to about 30 cm from Table 1. It becomes possible. Further, the radiation beam width θ of the microwave is preferably θ such that the front gain of the antenna directivity is near 3 dB down (position where the power is halved). The optimization of the value of θ can be obtained while comparing with an actual measurement experiment. Since the antenna beam width θ is different when the radiation antennas are different, it is necessary to optimize the beam width θ.

The radius r _A of the portion where the first electromagnetic wave 15 and the second electromagnetic wave 25 overlap can be set to a radius r _A where θ is a half-value angle. It is preferable that the radius r _A for reliably performing the measurement of the biological vibration is not more than three times the diameter φ _t of the blood vessel that is different for each measurement site as shown below. By the radius r _A is less than 3 times the diameter phi _t, because the measurement can be performed with high accuracy. Diameter φ _t of the blood vessels of each measurement site, the aorta causing branch in the φ _t = 20~30mm, in the abdominal aorta φ _t = 14~20mm, in the iliac artery φ _t = 6~10mm, in the upper arm of the artery φ _t = 5 to 8 mm, φ _t = 2 to 4 mm (specifically 3 mm) for the arteries of the lower arm or ankle, and φ _t = 0.2 to 0.5 mm for arterioles.

  Next, the first reflected wave 16 that is the reflected electromagnetic wave from the object 50 of the first electromagnetic wave 15 and the second reflected wave 26 that is the reflected electromagnetic wave from the object 50 of the second electromagnetic wave 25 are received by the reflected synthetic wave receiving unit. A reflected composite wave that is a composite wave is received. In the example illustrated in FIG. 1, a reflected combined wave that is a combined wave of the first reflected wave 16 and the second reflected wave 26 is received by the first antenna 12 and the second antenna 22, respectively.

  In addition, the reflected synthetic wave receiving unit for receiving the reflected synthetic wave of the first electromagnetic wave 15 and the second electromagnetic wave 25 uses a single antenna, and the single antenna has a function of both electromagnetic wave transmission and reception. It is also possible to configure. In this case, a single antenna is connected to two multipliers (first multiplier and first multiplier) via the power combiner. The power combiner functions as a power combiner in the transmission direction and functions as a power distributor in the receive direction. Since the power combiner has an isolation of 30 dB or more, the waveforms of the two mixers (the first multiplier and the first multiplier) can be prevented from leaking from each other. That is, it can be said that the use of a power combiner has substantially the same effect as changing the arrangement angle of two antennas.

  In the example shown in FIG. 1, the reflected synthesized wave waveform of the reflected synthesized wave received by the first antenna 12 is introduced into the mixer 14 (first multiplication unit) and multiplied by the first frequency waveform. The reflected synthesized wave waveform of the reflected synthesized wave received by the second antenna 22 is introduced into the mixer 24 (second multiplication unit), multiplied by the second frequency waveform, and output from the mixer 14 as the first difference. An output waveform is obtained. The first frequency waveform and the second frequency waveform are respectively introduced from the first frequency waveform generator 13 and the second frequency waveform generator 23 to the mixer 24 (first multiplier) and the mixer 24 (second multiplier). A second differential output waveform is obtained as an output from the mixer 24.

  Next, in the example shown in FIG. 1, a high-pass filter and a band-pass filter (shown as “HPF / BPF” in FIG. 1, also referred to as “frequency selection unit”) from the mixer 14 (first multiplication unit). A desired frequency component is selected from the first differential output waveform that is Similarly, a desired frequency component is selected from the second differential output waveform, which is an output from the mixer 24 (second multiplication unit), using a high-pass filter and a band-pass filter. Desired frequency components of the first frequency waveform and the second frequency waveform are introduced into and compared with a phase comparison unit 29 such as a phase difference meter, for example, so that the phase difference φA of Expression (13) or Expression (23) The phase difference Δφ shown in FIG. At this time, the phase comparison unit 29 compares the phase by amplifying the first frequency waveform and the second frequency waveform input to the phase comparison unit 29 with a predetermined gain by the variable gain amplification units 18 and 28. More accurately and easily. The variable gain amplifying units 18 and 28 are circuits for amplifying signals, and are configured so that the gain of amplification can be changed.

  Next, in the example illustrated in FIG. 1, the displacement measurement unit 31 may obtain the measurement result of the displacement of the distance of the object 50 based on the phase difference between the first differential output waveform and the second differential output waveform. it can. For example, a general-purpose computer such as a personal computer can be used to calculate the displacement of the distance of the object 50 from the phase difference. Specifically, high-frequency components are removed from the output signal from the phase comparison unit 29 by a low-pass filter, and information on the phase difference changed to a digital signal can be obtained by an analog-digital converter (ADC). In the displacement measuring unit 31, based on the information on the phase difference, the result of the measurement of the displacement of the distance of the object 50, that is, the displacement dA or Δd of the distance of the object 50 shown by the equation (15) or the equation (24). Can be obtained. The output signal from the phase comparison unit 29 is preferably processed by the waveform processing unit 30.

  Further, the displacement measuring unit 31 may include an extra-pulse wave displacement removing unit that removes a displacement based on at least one of respiration, body motion, and movement of the pulse wave measuring device included in the distance displacement. In general, the waveform measured by the displacement measuring unit 31 shows a waveform in which respiration, body movement, and the like are superimposed in addition to the pulse wave. If the pulse wave measurement is affected by the displacement of the distance due to respiration, body movement, movement of the pulse wave measurement device, etc., the pulse wave measurement may not be performed accurately. Therefore, the accuracy of pulse wave measurement can be improved by removing the displacement based on at least one of respiration, body motion, and movement of the pulse wave measuring device included in the distance displacement.

  Further, the displacement measuring unit 31 can obtain the overall tendency of the pulse wave by continuously obtaining the measurement result of the displacement of the distance of the object 50, and can reliably perform the pulse wave measurement. it can.

  Next, in the example illustrated in FIG. 1, based on the measurement result of the displacement of the distance of the object 50 obtained by the displacement measurement unit 31 (displacement dA or Δd of the distance of the object 50), the index calculation unit 32 performs the measurement. The calculation result of the index relating to the pulse wave can be obtained. The index calculation unit 32 is a part configured to obtain the calculation result of the index related to the pulse wave using the measurement result of the displacement of the distance of the object 50 obtained by the displacement measurement unit 31. For the index calculation, for example, a general-purpose computer such as a personal computer can be used. By providing the index calculation unit 32, it is possible to reliably calculate the index related to the pulse wave. Examples of the index relating to the pulse wave include arterial stiffness, an estimated value of the pulse wave velocity (PWV), AI (Augmentation Index), and CAVI (Cardio Ankle Vascular Index). As described above, the pulse wave velocity (PWV) can be obtained by equation (101). Moreover, AI (Augmentation Index) can be calculated | required by Formula (101).

  Next, in the example shown in FIG. 1, comprehensive diagnosis data such as arteriosclerosis is provided by the diagnosis unit 34 based on the analysis of the detailed shape change of the index and the pulse wave waveform calculated by the index calculation unit 32. be able to. For the diagnosis by the diagnosis unit 34, for example, a general-purpose computer such as a personal computer can be used.

  Further, the pulse wave measuring device of the present invention sets the determination result corresponding to the preset pattern, the displacement pattern of the distance of the object 50 measured by the displacement measuring unit 31, and the preset pattern. And a determination unit that obtains a determination result based on the comparison result. The determination unit compares the displacement pattern of the distance of the object 50 measured by the displacement measurement unit 31 with a preset pattern, and obtains the result of determination of the presence or absence of a disease state, etc. The result of the determination can be easily obtained. Specifically, the judgment results are normal, arteriosclerosis, hypertension / hyperlipidemia, obstructive hypertrophic cardiomyopathy, dilated cardiomyopathy, aortic regurgitation, hyperthyroidism, obstructive arteriosclerosis It can be related to at least one of symptom and diabetes. By using the result of determination by the determination unit, the diagnosis by the diagnosis unit 34 can be made more accurate.

  In the example shown in FIG. 1, the pulse wave measuring device of the present invention displays the result together with the pulse wave information in which the displacement of the distance of the object 50 measured by the displacement measuring unit 31 is recorded for a predetermined time at a predetermined sampling rate. Storage means 36 for storing the information in association is provided. The storage means 36 can be connected to a general-purpose computer such as a personal computer such as a hard disk drive, CD drive, DVD drive, and various memories, and is a known storage means 36 that can store pulse wave information electronically. Can be used. The pulse wave measuring apparatus of the present invention includes the storage means 36 and stores the results in association with each other, thereby easily making the pulse wave pattern (change in the displacement of the measured object 50 with time) itself as pulse wave information. Since detailed examination can be performed, a doctor or the like can easily and accurately analyze a more detailed medical condition.

  Further, in the example shown in FIG. 1, the pulse wave measuring device of the present invention includes a notifying unit 38. It is preferable that the notification means 38 sets the notification mode in the case of a measurement abnormality for which a result is not obtained and the notification mode for the measurement result in a case where a result is obtained as different notification modes. When the pulse wave measuring device of the present invention includes the notifying means 38, remeasurement by a doctor or the like can be reliably performed in the case of a measurement abnormality in which a result cannot be obtained. Further, when the result is obtained, particularly when the medical condition is not normal, it is possible to ensure that the doctor or the like copes without overlooking it.

  Moreover, the pulse wave measuring device of the present invention can include a plurality of the above-described pulse wave measuring devices. In other words, a plurality of pulse wave measuring devices can simultaneously measure positions corresponding to blood vessels of different parts of the same person, and an index relating to pulse waves based on a time lag of a result of measuring displacement at a plurality of distances. Can be calculated. Moreover, it is preferable to fix the target object 50 in the case of a measurement. Therefore, the pulse wave measuring device of the present invention can include an object 50 fixing means selected from a bed, a chair, and the like.

Example 1
FIG. 5 shows a system configuration diagram of the pulse wave measuring apparatus according to the first embodiment of the present invention. In the system configuration diagram of the pulse wave measuring device of FIG. 5, a display (1B) and an operation keyboard (1D) for displaying various information of the main body are integrally provided, and a CPU (Central Processing Unit) (70) is provided. ), An information processing device (1) such as a personal computer and a smartphone with a built-in memory (11), a memory card (2) detachably attached to the information processing device (1), and an information processing device (1). A printer (4), an AD converter (51) and a microwave minute displacement sensor (20) are shown.

  The microwave minute displacement sensor (20) detects the biological vibration of the measured part 52 in a non-contact manner, and the detected biological vibration is converted into digital information by the AD converter (51) to the CPU (70). Given.

  The operation keyboard (1D) inputs information and instructions to the information processing apparatus (1) by an external operation. The memory card (2) is attached to the information processing apparatus (1), and information described therein is accessed by CPU control of the information processing apparatus (1).

  Among biological vibrations, in particular, the aortic pulse wave, which is the vibration of the aortic blood vessel, is superposed with a respiratory component having a larger amplitude than the pulse wave component, so complicated waveform processing such as frequency analysis is required. The pulse wave measurement procedure using the pulse wave measuring device of the present invention shown in FIG. 6 and the examination clothes printed on arterial blood vessels and the like enable efficient and detailed acquisition of pulse wave waveforms.

The pulse wave measurement procedure shown in FIG. 6 is as follows.
1) In order to relax the subject, it will be completed in a few minutes without the purpose and pain of the measurement, and it will be communicated that it is okay to wear clothes.
2) Mark the measurement site with laser light (because the pulse wave waveform is different in the carotid artery, ascending artery, subclavian artery, brachial artery, radial artery, etc.).
3) Monitor normal breathing (adjust the distance with reference to the PSD (position detection element) output so that the phase is maximized).
4) After checking the waveform when breathing greatly, ask the measurer to stop breathing for a few seconds (repeat for a few seconds and repeat normal breathing several times, and if a good waveform is received) , Record pulse wave waveform data and PSD distance meter (position detection element) data).
5) Tell the subject that the measurement is complete.

  FIG. 8 shows a waveform in which respiration and a pulse wave are superimposed. In FIG. 8, a waveform having a large amplitude with a period of 3 to 4 seconds is respiration, and a waveform having a small period of about 1 second is a pulse wave.

  FIG. 9 shows a detailed pulse wave waveform acquired by the above pulse wave measurement procedure. It can be seen that this pulse waveform shows in detail the ejection wave from the heart and the reflected wave from the peripheral blood vessel corresponding to arteriosclerosis of the central blood vessel.

  In the said Example 1, the pulse-wave measuring apparatus of this invention can also be installed in beddings, such as a bed.

  In the first embodiment, two microwave transmitters / receivers are provided as the microwave minute displacement sensor (20). However, three or more microwave transmitters / receivers may be used. A standing wave radar or the like may be used.

  In the first embodiment, the microwave of 24 GHz is used as the radio wave. However, the radio wave is not limited to this as long as the radio wave can detect the displacement. For example, a microwave other than 24 GHz may be used.

  In the first embodiment, the measurement target 52 is irradiated with microwaves, but may be irradiated to a place where a displacement occurs inside the human body without surface vibration.

  In the first embodiment, when the emergency waveform is identified from the comparison waveform by means of neural network processing or the like and compared with the biological vibration waveform stored in advance, the alarm device (60) is voiced. The alarm may be issued by a method other than voice. For example, a warning may be displayed on the monitor. Both voice and display can be used. Alternatively, it is also possible to use a wireless communication device to issue an alarm from the alarm device (60) to the outside by wireless communication when an operation command for the alarm device (60) is issued from the CPU (70). . In this case, a configuration in which the alarm is transmitted to the information center and an ambulance is arranged from the information center that has received the alarm is also possible.

  The pulse wave measuring device of the present invention may be configured not to use the alarm device (60). For example, the pulse wave measurement device can be used as a simple analysis device.

  As described above, according to the present embodiment, it is possible to provide a device with improved measurement accuracy compared to conventional devices in a biological vibration detection device by emitting a microwave to a human body and receiving a reflected wave. it can.

(Example 2)
In FIG. 10, the schematic diagram of the system configuration | structure of the pulse-wave measuring apparatus of Example 2 is shown. In FIG. 10, “LASER” indicates a laser, and “PSD” indicates a position detection sensor.

As shown in FIG. 10, when two measurement frequencies (two high frequencies, f ₁ and f ₂ ) are irradiated to a measurement site such as the aortic root and the femoral artery, the distance between the moving object detection sensor (antenna) and the measurement site d can be obtained by the following equation (100) with reference to equation (15).

d = cφ / {4π (f ₁ + f ₂ )} (100)

Here, c is the speed of light, f ₁ and f ₂ are emission frequencies from two high-frequency (two-frequency) moving body detection sensors (antennas), and the phase angle φ is a composite waveform (f ₁ -f ₂ and f ₂ −f ₁ ), which is given by the phase difference of two frequencies.

As a specific example, when f ₁ = 24.1498 GHz and f ₂ = 24.1490 GHz, if c = 3 × 10 ¹¹ mm / sec in equation (100), this corresponds to the case where the phase difference is φ = 2π. The maximum measurable distance λ of d is
λ = 3 × 10 ¹¹ /(2×48.2988×10 ⁹ ) = 3.1026 mm.

Therefore, the distance d to the reflector is obtained from the phase difference φ of the beat waveform of f ₁ −f ₂ = 0.8 MHz. If the phase difference φ of the beat waveform of f ₁ −f ₂ = 0.8 MHz is detected with 1 ° accuracy, the distance d = 0. 060 mm corresponding to the phase difference φ = 1 ° of f ₁ + f ₂ , that is, It shows that it can be determined with an accuracy of 8.6 μm.

  FIG. 1 shows a block diagram of a pulse wave waveform measurement system of the pulse wave measurement device of the present invention used in the second embodiment. As shown in FIG. 1, the waveforms from the two microwave moving body detection sensors are input to a phase difference meter (phase comparison unit 29) that detects the respective phase differences, and the phase differences are input by an analog-digital converter (ADC). A / D converted, processed and recorded by the information processing apparatus. Note that the information processing apparatus can appropriately include a waveform processing unit 30, a displacement measurement unit 31, an index calculation unit 32, a diagnosis unit 34, a storage unit 36, a notification unit 38, and the like.

  As a feature of the present apparatus used in the second embodiment, the measurement accuracy of the distance d by the above-described equation (100) is independent of the distance between the moving object detection sensor and the measurement site. This means that if the waveform intensity is sufficient even at a long distance, the distance d can be measured with high accuracy, but the following problems may occur.

  As can be seen from FIG. 1, the beam spot (the size of the portion to be measured 52) where the microwave interferes varies depending on the distance between the moving body detection sensor and the measurement site. If the distance is increased and the beam spot is increased, the detection range of the measurement site is expanded, and the position variation as the average value is detected. This means that a clear pulse waveform cannot be detected.

  On the other hand, since the pulse wave waveform varies depending on the measurement site such as the peripheral artery waveform and the aortic waveform, it is necessary to point the measurement site. In order to solve this problem, a system to which a laser (LASER) and a position detection element (PSD: Position Sensitive Detector) are added can be used. This system makes it possible to irradiate microwaves at the optimum point and with the optimum beam spot. Non-contact reflected pressure waves from peripheral blood vessels (the main part of reflection is from the abdominal aorta to the left and right descending aortic bifurcations) Vivid pulse waveform data including a composite wave in which the driving pressure wave interferes with the vicinity) can be acquired. Specifically, when the center of the beam spot S where the microwave interferes is indicated by a laser, and the distance measurement from 20 cm to 150 cm is possible by the position detection element (PSD), this laser and the position detection element By irradiating the optimum point with microwaves using (PSD), it was possible to obtain clear pulse waveform data as shown in FIG.

  In Example 2, the heart rate waveform and the respiratory waveform were measured as follows using the above-described apparatus. That is, in the actual measurement, data was acquired by irradiating a microwave (high frequency) toward the aorta starting portion about 30 cm from the moving body detection sensor with a laser and a position detection element (PSD).

  FIG. 11 shows data in which the respiration and pulse wave of an adult woman (in her 50s) lying on the bed are mixed. The horizontal axis represents elapsed time (in 0.01 sec units, for example, “1000” represents 10 seconds), and the vertical axis represents the phase difference in voltage (mV). The portions (4 sec to 6 sec) and (12 sec to 15 sec) where the change is large (about 1000 mV) in FIG. 11 and about 2 sec to 3 sec are respiratory components generated because the subject took a deep breath. When analyzing the respiratory waveform, the phase exceeds 180 degrees and is in the opposite phase at the 5 sec and 13 sec locations where the phase difference greatly fluctuates due to respiration and in the vicinity of the phase difference output voltage value 1700 mV.

  In addition, in places (7 sec to 11 sec) and (16 sec to 20 sec) where the change is small (about 200 mV), the patient intentionally stops breathing for 4 to 5 seconds, and the waveform in the apnea state is obtained. It was measured. This data shows a waveform of a pulse wave component corresponding to a heart rate repeated at a period of about 1 second.

  FIG. 12 is an enlarged view of only the portion (6 sec to 10 sec) of the pulse wave waveform obtained by measuring the waveform in an apnea state by having the subject intentionally stop breathing for 4 to 5 seconds in FIG. However, it is clear from FIG. 12 that there are four pulse wave waveforms corresponding to the heart rate with a period of about 1 second.

  FIG. 13 is an enlarged view of a part of FIG. 12 (7.2 sec to 8.4 sec). FIG. 13 shows a waveform very similar to the pulse waveform of the carotid artery obtained by applying a pulse wave pickup for detecting pressure fluctuations to the neck.

  From this, the pulse wave waveform of the aortic root that could not be measured without inserting an ultra-small pressure sensor into the arterial blood vessel with a catheter can be contacted and worn without contact by the device of the present invention. It became clear that it could be measured.

  FIG. 14 shows a pulse waveform of an adult male (60s). Four pulse waveforms each having a period of about 0.7 seconds are shown in a row.

  FIG. 15 is an enlarged view of a part (9.1 sec to 9.9 sec) of FIG. FIG. 15 shows a waveform very similar to the pulse waveform of the carotid artery obtained by applying a pulse wave pickup for detecting pressure fluctuation to the neck.

  The first peak of the pulse wave waveform indicates that when blood is sent to the aorta due to contraction of the left ventricle, an aortic root pressure wave is generated and the blood pressure at the aortic root is increased. This is the systolic front component and the driving pressure wave is detected. After this, the blood pressure should decrease, but the blood pressure rises again to form the second peak. This is a posterior systolic component and indicates that a composite wave in which a reflected pressure wave from a peripheral blood vessel and a driving pressure wave interfere with each other is detected.

  Comparing the aortic root pulse waveform of the adult female (50s) in FIG. 13 with the aortic root pulse waveform of the adult male (60s) in FIG. It can be seen that the second peak is larger than the first peak of the anterior systolic component.

  The ratio of the peak of the first systolic component (first) and the second systolic component (second) is called AI (Augmentation Index), and the driving pressure from the heart (ejection pressure) It is the ratio of the reflection pressure wave (reflection pressure) that propagated through and returned from the periphery. Considering this, since the arterial pulse wave of males in their 60s has a fast reflected wave velocity from the periphery, a composite wave in which the driving pressure wave and the reflected wave interfere with each other, and the second synthesis exceeds the first driving pressure wave. It is thought that it became. Therefore, it is presumed that this subject has advanced arteriosclerosis. Although we did not post data, we measured respiration and pulse waveform from a distance of about 30 cm forward while sitting on a chair, and confirmed that similar respiration waveform and pulse waveform data were obtained. .

  As described above, it has been clarified that if the pulse wave measuring device of the present invention is used, breathing and pulse wave waveforms can be measured while sitting on a chair while wearing clothes. In addition, it is considered that noise caused by moving the body can be removed by a technique such as frequency analysis.

  In Example 2, the pulse wave measuring device of the present invention was prototyped. In addition, the pulse wave measuring device was used to acquire data through actual experiments and confirm its usefulness.

Problems with conventional non-contact pulse wave measurement using microwaves include the following.
1) The position of the portion irradiated with the microwave (beam spot S where the microwave interferes) cannot be visually observed.
2) There is a problem that the size of the beam spot S changes depending on the distance between the moving body detection sensor and the measurement site. That is, since the beam spot S is small at a short distance, the interference signal intensity is weak. In the worst case, measurement is impossible when the beam spot S in the interference region does not exist. In addition, the beam spot S becomes large at a long distance, so that the average data of a wide area is obtained, and a clear pulse wave waveform cannot be detected.

  These problems were solved by using a system in which a laser and a position detection element (PSD) were added as described above. This makes it possible to irradiate the microwave with the optimal beam spot at the optimal beam spot, and non-contact reflection pressure waves from peripheral blood vessels (the main part of reflection is from the abdominal aorta to the left and right descending aortic bifurcations) ) And the pulse wave waveform data including the synthesized wave interfering with the driving pressure wave.

  The pulse wave measurement using the pulse wave measuring device of the present invention is different from the conventional detection of the respiratory rate and heart rate by microwaves. Instead of detecting the heart rate as an AC component, the fluctuation / angle data is used as DC voltage data. The extracted pulse waveform itself can be detected, and comprehensive diagnosis data such as arteriosclerosis can be provided from the detailed shape change of the pulse waveform. Furthermore, since the method of Example 2 can directly measure physical quantities (respiration waveform and pulse waveform) while wearing clothes, it can be applied to screening in the medical field.

(Example 3)
As Example 3, measurement of pulse wave velocity (PWV) and AI (Augmentation Index) using the pulse wave measuring device of the present invention was performed as follows.

  As a method for evaluating the stiffness of an artery due to arteriosclerosis that progresses with age, there are a pulse wave velocity (PWV) and an AI (Augmentation Index). PWV is used to evaluate segmental arterial stiffness, and AI is used to evaluate systemic arterial stiffness. Conventionally, in order to determine the degree of arteriosclerosis caused by hyperlipidemia or the like, blood vessel mechanical data corresponding to blood vessel hardness has been measured. In particular, the pulse wave velocity (PWV) measurement method has been used as a method for noninvasively measuring the hardness of a blood vessel. This PWV measurement is based on the pulse wave propagation time between two points (carotid-femoral artery: cf [carotid-femoral]) or (brachial-ankle artery: ba [brachial-ankle]) and the distance between the two points. The pulse wave velocity is obtained and is an evaluation index for arteriosclerosis. However, the above-described PWV measurement method requires expensive medical equipment such as attaching a plurality of vibration sensors to the body of the subject. In the third embodiment, an algorithm for obtaining AI and PWV values from microwave pulse wave data will be described. This algorithm allows AI and PWV values to be obtained from pulse wave data at a single location, so that patients and elderly people can be monitored for health care and health monitoring and screening in the field of preventive medicine. Because it can be done in, it is considered convenient. Hereinafter, the measurement result of Example 3 will be described in detail.

  As shown in FIG. 7, a primary pulse propagates along the artery wall toward the periphery as the heart beats. In addition, when a pulse wave collides with a bifurcation point such as the left and right common iliac artery (Iliac aorta) bifurcation point (descending aortic bifurcation) or femoral artery from the abdominal aorta, it becomes a reflected wave and propagates toward the opposite heart direction . The ratio of the reflected wave to the pulse wave is called AI (Augmentation Index), and an increase in AI means that the hardening of the blood vessel proceeds.

In FIG. 7, S is the average cross-sectional area (cm ² ) of the arterial lumen, and PWV (m / sec) indicates the average pulse wave propagation velocity in the carotid artery, thoracic artery, abdominal artery, femoral artery, and the like. .

  FIG. 3 shows the pulse wave measurement result between two points (L = 20 cm) of an adult woman in her 50s. In the measurement, the measurement was performed at the origin of the aorta as the point A and the descending aorta as the point B in a state of lying on the bed at a position about 30 cm away from the sensor. The horizontal axis represents elapsed time, and the vertical axis represents phase difference. In the actual measurement, the subject took a deep breath and stopped breathing, and the measurement was performed for several seconds in an apnea state. Actually, since the distance between the two points is as short as 20 cm, measurement was performed by setting the polarization planes of the antennas to be orthogonal to each other in order to avoid interference of reflected waveforms from each part (point A and point B).

  It can be seen that the pulse wave at the gray point B (descending aorta) in FIG. 3 is delayed with respect to the pulse wave at the black point A (aortic origin: black). According to FIG. 3, the pulse wave propagation time Δt from the point A to the point B is about 0.05 seconds, and when the distance L between the points A and B is 20 cm, the pulse wave velocity (PWV) is PWV. = 20 cm / 0.05 sec = 4 m / sec.

The pulse wave velocity (PWV) can be obtained by the following equation (101).
PWV = L / Δt (101)

  Here, Δt is a propagation time during which the pulse wave propagates from point A to point B by a distance L.

  FIG. 16 is an enlarged view of the aortic origin and descending aortic wave waveform portion (7 sec to 9 sec) in FIG. When attention is paid to the pulse wave at the origin of the black aorta in FIG. 16, the first peak is the ejection pulse from the heart (Primary pulse), and the second peak is the reflected wave from the descending aortic bifurcation. The second peak represents Harmonics. Here, focusing on the reflected wave from the descending aortic bifurcation of the second peak and the harmonics of the third peak, the black aortic origin pulse waveform is more gray than the gray descending aortic waveform. It can be seen that the arrival time of the reflected wave is delayed.

  In order to explain this seemingly contradictory phenomenon, it will be described in detail below with reference to FIG.

  FIG. 17 shows a positional relationship in which two microwave minute displacement sensors (Sensor 1 and Sensor 2) are arranged at a distance L1, and the distance from Sensor 2 to the descending aortic bifurcation is assumed to be L2. As is apparent from FIG. 17, the ejection wave # 1 from the heart, which is the first peak, is detected by Sensor 2 with a delay of t1 that propagates through L1. Thereafter, each sensor is reached as reflection # 2 from its descending aortic bifurcation at distance L2 and its harmonics # 3. It is clear that the time for the reflected waves # 2 and # 3 to reach the sensor is shorter because the descending aortic bifurcation of Sensor2 is closer to L1 than Sensor1. For the above reason, it is possible to explain that the arrival time of the reflected wave is delayed in the black aortic origin pulse waveform than in the gray descending aorta waveform in the second and third peaks. is there.

  In addition, it seems that the 2nd peak which is reflected wave # 2 from the descending aortic bifurcation part of Sensor2 is disappearing, because the sensor2 and the descending aortic bifurcation part are close to each other, it becomes a composite wave with the 1st peak. It is in a state that cannot be identified. This can be understood from the fact that the pulse width of the first peak is wide.

  In order to examine the validity of the above-described concept, when calculating the pulse wave velocity only from the pulse wave data of the black aortic origin in FIG. 16, the first peak and the second peak from FIG. Is obtained as 0.15 sec. This time difference is the time required to propagate the reciprocal distance 2 × (L1 + L2) from the aortic origin to the descending aortic bifurcation. Here, assuming that the distance L between the aortic origin and the descending aortic bifurcation is 0.39 m, the reciprocating distance 2L is 0.78 m. Therefore, PWV is obtained as 0.78 / 0.15 to 5.2 m / sec from the equation (101). This value is larger than the value (4 m / sec) obtained from the time difference between the two points (A, B). From FIG. 7, since the PWV of the abdominal artery is 7 m / sec or more, 5.2 m / sec is considered to indicate the speed of PWV as an average value of the aortic origin and the abdominal artery.

  Next, AI and PWV are calculated. FIG. 18 shows a pulse waveform at the aortic root of an adult woman in her 50s.

  FIG. 19 is an enlarged view of a part (7.2 sec to 8.4 sec) of FIG.

  From FIG. 19, the time difference Δt between the first peak # 1 and the second peak # 2 is found to be 0.12 sec. This time difference is the time required to propagate the reciprocal distance 2 × (L1 + L2) from the aortic origin to the descending aortic bifurcation. Here, assuming that the distance L from the aortic origin to the descending aortic bifurcation is 0.39 m, the reciprocating distance 2L can be assumed to be 0.78 m. Therefore, from the equation (101), the pulse wave velocity is obtained from 0.78 / 0.12 to 6.5 m / sec.

  FIG. 20 shows a pulse waveform at the aortic root of an adult male in his 60s.

  From FIG. 21 in which a part of FIG. 20 (9.1 sec to 9.9 sec) is enlarged, the pulse wave propagation time Δt at points # 1 and # 2 is about 0.127 seconds, and the round trip distance 2L is 0.78 m. Then, from equation (1), the pulse wave velocity (PWV) is calculated as V = 0.78 m / 0.127 sec = 6.1 m / sec.

Further, in the pulse wave waveform of FIG. 21, the ratio AI between the peak of the systolic anterior component P1 (first) and the systolic posterior component P2 (second) is obtained by the following equation.
AI = ΔP / PP (102)
Here, ΔP is (P2−P1), and PP is represented by the maximum value of P1 and P2.

AI (Augmentation Index) is the ratio between the drive pressure from the heart (ejection pressure) and the reflected pressure wave that propagates in the blood vessel and reflects back from the periphery. Considering this, the AI value for men in their 60s is
AI = (175-110) /175=37.7%
Is required.

Similarly, the AI value of the adult female (50s) in FIG.
AI = (190−220) /220=−13.6%
Is required.

  In the conventional measurement of the pulse wave velocity PWV, two measuring devices are set between two measurement parts A and B, and the propagation time difference of the pulse wave waveform is measured. For this reason, the characteristics of the two measuring instruments must be the same, and care must be taken in setting the interval and direction of the measuring instruments.

  The pulse wave measuring device of the present invention succeeded for the first time in non-contact detection of the pulse wave waveform of the artery, and how the combined wave of the ejection wave from the heart and the reflected wave from the peripheral artery is time-sequentially. The time when the pulse wave collides with the descending aortic bifurcation was obtained from a simple model. As a result, PWV could be obtained from the arrival time of the reflected wave of one pulse wave data instead of the data between two points. Conventionally, since the pulse waveform of the aorta could not be directly detected, there have been no successful examples so far. Of course, the AI value can also be calculated at the same time.

  If the measurement algorithm of the pulse wave measuring device of the present invention is used, it is considered that it is an advantage that both values of AI and PWV can be obtained from pulse wave data at one place.

Example 4
In FIG. 22, the outline | summary of the pulse-wave measurement system used for Example 4 is shown. As shown in FIG. 22, two sets of microwave micro displacement sensors 40a and 40b having a frequency (f ₁ , f ₂ ) are irradiated to a measurement site (for example, heart or posterior tibial artery and ankle artery) separated by a distance L. In this case, the pulse wave velocity (PWV) at which the pulse wave propagates through the distance L can be obtained by the following equation (101).
V = L / Δt (101)
Here, Δt is the time for the pulse wave to propagate from the point A to the point B by the distance L.

  FIG. 24 shows a state in which the position A and the point B of the measured part are measured by the microwave minute displacement sensors 40a and 40b. The microwave minute displacement sensors 40a and 40b have the same configuration as the antennas 12 and 22 shown in FIG.

  As shown in FIG. 22, the phase difference data (pulse waveform) measured at the positions A and B where the two sets of two-frequency CW modules are arranged are converted into analog digital signals of the microwave micro displacement sensors 40a and 40b. After AD conversion by a converter (ADC), it is input to the information processing device (1). The information processing apparatus can obtain the delay time Δt of the pulse waveform at points A and B.

  FIG. 23 shows the pulse wave measurement result between two points (L = 57 cm) of an adult woman in her 50s. In the measurement, the measurement was performed at the aortic root as point A and at the femoral artery as point B in a supine position at a position about 30 cm away from the moving body detection sensor on the bed. The horizontal axis represents elapsed time, and the vertical axis represents phase difference. In the actual measurement, the subject took a deep breath and then stopped breathing, measured for a few seconds in an apnea state, and then repeated deep breathing and respiratory stop again. When attention is paid to the data in the apnea state of FIG. 23, the pulse wave at the gray point B (femoral artery) is delayed in time from the pulse wave at the black point A (aortic origin: black). I understand. That is, the same peak is detected with a time shift at the points A and B.

24 and 25 are enlarged views of the pulse waveform portions (5 sec to 10 sec and 15 sec to 20 sec) of the origin of the aorta and the femoral artery measured in the apnea state in FIG. 24 and 25, if the pulse wave propagation time Δt from the point A to the point B is about 0.145 seconds and the distance L between the point A and the point B is about 57 cm, the equation (101) The pulse wave velocity (PWV) is
PWV = 57cm / 0.145sec = 393cm / sec
Is calculated.

  FIG. 26 shows pulse wave waveforms between two points (L = 20 cm), an aortic root (point A) and a descending aorta (point B) in an adult female in their 50s. Actually, since the distance between the two points is as short as 20 cm, measurement was performed by setting the polarization planes of the antennas to be orthogonal to each other in order to avoid interference of reflected waveforms from each part (point A and point B).

From the figure, assuming that the pulse wave propagation time Δt at points A and B is about 0.05 seconds and the distance L between A and B is about 20 cm, from equation (101), the pulse wave velocity (PWV) is
V = 20cm / 0.05sec = 400cm / sec
Is calculated.

  In the fourth embodiment, the pulse wave velocity (PWV) sensor has been described as an application of the two-frequency CW short-range measurement algorithm. In addition, we obtained data through actual experiments and verified its usefulness.

  In the conventional PWV measurement, the pulse wave propagation time was measured by pressing the pressure sensor between the carotid artery and femoral artery (cf: carotid-femoral) or between the brachial artery and ankle artery (ba: brachial-ankle). . However, as a drawback, it is necessary to expose the measurement site, and some technique is required to record the waveform. Further, since the measurement site includes the peripheral artery, the pulse wave waveforms between the measurement sites A and B are different, and it is necessary to devise for calculating the PWV propagation time difference, making it difficult to measure with high accuracy. Furthermore, since the peripheral arteries are included, aortic stiffness is not directly reflected, and only information as an average value of the aorta and the peripheral arteries can be acquired.

  In pulse wave measurement using the pulse wave measuring apparatus of the present invention, interference of reflected waves from the measurement site can be avoided if the polarization planes of the antennas are set to be orthogonal to each other. This enables measurement at a relatively short distance (L = 20 cm) unlike conventional PWV measuring instruments, such as at the aorta (aortic origin (point A) and descending aorta (point B (B))). It is possible to obtain direct information on aortic sclerosis from the measurement, and since it can be measured without contact and while wearing clothes, it can be applied to screening such as health care and monitoring of health conditions.

12 First antenna (first electromagnetic wave oscillator)
13 First frequency waveform generator 14 Mixer (first multiplier)
15 First electromagnetic wave 16 First reflected wave 18 Variable gain amplification part 22 Second antenna (second electromagnetic wave oscillation part)
23 Second frequency waveform generator 24 Mixer (second multiplier)
25 Second electromagnetic wave 26 Second reflected wave 28 Variable gain amplification unit 29 Phase comparison unit 30 Waveform processing unit 31 Displacement measurement unit 32 Index calculation unit 34 Diagnosis unit 36 Storage unit 38 Notification unit 40, 40a, 40b Microwave micro displacement sensor 50 , 50a, 50b Object 52 Measured part

Claims (22)

Irradiate the object with the first electromagnetic wave of the first frequency,
Irradiate the object with a second electromagnetic wave having a second frequency different from the first frequency,
Receiving a reflected composite wave that is a composite wave of a first reflected wave that is a reflected electromagnetic wave from the object of the first electromagnetic wave and a second reflected wave that is a reflected electromagnetic wave from the object of the second electromagnetic wave;
By multiplying the reflected composite waveform and the first frequency waveform of the first frequency to obtain the first differential output waveform,
Multiplying the reflected composite waveform and the second frequency waveform of the second frequency to obtain a second differential output waveform,
A pulse wave measuring device configured to obtain a measurement value of a displacement of a distance of an object based on a phase difference between a first differential output waveform and a second differential output waveform. A pulse wave measuring device including at least one electromagnetic wave oscillating unit, at least one reflected synthetic wave receiving unit, a first multiplying unit, a second multiplying unit, and a displacement measuring unit,
The electromagnetic wave oscillation unit is configured to oscillate the first electromagnetic wave and the second electromagnetic wave and irradiate the object,
The reflected synthesized wave receiving unit is configured to receive the reflected synthesized wave and obtain a reflected synthesized wave waveform,
The first multiplication unit is configured to obtain a first differential output waveform by multiplying the reflected synthesized wave waveform and the first frequency waveform,
The second multiplier is located at a different location from the first multiplier, and is configured to obtain a second differential output waveform by multiplying the reflected composite wave and the second frequency waveform,
The pulse wave according to claim 1, wherein the displacement measuring unit is configured to obtain a measurement result of a displacement of the distance of the object based on a phase difference between the first differential output waveform and the second differential output waveform. measuring device.   Electromagnetic wave oscillation so that the reflected combined wave waveform input to the first multiplier includes a waveform corresponding to the second reflected wave, and the reflected combined wave waveform input to the second multiplier includes the waveform corresponding to the first reflected wave The pulse wave measuring device according to claim 2, wherein a range of irradiation of the first electromagnetic wave and the second electromagnetic wave by the unit is set. The electromagnetic wave oscillation unit includes a first electromagnetic wave oscillation unit for irradiating the first electromagnetic wave, and a second electromagnetic wave oscillation unit for irradiating the second electromagnetic wave,
Pulse wave measuring device
A first antenna that is a first electromagnetic wave oscillating unit and a reflected synthetic wave receiving unit;
A second electromagnetic wave oscillating unit, and a second antenna that is a reflected synthetic wave receiving unit,
The first antenna receives the reflected composite wave including the second reflected wave,
As the second antenna receives the reflected composite wave including the first reflected wave,
The pulse wave measuring device according to claim 2 or 3, wherein a positional relationship between the first antenna and the second antenna is set. A first electromagnetic wave irradiation region corresponding to a half-value angle on the surface of the object of the first electromagnetic wave;
The range of irradiation of the first electromagnetic wave and the second electromagnetic wave object by the electromagnetic wave oscillating unit is set so that there is a portion where the second electromagnetic wave irradiation region corresponding to the half-value angle on the object surface of the second electromagnetic wave overlaps. The pulse wave measuring device according to any one of claims 2 to 4.   The pulse wave measuring device according to any one of claims 2 to 5, wherein the first electromagnetic wave and the second electromagnetic wave are directly oscillated by an electromagnetic wave oscillating unit, obtained by a harmonic of the oscillated electromagnetic wave, or obtained by multiplication. The reflected composite wave waveform is input to the first multiplier and the second multiplier, which are two mixers arranged at a predetermined distance,
The pulse wave measuring device according to any one of claims 2 to 6, wherein the phase difference is a phase difference between output waveforms of the two mixers.   The pulse wave measuring device according to any one of claims 2 to 7, wherein the first frequency and the second frequency are frequencies of 7 GHz or more.   The pulse wave measuring device according to any one of claims 2 to 7, wherein the first frequency and the second frequency are frequencies between 10 GHz and 100 GHz.   The object is irradiated with the first electromagnetic wave and the second electromagnetic wave, the reflected synthetic wave reception unit is two antennas, and the two antennas are connected to the first multiplication unit and the first multiplication unit, respectively. The pulse wave measuring device according to any one of claims 2 to 9.   The displacement measuring unit includes an extra-pulse wave displacement removing unit that removes a displacement based on at least one of respiration, body motion, and movement of the pulse wave measurement device included in the displacement of the distance. The pulse wave measuring device according to any one of the above.   The pulse wave measuring device according to any one of claims 2 to 11, wherein the displacement measuring unit continuously obtains the result of measuring the displacement of the distance to the object.   The pulse wave measurement device according to any one of claims 2 to 12, further comprising an index calculation unit that obtains a calculation result of an index related to a pulse wave based on the displacement of the distance of the object measured by the displacement measurement unit.   An index related to pulse wave is calculated based on the maximum or minimum value of the displacement of distance with respect to time, the time between multiple maximum values or minimum values, or the difference in values between multiple maximum values or minimum values The pulse wave measuring device according to any one of claims 2 to 13, which is an index.   The pulse wave measuring device according to claim 13 or 14, wherein the index is an index related to arterial stiffness.   The pulse wave measuring device according to any one of claims 13 to 15, wherein the index is an estimated value of PWV or AI.   The determination result corresponding to the preset pattern is set, the displacement pattern of the distance measured by the displacement measuring unit is compared with the preset pattern, and based on the comparison result The pulse wave measuring device according to claim 2, further comprising a determination unit that obtains a determination result.   The result is at least normal, arteriosclerosis, hypertension / hyperlipidemia, obstructive hypertrophic cardiomyopathy, dilated cardiomyopathy, aortic regurgitation, hyperthyroidism, obstructive arteriosclerosis / diabetes The pulse wave measuring device according to claim 17, which is a result of the determination regarding any one of them.   The storage unit according to any one of claims 2 to 17, further comprising storage means for associating and storing the result together with the pulse wave information in which the displacement of the distance of the object measured by the displacement measuring unit is recorded at a predetermined sampling rate for a predetermined time. Pulse wave measuring device.   20. The system according to claim 2, further comprising a notification unit that notifies a result, wherein a notification mode in the case of a measurement abnormality in which a result is not obtained and a notification mode of a measurement result in a case where the result is obtained are different notification modes. The pulse wave measuring device according to claim 1.   A plurality of the pulse wave measuring devices according to any one of claims 2 to 20, wherein the object of each pulse wave measuring device is set at a position corresponding to a blood vessel of a different part of the same person, and the displacement of each pulse wave measuring device A pulse wave measurement device that calculates an index relating to a pulse wave based on a deviation of a measurement result of a distance displacement from an object output from a measurement unit. An object fixing means for fixing the object;
The pulse wave measuring device according to any one of claims 1 to 20, wherein the object fixing means is a bed or a chair.