JP2014008310A - Pulse wave sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pulse wave sensor capable of accurately measuring a subject's pulse wave.SOLUTION: A pulse wave sensor 1 includes: an optical sensor part 11 that applies light to an organism 2 from a light-emitting part to make a light-receiving part detect intensity of the light transmitted through the organism 2; a body part 10a for supporting the optical sensor part 11; a belt 20 that is attached to the body part 10a to be wound around the organism 2; and a buffer member 10c that is provided between the optical sensor part 11 and the body part 10a.

Description

  The present invention relates to a pulse wave sensor.

  A conventional pulse wave sensor is configured to measure a pulse wave using a light emitting unit that irradiates infrared light onto a fingertip of a subject and a light receiving unit that detects the intensity of infrared light transmitted through the living body. It had been.

  In addition, Patent Document 1 and Patent Document 2 can be cited as examples of related art related to the above.

  Conventionally, a technique for detecting a sleep state from the pulse of a subject has been proposed (see, for example, Patent Document 3).

Japanese Patent Laid-Open No. 5-212016 International Publication No. 2002/066222 Pamphlet JP 2003-79588 A

  However, the conventional pulse wave sensor basically measures the pulse wave when the subject is at rest, and it is difficult to accurately measure the pulse wave when the subject is exercising.

  Further, in the conventional structure in which the pulse wave is measured with the fingertip of the subject, it is necessary to restrict the behavior of the subject so that the pulse wave sensor does not drop from the fingertip during the measurement of the pulse wave. In addition, the pulse wave measurement at the fingertip has a problem that it is easily affected by noise caused by the movement of the subject.

  The conventional pulse wave sensor basically measures a pulse wave indoors, and it is difficult to accurately measure the pulse wave outdoors.

  Moreover, the conventional sleep sensor detects a subject's sleep state from single biological information (such as a pulse), and there is room for further improvement in the detection accuracy. Moreover, the conventional sleep sensor functions as a single unit, and it has not been possible to realize a physical condition management system or a home appliance control system using the sleep sensor.

  One of the various inventions disclosed in the present specification is to provide a pulse wave sensor capable of measuring a pulse wave of a subject with high accuracy.

  Another object of the present invention disclosed in the present specification is to provide a sleep sensor that is more practical and convenient.

  The pulse wave sensor disclosed in the present specification carries an optical sensor unit that irradiates light to a living body from a light emitting unit and detects the intensity of light transmitted through the living body by a light receiving unit, and the optical sensor unit. A configuration (first configuration) having a main body, a belt attached to the main body and wound around the living body, and a buffer member provided between the optical sensor unit and the main body; Has been.

  The pulse wave sensor having the first configuration further includes a printed wiring board on which the optical sensor unit is mounted, and the buffer member is provided between the printed wiring board and the main body. A configuration (second configuration) is preferable.

  The pulse wave sensor having the first or second configuration may be configured to further include a contact member (third configuration) that is provided around the optical sensor unit and is in close contact with the living body.

  Further, in the pulse wave sensor having the third configuration, the contact member may be configured to be provided with a gap (fourth configuration) between the optical sensor unit.

  The pulse wave sensor having any one of the second to fourth configurations may be configured to further include a protective member (fifth configuration) that covers at least one of the front surface and the back surface of the printed wiring board.

  In the pulse wave sensor having the fifth configuration, at least one of the contact member and the protection member may be configured to be black (sixth configuration).

  Further, in the pulse wave sensor having any one of the second to sixth configurations, the belt and the printed wiring board are attached to the main body with a gap that does not contact each other (seventh configuration) ).

  In the pulse wave sensor having any one of the first to seventh configurations, the main body portion may be configured to have a low center of gravity structure (eighth configuration).

  The pulse wave sensor having any one of the first to eighth configurations may further include a configuration (9th configuration) further including a filter unit that performs a filtering process on the output signal of the optical sensor unit.

  In the pulse wave sensor having the ninth configuration, the filter unit has a bandpass filter circuit (tenth configuration) that removes a low-frequency component and a high-frequency component from the output signal of the optical sensor unit. Good.

  Further, in the pulse wave sensor having the tenth configuration, the band pass filter circuit is a sixth-order operational amplifier multiple feedback type band filter circuit having a pass frequency band of 0.7 to 3.0 Hz (the eleventh configuration). (Configuration).

  Further, the pulse wave sensor disclosed in the present specification includes an optical sensor unit that irradiates a living body with light from a light emitting unit and detects the intensity of light transmitted through the living body with a light receiving unit, and the light emitting unit is provided as an external device. It has a configuration (a twelfth configuration) that includes a pulse driving unit that performs pulse driving with higher luminance than light, and a filter unit that performs detection processing on the output signal of the optical sensor unit to extract a pulse wave signal. .

  In the pulse wave sensor having the twelfth configuration, the wavelength characteristic of the light receiving unit may be configured to match the wavelength characteristic of the light emitting unit (a thirteenth configuration).

  In the pulse wave sensor having the twelfth or thirteenth configuration, the pulse driving unit may be configured to pulse drive the light emitting unit with a duty of 1/10 to 1/100 (14th configuration). .

  Further, in the pulse wave sensor having any one of the twelfth to fourteenth configurations, the filter unit detects a detection circuit that performs a detection process on the output signal of the optical sensor unit, and a first amplification that amplifies the output signal of the detection circuit. Circuit, a band pass filter circuit for removing low frequency components and high frequency components from the output signal of the first amplifier circuit, a low pass filter circuit for removing high frequency components from the output signal of the band pass filter circuit, and the low pass filter And a second amplifier circuit for amplifying the output signal of the circuit (a fifteenth configuration).

  Further, in the pulse wave sensor having the fifteenth configuration, the band pass filter circuit is a sixth-order operational amplifier multiple feedback type band filter circuit having a pass frequency band of 0.7 to 3.0 Hz (a sixteenth configuration). (Configuration).

  In the pulse wave sensor having the fifteenth or sixteenth configuration, the low-pass filter circuit may be a first-order CR low-pass filter circuit having a cutoff frequency of 1.45 Hz (seventeenth configuration). .

  In the pulse wave sensor having any one of the fifteenth to seventeenth configurations, the filter unit includes an intermediate voltage generation circuit that divides a power supply voltage to generate an intermediate voltage, and the detection circuit, the first The amplifier circuit, the band-pass filter circuit, the low-pass filter circuit, and the second amplifier circuit may all be configured to operate with the intermediate voltage as a reference voltage (eighteenth configuration).

  In the pulse wave sensor having any one of the first to eighteenth configurations, the output wavelength of the light emitting unit may be configured to belong to the visible light region of about 600 nm or less (19th configuration).

  According to the pulse wave sensor disclosed in this specification, the pulse wave of the subject can be accurately measured regardless of the subject's motion state (stationary / exercise) and the pulse wave measurement location (indoor / outdoor). Therefore, the usage scene of the pulse wave sensor can be expanded.

Schematic diagram for explaining the principle of pulse wave measurement at the wrist Waveform diagram showing how the attenuation (absorbance) of light in a living body changes over time Block diagram showing the first embodiment of the pulse wave sensor Sectional drawing which shows the 1st structural example of the optical sensor part 11 typically Sectional drawing which shows the 2nd structural example of the optical sensor part 11 typically Waveform diagram showing correlation between offset distance ΔH and signal intensity Waveform diagram showing correlation between inter-element distance W1 and signal intensity Sectional drawing which shows the 3rd structural example of the optical sensor part 11 typically Sectional drawing which shows the 4th structural example of the optical sensor part 11 typically Sectional drawing which shows the 5th structural example of the optical sensor part 11 typically Sectional drawing which shows the 6th structural example of the optical sensor part 11 typically Sectional drawing which shows the 7th structural example of the optical sensor part 11 typically Arrangement layout diagram of optical sensor section 11 in wristwatch type pulse wave sensor 1 Waveform diagram showing correlation between arrangement of optical sensor unit 11 and signal intensity Arrangement layout diagram of optical sensor unit 11 in earring type pulse wave sensor 1 Circuit diagram showing a first configuration example of the filter unit 12 Circuit diagram showing a second configuration example of the filter unit 12 Output waveform diagram of filter unit 12 Block diagram showing a second embodiment of the pulse wave sensor Sectional view schematically showing the generation mechanism of body movement noise Sectional drawing which shows typically one structural example of a pulse wave sensor Plan view schematically showing an example of the structure of a pulse wave sensor Circuit diagram showing a third configuration example of the filter unit 12 The graph which shows the measurement result at the time of walking (6km / h) Graph showing the measurement results during jogging (8 km / h) A graph showing the measurement results during jogging (10 km / h) The graph which shows the measurement result at the time of running (12km / h) The graph which shows the measurement result at the time of running (14km / h) The graph which shows the measurement result at the time of running (16km / h) Comparison table between the constant lighting method and the pulse lighting method Circuit diagram showing one configuration example of the pulse driving unit 17 Schematic diagram for explaining pulse wave signal detection processing (demodulation processing) The graph which shows the light emission characteristic and light reception characteristic of the optical sensor part 11 New and old comparison table of pulse wave measurement results Graph showing pulse wave measurement results indoors and outdoors Schematic diagram for explaining the principle of pulse wave measurement in the ear External view showing a third embodiment of the pulse wave sensor Block diagram showing a third embodiment of the pulse wave sensor Front view schematically showing an example of mounting the earphone 1X on the first form and the outer ear E Front view schematically showing a second form of the earphone 1X and an example of attachment to the outer ear E Front view schematically showing a third embodiment of the earphone 1X and an example of attachment to the outer ear E Front view schematically showing a fourth embodiment of the earphone 1X and an example of attachment to the outer ear E System diagram showing a variation of the pulse wave sensor (earplug structure) System diagram showing an application example to a hearing aid Block diagram showing a configuration example of a sleep sensor The schematic diagram which shows one structural example of the household appliance control system using the sleep sensor 501 Schematic diagram showing a first wearing example (forehead wearing type) of the sleep sensor 501 Schematic diagram showing a second wearing example (ear wearing type) of the sleep sensor 501

<Principle of pulse wave measurement>
FIG. 1 is a schematic diagram for explaining the principle of pulse wave measurement at the wrist, and FIG. 2 is a waveform diagram showing how the attenuation (absorbance) of light in the living body changes with time.

In the pulse wave measurement by the volume pulse wave method, for example, as shown in FIG. 1, a light emitting unit (LED [Light Emitting Diode] or the like) is directed toward a part of a living body (wrist in FIG. 1) pressed against a measurement window. ), And the intensity of the light transmitted through the body and coming out of the body is detected by a light receiving unit (a photodiode, a phototransistor, or the like). Here, as shown in FIG. 2, the attenuation (absorbance) of light due to living tissue and venous blood (deoxygenated hemoglobin Hb) is constant, but the attenuation of light due to arterial blood (oxygenated hemoglobin HbO ₂ ). (Absorbance) varies with time due to pulsation. Therefore, by utilizing the “biological window” (wavelength range where light is easily transmitted through the living body) from the visible region to the near-infrared region, the change in the absorbance of the peripheral artery is measured, so that the volume pulse wave can be generated non-invasively. Can be measured.

  In FIG. 1, for convenience of illustration, a state in which the pulse wave sensor (light emitting unit and light receiving unit) is mounted on the back side (outside) of the wrist is depicted, but the mounting position of the pulse wave sensor is limited to this. It may be on the ventral side (inside) of the wrist or other part (fingertip, third joint of the finger, forehead, between eyebrows, nose tip, cheek, under the eye, temple, earlobe, etc.) Also good.

<What you can understand from the pulse wave>
Note that the pulse wave under the control of the heart and the independent nerve does not always exhibit a constant behavior, but causes various changes (fluctuations) depending on the condition of the subject. Accordingly, various body information of the subject can be obtained by analyzing the change (fluctuation) of the pulse wave. For example, from the heart rate, it is possible to know the exercise ability, the degree of tension, and the like of the subject, and from the heart rate variability, it is possible to know the fatigue level, the degree of sleep, the magnitude of stress, and the like. Further, from the acceleration pulse wave obtained by differentiating the pulse wave twice with respect to the time axis, the blood vessel age, arteriosclerosis degree, etc. of the subject can be known.

<Pulse wave sensor (first embodiment)>
FIG. 3 is a block diagram showing the first embodiment of the pulse wave sensor. The pulse wave sensor 1 according to the first embodiment is a bracelet structure (watch) including a main unit 10 and a belt 20 that is attached to both ends of the main unit 10 and is wound around a living body 2 (specifically, a wrist). Type structure). As a material of the belt 20, leather, metal, resin, or the like can be used.

  The main unit 10 includes an optical sensor unit 11, a filter unit 12, a control unit 13, a display unit 14, a communication unit 15, and a power supply unit 16.

  The optical sensor unit 11 is provided on the back surface (surface on the side facing the living body 2) of the main unit 10, and irradiates the living body 2 with light from the light emitting unit, and determines the intensity of light transmitted through the living body. By detecting the pulse wave data, the pulse wave data is acquired. In the pulse wave sensor 1 of the first embodiment, the optical sensor unit 11 has a configuration in which the light emitting unit and the light receiving unit are provided on opposite sides of the living body 2 (so-called transmission type, see the broken line arrow in FIG. 1). In other words, both the light emitting unit and the light receiving unit are provided on the same side with respect to the living body 2 (so-called reflection type, see solid line arrow in FIG. 1). In addition, the inventors of the present application have actually confirmed through experiments that pulse waves can be sufficiently measured for wrist pulse waves. The specific structure of the optical sensor unit 11 will be described in detail later.

  The filter unit 12 performs filter processing and amplification processing on the output signal (detection signal of the light receiving unit) of the optical sensor unit 11 and transmits the result to the control unit 13. A specific circuit configuration of the filter unit 12 will be described later in detail.

  The control unit 13 controls the overall operation of the pulse wave sensor 1 as well as performing various signal processing on the output signal of the filter unit 12 to thereby provide various information on the pulse wave (pulse wave fluctuation, heart rate). , Heart rate variability, acceleration pulse wave, etc.). As the control unit 13, a CPU [central processing unit] or the like can be preferably used.

  The display unit 14 is provided on the surface of the main unit 10 (the surface on the side not facing the living body 2), and outputs display information (including information on date and time as well as pulse wave measurement results). . That is, the display unit 14 corresponds to a dial face of a wristwatch. In addition, as the display part 14, a liquid crystal display panel etc. can be used suitably.

  The communication unit 15 transmits the measurement data of the pulse wave sensor 1 to an external device (such as a personal computer or a mobile phone) wirelessly or by wire. In particular, if the measurement data of the pulse wave sensor 1 is wirelessly transmitted to an external device, it is not necessary to connect the pulse wave sensor 1 and the external device by wire, so that, for example, without restricting the behavior of the subject Measurement data can be transmitted in real time. In addition, when the pulse wave sensor 1 has a waterproof structure, it is desirable to adopt a wireless transmission method as an external transmission method of measurement data from the viewpoint of completely eliminating external terminals. Note that when the wireless transmission method is employed, a Bluetooth (registered trademark) wireless communication module IC or the like can be suitably used as the communication unit 15.

  The power supply unit 16 includes a battery and a DC / DC converter, converts an input voltage from the battery into a desired output voltage, and supplies it to each part of the pulse wave sensor 1. Thus, with the battery-driven pulse wave sensor 1, it is not necessary to connect an external power supply cable when measuring the pulse wave, and thus the pulse wave can be measured without restricting the behavior of the subject. It becomes possible. In addition, as said battery, it is desirable to use the secondary battery (A lithium ion secondary battery, an electric double layer capacitor, etc.) which can be charged repeatedly. Thus, if it is the structure using a secondary battery as a battery, since the troublesome battery replacement | work operation | work will become unnecessary, the convenience of the pulse wave sensor 1 can be improved. In addition, as a power supply method from the outside during battery charging, a contact power supply method using a USB [universal serial bus] cable or the like may be used, or an electromagnetic induction method, an electric field coupling method, and a magnetic field resonance method. For example, a non-contact power feeding method may be used. However, when the pulse wave sensor 1 has a waterproof structure, it is desirable to employ a non-contact power feeding method as an external power supply method from the viewpoint of completely eliminating external terminals.

  As described above, if the pulse wave sensor 1 has a bracelet structure, the pulse wave sensor 1 falls off the wrist during measurement of the pulse wave unless the subject intentionally removes the pulse wave sensor 1 from the wrist. Since there is almost no fear, the pulse wave can be measured without restricting the behavior of the subject.

  Further, if the pulse wave sensor 1 has a bracelet structure, it is not necessary to make the subject wear the pulse wave sensor 1 so much, so that it is continuous over a long period (several days to several months). Even when a simple pulse wave measurement is performed, it is not necessary to apply excessive stress to the subject.

  In particular, if the pulse wave sensor 1 is equipped with the display unit 14 (that is, the pulse wave sensor 1 having a wrist watch structure) that can display not only the measurement result of the pulse wave but also date and time information, the subject is the pulse wave sensor. Since 1 can be worn daily as a wristwatch, it is possible to further wipe away the resistance to wearing of the pulse wave sensor 1 and, in turn, contribute to the development of new user groups.

  The pulse wave sensor 1 is preferably a waterproof structure. With such a configuration, it is possible to measure a pulse wave without failure even when wet with water (rain) or sweat. Further, when the pulse wave sensor 1 is shared by a large number of people (for example, when used for lending in a gym), the pulse wave sensor 1 can be kept clean by washing the whole pulse wave sensor 1 with water. It becomes possible.

<Optical sensor part (structure)>
FIG. 4 is a cross-sectional view schematically showing a first configuration example of the optical sensor unit 11. The optical sensor unit 11 of the first configuration example includes a case 11a, a light shielding wall 11b, a translucent plate 11z, a light emitting unit x, and a light receiving unit y.

  The case 11a is a bowl-shaped member that houses the light emitting part x and the light receiving part y. The case 11a is embedded in the main unit 10 so that the transparent plate 11z that closes the opening surface is flush with the surface of the main unit 10 (the surface on the side facing the living body 2).

  The light shielding wall 11b is a member that divides the case 11a into a first area where the light emitting part x is placed and a second area where the light receiving part y is placed. By providing the light shielding wall 11b, it is possible to block light that is directly incident on the light receiving part y from the light emitting part x, so that it is possible to improve the detection accuracy of the pulse wave data. The case 11a and the light shielding wall 11b are preferably formed integrally.

  The translucent plate 11z is a translucent member that closes the opening surface of the case 11a. By providing the translucent plate 11z, the light emitting part x and the light receiving part y can be prevented from being contaminated (attachment of dust or the like). Therefore, the light emitting part x and the light receiving part y are not sealed with a resin or the like. (Light emitting chip and light receiving chip) can be used.

  In the case of the optical sensor unit 11 of the first configuration example, the light wave from the light emitting unit x to the living body 2 is detected, and then the light intensity of the light transmitted through the living body 2 is detected by the light receiving unit y. Is possible to get.

  However, in the optical sensor unit 11 of the first configuration example, since the translucent plate 11z exists between the living body 2, the light emitting unit x, and the light receiving unit y, light is emitted through the translucent plate 11z without passing through the living body 2. There is a possibility that light may be directly incident from the part x to the light receiving part y. Further, in the optical sensor unit 11 of the first configuration example, external light may leak into the light receiving unit y when the adhesion between the optical sensor unit 11 and the living body 2 is impaired. When light that does not pass through the living body 2 is incident on the light receiving unit y, the pulse wave data detection accuracy (S / N) is lowered. Therefore, in order to improve the pulse wave data detection accuracy, It is important to eliminate the problem.

  FIG. 5 is a cross-sectional view schematically showing a second configuration example of the optical sensor unit 11. The optical sensor unit 11 of the second configuration example includes a case 11a, a light shielding wall 11b, a light emitting unit X, and a light receiving unit Y. That is, in the optical sensor unit 11 of the second configuration example, the above-described translucent plate 11z is excluded.

  The case 11a is a bowl-shaped member that houses the light emitting unit X and the light receiving unit Y. The outer dimensions (height H0, width W0, depth D0) of the case 11a are designed to be, for example, H0 = 1.5 mm, W0 = 4.5 mm, and D0 = 3.0 mm. The case 11a is embedded in the main unit 10 so as to protrude from the main unit 10 by a predetermined dimension H4 (for example, H4 = 0.3 mm). With such a configuration, it is possible to block outside light leaking into the light receiving unit Y by the protruding portion of the case 11a, so that it is possible to improve the detection accuracy of the pulse wave data.

  The light shielding wall 11b is a member that divides the case 11a into a first area where the light emitting part X is placed and a second area where the light receiving part Y is placed. Similar to the first embodiment described above, by providing the light blocking wall 11b, it is possible to block the light that is directly incident on the light receiving unit Y from the light emitting unit X, so that it is possible to improve the detection accuracy of the pulse wave data. It becomes. The case 11a and the light shielding wall 11b are preferably formed integrally.

  The light emitting unit X includes a substrate X1, a light emitting chip X2, a sealing body X3, a wire X4, and a conductor X5. The substrate X1 is a member on which the light emitting chip X2 is placed. The light emitting chip X2 is a light emitting element (for example, a green LED bare chip) that outputs light of a predetermined wavelength. The sealing body X3 is a translucent member that seals the light emitting chip X2. The wire X4 is a member that electrically connects the light emitting chip X2 and the conductor X5. The conductor X5 is a conductive member formed from the upper surface to the lower surface of the substrate X1, and is soldered to the wiring pattern formed on the bottom surface of the case 11a.

  The light receiving unit Y includes a substrate Y1, a light receiving chip Y2, a sealing body Y3, a wire Y4, and a conductor Y5. The substrate Y1 is a member on which the light receiving chip Y2 is placed. The light receiving chip Y2 is a photoelectric conversion element (for example, a bare chip of a phototransistor having photosensitivity in the near infrared region to the visible region) that converts light belonging to a predetermined wavelength region into an electric signal. The sealing body Y3 is a translucent member that seals the light receiving chip Y2. The wire Y4 is a member that electrically connects the light receiving chip Y2 and the conductor Y5. The conductor Y5 is a conductive member formed from the upper surface to the lower surface of the substrate Y1, and is soldered to the wiring pattern formed on the bottom surface of the case 11a.

  As described above, in the optical sensor unit 11 of the second configuration example, a package type semiconductor device is used as the light emitting unit X and the light receiving unit Y instead of a bare chip. Therefore, since it is not necessary to cover the opening surface of the case 11a with a translucent plate, it is possible to eliminate the concern that light is directly incident on the light receiving unit Y from the light emitting unit X through the translucent plate. As a result, the detection accuracy of pulse wave data can be increased.

  Further, in the optical sensor unit 11 of the second configuration example, a relationship of H1> H2 is established between the height H1 of the light shielding wall 11b and the height H2 of the light emitting unit X. The height H1 of the light shielding wall 11b indicates the distance (for example, H1 = 1.4 mm) from the bottom surface of the case 11a to the upper end of the light shielding wall 11b. Further, the height H2 of the light emitting portion X indicates the distance (for example, H2 = 0.5 mm) from the bottom surface of the case 11a to the light emitting surface of the light emitting chip X2. However, considering that the light emitting chip X2 is very thin compared to the substrate X1, the thickness of the substrate X1 can be handled as the height H2 of the light emitting portion X.

  If the dimensional design satisfying the above relational expression is performed, the light directly incident on the light receiving part Y from the light emitting part X can be effectively blocked by the light shielding wall 11b, so that the detection accuracy of the pulse wave data is improved. It becomes possible.

  However, if the height H2 of the light emitting portion X is designed to be too small compared to the height H1 of the light shielding wall 11b, the light emitted from the light emitting portion X is scattered or attenuated before reaching the living body 2, The intensity of the light detected by the light receiving unit Y decreases, and the detection accuracy of the pulse wave data decreases. Therefore, an optimum design range exists for the offset distance ΔH (= H1−H2) obtained by subtracting the height H2 of the light emitting portion X from the height H1 of the light shielding wall 11b.

  FIG. 6 is a waveform diagram showing the correlation between the offset distance ΔH and the signal intensity (peak-to-peak value of the received light signal). In order from the top, ΔH = 0.6 mm, 0.7 mm, 0.9 mm, 1. The received light waveforms when 1 mm and 2.1 mm are depicted. FIG. 6 shows that the signal intensity becomes maximum when the offset distance ΔH is 0.9 mm. In view of this experimental result, it can be said that the offset distance ΔH is desirably within the design range of 0 mm <ΔH <2 mm (more preferably, 0.6 mm ≦ ΔH ≦ 1.4 mm).

  For example, when the light emitting part X including the sealing body X3 having a thickness of 0.6 mm is used and the offset distance ΔH is designed to be 0.9 mm, the upper surface of the sealing body X3 is 0 from the upper end of the light shielding wall 11b. The thickness of the substrate X1 may be designed so that the height position is recessed by 3 mm.

  Further, in the optical sensor unit 11 of the second configuration example, a relationship of H2> H3 is established between the height H2 of the light emitting unit X and the height H3 of the light receiving unit Y. The height H3 of the light receiving unit Y indicates the distance (for example, H3 = 0.3 mm) from the bottom surface of the case 11a to the light receiving surface of the light receiving chip Y2. However, in view of the fact that the light receiving chip Y2 is very thin compared to the substrate Y1, the thickness of the substrate Y1 can be handled as the height H3 of the light receiving portion Y.

  If the dimensional design satisfying the above relational expression is performed, it becomes difficult for external light to reach the light receiving unit Y, so that the detection accuracy of the pulse wave data can be improved.

  Next, how the signal intensity changes according to the inter-element distance W1 between the light emitting unit X and the light receiving unit Y will be considered with reference to FIG. FIG. 7 is a waveform diagram showing the correlation between the inter-element distance W1 and the signal intensity. From the top, W1 = 0.1 mm, 0.5 mm, 1.0 mm, 3.0 mm, and 5.0 mm. The received light waveform at a certain time is depicted. FIG. 7 shows that the signal intensity is maximized when the inter-element distance W1 is 0.5 mm. In view of this experimental result, it can be said that the inter-element distance W1 is preferably within the design range of 0.1 mm ≦ W1 ≦ 3.0 mm (more preferably 0.2 mm ≦ W2 ≦ 0.8 mm).

  Next, a modification of the optical sensor unit 11 will be described with reference to FIGS. 8A to 8D. 8A to 8D are cross-sectional views schematically showing third to sixth configuration examples of the optical sensor unit 11, respectively. The third configuration example to the sixth configuration example are substantially the same as the above-described second configuration example, and various components are added in order to further improve the detection accuracy of the pulse wave data.

  For example, the optical sensor unit 11 of the third configuration example (FIG. 8A) has a condenser lens 11 c on the light emitting unit X. By providing the condensing lens 11c, the light emitted from the light emitting part X can be collected and irradiated on the living body 2, so that the intensity of the light detected by the light receiving part Y is increased and the detection accuracy of the pulse wave data is increased. It becomes possible to improve.

  Further, in the optical sensor unit 11 of the fourth configuration example (FIG. 8B), the first region where the light emitting unit X is placed is covered with a lid member 11d having an opening d1 smaller than the light emitting region of the light emitting unit X. Has been. For example, when the light emitting area of the light emitting part X is a 0.7 mm square rectangular area, the opening d1 may be formed in a circular shape with a diameter of 0.5 mm or a rectangular shape with a 0.5 mm square. By providing the lid member 11d, it is possible to prevent the light emitted from the light emitting part X from diffusing and to block the light directly incident on the light receiving part Y from the light emitting part X. The accuracy can be increased.

  Further, in the optical sensor unit 11 of the fifth configuration example (FIG. 8C), the second region where the light receiving unit Y is placed is covered with a lid member 11e having an opening d2 larger than the light receiving region of the light receiving unit Y. Has been. For example, when the light emitting area of the light receiving portion Y is a rectangular area of 0.7 mm square, the opening d <b> 2 may be formed in a circular shape with a diameter of 1.0 mm or a rectangular shape of 1.0 mm square. By providing the lid member 11e, it is possible to block external light that leaks into the light receiving unit Y, and thus it is possible to improve the detection accuracy of pulse wave data.

  In the optical sensor unit 11 of the sixth configuration example (FIG. 8D), at least one of the light emitting unit X and the light receiving unit Y selectively allows only a predetermined wavelength component (near the output peak wavelength of the light emitting unit X) to pass therethrough. Color filters X6 and Y6 are included. By providing the color filters X6 and Y6, unnecessary wavelength components can be removed, so that the detection accuracy of pulse wave data can be increased.

  Next, a further modification of the optical sensor unit 11 will be described with reference to FIG. FIG. 9 is a cross-sectional view schematically showing a seventh configuration example of the optical sensor unit 11. The seventh configuration example is substantially the same configuration as the second configuration example described above, and is devised to further improve the detection accuracy of the pulse wave data.

  The optical sensor unit 11 of the seventh configuration example includes a buffer member 11f between the main unit 10 and the case 11a. As the buffer member 11f, rubber, synthetic sponge, or the like can be suitably used. By setting it as such a structure, since the adhesiveness of the optical sensor part 11 and the biological body 2 can be improved, it becomes possible to measure a pulse wave stably.

  It should be noted that the components added in the third configuration example (FIG. 8A) to the sixth configuration example (FIG. 8D) and the seventh configuration example (FIG. 9) may be applied independently. It may be applied in any combination.

<Optical sensor section (arrangement)>
FIG. 10 is an arrangement layout diagram of the optical sensor unit 11 in the wristwatch type pulse wave sensor 1. In the wristwatch-type pulse wave sensor 1, the body unit 10 (for example, 28 mm in diameter) that carries the optical sensor unit 11 is connected to the belt 20 at both ends, and when worn on the living body 2 (wrist), the belt 20 This is a member to which a pressing force (see a thick arrow in FIG. 10) to the living body 2 side is given by tightening 20.

  Regarding the pulse wave sensor 1 having such a wrist watch structure, the inventors of the present application have a predetermined distribution of the pressing force applied to the main body unit 10 toward the living body 2, and the position where the optical sensor unit 11 is disposed. According to the above, it was found that the adhesion between the optical sensor unit 11 and the living body 2 (and hence the signal intensity of the received light signal) is different.

  The inventors of the present application have studied the optical sensor unit from the vicinity of the applied point where the pressing force to the living body 2 side becomes maximum, more specifically, from the connection point between the main unit 10 and the belt 20 after intensive research. When the distance to the arrangement position 11 (the center position of the optical sensor unit 11) is D, the optical sensor unit 11 is arranged in an area where the relationship of D ≦ 10 mm is established (in the hatched area in FIG. 10). It has been found that the signal intensity of the received light signal can be improved.

  FIG. 11 is a waveform diagram showing the correlation between the arrangement of the optical sensor unit 11 and the signal intensity. In the upper stage, the optical sensor unit 11 arranged at the end of the main unit 10 (within the hatched area in FIG. 10). In the lower part, the received light waveform of the optical sensor unit 11 ′ arranged in the central part of the main unit 10 (outside the hatched area in FIG. 10) is shown. As can be seen by comparing the two waveforms, the optical sensor unit 11 disposed at the end of the main unit 10 has improved adhesion to the living body 2, and as a result, the subject's movements as well as the pulse wave when the subject is at rest. It is possible to measure the pulse wave at the time with high accuracy.

  Note that the knowledge obtained above can be applied not only to the wristwatch-type pulse wave sensor 1 but also to the earring-type pulse wave sensor 1 as shown in FIG.

  FIG. 12 is an arrangement layout diagram of the optical sensor unit 11 in the earring-type pulse wave sensor 1. In the earring-type pulse wave sensor 1, the main body unit 10 (for example, the total length from the first end to the second end is 24 mm) that carries the optical sensor unit 11 is connected to the spring hinge 30 at the first end and the second end. Is a member to which a pressing force (refer to a thick arrow in FIG. 12) to the living body 2 side is given by the spring hinge 30 when attached to the living body 2 (earlobe).

  In this case, the application point at which the pressing force toward the living body 2 is maximized is the second end (open end) of the main unit 10. Therefore, when the distance from the second end (open end) of the main unit 10 to the position where the optical sensor unit 11 is disposed (the center position of the optical sensor unit 11) is D, a region where the relationship of D ≦ 10 mm is established. If the optical sensor part 11 is arrange | positioned in the inside, the adhesiveness of the optical sensor part 11 and the biological body 2 can be improved, and the signal strength of a received light signal can be improved.

  10 and 12 exemplify a configuration in which only one optical sensor unit 11 is provided on the surface of the main unit 10, the number of the optical sensor units 11 is not limited to this. Alternatively, a plurality of optical sensor units 11 may be provided in the vicinity of the applied point where the pressing force toward the living body 2 is maximized.

<Filter section>
FIG. 13 is a circuit diagram illustrating a first configuration example of the filter unit 12. The filter unit 12 of the first configuration example includes a current / voltage conversion circuit 100, a first-order CR high-pass filter circuit 110 (hereinafter referred to as an HPF [high pass filter] circuit 110), an amplifier circuit 120, and a first-order CR low-pass. A filter circuit 130 (hereinafter referred to as an LPF [low pass filter] circuit 130) and an amplifier circuit 140 are included.

  The current / voltage conversion circuit 100 is a circuit that converts a current signal output from the optical sensor unit 11 into a voltage signal, and includes a resistor R1 (for example, 200 kΩ). The anode of the light emitting diode 11A forming the optical sensor unit 11 is connected to the application terminal of the power supply voltage VDD. The cathode of the light emitting diode 11A is connected to the ground terminal. The collector of the phototransistor 11B forming the photosensor unit 11 is connected to the application terminal of the power supply voltage VDD via the resistor R1. The emitter of the phototransistor 11B is connected to the ground terminal.

  The HPF circuit 110 is a circuit that removes a low-frequency component superimposed on the output signal of the current / voltage conversion circuit 100, and includes a capacitor C1 (for example, 0.1 μF) and a resistor R2 (for example, 4.7 MΩ). The first end of the capacitor C1 is connected to the collector of the phototransistor 11B. The second terminal of the capacitor C1 is connected to the ground terminal via the resistor R2. Note that the cut-off frequency of the HPF circuit 110 configured as described above is designed to be 0.34 Hz.

  The amplifier circuit 120 is a circuit that amplifies the output signal of the HPF circuit 110, and includes an operational amplifier OP1, a resistor R3 (for example, 100 kΩ), a resistor R4 (for example, 10 kΩ), a capacitor C2 (for example, 0.01 μF), and a capacitor C3. (For example, 0.1 μF). The non-inverting input terminal (+) of the operational amplifier OP1 is connected to the second terminal of the capacitor C1. The inverting input terminal (−) of the operational amplifier OP1 is connected to the output terminal of the operational amplifier OP1 through the resistor R3, and is also connected to the ground terminal through the resistor R4. The first power supply terminal of the operational amplifier OP1 is connected to the application terminal of the power supply voltage VDD. The second power supply terminal of the operational amplifier OP1 is connected to the ground terminal. The capacitor C2 is connected in parallel with the resistor R3. The capacitor C3 is connected between the first power supply terminal of the operational amplifier OP1 and the ground terminal.

  The LPF circuit 130 is a circuit that removes a high-frequency component superimposed on the output signal of the amplifier circuit 120, and includes a resistor R5 (for example, 100 kΩ) and a capacitor C4 (for example, 1.0 μF). The first end of the resistor R5 is connected to the output end of the operational amplifier OP1. A second terminal of the resistor R5 is connected to the ground terminal via the capacitor C4. Note that the cut-off frequency of the LPF circuit 130 configured as described above is set to 1.6 Hz.

  The amplifier circuit 140 is a circuit that amplifies the output signal of the LPF circuit 130, and includes an operational amplifier OP2, a variable resistor R6 (for example, 500 kΩ), a resistor R7 (for example, 10 kΩ), a capacitor C5 (for example, 0.01 μF), and a capacitor. C6 (for example, 0.1 μF). The non-inverting input terminal (+) of the operational amplifier OP2 is connected to the second terminal of the resistor R5. The inverting input terminal (−) of the operational amplifier OP2 is connected to the output terminal of the operational amplifier OP2 through the variable resistor R6, and is also connected to the ground terminal through the resistor R7. The first power supply terminal of the operational amplifier OP2 is connected to the application terminal of the power supply voltage VDD. The second power supply terminal of the operational amplifier OP2 is connected to the ground terminal. The capacitor C5 is connected in parallel with the variable resistor R6. The capacitor C6 is connected between the first power supply terminal and the ground terminal of the operational amplifier OP2.

  With the filter unit 12 of the first configuration example, the noise component superimposed on the output signal of the optical sensor unit 11 can be removed with a simple circuit configuration, and the detection accuracy of the pulse wave data can be increased.

  However, in the filter unit 12 of the first configuration example, the subject's body movement noise (noise component of about 6.0 Hz generated by exercise) may not be sufficiently removed, and the pulse wave during exercise of the subject is highly accurate. Therefore, there was room for further improvement (see the lower part of FIG. 15).

  FIG. 14 is a circuit diagram illustrating a second configuration example of the filter unit 12. The filter unit 12 of the second configuration example includes a current / voltage conversion circuit 200, a primary CR high-pass filter circuit 210 (hereinafter referred to as an HPF circuit 210), a voltage follower circuit 220, and a secondary CR low-pass filter circuit 230 ( (Hereinafter referred to as LPF circuit 230), amplifier circuit 240, sixth-order band pass filter circuit 250 (hereinafter referred to as BPF [band pass filter] circuit 250), amplifier circuit 260, intermediate voltage generation circuit 270, Have

  The current / voltage conversion circuit 200 is a circuit that converts a current signal output from the optical sensor unit 11 into a voltage signal, and includes a resistor R8 (for example, 200 kΩ) and a resistor R9 (for example, 430Ω). The anode of the light emitting diode 11A forming the optical sensor unit 11 is connected to the application terminal of the power supply voltage VDD. The cathode of the light emitting diode 11A is connected to the ground terminal via the resistor R9. The collector of the phototransistor 11B that forms the optical sensor unit 11 is connected to the application terminal of the power supply voltage VDD via the resistor R8. The emitter of the phototransistor 11B is connected to the ground terminal.

  The HPF circuit 210 is a circuit that removes a low-frequency component superimposed on the output signal of the current / voltage conversion circuit 200, and includes a capacitor C7 (for example, 1.0 μF) and a resistor R10 (for example, 240 kΩ). The first end of the capacitor C7 is connected to the collector of the phototransistor 11B. The second end of the capacitor C7 is connected to the application end of the intermediate voltage VM via the resistor R10. The cutoff frequency of the HPF circuit 210 having the above configuration is designed to be 0.66 Hz.

  The voltage follower circuit 220 is a circuit that transmits the output signal of the HPF circuit 110 to the subsequent stage, and includes an operational amplifier OP3 and a capacitor C8 (for example, 0.1 μF). The non-inverting input terminal (+) of the operational amplifier OP3 is connected to the second terminal of the capacitor C7. The inverting input terminal (−) of the operational amplifier OP3 is connected to the output terminal of the operational amplifier OP3. The first power supply terminal of the operational amplifier OP3 is connected to the application terminal of the power supply voltage VDD. The second power supply terminal of the operational amplifier OP3 is connected to the ground terminal. The capacitor C8 is connected between the first power supply terminal and the ground terminal of the operational amplifier OP3.

  The LPF circuit 230 is a circuit that removes a high frequency component superimposed on the output signal of the voltage follower circuit 220, and includes a resistor R11 (eg, 620 kΩ), a resistor R12 (eg, 620 kΩ), a capacitor C9 (eg, 1.0 μF), Capacitor C10 (for example, 1.0 μF). The first end of the resistor R11 is connected to the output end of the operational amplifier OP3. The second end of the resistor R11 is connected to the first end of the resistor R12, and is connected to the application end of the intermediate voltage VM via the capacitor C9. The second end of the resistor R12 is connected to the application end of the intermediate voltage VM via the capacitor C10. Note that the cut-off frequency of the LPF circuit 230 configured as described above is set to 0.26 Hz.

  The amplifier circuit 240 is a circuit that amplifies the output signal of the LPF circuit 230, and includes an operational amplifier OP4, a resistor R13 (for example, 10 kΩ), a resistor R14 (for example, 1 kΩ), and a capacitor C11 (for example, 0.1 μF). . The non-inverting input terminal (+) of the operational amplifier OP4 is connected to the second terminal of the resistor R12. The inverting input terminal (−) of the operational amplifier OP4 is connected to the output terminal of the operational amplifier OP4 through the resistor R13, and is also connected to the application terminal of the intermediate voltage VM through the resistor R14. The first power supply terminal of the operational amplifier OP4 is connected to the application terminal of the power supply voltage VDD. The second power supply terminal of the operational amplifier OP4 is connected to the ground terminal. The capacitor C11 is connected between the first power supply terminal of the operational amplifier OP4 and the ground terminal.

  The BPF circuit 250 is a circuit for removing both the low frequency component and the high frequency component superimposed on the output signal of the amplifier circuit 240, and includes operational amplifiers OP5 to OP7, a resistor R15 (for example, 75 kΩ), and a resistor R16 (for example, 2 MΩ). A resistor R17 (for example, 150 kΩ), a resistor R18 (for example, 130 kΩ), a resistor R19 (for example, 91 kΩ), a resistor R20 (for example, 620 kΩ), a resistor R21 (for example, 43 kΩ), a resistor R22 (for example, 30 kΩ), A resistor R23 (for example, 200 kΩ), a capacitor C12 (for example, 1 μF), a capacitor C13 (for example, 1 μF), a capacitor C14 (for example, 0.1 μF), a capacitor C15 (for example, 1 μF), a capacitor C16 (for example, 1 μF), Capacitor C17 (for example, 0.1 μF) and capacitor C18 (for example, It includes a 1 .mu.F), a capacitor C19 (e.g. 1 .mu.F), capacitor C20 (e.g. 0.1ĩF), the.

  The first end of the resistor R15 is connected to the output end of the operational amplifier OP4. The 2nd end of resistance R15 is connected to the application end of intermediate voltage VM via resistance R16. The non-inverting input terminal (+) of the operational amplifier OP5 is connected to the application terminal for the intermediate voltage VM. The inverting input terminal (−) of the operational amplifier OP5 is connected to the second terminal of the resistor R15 through the capacitor C12, and is also connected to the output terminal of the operational amplifier OP5 through the resistor R17. The first power supply terminal of the operational amplifier OP5 is connected to the application terminal of the power supply voltage VDD. The second power supply terminal of the operational amplifier OP5 is connected to the ground terminal. The capacitor C13 is connected between the second end of the resistor R15 and the output end of the operational amplifier OP5. The capacitor C14 is connected between the first power supply terminal and the ground terminal of the operational amplifier OP5.

  The first end of the resistor R18 is connected to the output end of the operational amplifier OP5. The 2nd end of resistance R18 is connected to the application end of intermediate voltage VM via resistance R19. The non-inverting input terminal (+) of the operational amplifier OP6 is connected to the application terminal for the intermediate voltage VM. The inverting input terminal (−) of the operational amplifier OP6 is connected to the second terminal of the resistor R18 via the capacitor C15, and is also connected to the output terminal of the operational amplifier OP6 via the resistor R20. The first power supply terminal of the operational amplifier OP6 is connected to the application terminal of the power supply voltage VDD. The second power supply terminal of the operational amplifier OP6 is connected to the ground terminal. The capacitor C16 is connected between the second end of the resistor R18 and the output end of the operational amplifier OP6. The capacitor C17 is connected between the first power supply terminal of the operational amplifier OP6 and the ground terminal.

  The first end of the resistor R21 is connected to the output end of the operational amplifier OP6. The 2nd end of resistance R21 is connected to the application end of intermediate voltage VM via resistance R22. The non-inverting input terminal (+) of the operational amplifier OP7 is connected to the application terminal for the intermediate voltage VM. The inverting input terminal (−) of the operational amplifier OP7 is connected to the second terminal of the resistor R21 via the capacitor C18, and is also connected to the output terminal of the operational amplifier OP7 via the resistor R23. The first power supply terminal of the operational amplifier OP7 is connected to the application terminal of the power supply voltage VDD. The second power supply terminal of the operational amplifier OP7 is connected to the ground terminal. The capacitor C19 is connected between the second end of the resistor R21 and the output end of the operational amplifier OP7. The capacitor C20 is connected between the first power supply terminal and the ground terminal of the operational amplifier OP7.

  The BPF circuit 250 having the above configuration has a pass frequency band of 0.80 to 2.95 Hz.

  The amplifier circuit 260 is a circuit that amplifies the output signal of the BPF circuit 250, and includes an operational amplifier OP8, a variable resistor R24 (for example, 1 MΩ), a resistor R25 (for example, 1 kΩ), and a capacitor C21 (for example, 0.1 μF). Including. The non-inverting input terminal (+) of the operational amplifier OP8 is connected to the output terminal of the operational amplifier OP7. The inverting input terminal (−) of the operational amplifier OP8 is connected to the output terminal of the operational amplifier OP8 through the variable resistor R24, and is also connected to the application terminal of the intermediate voltage VM through the resistor R25. The first power supply terminal of the operational amplifier OP8 is connected to the application terminal of the power supply voltage VDD. The second power supply terminal of the operational amplifier OP8 is connected to the ground terminal. The capacitor C21 is connected between the first power supply terminal and the ground terminal of the operational amplifier OP8.

  The intermediate voltage generation circuit 260 is a circuit that divides the power supply voltage VDD by half to generate an intermediate voltage VM (= VDD / 2), and includes a resistor R26 (for example, 1 kΩ), a resistor R27 (for example, 1 kΩ), Capacitor C22 (0.1 μF). A first end of the resistor R26 is connected to an application end of the power supply voltage VDD. The second end of the resistor R26 and the first end of the resistor R27 are both connected to the application end of the intermediate voltage VM. A second end of the resistor R27 is connected to the ground end. The capacitor C22 is connected in parallel with the resistor R27.

  With the filter unit 12 of the second configuration example, the body motion noise of the subject can be appropriately removed, so that not only the pulse wave when the subject is at rest but also the pulse wave when the subject is exercising (for example, walking) Can be detected with high accuracy (see the upper part of FIG. 15).

  In the filter unit 12 of the second configuration example, the HPF circuit 210, the LPF filter circuit 230, the amplifier circuit 240, the BPF circuit 250, and the amplifier circuit 260 all use the intermediate voltage VM (= VDD / 2) as the reference voltage. Therefore, the output signal of the filter unit 12 has a waveform whose amplitude varies vertically with respect to the intermediate voltage VM. Therefore, with the filter unit 12 of the second configuration example, saturation of the output signal (sticking to the power supply voltage VDD or the ground voltage) can be prevented and pulse wave data can be detected correctly.

<Pulse wave sensor (second embodiment)>
FIG. 16 is a block diagram showing a second embodiment of the pulse wave sensor. The pulse wave sensor 1 of the second embodiment basically has the same configuration as that of the first embodiment, but adopts a body motion noise suppression structure in order to perform pulse wave measurement during exercise or outdoors with higher accuracy. In addition, the driving method of the optical sensor unit 11 is changed. When changing the driving method of the optical sensor unit 11, the main unit 10 includes a pulse driving unit 17 that drives the light emitting unit of the optical sensor unit 11 with a higher luminance than external light. The filter unit 12 includes a detection circuit that performs detection processing (demodulation processing) on the output signal of the optical sensor unit 11. Note that specific configurations of the pulse driving unit 17 and the filter unit 12 will be described in detail later.

<Measurement technology development during exercise>
As described above, the bracelet type pulse wave sensor 1 measures the pulse wave not only when the subject is stationary but also when the subject is performing a relatively light exercise (such as walking). Can be done correctly. However, when the subject is performing relatively intense exercise (jogging, running, etc.), the pulse wave may not be measured correctly due to the influence of body motion noise, leaving room for further improvement. It was.

  The body motion noise will be considered with reference to FIG. FIG. 17 is a cross-sectional view schematically showing a mechanism for generating body movement noise. In the pulse wave sensor 1 (hereinafter, sometimes referred to as an old-type pulse wave sensor 1 for convenience of explanation) that does not employ the body motion noise suppression structure described later, a minute body change accompanying the movement of the subject (the surface of the skin) When the vibration is transmitted to the main body 10a of the pulse wave sensor 1 through the belt 20 wound around the living body (wrist) 2 due to tension, wrinkle / muscle movement, etc., the vibration is almost attenuated. Without being transmitted to the printed wiring board 10b attached to the main body 10a. As a result, the optical distance between the optical sensor unit 11 mounted on the printed wiring board 10b and the living body (wrist) 2 changes greatly due to the vibration described above, and this is the body movement noise. Appears in the output signal.

  FIG. 18 and FIG. 19 are cross-sectional views schematically showing a configuration example of a pulse wave sensor 1 (hereinafter, sometimes referred to as a new type of pulse wave sensor 1 for convenience of explanation) that employs a body motion noise suppression structure. And a plan view (a plan view of the pulse wave sensor 1 viewed from the lower surface side where the optical sensor unit 11 is mounted).

  In the new pulse wave sensor 1, the main body unit 10 includes a main body portion 10a, a printed wiring board 10b, a buffer member 10c, an adhesive member 10d, and a protective member 10e.

  The main body 10a is a housing that carries the components (such as the optical sensor 11) of the pulse wave sensor 1. The belt 20 is attached to both ends of the main body 10 a and is wound around the living body (wrist) 2. The main body 10a may have a low center-of-gravity structure by avoiding a multilayer structure or by disposing a relatively heavy member (battery or the like) on the side close to the living body (wrist) 2. If such a low center-of-gravity structure is adopted, the main body 10a is less likely to vibrate even during the movement of the subject, so the change in the optical distance between the optical sensor 11 and the living body (wrist) 2 is reduced, and body motion noise Occurrence can be reduced.

  The printed wiring board 10b is a member on which electronic circuit components such as the optical sensor unit 11 are mounted, and is attached to the lower surface (the surface facing the living body (wrist) 2) of the main body unit 10a. The printed wiring board 10b is designed to be slightly smaller in size than the main body 10a in plan view, and the belt 20 and the printed wiring board 10b have a gap (about 5 mm) that does not contact each other. It is attached to the main body 10a. By adopting such a structure, vibration hardly propagates directly from the belt 20 to the printed wiring board 10b even when the subject exercises, so that the optical distance change between the optical sensor unit 11 and the living body (wrist) 2 is small. Thus, the occurrence of body movement noise can be reduced.

  The buffer member 10c is a member having high vibration absorption (flexibility or elasticity) provided between the printed wiring board 10b and the main body 10a (and thus between the optical sensor 11 and the main body 10a). is there. As the buffer member 10c, a gel material such as a shock absorbing gel, sponge, rubber or the like can be used. By providing the buffer member 10c, vibration propagation from the main body 10a to the optical sensor unit 11 can be reduced, so that the optical distance change between the optical sensor unit 11 and the living body (wrist) 2 is reduced, and body motion noise is reduced. Occurrence can be reduced.

  The adhesive member 10 d is a highly adhesive member that is provided around the optical sensor unit 11 and is in close contact with the living body (wrist) 2. As the adhesive member 10d, a double-sided tape or an adhesive pad can be used. The thickness of the adhesive member 10 d is designed to be the same as that of the optical sensor unit 11 or lower than that of the optical sensor unit 11. By providing the adhesive member 10d, the adhesion between the optical sensor unit 11 and the living body (wrist) 2 can be improved, so that the optical distance change between the optical sensor unit 11 and the living body (wrist) 2 is reduced, and the body Generation of dynamic noise can be reduced. The adhesive member 10d is preferably provided with a gap (about 5 mm) between the optical sensor unit 11 and the adhesive member 10d. By adopting such a structure, the optical sensor unit 11 can easily receive the light returning from the living body (wrist) 2, so that the measurement accuracy of the pulse wave can be increased. Further, the adhesive member 10 d also functions as a light shielding member for preventing external light from leaking into the optical sensor unit 11. When paying attention to the light shielding function, it is desirable that the adhesive member 10d be black that easily absorbs external light.

  The protection member 10e is a member for covering at least one of the front and back surfaces of the printed wiring board 10b to protect electronic circuit components (such as the optical sensor unit 11) from impact and contamination. As the protective member 10e, an insulating tape, a resin coating, or the like can be used. The protective member 10e is desirably black as is the adhesive member 10d.

  FIG. 20 is a circuit diagram illustrating a third configuration example of the filter unit 12. The filter unit 12 of the third configuration example includes a current / voltage conversion circuit 300, a detection circuit 310, an amplification circuit 320, and a sixth-order operational amplifier multiple feedback type bandpass filter 330 (hereinafter referred to as a BPF [band pass filter] circuit 330). A first-order low-pass filter circuit 340 (hereinafter referred to as an LPF circuit [low pass filter] 340), an amplifier circuit 350, and an intermediate voltage generation circuit 360.

  The current / voltage conversion circuit 300 is a circuit that converts a current signal output from the optical sensor unit 11 into a voltage signal, and includes a resistor R28 (for example, 430Ω) and a resistor R29 (for example, 200 kΩ). The anode of the light emitting diode 11A (corresponding to the light emitting part) forming the optical sensor part 11 is connected to the application terminal of the power supply voltage VDD (for example, + 3.3V) via the pulse driving part 17. The cathode of the light emitting diode 11A is connected to the application terminal of the ground voltage GND2 via the resistor R28. The collector of the phototransistor 11B (corresponding to the light receiving unit) forming the photosensor unit 11 is connected to the application terminal of the power supply voltage VDD via the resistor R29. The emitter of the phototransistor 11B is connected to the application terminal of the ground voltage GND.

  The detection circuit (demodulation circuit) 310 performs detection processing (demodulation processing) on the output signal of the current / voltage conversion circuit 300, and includes an operational amplifier OP9, a resistor R30 (for example, 10 kΩ), and a resistor R31 (for example, 160 kΩ). A resistor R32 (for example, 16 kΩ), a resistor R33 (for example, 10 kΩ), a resistor R34 (for example, 10 kΩ), a resistor R35 (for example, 620 kΩ), a capacitor C23 (for example, 1.0 μF), and a capacitor C24 (for example, 10 nF). And a capacitor C25 (for example, 0.1 μF), a capacitor C26 (for example, 1.0 μF), a capacitor C27 (for example, 1.0 μF), and diodes D1 and D2. The collector of the phototransistor 11B is connected to the application terminal of the intermediate voltage VM through the resistor R30. The first end of the capacitor C23 is connected to the collector of the phototransistor 11B. A second terminal of the capacitor C23 is connected to an application terminal for the intermediate voltage VM via a resistor R31. A first end of the resistor R32 is connected to a second end of the capacitor C23. A second terminal of the resistor R32 is connected to an application terminal for the intermediate voltage VM via the capacitor C24. The inverting input terminal (−) of the operational amplifier OP9 is connected to the second terminal of the resistor R32 via the resistor R33. The non-inverting input terminal (+) of the operational amplifier OP9 is connected to the application terminal for the intermediate voltage VM. The first power supply terminal of the operational amplifier OP9 is connected to the application terminal for the power supply voltage VDD. The second power supply terminal of the operational amplifier OP9 is connected to the application terminal for the ground voltage GND. The anode of the diode D1 and the first end of the resistor R34 are both connected to the inverting input terminal (−) of the operational amplifier OP9. Both the cathode of the diode D1 and the anode of the diode D2 are connected to the output terminal of the operational amplifier OP9. A second end of the resistor R34 is connected to the cathode of the diode D2. The capacitor C25 is connected between the first power supply terminal of the operational amplifier OP9 and the application terminal of the ground voltage GND. The capacitor C26 is connected between the cathode of the diode D2 and the application end of the intermediate voltage VM. A first end of the resistor R35 is connected to the cathode of the diode D2. The second end of the resistor R35 is connected to the application end of the intermediate voltage VM via the capacitor C27. The operation of the detection circuit 310 will be described in detail later together with the operation of the pulse driving unit 17.

  The amplifier circuit 320 is a circuit that amplifies the output signal of the detection circuit 310, and includes an operational amplifier OP10, a resistor R36 (for example, 100 kΩ), a resistor R37 (for example, 10 kΩ), and a capacitor C28 (for example, 0.1 μF). . The non-inverting input terminal (+) of the operational amplifier OP10 is connected to the second terminal of the resistor R35. The inverting input terminal (−) of the operational amplifier OP10 is connected to the output terminal of the operational amplifier OP10 through the resistor R36, and is also connected to the application terminal of the intermediate voltage VM through the resistor R37. The first power supply terminal of the operational amplifier OP10 is connected to the application terminal of the power supply voltage VDD. The second power supply terminal of the operational amplifier OP10 is connected to the application terminal for the ground voltage GND. The capacitor C28 is connected between the first power supply terminal of the operational amplifier OP10 and the application terminal of the ground voltage GND.

  The BPF circuit 330 is a circuit for removing both low frequency components and high frequency components from the output signal of the amplifier circuit 320, and includes operational amplifiers OP11 to OP13, a resistor R38 (for example, 75 kΩ), and a resistor R39 (for example, 2 MΩ). , Resistor R40 (eg 150 kΩ), resistor R41 (eg 130 kΩ), resistor R42 (eg 91 kΩ), resistor R43 (eg 620 kΩ), resistor R44 (eg 43 kΩ), resistor R45 (eg 30 kΩ), resistor R46 (for example, 200 kΩ), capacitor C29 (for example, 1.0 μF), capacitor C30 (for example, 1.0 μF), capacitor C31 (for example, 0.1 μF), capacitor C32 (for example, 1.0 μF), and capacitor C33 (for example) For example, 1.0 μF), capacitor C34 (for example, 0.1 μF), and capacitor Sita containing C35 (e.g. 1.0μF), a capacitor C36 (eg 1.0μF), a capacitor C37 and a (e.g. 0.1ĩF).

  The first end of the resistor R38 is connected to the output end of the operational amplifier OP10. The second end of the resistor R38 is connected to the application end of the intermediate voltage VM via the resistor R39. The non-inverting input terminal (+) of the operational amplifier OP11 is connected to the application terminal for the intermediate voltage VM. The inverting input terminal (−) of the operational amplifier OP11 is connected to the second terminal of the resistor R38 via the capacitor C29, and is also connected to the output terminal of the operational amplifier OP11 via the resistor R40. The first power supply terminal of the operational amplifier OP11 is connected to the application terminal of the power supply voltage VDD. The second power supply terminal of the operational amplifier OP11 is connected to the application terminal of the ground voltage GND. The capacitor C30 is connected between the second end of the resistor R38 and the output end of the operational amplifier OP11. The capacitor C31 is connected between the first power supply terminal of the operational amplifier OP11 and the application terminal of the ground voltage GND.

  The first end of the resistor R41 is connected to the output end of the operational amplifier OP11. The second end of the resistor R41 is connected to the application end of the intermediate voltage VM via the resistor R42. The non-inverting input terminal (+) of the operational amplifier OP12 is connected to the application terminal for the intermediate voltage VM. The inverting input terminal (−) of the operational amplifier OP12 is connected to the second terminal of the resistor R41 via the capacitor C32, and is also connected to the output terminal of the operational amplifier OP12 via the resistor R43. The first power supply terminal of the operational amplifier OP12 is connected to the application terminal for the power supply voltage VDD. The second power supply terminal of the operational amplifier OP12 is connected to the application terminal of the ground voltage GND. The capacitor C33 is connected between the second end of the resistor R41 and the output end of the operational amplifier OP12. The capacitor C34 is connected between the first power supply terminal of the operational amplifier OP12 and the application terminal of the ground voltage GND.

  The first end of the resistor R44 is connected to the output end of the operational amplifier OP12. The 2nd end of resistance R44 is connected to the application end of intermediate voltage VM via resistance R45. The non-inverting input terminal (+) of the operational amplifier OP13 is connected to the application terminal for the intermediate voltage VM. The inverting input terminal (−) of the operational amplifier OP13 is connected to the second terminal of the resistor R44 through the capacitor C35, and is also connected to the output terminal of the operational amplifier OP13 through the resistor R46. The first power supply terminal of the operational amplifier OP13 is connected to the application terminal of the power supply voltage VDD. The second power supply terminal of the operational amplifier OP13 is connected to the application terminal of the ground voltage GND. The capacitor C36 is connected between the second end of the resistor R44 and the output end of the operational amplifier OP13. The capacitor C37 is connected between the first power supply terminal of the operational amplifier OP13 and the application terminal of the ground voltage GND.

  The operational amplifier multiple feedback type BPF circuit 330 having the above configuration has a pass frequency band of 0.7 to 3.0 Hz.

  The LPF circuit 340 is a circuit that removes a high frequency component from the output signal of the BPF circuit 330, and includes a resistor R47 (eg, 110 kΩ) and a capacitor C38 (eg, 1.0 μF). The first end of the resistor R47 is connected to the output end of the operational amplifier OP13. The second end of the resistor R47 is connected to the application end of the intermediate voltage VM via the capacitor C38. The cut-off frequency of the LPF circuit 340 having the above configuration is set to 1.45 Hz.

  The amplifier circuit 350 is a circuit that amplifies the output signal of the LPF circuit 340, and includes an operational amplifier OP14, a variable resistor R48 (for example, 1 MΩ), a resistor R49 (for example, 1 kΩ), and a capacitor C39 (for example, 0.1 μF). Including. The non-inverting input terminal (+) of the operational amplifier OP14 is connected to the second terminal of the resistor R47. The inverting input terminal (−) of the operational amplifier OP14 is connected to the output terminal of the operational amplifier OP14 through the variable resistor R48, and is also connected to the application terminal of the intermediate voltage VM through the resistor R49. The first power supply terminal of the operational amplifier OP14 is connected to the application terminal of the power supply voltage VDD. The second power supply terminal of the operational amplifier OP14 is connected to the application terminal for the ground voltage GND. The capacitor C39 is connected between the first power supply terminal of the operational amplifier OP14 and the application terminal of the ground voltage GND.

  The intermediate voltage generation circuit 360 is a circuit that divides the power supply voltage VDD by half to generate an intermediate voltage VM (= VDD / 2), and includes a resistor R50 (for example, 1 kΩ), a resistor R51 (for example, 1 kΩ), Capacitor C40 (1.0 μF). A first end of the resistor R50 is connected to an application end of the power supply voltage VDD. The second end of the resistor R50 and the first end of the resistor R51 are both connected to the application end of the intermediate voltage VM. The second end of the resistor R51 is connected to the end of the ground voltage GND. The capacitor C40 is connected in parallel with the resistor R51.

  With the filter unit 12 of the third configuration example, body motion noise can be effectively removed from the output signal (pulse wave data) of the optical sensor unit 11.

  In the filter unit 12 of the third configuration example, the detection circuit 310, the amplification circuit 320, the BPF circuit 330, the LPF circuit 340, and the amplification circuit 350 all use the intermediate voltage VM (= VDD / 2) as a reference voltage. Since it operates, the output signal of the filter unit 12 has a waveform whose amplitude varies up and down with respect to the intermediate voltage VM. Therefore, with the filter unit 12 of the third configuration example, saturation of the output signal (sticking to the power supply voltage VDD and the ground voltage GND) can be prevented and pulse wave data can be detected correctly.

  With the new type of pulse wave sensor 1 that employs a combination of the body motion noise suppression structure (FIGS. 18 and 19) and the filter unit 12 (FIG. 20), not only the pulse wave when the subject is at rest, but also the motion of the subject. It is possible to detect a pulse wave at the time (walking / jogging / running) with high accuracy.

  FIGS. 21 to 26 show the measurement results at walking (6 km / h), jogging (8 km / h, 10 km / h), and running (12 km / h, 14 km / h, 16 km / h), respectively. Upper: old model, lower: new model). The solid line in the figure shows the measurement result of the pulse wave sensor 1 (new / old), and the broken line in the figure shows the measurement result of the chest belt-mounted heart rate monitor (commercially available product) for comparison reference. . The above exercises (walking / jogging / running) are all performed using an indoor treadmill.

  When the old pulse wave sensor 1 was used, a measurement result correlated with the chest belt type heart rate monitor was obtained when the subject walked (upper part of FIG. 21), but body motion noise was observed when the subject was jogging or running. As a result, the measurement results deviated from the chest belt-mounted heart rate monitor (the upper sections of FIGS. 22 to 26).

  On the other hand, when the new pulse wave sensor 1 was used, it was confirmed that a measurement result correlated with the chest belt type heart rate monitor can be obtained not only when the subject walks but also when the subject jogs or runs. (Lower stages of FIGS. 21 to 26).

<Development of outdoor measurement technology>
The above-described new pulse wave sensor 1 has a higher luminance than the external light in the light emitting part (light emitting diode 11A) of the optical sensor part 11 so that the pulse wave can be correctly measured even outdoors (under sunlight that becomes disturbance light). The filter unit 12 includes a detection circuit 230 that performs a detection process on the output signal of the optical sensor unit 11 and extracts a pulse wave signal (see above). (See FIG. 20).

  The significance of changing the light emitting method of the optical sensor unit 11 from the constant lighting method to the pulse lighting method (duty driving method) will be described in detail with reference to FIG. FIG. 27 is a comparison table between the constant lighting method and the pulse lighting method. In order from the top, the brightness of the light emitting unit, the signal intensity S (pulse wave signal), the noise intensity N (disturbance light), and the S / N It is shown.

  The signal intensity S per unit time in the constant lighting method can be expressed as S = L (= L × 1) when the brightness of the light emitting unit is L (for example, 1.5 mA drive). On the other hand, the noise intensity N is expressed as N = (α × L) when the brightness of the ambient light is (α × L). Therefore, when α> 1, the noise intensity N is larger than the signal intensity S (S <N), and S / N cannot be secured.

  On the other hand, the signal intensity S per light emission time in the pulse lighting method (for example, drive frequency: 100 Hz, duty: 1/50) is S when the brightness of the light emitting unit is (50 × L) (for example, 75 mA drive). = L (= (50 × L) × (1/50)). On the other hand, the noise intensity N is expressed as N = (α × L) / 50 when the brightness of the disturbance light is (α × L). In this way, by combining the pulse lighting method and increasing the brightness of the light emitting part, the noise intensity N can be reduced according to the duty of the light emitting part while maintaining the signal intensity S at the same level as before. As a result, the S / N can be improved. The duty may be set to 1/10 to 1/100. For example, as described above, it is desirable to set the duty to 1/50. When the duty is set to 1/10, the brightness of the light emitting unit may be (10 × L), and when the duty is set to 1/100, the brightness of the light emitting unit is set to ( 100 × L).

  FIG. 28 is a circuit diagram illustrating a configuration example of the pulse driving unit 17. The pulse drive unit 17 of this configuration example includes a semiconductor device IC1, a P-channel MOS (metal oxide semiconductor) field effect transistor P1, resistors R52 to R55, and capacitors C41 to C43.

  The semiconductor device IC1 has three Schmitt triggers ST1 to ST3 and eight external terminals (1 to 8 pins). Pin 1 is connected to the input end of Schmitt trigger ST1. The second pin is connected to the output terminal of the Schmitt trigger ST2. The 3rd pin is connected to the input terminal of the Schmitt trigger ST3. Pin 4 is a ground terminal and is connected to the application terminal of the ground voltage GND2 outside the semiconductor device IC1. Pin 5 is connected to the output terminal of Schmitt trigger ST3. The 6th pin is connected to the input terminal of the Schmitt trigger ST2. Pin 7 is connected to the output terminal of Schmitt trigger ST1. Pin 8 is a power supply terminal and is connected to the application terminal of the power supply voltage VDD outside the semiconductor device IC1.

  The source of the transistor P1 is connected to the application terminal of the power supply voltage VDD. The drain of the transistor is connected to the anode of the light emitting diode 11A. The gate of the transistor P1 is connected to the application terminal of the power supply voltage VDD via the resistor R52, and is also connected to the 5th pin of the semiconductor device IC1 via the resistor R53. A first end of the resistor R54 is connected to pin 3 of the semiconductor device IC1. The second end of the resistor R54 is connected to the application end of the ground voltage GND2. The 1st end of resistance R55 is connected to 1 pin of semiconductor device IC1. The second end of the resistor R55 is connected to the 6th and 7th pins of the semiconductor device IC1. The capacitor C41 is connected between the application terminal of the power supply voltage VDD and the application terminal of the ground voltage GND2. The capacitor C42 is connected between the first pin of the semiconductor device IC1 and the application terminal of the ground voltage GND2. The capacitor C43 is connected between pins 2 and 3 of the semiconductor device IC1.

  The pulse driving unit 17 having the above configuration repeats on / off of the transistor P1 at a predetermined driving frequency and duty, and performs pulse driving of the current flowing through the light emitting diode 11A of the optical sensor unit 11. In addition, as the light emitting diode 11A, a high-luminance compatible element (peak forward current: 100 mA) is used.

  FIG. 29 is a schematic diagram for explaining a demodulation process (detection process) of a pulse wave signal in the detection circuit 310. 28, the input signal to the detection circuit 310 is depicted in the upper part of FIG. 28, and the output signal of the detection circuit 310 is depicted in the lower part of FIG. As shown in FIG. 20, the detection circuit 310 incorporated in the filter unit 12 is a so-called inverting half-wave rectification detection circuit, and an output signal obtained by extracting only the envelope from a pulse-driven input signal. Is generated and output to the subsequent circuit.

  FIG. 30 is a graph showing light emission characteristics and light reception characteristics of the optical sensor unit 11. The horizontal axis in FIG. 30 indicates the wavelength, and the vertical axis indicates the relative sensitivity. The solid line in the figure indicates the wavelength characteristic (light reception characteristic) of the new phototransistor, and the small broken line in the figure indicates the wavelength characteristic (light reception characteristic) of the old phototransistor. The large broken line in the figure indicates the wavelength characteristic (light emission characteristic) of the light emitting diode. As shown in FIG. 30, in the new pulse wave sensor 1, the wavelength characteristic (light receiving characteristic) of the new phototransistor used as the light receiving part matches the wavelength characteristic (light emitting characteristic) of the light emitting diode used as the light emitting part. Designed to be Thus, by optimizing the wavelength characteristics of the light emitting unit and the light receiving unit, it is possible to cut the sensitivity of unnecessary bands, so that the influence of external light (sunlight) can be reduced.

  The new pulse wave sensor 1 adopting a combination of the above-described pulse lighting method (FIGS. 20, 27 to 29) and wavelength characteristic optimization (FIG. 30) can be used not only indoors but also outdoors with a lot of disturbance light. Waves can be detected with high accuracy.

  FIG. 31 is an old and new comparison table of pulse wave measurement results in a stationary state (standing position) outdoors. The upper part of FIG. 31 shows the result of pulse wave measurement outdoors (40,000 lux) using the old pulse wave sensor 1, and the lower part of FIG. (Lux) pulse wave measurement results are shown. As shown in FIG. 31, in the old pulse wave sensor 1, the pulse wave signal is saturated due to the influence of extraneous light (sunlight), and the pulse wave cannot be measured correctly. The pulse wave sensor 1 can correctly measure the pulse wave by avoiding saturation of the pulse wave signal.

  FIG. 32 is a graph showing pulse wave measurement results indoors and outdoors by the new pulse wave sensor 1. The solid line in the figure indicates the measurement result of the new pulse wave sensor 1, and the broken line in the figure indicates the measurement result of the chest belt-mounted heart rate monitor (commercially available product) for comparison. As shown in FIG. 31, by using the new pulse wave sensor 1, not only indoors but also outdoors (80,000 lux), the chest can be used both at rest (sitting / standing) and walking. It was confirmed that measurement results correlated with the belt-mounted heart rate monitor can be obtained.

  Note that the outdoor measurement technique (pulse lighting method and wavelength characteristic optimization) described above is not limited to the bracelet type pulse wave sensor 1, but pulses of other structures (ring type, eye mask type, earplug type, etc.) It can be widely applied to wave sensors.

<Pulse wave measurement by ear>
FIG. 33 is a schematic diagram for explaining the principle of pulse wave measurement at the ear. In the first and second embodiments, the configuration in which the pulse wave measurement is mainly performed with the wrist has been described as an example. However, the pulse wave sensor can be attached to a part other than the wrist. Therefore, in the following third embodiment, an explanation will be given by taking as an example a configuration in which pulse waves are measured with the ear. In addition, when performing pulse wave measurement with the ear, the mounting position of the pulse wave sensor (light emitting unit and light receiving unit) can be any part of the outer ear E (boat fossa E1, ear ring E2, ear ring E3, anti tragus E4, It may be an external auditory canal E5, an upper earring leg E6, a triangular fossa E7, a lower earring leg E8, a concha E9, a tragus E10, an intercostal notch E11, and an earlobe E12).

<Pulse wave sensor (third embodiment)>
34 and 35 are an external view and a block diagram showing a third embodiment of the pulse wave sensor, respectively. The pulse wave sensor 401 of the third embodiment includes an earphone (headphone) 401X and a main unit 401Y, and is provided as a portable audio player having a pulse wave measurement function. The concept of the audio player includes not only a dedicated audio playback device but also a mobile phone terminal, a smartphone, a mobile game terminal, and the like having an audio playback function.

  The earphone 401X is an inner ear type that is used by being attached to the user's outer ear E (particularly the auricle (ear shell)), and includes a housing 410, an optical sensor unit 411, a speaker 412, a driver 413, and a cord 414. And a connector 415.

  The housing 410 is a member on which the optical sensor unit 411, the speaker 412, and the driver 413 are mounted. The housing 410 has a shape that fits into a hollow portion (boat portion of the concha E9) surrounded by the tragus E10 and the antitragus E4. The housing 410 may be an open type or a sealed type.

  The optical sensor unit 411 is provided on the side surface of the housing 410, and the light receiving unit 411B detects the intensity of light that irradiates a predetermined part of the outer ear E from the light emitting unit 411A and returns through the living body. By doing so, pulse wave data is acquired. Note that FIG. 34 shows a configuration in which one optical sensor unit 411 is mounted on one of the right ear housing and the left ear housing 410, but the number of optical sensor units 411 mounted is shown. However, the present invention is not limited to this, and a plurality of optical sensor units 411 may be mounted on one casing 410, or one or a plurality of optical sensor sections 411 may be mounted on both casings. Good. With a configuration in which only one optical sensor unit 411 is mounted, priority can be given to reduction of power consumption, cost reduction, and the like compared to a configuration in which a plurality of optical sensor units 411 are mounted. On the other hand, in the case of a configuration in which a plurality of optical sensor units 411 are mounted, pulse waves can be detected by adding each sensor output to increase S / N or selecting and using the sensor output having the highest S / N. The accuracy can be improved. In the case where a plurality of optical sensor units 411 are selectively used, waste of electric power can be prevented by cutting off power supply to the optical sensor units 411 that are not used.

  In the pulse wave sensor 401 of the third embodiment, the optical sensor unit 411 has a configuration in which a light emitting unit 411A and a light receiving unit 411B are provided on opposite sides of a living body (so-called transmission type, broken line arrow in FIG. 33). The light emitting unit 411A and the light receiving unit 411B are both provided on the same side with respect to the living body (so-called reflection type, see solid line arrows in FIG. 33). In addition, the inventors of the present application have actually confirmed through experiments that pulse waves can be sufficiently measured in the external ear E. About the specific structure of the optical sensor part 411, since the same structure as the optical sensor part 11 of 1st, 2nd embodiment should just be employ | adopted, the overlapping description is omitted.

  The speaker 412 converts an audio signal (electric signal) transmitted from the main unit 401Y via the driver 413 into a sound wave and outputs the sound wave. As a driving method of the speaker 412, a dynamic type is generally used, but other driving methods (magnetic type, balanced armature type, piezoelectric type, crystal type, electrostatic type, etc.) may be adopted.

  The driver 413 generates a driving signal for the speaker 412 based on the audio signal (electric signal) transmitted from the main unit 401Y.

  The code 414 is a member for electrically connecting the housing 410 of the earphone 401X and the main unit 401Y. The code 414 includes a signal transmission line and a power supply line.

  The connector 415 is attached to one end of the cord 414, and is a member for attaching / detaching the earphone 401X and the main unit 401Y.

  Instead of the cord 414 and the connector 415, a wireless communication module is provided in both the housing 410 and the main unit 401Y of the earphone 401X, so that the two can be connected wirelessly. In particular, when the main unit 401Y has a waterproof structure, it is desirable that the two are wirelessly connected from the viewpoint of completely eliminating the external terminals of the main unit 401Y. In that case, since power cannot be supplied from the main unit 401Y to the housing 410 side of the earphone 401X, it is necessary to separately prepare a power supply unit on the housing 410 side of the earphone 401X.

  The main unit 401Y includes a housing 420, a control unit 421, an operation unit 422, a display unit 423, a storage unit 424, a communication unit 425, a power supply unit 426, and a filter unit 427. When the main unit 401Y is a mobile phone terminal having an audio playback function, a microphone, a speaker, a telephone line connection unit, and the like are further added in addition to the above components.

  The housing 420 is a member that houses the control unit 421, the operation unit 422, the display unit 423, the storage unit 424, the communication unit 425, the power supply unit 426, and the filter unit 427. Note that the housing 420 is preferably provided with a waterproof structure in order to prevent failure due to submergence or the like.

  The control unit 421 not only individually realizes both the audio playback function and the pulse wave measurement function, but also generates a new added value by combining both functions in a complex manner. Overall control of the overall operation. Note that a CPU or the like can be preferably used as the control unit 421. The specific operation of the control unit 421 will be described later in detail.

  The operation unit 422 is a human interface that receives input operations (power on / off, volume adjustment, music selection, and the like) of a user (subject). As the operation unit 422, in addition to various keys and buttons, a touch panel or the like can be preferably used.

  The display unit 423 is provided on the surface of the main unit 401Y, and outputs display information (including information related to audio reproduction, including pulse wave measurement results). As the display portion 423, a liquid crystal display panel or the like can be preferably used.

  The storage unit 424 includes a ROM [read only memory] that stores various programs read and executed by the control unit 421 in a nonvolatile manner, and a volatile RAM [random access memory] used as a program execution area of the control unit 421. And a built-in (or detachable) flash memory for allowing a user (subject) to store arbitrary music data in a nonvolatile manner.

  The storage unit 424 stores a pulse wave data (raw data or processed data subjected to various processes) obtained by the control unit 421 in a volatile or non-volatile manner such as a RAM or an EEPROM [electrically erasable programmable. ROM]. In this way, with the configuration having the pulse wave data storage means, for example, the accumulated data in the storage unit 424 can be collectively transmitted at predetermined intervals, so the communication unit 425 is intermittently transmitted. Therefore, it is possible to extend the battery driving time of the pulse wave sensor 401.

  The communication unit 425 uses the measurement data (raw data, processed data subjected to various processes, or stored data in the storage unit 424) of the pulse wave sensor 401 as an external information terminal 402 (such as a data server or a personal computer). Send to or wirelessly. In particular, if the measurement data of the pulse wave sensor 401 is wirelessly transmitted to the information terminal 402, it is not necessary to connect the pulse wave sensor 401 and the information terminal 402 with a wire. Measurement data can be transmitted in real time without restricting the above. In particular, when the main unit 401Y has a waterproof structure, it is desirable to adopt a wireless transmission method as an external transmission method of measurement data from the viewpoint of completely eliminating the external terminals of the main unit 401Y. Note that when the measurement data is wirelessly transmitted to the information terminal 2 at a short distance (several meters to several tens of meters), a Bluetooth (registered trademark) wireless communication module or the like can be preferably used as the communication unit 425. In addition, when measuring data is transmitted to the remote information terminal 402 via the Internet or the like, a wireless LAN [local area network] module or the like can be preferably used as the communication unit 425.

  The power supply unit 426 includes a battery and a DC / DC converter, converts an input voltage from the battery into a desired output voltage, and supplies the output voltage to each unit of the pulse wave sensor 401. Thus, with the battery-driven pulse wave sensor 401, it is not necessary to connect an external power supply cable when measuring the pulse wave. Therefore, the pulse wave measurement can be performed without restricting the action of the user (subject). Can be done. In addition, as said battery, it is desirable to use the secondary battery (A lithium ion secondary battery, an electric double layer capacitor, etc.) which can be charged repeatedly. In this way, if the secondary battery is used as the battery, troublesome battery replacement work is not necessary, and the convenience of the pulse wave sensor 401 can be improved. Further, as a power supply method from the outside during battery charging, a contact power supply method using a USB cable or the like may be used, or a non-contact power supply such as an electromagnetic induction method, an electric field coupling method, and a magnetic field resonance method. It may be a method. However, when the pulse wave sensor 401 has a waterproof structure, it is desirable to employ a non-contact power feeding method as an external power supply method from the viewpoint of completely eliminating the external terminal of the main unit 401Y.

  The filter unit 427 performs filtering processing and amplification processing on the output signal (detection signal of the light receiving unit) of the optical sensor unit 411 and transmits the filtered signal to the control unit 421. Although a filter unit may be provided on the housing 410 side of the earphone 401X, it is considered that noise is likely to be superimposed in the middle of transmitting a signal from the housing 410 of the earphone 401X to the main unit 401Y via the cord 414. The filter unit 427 is desirably provided on the main unit 401Y side. In addition, about the specific circuit structure of the filter part 427, since the same structure as the filter part 12 of 1st, 2nd embodiment should just be employ | adopted, the overlapping description is omitted.

  As described above, the pulse wave sensor 401 according to the third embodiment includes the housing 410 attached to the outer ear E and the light emitted from the light emitting unit 411 </ b> A to the outer ear E so as to pass through the living body. And an optical sensor unit 411 that acquires pulse wave data by detecting the intensity of the returning light by the light receiving unit 411B.

  In such a configuration, unless the user (subject) intentionally removes the pulse wave sensor 401 from the outer ear E, there is little possibility that the pulse wave sensor 401 will drop out of the outer ear E during measurement of the pulse wave. The pulse wave can be measured without restricting the behavior of the user (subject).

  In particular, since the outer ear E is a part with less body movement compared to fingers and arms, the output signal of the optical sensor unit 411 is not easily influenced by body movement noise, and the pulse wave can be measured with high accuracy. It becomes.

  In addition, if the pulse wave sensor 401 includes the optical sensor unit 411 in the earphone 401X attached to the external ear E for the purpose of listening to sound, the user (subject) can use the pulse wave sensor 401 with a pulse wave measurement function. Since it can be worn on a daily basis as a portable audio player, it becomes possible to wipe out the sense of resistance to wearing the pulse wave sensor 401 and, in turn, contribute to the expansion of usage scenes and the development of new user groups. Is possible.

  In addition, the control unit 421 that comprehensively controls the operation of the entire pulse wave sensor 401 not only individually realizes both the audio playback function and the pulse wave measurement function, but also combines the functions in combination to create a new one. In order to produce added value, a function of controlling the output operation of the speaker 412 according to the pulse wave data is provided.

  More specifically, the control unit 421 performs various types of signal processing on the output signal of the filter unit 427, thereby various information regarding pulse waves (pulse wave fluctuation, heart rate, heart rate fluctuation, and acceleration pulse wave). Etc.) and the analysis result is fed back to the audio playback operation.

  For example, the control unit 421 determines the physical condition, mental state, sleep state, and the like of the user (subject) based on the analysis result of the pulse wave data, and adjusts the volume, selects music, or turns on the power based on the determination result. Automatically turn off / off. With such a configuration, it is possible to realize an audio playback operation that cannot be realized with a portable audio player alone.

  34 and 35 exemplify a configuration in which the earphone 401X and the main unit 401Y are separated from each other, the configuration of the pulse wave sensor 401 is not limited to this, and the earphone 401X and the main unit 401Y are not limited thereto. You may make it the structure which integrated. In that case, the cord 414 and the plug 415 are unnecessary.

  In addition, various variations of the form of the earphone 401X and the example of mounting to the outer ear E are conceivable as shown in FIGS. 36A to 36D. 36A to 36D are front views schematically showing the first to fourth forms of the earphone 401X and examples of mounting the earphone 401 to the outer ear E, respectively.

  For example, the earphone 401X of the first form (FIG. 36A) is an inner ear type that is used by being attached to the outer ear E, as in the previous FIG. 34, and the case 410 includes the tragus E10 and the antitragus E4. It has a shape (for example, a spherical shape or a cylindrical shape) that fits into a hollow portion surrounded by (a boat part of the concha E9). In the earphone 401 </ b> X of the first form, the optical sensor unit 411 is brought into contact with the hollow portion.

  The earphone 401X of the second form (FIG. 36B) is an earplug type (canal type) that is used by deeply pushing an earpiece made of silicon or foamed urethane into the external auditory canal E5. Similarly to the first form (FIG. 36A), it has a shape that fits into a hollow portion (boat portion of the concha E9) surrounded by the tragus E10 and the antitragus E4. In the earphone 401X of the second form, as in the first form, the optical sensor unit 411 is brought into contact with the hollow part.

  The earphone 401X of the third embodiment (FIG. 36C) is a headphone type including a housing 410 shaped to cover the entire auricle E. The right and left (right ear / left ear) housing 410 has a head sandwiched between a headband over the head or a neckband over the back of the neck (both not shown). In the earphone 401 </ b> X of the third form, the housing 410 has a protruding member 410 x that carries the optical sensor unit 411 on the surface (inner side surface) facing the pinna E. The protruding member 410x protrudes toward the pinna E, and, for example, the optical sensor unit 411 is mounted on the tip thereof. Therefore, in the earphone 401X of the third form, the optical sensor unit 411 is brought into contact with a portion (for example, the earlobe E12) facing the tip of the protruding member 410x. In the earphone 401X of the third form, the housing 410 that covers the entire auricle E also functions as a light shielding member that covers the optical sensor unit 411. With such a configuration, it is possible to stably measure pulse waves without being affected by external light.

  The earphone 401X of the fourth embodiment (FIG. 36D) is an ear hook type having a clip member 410y suspended on the pinna E. The clip member 410y carries the optical sensor unit 411 at a location where it abuts on the auricle E. Therefore, in the earphone 401X of the fourth form, the optical sensor unit 411 is brought into contact with the upper side of the upper ear ring leg E6, the triangular fossa E7, the lower opposite ear ring leg E8, or the back side of the concha E9.

  In the above description, the configuration in which the optical sensor unit 411 is provided in the earphone or the headphone is described as an example. However, the configuration of the pulse wave sensor 401 is not limited to this, and for example, a modification of FIG. As shown in FIG. 8, a configuration in which the optical sensor unit 411 is mounted on the housing 410 having the earplug structure and the pulse wave is measured inside the ear canal E5 is also conceivable. In this case, the housing 410 is inserted deeply by closing the ear canal E5, and the optical sensor unit 411 is in contact with the inner wall surface of the ear canal E5. With the pulse wave sensor 401 having such an earplug structure, the subject can be relaxed using the original function of the earplug, so that it is not necessary to apply excessive stress to the subject during the pulse wave measurement. From such a feature, the pulse wave sensor 401 having an earplug structure can be suitably used as a sleep sensor (a sensor that obtains knowledge about a sleep state of a subject from pulse wave information).

  In any case, the light receiving unit 411B may be disposed on the side closer to the ear canal E5 than the light emitting unit 411A (or the back side of the ear canal E5). By adopting such a configuration, it becomes difficult for external light to leak into the light receiving unit 411B, so that the detection accuracy of pulse wave data can be increased.

<Application to hearing aids>
FIG. 38 is a system diagram showing an application example to a hearing aid. The pulse wave sensor 401 of FIG. 38 is provided as a hearing aid having a pulse wave measurement function. The specific configuration of the pulse wave sensor 401 is basically the same as that shown in FIG. 35, but the components (such as a sound collection microphone) for functioning as a hearing aid instead of a portable audio player are appropriately used. Must be included.

  In addition, it is assumed that the information terminal 402 as a transmission destination of the pulse wave data and the analysis result (safety information, etc.) is installed in a remote place. Therefore, when applying to a hearing aid, the pulse wave sensor 401 is connected to the information terminal 402 (such as a data server of a medical institution or a personal computer owned by a remote family member) via the network 403. It is desirable to provide a communication unit (such as a wireless LAN module).

  Among users (subjects) who need hearing aids, there are many elderly people who need health management and safety confirmation from a remote location. However, it is not always easy for elderly people to install or maintain a plurality of electronic devices (here, hearing aids and pulse wave sensors) individually and appropriately.

  On the other hand, the pulse wave sensor 401 provided as a hearing aid having a pulse wave measurement function is a hearing aid itself for the user (subject) and does not make the user aware of the measurement of the pulse wave. It becomes possible to reduce the burden. In addition, by monitoring the pulse wave data transmitted from the pulse wave sensor 401 and the analysis result thereof at the remote information terminal 402, even if an abnormality occurs in the health condition of the user (subject), it can be promptly performed. It becomes possible to cope.

  As a matter of course, the configuration for measuring the pulse wave with the external ear E can be applied to a single pulse wave sensor that does not have additional functions such as an audio reproduction function and a hearing aid function.

<Sleep sensor>
FIG. 39 is a block diagram illustrating a configuration example (application example as a physical condition management system) of a sleep sensor. The sleep sensor 501 of this configuration example includes an optical sensor unit 511, a temperature sensor unit 512, an acceleration sensor unit 513, a microphone 514, a control unit 515, a display unit 516, a speaker 517, an operation unit 518, A storage unit 519, a communication unit 520, and a power supply unit 521 are included.

  The optical sensor unit 511 obtains measurement data relating to the pulse wave and blood oxygen saturation of the subject by detecting the intensity of light that passes through the living body and returns after irradiating the subject's living body with light. . In addition, about the optical sensor part 511, since what is necessary is just to employ | adopt the structure similar to previous 1st-3rd embodiment, the overlapping description is omitted.

  The temperature sensor unit 512 acquires measurement data related to the body temperature and body surface temperature of the subject.

  The acceleration sensor unit 513 acquires measurement data related to the body movement of the subject.

  The microphone 514 acquires measurement data relating to sounds and voices emitted by the subject and ambient sounds of the subject.

  The control unit 515 comprehensively controls the operation of the sleep sensor 501 as a whole. Note that a CPU or the like can be preferably used as the control unit 515.

  Display unit 516 outputs an image (including characters and the like) according to the sleep state of the subject. As the display portion 516, a liquid crystal display panel or the like can be preferably used.

  The speaker 517 outputs sound (including a warning sound) according to the sleep state of the subject.

  The operation unit 518 is a human interface that receives an input operation (such as power on / off) of the subject. As the operation unit 518, in addition to various keys and buttons, a touch panel or the like can be preferably used.

  The storage unit 519 includes a ROM that stores various programs read and executed by the control unit 515 in a nonvolatile manner, and a volatile RAM used as a program execution area of the control unit 515.

  The storage unit 519 also includes a RAM, an EEPROM, or the like that stores measurement data (raw data or processed data subjected to various processes) obtained by the sleep sensor 1 in a volatile or non-volatile manner. In this way, with the configuration having the measurement data storage means, for example, the accumulated data in the storage unit 519 can be collectively transmitted every predetermined period, so that the communication unit 520 is intermittently transmitted. It becomes possible to be in a standby state, and as a result, the battery driving time of the sleep sensor 501 can be extended.

  The communication unit 520 uses the measurement data (raw data, processed data subjected to various processes, or stored data in the storage unit 519) obtained by the sleep sensor 501 as an external information terminal 502 (data server or personal computer). Etc.) via wireless or wired transmission. In particular, if the measurement data obtained by the sleep sensor 501 is wirelessly transmitted to the information terminal 502, it is not necessary to connect the sleep sensor 501 and the information terminal 502 with a wire. It is possible to perform real-time transmission of measurement data without doing so. In particular, when the sleep sensor 501 has a waterproof structure, it is desirable to adopt a wireless transmission method as an external transmission method of measurement data from the viewpoint of completely eliminating external terminals of the sleep sensor 501. Note that when the measurement data is wirelessly transmitted to the information terminal 502 at a short distance (several meters to several tens of meters), a Bluetooth (registered trademark) wireless communication module or the like can be suitably used as the communication unit 520. Further, when measuring data is transmitted to the remote information terminal 502 via the Internet or the like, a wireless LAN module or the like can be suitably used as the communication unit 520.

  The power supply unit 521 includes a battery and a DC / DC converter, converts an input voltage from the battery into a desired output voltage, and supplies the output voltage to each unit of the sleep sensor 501. Thus, with the battery-driven sleep sensor 501, it is not necessary to connect an external power supply cable when measuring the sleep state, and thus it is possible to measure the sleep state without restricting the behavior of the subject. Become. In addition, as said battery, it is desirable to use the secondary battery (A lithium ion secondary battery, an electric double layer capacitor, etc.) which can be charged repeatedly. Thus, if the secondary battery is used as the battery, troublesome battery replacement work is not necessary, and the convenience of the sleep sensor 501 can be improved. Further, as a power supply method from the outside during battery charging, a contact power supply method using a USB cable or the like may be used, or a non-contact power supply such as an electromagnetic induction method, an electric field coupling method, and a magnetic field resonance method. It may be a method. However, when the sleep sensor 501 has a waterproof structure, it is desirable to adopt a non-contact power supply method as an external power supply method from the viewpoint of completely eliminating the external terminals of the sleep sensor 501.

  As described above, if a physical condition management system including the sleep sensor 501 attached to the subject and the information terminal 502 that performs analysis and log acquisition of the measurement data acquired by the sleep sensor 501 is constructed, the sleep sensor 501 itself Without unnecessarily enhancing the functions, it is possible to monitor the daily sleep state of the subject and perform appropriate physical condition management. Further, if data obtained from a large number of subjects are collected by the information terminal 502, a statistical analysis or the like can be performed.

  In addition, although it is desirable to leave the detailed analysis of the measurement data acquired by the sleep sensor 501 to the external information terminal 502 for the reasons described above, the sleep state of the subject is analyzed from the measurement data acquired by the sleep sensor 501. Thus, it is very useful to provide the control unit 515 with a function of driving the display unit 516 and the speaker 517.

  For example, the control unit 515 may be configured to drive the display unit 516 and the speaker 517 by determining the REM sleep / non-REM sleep of the subject from measurement data (pulse rate, pulse fluctuation, etc.) regarding the subject's pulse wave. For example, it is possible to provide the subject with a comfortable wake-up by outputting wake-up music or environmental sounds (such as a bird's chirping sound or water murmuring sound) from the speaker 517 in accordance with the subject's REM sleep. Become. Further, the control unit 515 may determine the sleep depth of the subject from the measurement data related to the pulse wave of the subject, and drive the display unit 516 and the speaker 517.

  In addition, the control unit 515 may be configured to drive the display unit 516 and the speaker 517 by determining the subject's apnea syndrome (sleep quality) from the measurement data regarding the blood oxygen saturation of the subject. For example, if an alarm sound is output from the speaker 517 at the onset of apnea syndrome, the subject can be forcibly awakened or the subject's abnormality can be notified to the surroundings.

  In addition, the control unit 515 may be configured to drive the display unit 516 and the speaker 517 by determining the sleep depth of the subject from measurement data relating to the body temperature or body surface temperature of the subject. For example, when the sleep state of the subject becomes shallow and the body temperature rises, it is possible to provide the subject with a comfortable sleep by outputting alarm music or environmental sound from the speaker 517.

  The control unit 515 may be configured to determine the sleep depth of the subject from the measurement data related to the body movement of the subject and drive the display unit 516 and the speaker 517. For example, when the sleep state of the subject becomes shallow and the body motion increases, the wake-up music or environmental sound is output from the speaker 517, so that the subject can be provided with a comfortable sleep awakening.

  In addition, the control unit 515 may be configured to drive the display unit 516 and the speaker 517 by determining the state of the subject (snoring, bruxism, and the like) from the measurement data related to the sound and voice emitted by the subject and the ambient sound of the subject. For example, by outputting an alarm sound from the speaker 517 when the subject's snoring becomes serious, the subject can be forcibly awakened or the abnormality of the subject can be notified to the surroundings.

  In the above example, the configuration in which the drive control of the display unit 516 and the speaker 517 incorporated in the sleep sensor 501 according to the sleep state of the subject is given as an example, but the targets of the drive control by the control unit 515 are these However, it is conceivable to remotely control a home electric appliance provided outside the sleep sensor 501.

  FIG. 40 is a schematic diagram illustrating a configuration example of a home appliance control system using the sleep sensor 501. In the home appliance control system of this configuration example, the electric curtain A1, the audio device A2, the lighting device A3, the television A4, the air conditioner A5, and the bedding (in accordance with the sleep state of the subject determined using the sleep sensor 501) A6 is controlled.

  According to the home appliance control system of this configuration example, for example, when the subject wakes up, the electric curtain A1 is opened, the wake-up music is played from the audio device A2, the lighting device A3 is turned on, and the news channel is selected on the television A4. The interior of the bedroom can be set to an appropriate temperature with the air conditioner A5, and the bedding A6 can be adjusted to a state in which the subject can easily wake up (such as reclining adjustment of the electric bed or pressure adjustment of the air mat).

  Thus, according to the home appliance control system of this configuration example, the sleep sensor 501 and the various home appliances A1 to A6 can be linked to provide a comfortable sleep to the subject.

  In addition, although FIG. 40 gave and demonstrated the structural example by which household appliances A1-A6 are directly controlled from the sleep sensor 501, the structure of a household appliance control system is not limited to this, For example, a sleep sensor When an information terminal 502 (see FIG. 39) for analyzing various measurement data acquired in 501 is prepared, the home appliances A1 to A6 may be controlled from the information terminal 502.

  FIG. 41A is a schematic diagram illustrating a first wearing example (forehead wearing type) of the sleep sensor 501. FIG. In FIG. 41A, the main body of the sleep sensor 501 is arranged at the center part (position where the eyebrow of the subject is in contact) of the eye mask type housing 501X (see the broken line in the figure). As described above, if the sleep sensor 501 is disposed between the eyebrows where the capillaries are concentrated, the optical sensor unit 511 can stably measure the pulse wave and the blood oxygen saturation, and thus the sleep state measurement. The accuracy can be increased. The eye mask type housing 501X also functions as a light shielding member that covers the sleep sensor 501. By setting it as such a structure, since the optical sensor part 511 becomes difficult to receive the influence of external light, it becomes possible to measure a sleep state stably. Further, since the eye mask type housing 501X can relax the subject as its original function, it is not necessary to apply excessive stress to the subject during measurement of the sleep state.

  FIG. 41B is a schematic diagram illustrating a second wearing example (ear wearing type) of the sleep sensor 501. In FIG. 41B, a sensor unit 501Y attached to the subject's outer ear and a main unit 501Z attached to the subject's collar and chest are separately provided. Various sensor units 511 to 514 are accommodated in the sensor unit 501Y, and the remaining components 515 to 521 are accommodated in the main unit 501Z. With such a configuration, the sensor unit 501Y attached to the outer ear of the subject can be reduced in size, so that the subject does not feel uncomfortable. In particular, since the outer ear is a part with less body movement than fingers and arms, the output signal of the optical sensor unit 511 is not easily affected by body movement noise, and the pulse wave and blood oxygen saturation are measured with high accuracy. Can be performed. As for the form of the sensor unit 501Y, a general form of an earphone (an inner ear type, a canal type, a clip type, etc.) may be adopted, or an earplug type inserted into the external ear canal may be adopted. It does not matter (see FIGS. 36A to 36D and FIG. 37).

<Consideration on output wavelength>
In the experiment, in the so-called reflection type pulse wave sensor, the output wavelength of the light emitting part is λ1 (infrared: 940 nm), λ2 (green: 630 nm), and λ3 (blue: 468 nm), and the output intensity (driving) of the light emitting part is driven. The behavior when the (current value) was changed to 1 mA, 5 mA, and 10 mA was investigated. As a result, in the visible light region having a wavelength of about 600 nm or less, the absorption coefficient of oxygenated hemoglobin HbO ₂ is increased, and the peak intensity of the measured pulse wave is increased, so that the waveform of the pulse wave can be obtained relatively easily. I understood.

In the pulse oximeter that detects the oxygen saturation of arterial blood, the difference between the absorption coefficient (solid line) of oxygenated hemoglobin HbO ₂ and the absorption coefficient (broken line) of deoxygenated hemoglobin Hb is maximized. Although the wavelength (around 700 nm) is widely used as the output wavelength of the light emitting unit, the above experimental results are obtained when considering use as a pulse wave sensor (particularly a so-called reflection type pulse wave sensor). It can be said that it is desirable to use a visible light region having a wavelength of 600 nm or less as the output wavelength of the light emitting unit as shown in FIG.

  However, when both the pulse wave and the blood oxygen saturation are detected using a single optical sensor unit, the wavelength in the near infrared region may be used as before.

<Summary>
Hereinafter, various inventions disclosed in the present specification will be described in general terms.

[First invention]
Of the various inventions disclosed in the present specification, the pulse wave sensor according to the first invention detects the intensity of light transmitted through the living body by irradiating the living body with light from the light emitting section. A pulse wave sensor provided with an optical sensor unit for acquiring pulse wave data by means of the optical sensor unit, wherein the optical sensor unit includes a bowl-shaped case, a first region on which the light emitting unit is placed, and the light receiving unit. And a light-shielding wall that is divided into second regions on which the part is placed (first-first configuration).

  In the pulse wave sensor having the configuration 1-1, a configuration in which a relationship of H1> H2 is established between the height H1 of the light shielding wall and the height H2 of the light emitting unit (first) -2).

  In the pulse wave sensor having the configuration 1-2, the offset distance ΔH (= H1−H2) obtained by subtracting the height H2 of the light emitting unit from the height H1 of the light shielding wall is 0 mm <ΔH <2 mm. A certain configuration (1-3 configuration) is preferable.

  In the pulse wave sensor having the configuration 1-2 or 1-3, a relationship of H2> H3 is established between the height H2 of the light emitting unit and the height H3 of the light receiving unit. (1-4 configuration).

  Further, in the pulse wave sensor having any one of the first to first to fourth configurations, the inter-element distance W1 between the light emitting unit and the light receiving unit is 0.2 mm ≦ W1 ≦ 0.8 mm ( The first to fifth configurations) may be used.

  Further, in the pulse wave sensor having any one of the first to first to first-5 configurations, the optical sensor unit may be configured to have a condensing lens above the light emitting unit (configuration 1-6). .

  Further, in the pulse wave sensor having any one of the first to first to sixth configurations, the first region is formed by a first lid member having a first opening smaller than the light emitting region of the light emitting unit. It is good to make it the structure (1-7 structure) covered.

  Further, in the pulse wave sensor having any one of the first to first to seventh configurations, the second region is covered with a second lid member having a second opening larger than the light receiving region of the light receiving unit. It is preferable to adopt the configuration (1-8 configuration).

  Further, in the pulse wave sensor having any one of the first to first to eighth configurations, at least one of the light emitting unit and the light receiving unit includes a color filter that selectively allows only a predetermined wavelength component to pass therethrough. (Structure 1-9) may be used.

  Moreover, in the pulse wave sensor having the configuration of any one of 1-1 to 1-9, each of the light emitting unit and the light receiving unit includes a substrate, a light emitting chip and a light receiving chip mounted on the substrate, respectively. And a sealing body for sealing the light-emitting chip and the light-receiving chip (structure 1-10).

  Further, in the pulse wave sensor having any one of the first to first to tenth configurations, the case is embedded in the main body portion so as to protrude from the main body portion carrying the optical sensor portion ( It is preferable to use the 1-11th configuration.

  In the pulse wave sensor having any one of the first to first to eleventh configurations, the output wavelength of the light emitting unit may be configured to belong to the visible light region of about 600 nm or less (first to twelfth configuration). .

[Second invention]
Of the various inventions disclosed in the present specification, the pulse wave sensor according to the second invention is configured to irradiate a living body with light from a light emitting unit and transmit the intensity of the light transmitted through the living body to the light receiving unit. A pulse wave sensor comprising: an optical sensor unit that acquires pulse wave data by detection; and a main body unit that carries the optical sensor unit, wherein the main body unit moves toward the living body when attached to the living body. The optical sensor portion is provided on the surface of the main body portion in the vicinity of the point of application where the pressing force toward the living body is maximum (2-1). It is said that.

  In the pulse wave sensor having the configuration of (2-1), the main body portion is connected to a belt at both ends, and the optical sensor portion is within 10 mm from the connection point between the main body portion and the belt. It is good to use the configuration provided in (2-2 configuration).

  Further, in the pulse wave sensor having the configuration of (2-1), the main body is configured such that a spring hinge is connected to a first end and a second end is an open end, and the optical sensor is It is good to make it the structure (2-3 structure) provided within 10 mm from the 2nd end of a main-body part.

  Further, in the pulse wave sensor having the configuration of any one of the 2-1 to 2-3, the optical sensor portion has an application point on the surface of the main body portion at which the pressing force to the living body becomes maximum. A plurality of configurations (second to fourth configuration) may be provided in the vicinity region.

  Further, in the pulse wave sensor having any one of the configurations of the 2-1 to the 2-4, the output wavelength of the light emitting unit is configured to belong to a visible light region of about 600 nm or less (2-5 configuration). Good.

[Third invention]
Of the various inventions disclosed in the present specification, the pulse wave sensor according to the third aspect of the invention relates to the intensity of the light transmitted through the living body by irradiating the living body with light from the light emitting section. A pulse wave sensor comprising: an optical sensor unit that acquires pulse wave data by detection; and a filter unit that performs a filtering process on an output signal of the optical sensor unit, wherein the filter unit includes: A high-pass filter circuit that removes the low-frequency component superimposed on the output signal, a voltage follower circuit that transmits the output signal of the high-pass filter circuit to a subsequent stage, and a low-pass filter that removes the high-frequency component superimposed on the output signal of the voltage follower circuit Circuit, a first amplifier circuit for amplifying the output signal of the low-pass filter circuit, and a low-frequency component and a high-frequency component superimposed on the output signal of the first amplifier circuit are removed. A band-pass filter circuit that is configured to have a second amplifying circuit for amplifying the output signal of the band-pass filter circuit (3-1 configuration).

  In the pulse wave sensor having the configuration 3-1 described above, the high-pass filter circuit may be configured as a primary CR high-pass filter circuit having a cutoff frequency of 0.66 Hz (configuration 3-2). .

  In the pulse wave sensor having the configuration of 3-1 or 3-2, the low-pass filter circuit is a second-order CR low-pass filter circuit having a cutoff frequency of 0.26 Hz (3-3). (Configuration).

  Further, in the pulse wave sensor having any one of the configurations of 3-1 to 3-3, the bandpass filter circuit is a sixth-order band filter circuit having a pass frequency band of 0.80 to 2.95 Hz. It is good to set it as a structure (3-4th structure).

  Further, in the pulse wave sensor having the configuration of any one of the 3-1 to 3-4, the filter unit includes an intermediate voltage generation circuit that divides a power supply voltage to generate an intermediate voltage, and the high-pass filter circuit The low-pass filter circuit, the first amplifier circuit, the band-pass filter circuit, and the second amplifier circuit are all configured to operate using the intermediate voltage as a reference voltage (configuration 3-5). Good.

  Further, in the pulse wave sensor having the configuration of any one of the 3-1 to the 3-5, the output wavelength of the light emitting unit is configured to belong to the visible light region of about 600 nm or less (configuration 3-6). Good.

[Fourth Invention]
Of the various inventions disclosed in this specification, a pulse wave sensor according to a fourth invention includes a housing attached to the outer ear and a light provided from the light emitting unit to the outer ear. And a light sensor that acquires pulse wave data by detecting the intensity of light transmitted through the living body and returned by the light receiving unit (configuration 4-1).

  In the pulse wave sensor having the fourth configuration, it is preferable that the casing has a configuration having a speaker (fourth configuration).

  In addition, the pulse wave sensor having the configuration 4-2 may be configured (a configuration 4-3) having a control unit that controls the output operation of the speaker in accordance with the pulse wave data.

  The pulse wave sensor having any one of the 4-1 to 4-3 configurations may have a configuration (fourth configuration) having a communication unit that transmits the pulse wave data to the information terminal.

  Further, in the pulse wave sensor having the configuration of any one of the 4-1 to 4-4, the housing has a configuration that fits a hollow portion surrounded by the tragus and the antitragus (fourth-fourth). 5 configuration).

  In the pulse wave sensor having the fourth to fifth configuration, the light receiving unit may be configured to be closer to the ear canal than the light emitting unit (fourth to sixth configuration).

  Further, in the pulse wave sensor having any one of the configurations of the 4-1 to 4-4, the casing may have a configuration (fourth to seventh configuration) having a shape covering the auricle.

  Further, in the pulse wave sensor having the fourth to seventh structure, when the case has a structure (fourth to eighth structure) having a protrusion member that carries the optical sensor unit on a surface facing the auricle. Good.

  In the pulse wave sensor having any one of the configurations of the 4-1 to the 4th-4, the casing may have a configuration having a clip member suspended on the auricle (configuration 4-9).

  In the pulse wave sensor having the fourth to ninth configuration, the clip member may have a configuration (fourth to tenth configuration) in which the optical sensor unit is supported at a location where the clip member comes into contact with the auricle.

  In the pulse wave sensor having the configuration 4-1, the casing may have a configuration (a configuration 4-11) having an earplug structure for measuring a pulse wave inside the ear canal.

  Further, in the pulse wave sensor having the configuration of any one of 4-1 to 4-11, the optical sensor unit includes a bowl-shaped case, the first region on which the light emitting unit is placed, and the case. It is good to make it the structure (4th-12th structure) which has the light-shielding wall divided | segmented into the 2nd area | region in which a light-receiving part is mounted.

  In the pulse wave sensor having the fourth to twelfth configuration, H1> H2> H3 between the height H1 of the light shielding wall, the height H2 of the light emitting unit, and the height H3 of the light receiving unit. It is preferable to adopt a configuration (fourth to thirteenth configuration) that establishes the relationship.

  In the pulse wave sensor having the configuration 4-13, the case may be configured to be embedded in a shape protruding from the housing (configuration 4-14).

  Further, in the pulse wave sensor having any one of the configurations of the 4-1 to the 4-14, the optical sensor unit is configured to have a buffer member between the housing (configuration 4-15). Good.

  Further, in the pulse wave sensor having any one of the configurations of the 4-1 to the 4-15, the output wavelength of the light emitting unit is configured to belong to a visible light region of about 600 nm or less (configuration 4-16). Good.

[Fifth Invention]
Of the various inventions disclosed in this specification, the sleep sensor according to the fifth invention is an optical sensor that acquires measurement data related to a subject's pulse wave or measurement data related to a pulse wave and blood oxygen saturation. A temperature sensor unit that acquires measurement data related to the body temperature or body surface temperature of the subject, an acceleration sensor unit that acquires measurement data related to the body movement of the subject, and sounds or voices or sounds of the surrounding environment that the subject emits A microphone that obtains measurement data relating to, a control unit that comprehensively controls the operation of the entire sleep sensor, a display unit that outputs an image, a speaker that outputs audio, an operation unit that accepts an input operation, A storage unit that stores measurement data, a communication unit that transmits measurement data to an information terminal that analyzes the sleep state of the subject, and power supply to each unit of the sleep sensor It is configured to have a power supply unit, the performing (5-1 configuration).

  In addition, in the sleep sensor which consists of a 5th-1 structure, when the said control part analyzes each measurement data and makes it the structure (the structure of a 5-2) provided with the function which analyzes the sleep state of the said test subject. Good.

  Further, in the sleep sensor having the configuration 5-2, the control unit determines at least one of the REM sleep / non-REM sleep and the sleep depth of the subject from the measurement data related to the pulse wave of the subject, the display unit, It is good to set it as the structure (5-3 structure) which drives the said speaker or external household appliances.

  Further, in the sleep sensor having the configuration of 5-2 or 5-3, the control unit determines the apnea syndrome of the subject from the measurement data regarding the blood oxygen saturation of the subject, and the display unit, It is good to set it as the structure (5-4 structure) which drives the said speaker or external household appliances.

  Further, in the sleep sensor having any one of configurations 5-2 to 5-4, the control unit determines the sleep depth of the subject from measurement data related to the body temperature or the body surface temperature of the subject, and the display unit The speaker or an external home appliance may be driven (5-5 configuration).

  Further, in the sleep sensor having any one of the configurations of 5-2 to 5-5, the control unit determines the sleep depth of the subject from measurement data related to the body movement of the subject, and the display unit, the speaker, Or it is good to set it as the structure (5-6th structure) which drives an external household appliance.

  Further, in the sleep sensor having any one of the configurations of Nos. 5-2 to 5-6, the control unit determines the state of the subject from measurement data relating to sounds or voices generated by the subject or sounds of the surrounding environment, It is good to set it as the structure (5-7 structure) which drives a display part, the said speaker, or an external household appliance.

  Further, in the sleep sensor having any one of the first to fifth to seventh configurations, the optical sensor unit irradiates light from the light emitting unit to the living body of the subject, and then returns through the living body. It is preferable to have a configuration (5-8 configuration) in which measurement data relating to the pulse wave of the subject or measurement data relating to the pulse wave and blood oxygen saturation is acquired by detecting the intensity of light at the light receiving unit.

  Further, in the sleep sensor having the configuration of No. 5-8, the optical sensor unit includes a bowl-shaped case, a first region in which the light emitting unit is mounted, and a light receiving unit in which the light receiving unit is mounted. It is good to make it the structure (5-9 structure) which has the light-shielding wall divided | segmented into 2 area | regions.

  In the sleep sensor having the configuration 5-9, the relationship H1> H2> H3 is established between the height H1 of the light shielding wall, the height H2 of the light emitting unit, and the height H3 of the light receiving unit. (5-10 configuration) is preferable.

  Further, in the sleep sensor having the fifth to tenth configuration, the case may be configured to be embedded in a form protruding from a housing that carries the optical sensor unit (the fifth to eleventh configuration).

  Moreover, the sleep sensor which consists of a 5-11th structure WHEREIN: The said optical sensor part is good to set it as the structure (5th-12th structure) which has a buffer member between the said housing | casings.

  Further, in the sleep sensor having any one of the fifth to eighth to twelfth configurations, the output wavelength of the light emitting unit may be configured to belong to the visible light region of about 600 nm or less (the fifth to thirteenth configuration). .

  Moreover, the physical condition management system which concerns on 5th invention is the information sensor which analyzes the sleep data which consists of the structure in any one of 5-1 to 5-13, and the measurement data acquired by the said sleep sensor, and log acquisition (The 5-14th configuration).

  Moreover, the household appliance control system which concerns on 5th invention is based on the sleep state of the test subject determined using the sleep sensor which consists of the structure in any one of 5-1 to 5-13, and the said sleep sensor or the said information terminal. It is set as the structure (5-15 structure) which has the household appliances driven according to it.

  In the home appliance control system having the configuration 5-15, the home appliance is at least one of an electric curtain, an audio device, a lighting device, a television, an air conditioner, and a bedding (5-16). (Configuration).

[Sixth Invention]
Of the various inventions disclosed in the present specification, the pulse wave sensor according to the sixth aspect of the invention is characterized in that the light receiving unit determines the intensity of the light transmitted from the light emitting unit to the living body and transmitted through the living body. An optical sensor unit to detect, a main body unit carrying the optical sensor unit, a belt attached to the main body unit and wound around the living body, and provided between the optical sensor unit and the main body unit It is set as the structure (6-1 structure) which has a buffer member.

  The pulse wave sensor having the configuration 6-1 further includes a printed wiring board on which the optical sensor unit is mounted, and the buffer member is provided between the printed wiring board and the main body part. It is good to use the structure (6-2 structure).

  In addition, the pulse wave sensor having the configuration of 6-1 or 6-2 further includes a contact member (sixth configuration) provided around the optical sensor unit and in close contact with the living body. Good.

  Further, in the pulse wave sensor having the sixth structure, the contact member may be provided with a gap (the sixth structure) between the optical sensor section.

  In addition, the pulse wave sensor having any one of the configurations of 6-2 to 6-4 further includes a protection member that covers at least one of the front surface and the back surface of the printed wiring board (configuration 6-5). It is good to.

  In the pulse wave sensor having the above-described configuration 6-5, at least one of the contact member and the protection member may be configured to be black (configuration 6-6).

  Also, in the pulse wave sensor having any one of the configurations of 6-2 to 6-6, the belt and the printed wiring board are attached to the main body with a gap that does not contact each other ( It is preferable to use the 6-7th configuration.

  In the pulse wave sensor having any one of the sixth to sixth to seventh configurations, the main body portion may be configured to have a low center of gravity structure (sixth to eighth configuration).

  The pulse wave sensor having any one of the sixth to sixth to eighth configurations may have a configuration (sixth to ninth configuration) having a filter unit that performs a filtering process on the output signal of the optical sensor unit. .

  In the pulse wave sensor having the sixth to ninth configuration, the filter unit includes a band-pass filter circuit that removes a low-frequency component and a high-frequency component from the output signal of the optical sensor unit (the sixth to tenth components). Configuration).

  In the pulse wave sensor having the sixth to tenth configuration, the band pass filter circuit is a sixth-order operational amplifier multiple feedback type band filter circuit having a pass frequency band of 0.7 to 3.0 Hz (sixth -11 configuration).

  Further, the pulse wave sensor disclosed in the present specification includes an optical sensor unit that irradiates a living body with light from a light emitting unit and detects the intensity of light transmitted through the living body with a light receiving unit, and the light emitting unit is provided as an external device. A configuration (6-12th configuration) is provided that includes a pulse driving unit that performs pulse driving with higher luminance than light, and a filter unit that performs detection processing on the output signal of the optical sensor unit to extract a pulse wave signal. ing.

  In the pulse wave sensor having the sixth to twelfth configuration, when the wavelength characteristic of the light receiving unit is designed to match the wavelength characteristic of the light emitting unit (the sixth to thirteenth configuration). Good.

  Further, in the pulse wave sensor having the sixth to sixth or sixth to sixth configurations, the pulse driving unit is configured to pulse-drive the light emitting unit with a duty of 1/10 to 1/100 (the sixth to fourteenth). Configuration).

  In the pulse wave sensor having any one of the sixth to twelfth to sixth to fourteenth configurations, the filter unit detects a detection process for the output signal of the optical sensor unit, and amplifies the output signal of the detection circuit. A first amplifying circuit, a bandpass filter circuit that removes a low-frequency component and a high-frequency component from the output signal of the first amplifying circuit, a low-pass filter circuit that removes a high-frequency component from the output signal of the bandpass filter circuit, It is preferable to have a configuration (a 6-15 configuration) having a second amplification circuit that amplifies the output signal of the low-pass filter circuit.

  Further, in the pulse wave sensor having the sixth to fifteenth configuration, the bandpass filter circuit is a sixth-order operational amplifier multiple feedback type band filter circuit having a pass frequency band of 0.7 to 3.0 Hz (sixth -16 configuration).

  In the pulse wave sensor having the sixth to sixth or sixth to sixth configurations, the low-pass filter circuit is a first-order CR low-pass filter circuit having a cutoff frequency of 1.45 Hz (No. 6-17). (Configuration).

  Further, in the pulse wave sensor having any one of the sixth to fifth to sixteenth configurations, the filter unit includes an intermediate voltage generation circuit that divides a power supply voltage to generate an intermediate voltage, and the detection circuit, The first amplifier circuit, the band-pass filter circuit, the low-pass filter circuit, and the second amplifier circuit may all be configured to operate using the intermediate voltage as a reference voltage (configuration 6-18).

  Further, in the pulse wave sensor having any one of the configurations of 6-1 to 6-18, the output wavelength of the light emitting unit is configured to belong to a visible light region of about 600 nm or less (configuration 6-19). Good.

<Other variations>
Various configurations of the invention disclosed in the present specification can be variously modified within the scope of the invention, in addition to the embodiment described above. That is, the above-described embodiment is an example in all respects and should not be considered as limiting, and the technical scope of the present invention is not the description of the above-described embodiment, but the claims. It should be understood that all modifications that come within the meaning and range of equivalents of the claims are included.

  Various inventions disclosed in the present specification can be used as a technique for enhancing the convenience of a pulse wave sensor and a sleep sensor, and include healthcare support devices, game devices, music devices, and pet communication. It can be applied to various fields such as tools and anti-sleeping devices for vehicle drivers.

1 Pulse wave sensor 2 Living body (wrist, ear, etc.)
DESCRIPTION OF SYMBOLS 10 Main body unit 10a Main body part 10b Printed wiring board 10c Buffer member 10d Adhesion member 10e Protection member 11 Optical sensor part 11a Case 11b Light-shielding wall 11c Condensing lens 11d, 11e Cover member 11f Buffer member (rubber, synthetic sponge, etc.)
11z Translucent plate 11A Light emitting diode (light emitting part)
11B Phototransistor (light receiving part)
12 Filter Unit 13 Control Unit 14 Display Unit 15 Communication Unit 16 Power Supply Unit 17 Pulse Drive Unit (Modulation Circuit)
20 belt 30 spring hinge x light emitting part (light emitting chip)
y Light receiving part (light receiving chip)
X light emitting part X1 substrate X2 light emitting chip X3 sealing body X4 wire X5 conductor X6 color filter Y light receiving part Y1 substrate Y2 light receiving chip Y3 sealing body Y4 wire Y5 conductor Y6 color filter 100 current / voltage conversion circuit 110 primary CR High-pass filter circuit 120 Amplifier circuit 130 Primary CR low-pass filter circuit 140 Amplifier circuit 200 Current / voltage conversion circuit 210 Primary CR high-pass filter circuit 220 Voltage follower circuit 230 Secondary CR low-pass filter circuit 240 Amplifier circuit 250 Sixth-order band-pass filter circuit 260 Amplifier circuit 270 Intermediate voltage generation circuit 300 Current / voltage conversion circuit 310 Detection circuit (demodulation circuit)
320 Amplifier circuit 330 Sixth-order bandpass filter circuit 340 Primary CR low-pass filter circuit 350 Amplifier circuit 360 Intermediate voltage generation circuit R1 to R55 Resistor C1 to C43 Capacitor D1, D2 Diode OP1 to OP14 Operational amplifier P1 P channel type MOS field effect transistor IC1 Semiconductor device ST1 to ST3 Schmitt trigger E Outer ear E1 Scapular fossa E2 Ear ring E3 Ear ring E4 Ear tragus E5 Ear canal E6 Upper ear ring leg E7 Trigular fossa E8 Lower ear ring leg E9 Ear concha E10 Ear tragus E11 Tragus notch E12 Ear 401 Pulse wave sensor (portable audio player, hearing aid)
401X Earphone (Headphone)
401Y Main unit 402 Information terminal (data server, personal computer, etc.)
403 Network 410 Housing 410x Projection member 410y Clip member 411 Optical sensor unit 411A Light emitting unit 411B Light receiving unit 412 Speaker 413 Driver 414 Code 415 Connector 420 Housing 421 Control unit 422 Operation unit 423 Display unit 424 Storage unit 425 Communication unit 426 Power supply unit 427 Filter unit 501 Sleep sensor 501X Eye mask type housing 501Y Sensor unit 501Z Main unit 502 Information terminal (data server, personal computer, etc.)
511 Optical sensor unit 512 Temperature sensor unit 513 Acceleration sensor unit 514 Microphone 515 Control unit 516 Display unit 517 Speaker 518 Operation unit 519 Storage unit 520 Communication unit 521 Power supply unit A1 Electric curtain A2 Audio equipment A3 Lighting equipment A4 Television A5 Air conditioner A6 Bedding (electric bed, air mat, etc.)

Claims (19)

A light sensor unit that irradiates the living body with light from the light emitting unit and detects the intensity of light transmitted through the living body with a light receiving unit;
A main body carrying the photosensor unit;
A belt attached to the main body and wound around the living body;
A buffer member provided between the optical sensor unit and the main body unit;
A pulse wave sensor comprising: It further has a printed wiring board on which the optical sensor unit is mounted,
The buffer member is provided between the printed wiring board and the main body.
The pulse wave sensor according to claim 1.   The pulse wave sensor according to claim 1, further comprising a contact member that is provided around the optical sensor unit and is in close contact with the living body.   The pulse wave sensor according to claim 3, wherein the contact member is provided with a gap between the optical sensor unit and the optical sensor unit.   The pulse wave sensor according to any one of claims 2 to 4, further comprising a protective member that covers at least one of a front surface and a back surface of the printed wiring board.   The pulse wave sensor according to claim 5, wherein at least one of the contact member and the protection member is black.   The pulse wave sensor according to any one of claims 2 to 6, wherein the belt and the printed wiring board are attached to the main body with a gap that does not contact each other.   The pulse wave sensor according to any one of claims 1 to 7, wherein the main body portion has a low center of gravity structure.   The pulse wave sensor according to any one of claims 1 to 8, further comprising a filter unit that performs a filtering process on an output signal of the optical sensor unit.   The pulse wave sensor according to claim 9, wherein the filter unit includes a band-pass filter circuit that removes a low-frequency component and a high-frequency component from an output signal of the optical sensor unit.   11. The pulse wave sensor according to claim 10, wherein the band pass filter circuit is a sixth-order operational amplifier multiple feedback type band filter circuit having a pass frequency band of 0.7 to 3.0 Hz. A light sensor unit that irradiates the living body with light from the light emitting unit and detects the intensity of light transmitted through the living body with a light receiving unit;
A pulse driving unit for driving the light emitting unit with a higher luminance than external light; and
A filter unit for extracting a pulse wave signal by performing a detection process on the output signal of the optical sensor unit;
A pulse wave sensor comprising:   The pulse wave sensor according to claim 12, wherein the wavelength characteristic of the light receiving unit is designed to match the wavelength characteristic of the light emitting unit.   14. The pulse wave sensor according to claim 12, wherein the pulse driving unit causes the light emitting unit to be pulse-driven with a duty of 1/10 to 1/100. The filter unit is
A detection circuit for performing detection processing on the output signal of the optical sensor unit;
A first amplifier circuit for amplifying the output signal of the detector circuit;
A bandpass filter circuit for removing a low frequency component and a high frequency component from the output signal of the first amplifier circuit;
A low-pass filter circuit for removing high-frequency components from the output signal of the band-pass filter circuit;
A second amplifier circuit for amplifying the output signal of the low-pass filter circuit;
The pulse wave sensor according to any one of claims 12 to 14, characterized by comprising:   The pulse wave sensor according to claim 15, wherein the band pass filter circuit is a sixth-order operational amplifier multiple feedback type band filter circuit having a pass frequency band of 0.7 to 3.0 Hz.   The pulse wave sensor according to claim 15 or 16, wherein the low-pass filter circuit is a primary CR low-pass filter circuit having a cut-off frequency of 1.45 Hz.   The filter unit includes an intermediate voltage generation circuit that divides a power supply voltage to generate an intermediate voltage, the detection circuit, the first amplifier circuit, the bandpass filter circuit, the lowpass filter circuit, and the second 18. The pulse wave sensor according to claim 15, wherein each of the amplifier circuits operates using the intermediate voltage as a reference voltage.   The pulse wave sensor according to any one of claims 1 to 18, wherein an output wavelength of the light emitting unit belongs to a visible light region of approximately 600 nm or less.