JP2017169690A - Biological information measuring device and electronic equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a biological information measuring device and electronic equipment capable of performing more accurate noise removal.SOLUTION: A biological information measuring device includes a light emitting element 11, three or more light receiving elements 12, 13, and 14, and a signal processing part. The three or more light receiving elements are arranged at least at three places whose distances from the light emitting element are different respectively in a predetermined direction from the light emitting element on a wiring board 10. The signal processing part derives a fourth detection signal in which an impact of a noise component is reduced, by the calculation based on a first detection signal, a second detection signal, and a third detection signal. The first detection signal is a signal detected by the first light receiving element relatively close to the light emitting element. The second detection signal is a signal detected by the second light receiving element relatively far from the light emitting element. The third detection signal is a signal detected by the third light receiving element between the first light receiving element and the second light receiving element.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to a biological information measuring device and an electronic apparatus.

  In recent years, with the evolution of wearable devices and the spread of constant wireless connection, watch-type or wristband-type devices equipped with a pulse sensor are on the market. Photoplethysmography (PPG) is widely used for pulse sensors in these devices.

JP2015-188498A JP 2009-39568 A

  In the photoelectric volumetric pulse wave method, signal fluctuations due to various noises occur, so noise removal with higher accuracy is required. Further, even when a method similar to the photoelectric volume pulse wave method is used for biological information other than the pulse, more accurate noise removal is required. It is desirable to provide a biological information measuring apparatus and electronic device that can perform noise removal with higher accuracy.

  A first biological information measuring device according to an embodiment of the present disclosure includes a light emitting element, three or more light receiving elements, and a signal processing unit. The light emitting element is disposed on the wiring board and emits light to the subject. The three or more light receiving elements are arranged on at least three places on the wiring board in different directions from the light emitting elements in a predetermined direction. Each light receiving element receives light from the subject. The signal processing unit derives a fourth detection signal in which the influence of the noise component is reduced by a calculation based on the first detection signal, the second detection signal, and the third detection signal. Here, the first detection signal is a signal detected by the first light receiving element relatively closer to the light emitting element among the three or more light receiving elements. The second detection signal is a signal detected by a second light receiving element that is relatively far from the light emitting element among the three or more light receiving elements. The third detection signal is a signal detected by the third light receiving element between the first light receiving element and the second light receiving element among the three or more light receiving elements. The signal processing unit derives biological information of the subject having a correlation with the fourth detection signal based on the derived fourth detection signal.

  A first electronic device according to an embodiment of the present disclosure includes the first biological information measurement device described above.

  In the first biological information measuring device and the first electronic device according to the embodiment of the present disclosure, three light receiving elements having different distances from the light emitting elements are provided. Thereby, for example, in the first light receiving element, a detection signal containing a lot of noise generated on the skin of the subject is obtained. Further, for example, in the second light receiving element, a detection signal containing a lot of noise generated in the subcutaneous tissue of the subject can be obtained. In addition, for example, in the third light receiving element, a detection signal including a signal component related to biological information of the subject and noise generated in the epidermis and subcutaneous tissue of the subject is obtained. Therefore, a detection signal in which the influence of the noise component is reduced can be derived by performing an operation based on these three detection signals.

  The second biological information measurement device according to an embodiment of the present disclosure includes a light receiving element, three or more light emitting elements, and a signal processing unit. The light receiving element is disposed on the wiring board and receives light from the subject. The three or more light emitting elements are disposed on at least three places on the wiring board in different directions from the light receiving element in a predetermined direction. Three or more light emitting elements emit light to the subject. The signal processing unit sequentially causes each light emitting element to emit light. The signal processing unit derives a fourth detection signal in which the influence of the noise component is reduced by a calculation based on the first detection signal, the second detection signal, and the third detection signal. Here, the first detection signal is a signal detected by the light receiving element when the first light emitting element relatively closer to the light receiving element among the three or more light emitting elements emits light. The second detection signal is a signal detected by the light receiving element when the second light emitting element that is relatively far from the light receiving element among the three or more light emitting elements emits light. The third detection signal is a signal detected by the light receiving element when the third light emitting element between the first light emitting element and the second light emitting element among the three or more light emitting elements emits light. The signal processing unit derives biological information of the subject having a correlation with the fourth detection signal based on the derived fourth detection signal.

  A second electronic device according to an embodiment of the present disclosure includes the second biological information measurement device.

  In the second biological information measuring device and the second electronic device according to an embodiment of the present disclosure, three light emitting elements having different distances from the light receiving element are provided. Thereby, for example, when the first light emitting element relatively close to the light receiving element emits light, a detection signal containing a lot of noise generated on the skin of the subject is obtained. Further, for example, when the second light emitting element that is relatively distant from the light receiving element emits light, a detection signal including a lot of noise generated in the subcutaneous tissue of the subject is obtained. Further, for example, when the third light emitting element between the first light emitting element and the second light emitting element emits light, the signal component related to the biological information of the subject and the noise generated in the epidermis and subcutaneous tissue of the subject A detection signal including is obtained. Therefore, a detection signal in which the influence of the noise component is reduced can be derived by performing an operation based on these three detection signals.

  A third biological information measuring device according to an embodiment of the present disclosure includes a light receiving element, three or more light emitting elements, and a signal processing unit. The light receiving element is disposed on the wiring board and receives light from the subject. The three or more light emitting elements are arranged on at least three places on the wiring board in a predetermined direction from the light receiving elements, or the distances from the light receiving elements are equal to each other or substantially equal to each other. The three or more light emitting elements have different emission wavelengths and emit light to the subject. The signal processing unit sequentially causes each light emitting element to emit light. The signal processing unit derives a fourth detection signal in which the influence of the noise component is reduced by a calculation based on the first detection signal, the second detection signal, and the third detection signal. Here, the first detection signal is a signal detected by the light receiving element when the first light emitting element relatively closer to the light receiving element among the three or more light emitting elements emits light. The second detection signal is a signal detected by the light receiving element when the second light emitting element that is relatively far from the light receiving element among the three or more light emitting elements emits light. The third detection signal is a signal detected by the light receiving element when the third light emitting element between the first light emitting element and the second light emitting element among the three or more light emitting elements emits light. The signal processing unit derives biological information of the subject having a correlation with the fourth detection signal based on the derived fourth detection signal.

  A third electronic device according to an embodiment of the present disclosure includes the third biological information measuring device.

  In the third biological information measuring apparatus and the third electronic device according to an embodiment of the present disclosure, three light emission units having different emission wavelengths at locations where the distances from the light receiving elements are equal to or substantially equal to each other. An element is provided. Thereby, for example, when the first light-emitting element having a relatively short emission wavelength emits light, a detection signal containing a lot of noise generated on the skin of the subject is obtained. Further, for example, when the second light emitting element having a relatively long emission wavelength emits light, a detection signal containing a lot of noise generated in the subcutaneous tissue of the subject can be obtained. In addition, for example, when a third light emitting element having a light emission wavelength between the light emission wavelength of the first light emitting element and the light emission wavelength of the second light emitting element emits light, Detection signals including noise generated in the epidermis and subcutaneous tissue of the skin. Therefore, a detection signal in which the influence of the noise component is reduced can be derived by performing an operation based on these three detection signals.

  According to the first biological information measuring device and the first electronic device of the embodiment of the present disclosure, the three light receiving elements having different distances from the light emitting elements are provided. By performing a calculation based on the three detected signals, a detection signal in which the influence of the noise component is reduced can be derived. Therefore, more accurate noise removal can be performed.

  According to the second biological information measuring device and the second electronic device according to the embodiment of the present disclosure, the three light emitting elements having different distances from the light receiving element are provided. By performing an operation based on the three detection signals detected when light is emitted, a detection signal with reduced influence of noise components can be derived. Therefore, more accurate noise removal can be performed.

  According to the third biological information measuring device and the third electronic device of the embodiment of the present disclosure, the respective emission wavelengths are different from each other at locations where the distances from the light receiving elements are equal to or substantially equal to each other. Since the three light emitting elements are provided, a detection signal in which the influence of the noise component is reduced is derived by performing an operation based on the three detection signals detected when the three light emissions are sequentially emitted. can do. Therefore, more accurate noise removal can be performed.

  In addition, the effect of this indication is not necessarily limited to the effect described here, Any effect described in this specification may be sufficient.

It is a figure showing an example of the plane composition of the pulse wave measuring device of a 1st embodiment of this indication. It is a figure showing an example of the cross-sectional structure of the pulse wave measuring device of FIG. It is a figure showing an example of the usage example of the pulse-wave measuring apparatus of FIG. It is a figure showing an example of the functional block of the pulse wave measuring device of FIG. It is a figure showing an example of the detection principle of the pulse wave measuring device of FIG. It is a figure showing an example of the relationship between the distance from a light emitting element, and AC / DC of a detection signal. It is a figure showing an example of the plane composition of the pulse wave measuring device of a 2nd embodiment of this indication. It is a figure showing an example of the functional block of the pulse wave measuring device of Drawing 7. It is a figure showing an example of the light emission timing in the pulse-wave measuring apparatus of FIG. It is a figure showing an example of the detection principle of the pulse wave measuring device of FIG. It is a figure showing an example of the plane composition of the pulse wave measuring device of a 3rd embodiment of this indication. It is a figure showing an example of the functional block of the pulse wave measuring device of Drawing 11. It is a figure showing an example of the plane composition of the pulse wave measuring device of a 4th embodiment of this indication. It is a figure showing an example of the functional block of the pulse wave measuring device of FIG. It is a figure showing an example of the plane composition of the pulse wave measuring device of a 5th embodiment of this indication. It is a figure showing an example of the functional block of the pulse wave measuring device of FIG. It is a figure showing an example of the light emission timing in the pulse-wave measuring apparatus of FIG. It is a figure showing one modification of the plane composition of the pulse wave measuring device of Drawing 1. It is a figure showing one modification of the plane composition of the pulse wave measuring device of Drawing 7. It is a figure showing an example of the electronic device which is an application example of the pulse wave measuring device of each said embodiment.

Hereinafter, modes for carrying out the present disclosure will be described in detail with reference to the drawings. The description will be given in the following order.

1. 1st Embodiment (pulse wave measuring device) ... FIGS. 1-6
1. Example in which one light emitting element and three light receiving elements are provided. Second Embodiment (Pulse Wave Measuring Device) ... FIGS. 7 to 10
2. Example in which three light emitting elements and one light receiving element are provided. Third Embodiment (Pulse Wave Measuring Device) ... FIG. 11 and FIG.
3. Example in which one light emitting element and one line sensor are provided Fourth Embodiment (Pulse Wave Measuring Device) ... FIGS. 13 and 14
4. Example in which one light emitting element and one image sensor are provided Fifth embodiment (pulse wave measuring device) ... FIGS. 15 to 17
5. Example in which three light emitting elements and one light receiving element having different wavelengths are provided. Modified example of first and second embodiments (pulse wave measuring device)
Modification A: Example in which one light emitting element and four or more light receiving elements are provided. FIG.
Modification B: Example in which four or more light emitting elements and one light receiving element are provided. FIG.
7). Application example (electronic equipment) ... FIG.
Examples in which the pulse wave measuring devices of the above embodiments and their modifications are applied to electronic devices such as watches

<1. First Embodiment>
[Constitution]
FIG. 1 illustrates an example of a planar configuration of a pulse wave measurement device 1 (biological information measurement device) according to the first embodiment of the present disclosure. FIG. 2 illustrates an example of a cross-sectional configuration along the line segment LN of the pulse wave measuring device 1 of FIG. FIG. 3 shows a usage example of the pulse wave measuring device 1 of FIG. FIG. 4 shows an example of functional blocks of the pulse wave measuring device 1 of FIG.

  The pulse wave measuring device 1 is a device that detects a pulse wave (pulse) that is one of biological information of the subject 100. The pulse wave measuring device 1 includes, for example, a wiring board 10, one light emitting element 11 and three light receiving elements 12, 13, 14 disposed on the wiring board 10. The wiring board 10 supports one light emitting element 11 and three light receiving elements 12, 13, and 14 and is electrically connected to one light emitting element 11 and three light receiving elements 12, 13, and 14.

  For example, the wiring substrate 10 is formed by forming a wiring layer on a resin substrate, a resin film, or a glass substrate. The light emitting element 11 is configured by a semiconductor light source such as an LED (light emitting diode) or an LD (Laser Diode). The light emitting element 11 emits light L1 having a light emission wavelength in the visible region, near infrared region, or infrared region. The light emitting element 11 emits light L1 having a component in the normal direction of the wiring board 10. Thereby, when the pulse wave measuring device 1 is attached to the arm of the subject 100 as shown in FIG. 3, the light emitting element 11 emits light L <b> 1 toward the arm of the subject 100. Each of the light receiving elements 12, 13, and 14 is configured by, for example, a PD (Photo Diode). Each of the light receiving elements 12, 13, and 14 is preferably configured to output detection signals that are equal to each other when light having the same amplitude and frequency is input. Each of the light receiving elements 12, 13, and 14 is preferably composed of, for example, the same material, structure, and size.

  One light emitting element 11 and three light receiving elements 12, 13, 14 are arranged (mounted) on one surface of the wiring board 10. The three light receiving elements 12, 13, and 14 have three different distances from the light emitting element 11 in a predetermined direction (for example, a direction parallel to the line segment LN in the drawing) from the light emitting element 11 on the wiring board 10. Is located. When the pulse wave measuring device 1 is attached to the arm, the wiring board 10, the light emitting element 11, the light receiving elements 12, 13, and 14 are provided in the housing 20, and the belt 19 is attached to the housing 20. . When the pulse wave measuring device 1 is attached to the arm, the arrangement direction of the three light receiving elements 12, 13, and 14 (for example, the direction parallel to the line segment LN in the drawing) is parallel or substantially parallel to the extending direction of the arm. It is preferable that In this case, when the arm is moved, a large change in the degree of adhesion between the housing 20 and the arm can be suppressed.

  The “predetermined direction” does not only mean a direction along the line segment LN in the drawing. The “predetermined direction” means, for example, when the observer views the light emitting element 11 from the normal direction of the wiring board 10, the right side of the light emitting element 11, the left side of the light emitting element 11, the upper side of the light emitting element 11, or the light emission. This is a concept including a rough direction such as the lower side of the element 11. Therefore, for example, the three light receiving elements 12, 13, and 14 may be arranged on the line segment LN in the figure, or the line segment LN in the figure within a range that can be recognized from the light emitting element 11 as a predetermined direction. You may arrange | position in the position remove | deviated from. A more specific arrangement of the three light receiving elements 12, 13, and 14 will be described in detail later.

  The light receiving element 12 is a light receiving element (first light receiving element) that is disposed relatively closer to the light emitting element 11 among the three light receiving elements 12, 13, and 14. When light from the subject 100 (specifically, light scattered from the subject 100 out of the light emitted from the light emitting element 11) is input, the light receiving element 12 responds to the input light. The detection signal d1 (first detection signal) is output. The light receiving element 14 is a light receiving element (second light receiving element) that is disposed relatively far from the light emitting element 11 among the three light receiving elements 12, 13, and 14. When light from the subject 100 (specifically, light scattered from the subject 100 out of the light emitted from the light emitting element 11) is input, the light receiving element 14 responds to the input light. The detection signal d3 (second detection signal) is output. The light receiving element 13 is a light receiving element (third light receiving element) between the light receiving element 12 and the light receiving element 14. When light from the subject 100 (specifically, light scattered from the subject 100 out of the light emitted from the light emitting element 11) is input, the light receiving element 13 responds to the input light. The detection signal d2 (third detection signal) is output.

  The pulse wave measuring device 1 further includes, for example, a signal processing unit 15, a storage unit 16, a communication unit 17, and a display unit 18. At least one of the communication unit 17 and the display unit 18 may be omitted as necessary. For example, the signal processing unit 15, the storage unit 16, and the communication unit 17 are disposed (mounted) on the back surface of the wiring substrate 10 (the surface of the wiring substrate opposite to the light emitting element 11 side). Thereby, compared with the case where the signal processing part 15, the memory | storage part 16, and the communication part 17 are arrange | positioned on the upper surface (surface by the side of the light emitting element 11) of the wiring board 10, the pulse wave measuring device 1 is small. Can be realized. The display part 18 is arrange | positioned in the space of the back surface side of the wiring board 10, for example. The display unit 18 is connected to the signal processing unit 15 via, for example, FPC (Flexible Printed Circuits).

  The communication unit 17 communicates with a portable communication terminal such as a smartphone using, for example, proximity wireless communication such as Bluetooth (registered trademark). The communication unit 17 detects the detection signal 15A (fourth detection signal) derived by the signal processing unit 15 or the biological information of the subject 100 derived by the signal processing unit 15 by communication with a portable communication terminal such as a smartphone. Exchange 15B. The display unit 18 includes, for example, an LCD (Liquid Crystal Display) or an OELD (Organic Electroluminescence Display). The display unit 18 displays the detection signal 15A input from the signal processing unit 15, the biological information 15B of the subject 100, and the like.

  The storage unit 16 can store various programs and various data files. The storage unit 16 stores a processing program 16A and a coefficient 16B. The storage unit 16 can further store various data generated by executing the processing program 16A. Examples of such data include the detection signal 15A and the biological information 15B of the subject 100. The storage unit 16 is configured by, for example, a non-volatile memory, and is configured by, for example, an EEPROM (Electrically Erasable Programmable Read-Only Memory), a flash memory, a resistance change type memory, or the like.

  The processing program 16A is for causing the processor (the signal processing unit 15) to execute a series of procedures for deriving the biological information of the subject 100 (specifically, the pulse wave (pulse) of the subject 100). is there. The processing program 16A includes a calculation procedure based on the three detection signals detected by the three light receiving elements 12, 13, and 14. The coefficient 16B includes, for example, coefficients a, b, c applied to the detection signal d1, coefficients d, e, f applied to the detection signal d2, and coefficients g, h, i applied to the detection signal d3. The coefficients a, b, and c correct the amplitude of the detection signal d1. The coefficients d, e, and f correct the amplitude of the detection signal d2. The coefficients g, h, i correct the amplitude of the detection signal d3. The coefficients a, b, c, d, e, f, g, h, and i may be values obtained by calibration at the time of shipment of the pulse wave measuring device 1 or the pulse wave measuring device 1. It may be a value obtained by performing calibration by the user after shipment from the factory.

  For example, the signal processing unit 15 reads the processing program 16A from the storage unit 16 based on an instruction from the user, and executes the read contents. The signal processing unit 15 executes a series of procedures for deriving the biological information 15B of the subject 100 (specifically, information related to the pulse wave (pulse) of the subject 100).

  The signal processing unit 15 derives a detection signal 15A in which the influence of the noise component is reduced by calculation based on the three detection signals d1, d2, and d3 detected by the three light receiving elements 12, 13, and 14. Further, the signal processing unit 15 derives the biological information 15B of the subject 100 having a correlation with the detection signal 15A based on the derived detection signal 15A. The signal processing unit 15 derives the detection signal 15A by subtracting the noise component from the detection signal d2 based on the detection signal d1 and the detection signal d3. Below, the detection principle of the pulse wave measuring apparatus 1 is demonstrated first, and the signal processing method in the signal processing part 15 is demonstrated after that.

(Detection principle)
FIG. 5 shows an example of the detection principle of the pulse wave measuring device 1. As shown in FIG. 5, the inside of the subject 100 is arranged in the order of the epidermis, dermis, and subcutaneous tissue from the surface of the living body. The light L1 emitted from the light emitting element 11 is incident on the inside of the subject 100 from the surface of the living body, is scattered by each layer of the epidermis, dermis, and subcutaneous tissue, and the scattered light is received by the three light receiving elements 12, 13, and 14. Is done.

  The light receiving element 13 is disposed at a position where light scattered by the dermis where many capillaries that affect pulse fluctuation are present is dominantly received and the signal quality is the best. . Here, the signal quality is evaluated by, for example, AC / DC, which is a parameter representing the quality of the fluctuation component of the pulse. FIG. 6 shows an example of the relationship between the distance from the light emitting element 11 and the AC / DC of the detection signal. FIG. 6 shows that the optimum distance between the light emitting element 11 and the light receiving element 13 is between 3.5 mm and 4.5 mm.

  The light receiving element 12 is a position where light passing through only the epidermis or light reflected from the surface is dominantly received, and a position where light reaching the inside of the living body such as subcutaneous tissue is difficult to be received (position close to the light emitting element 11). ). The optimum distance between the light emitting element 11 and the light receiving element 12 is 3.5 mm or less. When the light receiving element 12 is arranged at a position close to the light emitting element 11, the body surface noise (when the light receiving element 12 is displaced between the casing of the pulse wave measuring device 1 and the subject 100) ( The noise generated at the surface of the living body is dominantly received.

  The light receiving element 14 is a position where light passing through only the epidermis or light reflected from the surface is not easily received, and a position where light reaching the inside of the living body such as a subcutaneous tissue is dominantly received (position far from the light emitting element 11). ). The optimum distance between the light emitting element 11 and the light receiving element 14 is 4.5 mm or more. When the light receiving element 14 is arranged at a position far from the light emitting element 11, the light receiving element 14 predominantly receives internal noise (noise generated inside the living body) generated when the inside of the living body moves.

The light receiving element 13 is arranged at an optimum position where the signal quality (AC / DC) is the best. However, when the light receiving element 13 is arranged at such a position, the light receiving element 13 simultaneously receives body surface noise and body noise. For this reason, the signal deteriorates when noise is generated due to the displacement between the housing and the living body or the movement inside the living body. Therefore, signal deterioration due to noise is reduced by removing the noise component from the detection signal acquired by the light receiving element 13 using the body surface noise component and the body noise component acquired by the light receiving elements 12 and 14. The components received by the respective light receiving elements 12, 13, and 14 are as follows.

In equations (1), (2), and (3), N1 represents a body surface noise component, N2 represents a body noise component, and S represents a pulse fluctuation component. The coefficients a, b, c, d, e, f, g, h, i represent the amplitude of each component. Considering the positional relationship of the light receiving elements 12, 13, and 14 with respect to the light emitting element 11, in the formula (1), the body surface noise component is dominant, so b and c are very small values. In Equation (3), since the internal noise component is dominant, g and h are very small values. In formula (2), there are significant amounts of any component. Here, when Expressions (1), (2), and (3) are represented by determinants, the following Expression (4) is obtained.

Each part of the left side and the right side of Expression (4) is expressed as the following Expressions (5) to (7).

Therefore, Expression (4) is expressed as Expression (8) below by Expressions (5), (6), and (7).

In Expression (8), [PD] is a signal obtained by the light receiving element. [M] is a coefficient. [V] is a body surface noise component N1, a body noise component N2, and a pulse fluctuation component S to be obtained. Therefore, the signal processing unit 15 derives the pulse fluctuation component S in which noise is reduced, that is, the detection signal 15A, by performing a matrix operation shown in the following Expression (9). In Expression (9), [M] ⁻¹ is a coefficient, which may be fixed at the time of product shipment, or may be updated after learning for each individual after shipment.

[effect]
Next, the effect of the pulse wave measuring device 1 will be described. In recent years, with the evolution of wearable devices and the spread of constant wireless connection, watch-type or wristband-type devices equipped with a pulse sensor are on the market. Photoplethysmography (PPG) is widely used for pulse sensors in these devices. In the photoelectric volumetric pulse wave method, signal fluctuations due to various noises occur, so noise removal with higher accuracy is required. Further, even when a method similar to the photoelectric volume pulse wave method is used for biological information other than the pulse, more accurate noise removal is required. However, the conventional method has room for improvement in noise removal.

  On the other hand, in the pulse wave measuring apparatus 1 of the present embodiment, three light receiving elements 12, 13, and 14 having different distances from the light emitting element 11 are provided. Thereby, for example, in the light receiving element 12, a detection signal d <b> 1 including a lot of noise generated in the skin of the subject 100 is obtained. Further, for example, in the light receiving element 14, a detection signal d <b> 3 including a lot of noise generated in the subcutaneous tissue of the subject 100 is obtained. For example, in the light receiving element 13, a detection signal d <b> 2 including a signal component related to the biological information 15 </ b> B of the subject 100 and noise generated in the epidermis and subcutaneous tissue of the subject 100 is obtained. Therefore, by performing an operation based on these three detection signals d1, d2, and d3, it is possible to derive the detection signal 15A in which the influence of the noise component is reduced. Therefore, more accurate noise removal can be performed.

  In the pulse wave measuring apparatus 1 of the present embodiment, the detection signal 15A is derived by subtracting the noise component from the detection signal d2 based on the detection signal d1 and the detection signal d3. Thereby, noise removal with higher accuracy can be performed.

  In the pulse wave measuring apparatus 1 of the present embodiment, photodiodes are used as the light receiving elements 12, 13, and 14. Therefore, noise removal with higher accuracy can be performed with a simple configuration.

<2. Second Embodiment>
Next, the pulse wave measurement device 2 (biological information measurement device) according to the second embodiment of the present disclosure will be described. FIG. 7 illustrates an example of a planar configuration of the pulse wave measuring device 2 according to the present embodiment. FIG. 8 shows an example of functional blocks of the pulse wave measuring device 2 of FIG.

  In the present embodiment, in the above embodiment, the light emitting element 21 is disposed at the position of the light receiving element 12, the light emitting element 22 is disposed at the position of the light receiving element 13, and the light emitting element 23 is disposed at the position of the light receiving element 14. The light receiving element 24 is disposed at the position of the light emitting element 11.

  The pulse wave measuring device 2 is a device that detects a pulse wave (pulse) that is one of biological information of the subject 100. The pulse wave measuring device 2 includes, for example, a wiring board 10, three light emitting elements 21, 22, 23 and one light receiving element 24 arranged on the wiring board 10. The wiring board 10 supports the three light emitting elements 21, 22, 23 and one light receiving element 24 and is electrically connected to the three light emitting elements 21, 22, 23 and one light receiving element 24.

  The light emitting elements 21, 22, and 23 are constituted by semiconductor light sources such as LEDs and LDs, for example. Each of the light emitting elements 21, 22, and 23 emits light L1 having a light emission wavelength in the visible region, the near infrared region, or the infrared region. Each of the light emitting elements 21, 22, and 23 is preferably configured to emit light having the same amplitude and frequency. Each of the light emitting elements 21, 22, and 23 is preferably configured with, for example, the same material, structure, and size. Each light emitting element 21, 22, 23 emits light L 2, L 3, L 4 having a component in the normal direction of the wiring board 10. Thereby, when the pulse wave measuring device 2 is attached to the arm of the subject 100 as shown in FIG. 3, each light emitting element 21, 22, 23 is directed toward the arm of the subject 100 with the light L <b> 2, L <b> 3. , L4. The light receiving element 24 is configured by, for example, a PD (Photo Diode).

  The three light emitting elements 21, 22 and 23 and the one light receiving element 24 are arranged (mounted) on one surface of the wiring board 10. The three light emitting elements 21, 22, and 23 have three different distances from the light receiving element 24 in a predetermined direction (for example, a direction parallel to the line segment LN in the drawing) from the light receiving element 24 on the wiring board 10. Is located. When the pulse wave measuring device 2 is attached to the arm, the wiring board 10, the light emitting elements 21, 22, 23 and the light receiving element 2 are provided in the housing 20, and the belt 19 is attached to the housing 20. . When the pulse wave measuring device 2 is attached to the arm, the arrangement direction of the three light emitting elements 21, 22, and 23 (for example, the direction parallel to the line segment LN in the figure) is parallel or substantially parallel to the extending direction of the arm. It is preferable that In this case, when the arm is moved, a large change in the degree of adhesion between the housing 20 and the arm can be suppressed.

The “predetermined direction” does not only mean a direction along the line segment LN in the drawing. The “predetermined direction” means, for example, when the observer views the light receiving element 24 from the normal direction of the wiring board 10, the right side of the light receiving element 24, the left side of the light receiving element 24, the upper side of the light receiving element 24, or the light receiving This is a concept including a rough direction such as the lower side of the element 24. Accordingly, the three light emitting elements 21, 22, and 23 may be disposed, for example, on the line segment LN in the drawing, or the line segment LN in the drawing within a range that can be recognized as a predetermined direction from the light receiving element 24. You may arrange | position in the position remove | deviated from. A more specific arrangement of the three light emitting elements 21, 22, and 23 will be described in detail later.

  The light-emitting element 21 is a light-emitting element (first light-emitting element) that is disposed closer to the light-receiving element 24 among the three light-emitting elements 21, 22, and 23. When light from the subject 100 (specifically, light scattered from the subject 100 out of the light emitted from the light emitting element 21) is input, the light receiving element 24 responds to the input light. The detection signal d4 (t1) (first detection signal) is output. The light-emitting element 23 is a light-emitting element (second light-emitting element) that is disposed relatively far from the light-receiving element 24 among the three light-emitting elements 21, 22, and 23. When light from the subject 100 (specifically, light scattered from the subject 100 out of the light emitted from the light emitting element 23) is input to the light receiving element 24, the light receiving element 24 responds to the input light. The detection signal d4 (t3) (second detection signal) is output. The light emitting element 22 is a light emitting element (third light emitting element) between the light emitting element 21 and the light emitting element 23. When light from the subject 100 (specifically, light scattered from the subject 100 out of the light emitted from the light emitting element 22) is input, the light receiving element 24 responds to the input light. The detection signal d4 (t2) (third detection signal) is output.

  The processing program 16A is for causing the processor (the signal processing unit 15) to execute a series of procedures for deriving the biological information of the subject 100 (specifically, the pulse wave (pulse) of the subject 100). is there. The processing program 16A includes a calculation procedure based on the three detection signals d4 (t1), d4 (t2), and d4 (t3) detected sequentially in time by the light receiving element 24. The coefficient 16B includes, for example, coefficients a, b, c applied to the detection signal d4 (t1), coefficients d, e, f applied to the detection signal d4 (t2), and coefficients g, h applied to the detection signal d4 (t3). , I. The coefficients a, b, and c correct the amplitude of the detection signal d4 (t1). The coefficients d, e, and f are for correcting the amplitude of the detection signal d4 (t2). The coefficients g, h, i correct the amplitude of the detection signal d4 (t3). The coefficients a, b, c, d, e, f, g, h, i may be values obtained by calibration when the pulse wave measuring device 2 is shipped from the factory, or the coefficients of the pulse wave measuring device 2 It may be a value obtained by performing calibration by the user after shipment from the factory.

  For example, the signal processing unit 15 reads the processing program 16A from the storage unit 16 based on an instruction from the user, and executes the read contents. The signal processing unit 15 executes a series of procedures for deriving the biological information 15B of the subject 100 (specifically, information related to the pulse wave (pulse) of the subject 100).

  The signal processing unit 15 causes the light emitting elements 21, 22, and 23 to emit light sequentially, and the three detection signals d4 (t1), d4 (t2), and d4 (t3) detected sequentially in time by the light receiving element 24. The detection signal 15A in which the influence of the noise component is reduced is derived by the calculation based on. There is no particular limitation on the order in which the light emitting elements 21, 22, and 23 emit light, but FIG. 9 illustrates the timing of light emission when the light emitting elements 21, 22, and 23 are made to emit light in order from the light receiving element 24. Has been. Further, the signal processing unit 15 derives the biological information 15B of the subject 100 having a correlation with the detection signal 15A based on the derived detection signal 15A. The signal processing unit 15 derives the detection signal 15A by subtracting the noise component from the detection signal d4 (t2) based on the detection signal d4 (t1) and the detection signal d4 (t3).

  The light emitting element 22 is a position where the light receiving element 24 dominantly receives light scattered by the dermis where there are many capillaries that affect pulse fluctuations, and at a position where the signal quality is the best. Be placed. The optimum distance between the light emitting element 22 and the light receiving element 24 is, for example, between 3.5 mm and 4.5 mm.

  The light emitting element 21 is a position where the light receiving element 24 dominantly receives light passing through only the epidermis or light reflected from the surface, and is a position where the light reaching the inside of the living body such as subcutaneous tissue is difficult to receive (light receiving element 24). (Position close to). The optimum distance between the light emitting element 21 and the light receiving element 24 is, for example, 3.5 mm or less. When the light emitting element 21 is disposed at a position close to the light receiving element 24, when the housing of the pulse wave measuring device 2 and the subject 100 are displaced when the light emitting element 21 emits light. The generated body surface noise (noise generated on the surface of the living body) is predominantly received.

  The light emitting element 23 is a position that is difficult to receive light that has passed through only the epidermis or light that has been reflected from the surface, and that receives light that has reached the inside of the living body, such as subcutaneous tissue (position far from the light receiving element 24). Placed in. The optimum distance between the light emitting element 23 and the light receiving element 24 is, for example, 4.5 mm or more. In the case where the light emitting element 23 is arranged at a position far from the light receiving element 24, when the light emitting element 23 emits light, internal noise (noise generated inside the living body) generated when the inside of the living body moves is dominant. Is received.

The light emitting element 22 is disposed at an optimum position where the signal quality (AC / DC) is the best. However, when the light emitting element 22 is arranged at such a position, the light receiving element 24 simultaneously receives body surface noise and body noise. For this reason, the signal deteriorates when noise is generated due to the displacement between the housing and the living body or the movement inside the living body. Therefore, using the body surface noise component and the in-body noise component acquired by the light receiving element 24 when the light emitting element 21 or the light emitting element 23 emits light, the light receiving element 24 acquires the light when the light emitting element 22 emits light. By removing a noise component from the detection signal, signal deterioration due to noise is reduced. The components received by the light receiving element 24 are as follows.

In Expression (10), since the body surface noise component is dominant, b and c are very small values. In Expression (12), since the internal noise component is dominant, g and h are very small values. In formula (11), there are significant amounts of any component. Here, when Expressions (10), (11), and (12) are represented by determinants, the following Expression (13) is obtained.

When the left and right sides of Expression (13) are expressed as Expressions (14), (6), and (7), respectively, Expression (13) can be expressed by Expressions (14), (6), and (7). It is expressed as equation (8). Therefore, the signal processing unit 15 derives the pulse fluctuation component S in which noise is reduced, that is, the detection signal 15A, by performing the matrix calculation shown in Expression (9). In Expression (9), [M] ⁻¹ may be fixed at the time of product shipment, or may be updated after learning for each individual after shipment.

[effect]
Next, the effect of the pulse wave measuring device 2 will be described. In the pulse wave measuring apparatus 2 of the present embodiment, three light emitting elements 21, 22, and 23 having different distances from the light receiving element 24 are provided. Thereby, for example, when the light emitting element 21 emits light, the detection signal d4 (t1) including a lot of noise generated in the epidermis of the subject 100 is obtained. Further, for example, when the light emitting element 23 emits light, the detection signal d4 (t3) including a lot of noise generated in the subcutaneous tissue of the subject 100 is obtained. For example, when the light emitting element 22 emits light, a detection signal d4 (t2) including a signal component related to the biological information 15B of the subject 100 and noise generated in the epidermis and subcutaneous tissue of the subject 100 is obtained. Therefore, by performing calculations based on these three detection signals d4 (t1), d4 (t2), and d4 (t3), it is possible to derive the detection signal 15A in which the influence of the noise component is reduced. Therefore, more accurate noise removal can be performed.

  Further, in the pulse wave measuring apparatus 2 of the present embodiment, the detection signal 15A is derived by subtracting the noise component from the detection signal d4 (t2) based on the detection signal d4 (t1) and the detection signal d4 (t3). Is done. Thereby, noise removal with higher accuracy can be performed.

  In the pulse wave measuring apparatus 2 of the present embodiment, a photodiode is used as the light receiving element 24. Therefore, noise removal with higher accuracy can be performed with a simple configuration.

<3. Third Embodiment>
Next, a pulse wave measurement device 3 (biological information measurement device) according to a third embodiment of the present disclosure will be described. FIG. 11 illustrates an example of a planar configuration of the pulse wave measuring device 3 according to the present embodiment. FIG. 12 shows an example of functional blocks of the pulse wave measuring device 3 of FIG.

  In the present embodiment, in the first embodiment, the light receiving unit 31A is disposed at the position of the light receiving element 12, the light receiving unit 31B is disposed at the position of the light receiving element 13, and the light receiving unit 31C is disposed at the position of the light receiving element 14. Is arranged. Further, the light receiving unit 31A, the light receiving unit 31B, and the light receiving unit 31C are each configured by a part of the light receiving units (one or a plurality of light receiving units) in the common line sensor 31 configured by a plurality of light receiving units arranged in a line. Has been.

  In the pulse wave measuring device 3 of the present embodiment, as in the first embodiment, three light receiving portions 31A, 31B, and 31C having different distances from the light emitting element 11 are provided. Thereby, for example, in the light receiving unit 31A, a detection signal d5 (x1) including a lot of noise generated in the epidermis of the subject 100 is obtained. Further, for example, in the light receiving unit 31C, a detection signal d5 (x3) including a lot of noise generated in the subcutaneous tissue of the subject 100 is obtained. For example, in the light receiving unit 31B, a detection signal d5 (x2) including a signal component related to the biological information 15B of the subject 100 and noise generated in the epidermis and subcutaneous tissue of the subject 100 is obtained. Therefore, by performing calculations based on these three detection signals d5 (x1), d5 (x2), and d5 (x3), it is possible to derive the detection signal 15A in which the influence of the noise component is reduced. For example, the calculation using the above equation (9) is performed. Therefore, more accurate noise removal can be performed.

  In the pulse wave measuring apparatus 3 of the present embodiment, the signal processing unit 15 is a signal in the detection signal d5 (x) for one line obtained by the line sensor 31 among the plurality of light receiving units included in the line sensor 31. The first light receiving unit corresponding to the peak value or a plurality of light receiving units including the first light receiving unit may be assigned as the light receiving unit 31B. In such a case, noise removal with higher accuracy can be performed.

<4. Fourth Embodiment>
Next, a pulse wave measurement device 4 (biological information measurement device) according to a fourth embodiment of the present disclosure will be described. FIG. 13 illustrates an example of a planar configuration of the pulse wave measuring device 4 of the present embodiment. FIG. 14 shows an example of functional blocks of the pulse wave measuring device 4 of FIG.

  In the present embodiment, in the first embodiment, the light receiving unit 41A is disposed at the position of the light receiving element 12, the light receiving unit 41B is disposed at the position of the light receiving element 13, and the light receiving unit 41C is disposed at the position of the light receiving element 14. Is arranged. Further, the light receiving unit 41A, the light receiving unit 41B, and the light receiving unit 41C are respectively formed by a part of the light receiving units (one or a plurality of light receiving units) in the common image sensor 41 configured by a plurality of light receiving units arranged in a matrix. It is configured. The image sensor 41 is, for example, a charge coupled device (CCD) image sensor or a complementary metal-oxide semiconductor (CMOS) image sensor.

  In the pulse wave measuring device 4 of the present embodiment, three light receiving portions 41A, 41B, and 41C having different distances from the light emitting element 11 are provided as in the first embodiment. Thereby, for example, in the light receiving unit 41A, the detection signal d6 (x1, y1) including a lot of noise generated in the epidermis of the subject 100 is obtained. Further, for example, in the light receiving unit 41C, a detection signal d6 (x3, y3) including a lot of noise generated in the subcutaneous tissue of the subject 100 is obtained. For example, in the light receiving unit 41B, a detection signal d6 (x2, y2) including a signal component related to the biological information 15B of the subject 100 and noise generated in the epidermis and subcutaneous tissue of the subject 100 is obtained. Therefore, the detection signal 15A in which the influence of the noise component is reduced is derived by performing an operation based on these three detection signals d6 (x1, y1), d6 (x2, y2), and d6 (x3, y3). Can do.

For example, the components received by the respective light receiving elements 41A, 41B, and 41C are expressed by the following equations (15), (16), and (17). Here, when Expressions (15), (16), and (17) are represented by determinants, Expression (18) is obtained. When the left and right sides of Expression (18) are expressed as Expressions (19), (6), and (7), respectively, Expression (18) can be expressed by Expressions (19), (6), and (7). It is expressed as equation (8). Therefore, the signal processing unit 15 derives the pulse fluctuation component S in which noise is reduced, that is, the detection signal 15A, by performing the matrix calculation shown in Expression (9). Therefore, also in this embodiment, noise removal with higher accuracy can be performed.

  In the pulse wave measuring device 4 of the present embodiment, the signal processing unit 15 includes a detection signal d6 (x, y) for one sheet obtained by the image sensor 41 among the plurality of light receiving units included in the image sensor 41. The first light receiving unit corresponding to the signal peak value at or a plurality of light receiving units including the first light receiving unit may be assigned as the light receiving unit 41B. In such a case, noise removal with higher accuracy can be performed.

<5. Fifth embodiment>
Next, a pulse wave measurement device 5 (biological information measurement device) according to a fifth embodiment of the present disclosure will be described. FIG. 15 illustrates an example of a planar configuration of the pulse wave measuring device 5 according to the present embodiment. FIG. 16 shows an example of functional blocks of the pulse wave measuring device 5 of FIG.

  In the present embodiment, instead of the light emitting elements 21, 22, and 23 in the second embodiment, the light emitting elements 51, 52, and 53 having different emission wavelengths have the same distance from the light receiving element 24. Or three places that are substantially equal to each other.

  The pulse wave measuring device 5 is a device that detects a pulse wave (pulse) that is one of biological information of the subject 100. The pulse wave measuring device 5 includes, for example, a wiring board 10, three light emitting elements 51, 52, 53 and one light receiving element 24 arranged on the wiring board 10. The wiring board 10 supports the three light emitting elements 51, 52, 53 and one light receiving element 24 and is electrically connected to the three light emitting elements 51, 52, 53 and one light receiving element 24.

  The three light emitting elements 51, 52, and 53 are configured by semiconductor light sources such as LEDs and LDs, for example. The three light emitting elements 51, 52, and 53 emit light L5, L6, and L7 having predetermined emission wavelengths from the visible region to the infrared region, respectively. The three light emitting elements 51, 52, 53 emit light L 5, L 6, L 7 having components in the normal direction of the wiring board 10. Thereby, when the pulse wave measuring device 5 is attached to the arm of the subject 100 as shown in FIG. 3, the three light emitting elements 51, 52, 53 are directed to the light L 5 toward the arm of the subject 100. Issue L6 and L7.

  Three light emitting elements 51, 52, 53 and one light receiving element 24 are arranged (mounted) on one surface of the wiring substrate 10. The three light emitting elements 51, 52, and 53 have the same distance from the light receiving element 24 in a predetermined direction (for example, a direction parallel to the line segment LN in the drawing) from the light receiving element 24 on the wiring board 10. Or it is arrange | positioned at three places substantially equal mutually. When the pulse wave measuring device 5 is attached to the arm, the wiring board 10, the light emitting elements 51, 52, 53 and the light receiving element 24 are provided in the housing 20, and the belt 19 is attached to the housing 20. . When the pulse wave measuring device 5 is attached to the arm, the direction in which the three light emitting elements 51, 52, 53 and the light receiving element 24 face each other (for example, the direction parallel to the line segment LN in the figure) is the arm. It is preferable to be parallel or substantially parallel to the extending direction. In this case, when the arm is moved, a large change in the degree of adhesion between the housing 20 and the arm can be suppressed.

  The “predetermined direction” does not only mean a direction along the line segment LN in the drawing. The “predetermined direction” means, for example, when the observer views the light receiving element 24 from the normal direction of the wiring board 10, the right side of the light receiving element 24, the left side of the light receiving element 24, the upper side of the light receiving element 24, or the light receiving This is a concept including a rough direction such as the lower side of the element 24. Accordingly, the three light emitting elements 51, 52, 53 may be arranged on a line segment orthogonal to the line segment LN in the figure, for example, or within a range that can be recognized as a predetermined direction from the light receiving element 24. You may arrange | position in the position remove | deviated from the inside line segment LN.

  The light emitting element 51 is a light emitting element (first light emitting element) having a relatively short emission wavelength among the three light emitting elements 51, 52, and 53. When light from the subject 100 (specifically, light scattered from the subject 100 out of the light emitted from the light emitting element 51) is input, the light receiving element 24 responds to the input light. The detection signal d7 (t1) (first detection signal) is output. The light emitting element 53 is a light emitting element (second light emitting element) having a relatively long emission wavelength among the three light emitting elements 51, 52, and 53. When light from the subject 100 (specifically, light scattered from the subject 100 out of the light emitted from the light emitting element 53) is input, the light receiving element 24 responds to the input light. The detection signal d7 (t3) (second detection signal) is output. The light emitting element 52 is a light emitting element (third light emitting element) having an emission wavelength between the emission wavelength of the light emitting element 51 and the emission wavelength of the light emitting element 53. When light from the subject 100 (specifically, light scattered from the subject 100 out of the light emitted from the light emitting element 52) is input to the light receiving element 24, the light receiving element 24 responds to the input light. The detection signal d7 (t2) (third detection signal) is output.

  The processing program 16A is for causing the processor (the signal processing unit 15) to execute a series of procedures for deriving the biological information of the subject 100 (specifically, the pulse wave (pulse) of the subject 100). is there. The processing program 16A includes a calculation procedure based on the three detection signals d7 (t1), d7 (t2), and d7 (t3) detected sequentially in time by the light receiving element 24. The coefficient 16B includes, for example, coefficients a, b, c applied to the detection signal d7 (t1), coefficients d, e, f applied to the detection signal d7 (t2), and coefficients g, h applied to the detection signal d7 (t3). , I. The coefficients a, b, and c correct the amplitude of the detection signal d7 (t1). The coefficients d, e, and f correct the amplitude of the detection signal d7 (t2). The coefficients g, h, i correct the amplitude of the detection signal d7 (t3). The coefficients a, b, c, d, e, f, g, h, and i may be values obtained by calibration at the time of shipment of the pulse wave measuring device 5 or the pulse wave measuring device 5. It may be a value obtained by performing calibration by the user after shipment from the factory.

  For example, the signal processing unit 15 reads the processing program 16A from the storage unit 16 based on an instruction from the user, and executes the read contents. The signal processing unit 15 executes a series of procedures for deriving the biological information 15B of the subject 100 (specifically, information related to the pulse wave (pulse) of the subject 100).

  The signal processing unit 15 causes the light emitting elements 51, 52, and 53 to emit light sequentially, and the three detection signals d7 (t1), d7 (t2), and d7 (t3) detected sequentially in time by the light receiving element 24. The detection signal 15A in which the influence of the noise component is reduced is derived by the calculation based on. There is no particular limitation on the order in which the light emitting elements 51, 52, and 53 emit light, but FIG. 17 illustrates the light emission timing when the light emitting elements 51, 52, and 53 emit light in the order of shorter emission wavelengths. ing. Further, the signal processing unit 15 derives the biological information 15B of the subject 100 having a correlation with the detection signal 15A based on the derived detection signal 15A. The signal processing unit 15 derives the detection signal 15A by subtracting the noise component from the detection signal d7 (t2) based on the detection signal d7 (t1) and the detection signal d7 (t3).

  The light emitting element 52 emits light with a light emission wavelength that causes the light receiving element 24 to dominantly receive light scattered by the dermis where there are many capillaries that affect pulse fluctuations, and has the best signal quality. Set to wavelength. The emission wavelength of the light emitting element 52 is, for example, 530 nm.

  The light emitting element 51 has a light emission wavelength that allows the light receiving element 24 to dominantly receive light that has passed through only the epidermis or light that has been reflected from the surface, and has a light emission wavelength that is difficult to receive light that has reached the inside of the living body, such as subcutaneous tissue. Emission wavelength). The emission wavelength of the light emitting element 51 is, for example, 430 nm. When the light emitting wavelength of the light emitting element 51 is set to a short light emitting wavelength, the light receiving element 24 causes body surface noise (when the casing of the pulse wave measuring device 5 and the subject 100 are displaced from each other) The noise generated at the surface of the living body is dominantly received.

  The light emitting element 53 has a light emission wavelength that makes it difficult to receive light that has passed through only the epidermis or light that has been reflected from the surface, and has a light emission wavelength (long light emission wavelength) that predominantly receives light that has reached the inside of the living body, such as subcutaneous tissue. Is set. The emission wavelength of the light emitting element 53 is, for example, 630 nm. When the light emitting wavelength of the light emitting element 53 is set to a long light emitting wavelength, the light receiving element 24 predominantly receives in-vivo noise (noise generated inside the living body) generated when the inside of the living body moves.

The light emission wavelength of the light emitting element 52 is set to an optimal value that provides the best signal quality (AC / DC). However, when the light emission wavelength of the light emitting element 52 is set to such a value, the light receiving element 24 simultaneously receives body surface noise and body noise. For this reason, the signal deteriorates when noise is generated due to the displacement between the housing and the living body or the movement inside the living body. Therefore, using the body surface noise component and the in-body noise component acquired by the light receiving element 24 when the light emitting element 51 or the light emitting element 53 emits light, the light receiving element 24 acquires it when the light emitting element 52 emits light. By removing a noise component from the detection signal, signal deterioration due to noise is reduced. The components received by the light receiving element 24 are as follows.

In Expression (20), since the body surface noise component is dominant, b and c are very small values. In the expression (22), since the internal noise component is dominant, g and h are very small values. In the formula (21), there is a considerable amount of any component. Here, when Expressions (20), (21), and (22) are represented by determinants, the following Expression (23) is obtained.

When the left and right sides of Expression (23) are expressed as Expressions (24), (6), and (7), respectively, Expression (23) can be expressed by Expressions (24), (6), and (7). It is expressed as equation (8). Therefore, the signal processing unit 15 derives the pulse fluctuation component S in which noise is reduced, that is, the detection signal 15A, by performing the matrix calculation shown in Expression (9). In Expression (9), [M] ⁻¹ may be fixed at the time of product shipment, or may be updated after learning for each individual after shipment.

[effect]
Next, the effect of the pulse wave measuring device 5 will be described. In the pulse wave measuring device 5 of the present embodiment, light emitting elements 51, 52, and 53 having different light emission wavelengths are provided. Thereby, for example, the detection signal d7 (t1) including a lot of noise generated in the epidermis of the subject 100 when the light emitting element 51 emits light is obtained. Further, for example, when the light emitting element 53 emits light, the detection signal d7 (t3) including a lot of noise generated in the subcutaneous tissue of the subject 100 is obtained. Further, for example, when the light emitting element 52 emits light, a detection signal d7 (t2) including a signal component related to the biological information 15B of the subject 100 and noise generated in the epidermis and subcutaneous tissue of the subject 100 is obtained. Therefore, by performing calculations based on these three detection signals d7 (t1), d7 (t2), and d7 (t3), it is possible to derive the detection signal 15A in which the influence of the noise component is reduced. Therefore, more accurate noise removal can be performed.

<6. Modified example of first and second embodiments>
Next, modifications of the first and second embodiments will be described. FIG. 18 shows a modification of the planar configuration of the pulse wave measuring device 1 of FIG. FIG. 19 shows a modification of the planar configuration of the pulse wave measuring device 2 of FIG.

  The pulse wave measuring device 1 of FIG. 18 includes four or more (six) light receiving elements 12, 12, 13, 13, 14, and 14. In the pulse wave measuring device 1 of FIG. 18, the signal processing device 15 is a set of (three) selected from four or more (six) light receiving elements 12, 12, 13, 13, 14, 14. The biological information 15B may be derived based on the detection signals d1, d2, and d3 obtained by the light receiving elements 12, 13, and 14.

  The pulse wave measuring device 2 in FIG. 19 includes four or more (six) light emitting elements 21, 21, 22, 22, 23, and 23. In the pulse wave measuring device 2 of FIG. 19, the signal processing device 15 is a set of (three) selected from four or more (six) light emitting elements 21, 22, 22, 22, 23, 23. The biological information 15B may be derived based on the detection signals d4 (t1), d4 (t2), and d4 (t3) obtained by the light emitting elements 21, 22, and 23.

  In the pulse wave measuring device 1 of FIG. 18, a set of (three) light receiving elements 12, 13, selected from four or more (six) light receiving elements 12, 12, 13, 13, 14, 14. The biological information 15B is derived based on the detection signals d1, d2, and d3 obtained in step 14. Thereby, in the pulse wave measuring device 1 of FIG. 18, the signal processing device 15 can output, for example, the biological information 15 </ b> B obtained from the combination with higher sensitivity. Therefore, more accurate noise removal can be performed.

  In the pulse wave measuring device 2 of FIG. 19, a set of (three) light emitting elements 21, 22 selected from four or more (six) light emitting elements 21, 22, 22, 22, 23, 23. Based on the detection signals d4 (t1), d4 (t2), and d4 (t3) obtained at 23, the biological information 15B is derived. Thereby, in the pulse wave measuring device 1 of FIG. 19, the signal processing device 15 can output the biological information 15B obtained from, for example, the combination with higher sensitivity. Therefore, more accurate noise removal can be performed.

<7. Application example>
Next, an example will be described in which the pulse wave measuring devices 1, 2, 3, 4, and 5 according to the above-described embodiments and modifications thereof are applied to an electronic device such as a wristwatch. FIG. 20 shows an example in which the pulse wave measuring devices 1, 2, 3, 4, and 5 of the above embodiments and their modifications are applied to an electronic device 6 such as a wristwatch.

  The electronic device 6 includes, for example, the pulse wave measuring devices 1, 2, 3, 4 or 5 of the above-described embodiments and their modifications on the back surface (surface on the side touching the human body) of a watch case 61. ing. A belt 62 is attached to the housing 61. At this time, the arrangement direction of the three light receiving elements 12, 13, and 14, the arrangement direction of the three light emitting elements 21, 22, and 23, and the extending direction of the line sensor 31 (for example, a direction parallel to the line segment LN in the figure) ) Is preferably parallel or substantially parallel to the extending direction of the arm. In this case, when the arm is moved, a large change in the degree of contact between the pulse wave measuring devices 1, 2, 3, 4, 5 and the arm is suppressed. As a result, more accurate noise removal can be performed.

  Moreover, since the electronic device 6 is provided with the pulse wave measuring devices 1, 2, 3, 4, and 5 according to the above-described embodiments and modifications thereof, the biological information 15B from which noise has been removed with higher accuracy. Can be used.

  In addition, the effect described in this specification is an illustration to the last. The effects of the present disclosure are not limited to the effects described in this specification. The present disclosure may have effects other than those described in this specification.

For example, this indication can take the following composition.
(1)
A light emitting element disposed on the wiring substrate and emitting light to the subject;
Three or more light receiving elements that receive light from the subject, disposed in at least three different distances from the light emitting elements in a predetermined direction from the light emitting elements on the wiring board;
The first detection signal detected by the first light receiving element relatively closer to the light emitting element among the three or more light receiving elements, and the first detection signal relatively separated from the light emitting element among the three or more light receiving elements. A second detection signal detected by two light receiving elements, and a third detection signal detected by a third light receiving element between the first light receiving element and the second light receiving element among the three or more light receiving elements. The fourth detection signal in which the influence of the noise component is reduced is derived by the calculation based on the above, and then the biological information of the subject having a correlation with the fourth detection signal is derived based on the fourth detection signal. A biological information measuring device comprising: a signal processing unit.
(2)
The biological signal according to (1), wherein the signal processing unit derives the fourth detection signal by subtracting the noise component from the third detection signal based on the first detection signal and the second detection signal. Information measuring device.
(3)
The biological information measuring device according to (1), wherein the biological information is information related to a pulse of the subject.
(4)
Each of the light receiving elements is a photodiode. (1) The biological information measuring device according to any one of (3).
(5)
Each of the first light receiving element, the second light receiving element, and the third light receiving element is constituted by a part of the light receiving parts in a common line sensor constituted by a plurality of light receiving parts arranged in a line. The biological information measuring device according to any one of 1) to (3).
(6)
The signal processing unit is a first light receiving unit corresponding to a signal peak value in a detection signal for one line obtained by the line sensor among the plurality of light receiving units included in the line sensor, or the first The biological information measuring device according to (5), wherein a plurality of the light receiving units including a light receiving unit are assigned as the second light receiving elements.
(7)
Each of the first light receiving element, the second light receiving element, and the third light receiving element is constituted by a part of the light receiving parts in a common image sensor constituted by a plurality of light receiving parts arranged in a matrix. (5) The biological information measuring device according to any one of (3).
(8)
The signal processing unit includes: a first light receiving unit corresponding to a signal peak value in a detection signal for one sheet obtained by the image sensor among the plurality of light receiving units included in the image sensor; The biological information measuring device according to (7), wherein a plurality of the light receiving units including a light receiving unit are assigned as the second light receiving elements.
(9)
A light receiving element disposed on the wiring board for receiving light from the subject;
Three or more light-emitting elements that emit light to a subject and are arranged at at least three different distances from the light-receiving element in a predetermined direction from the light-receiving element on the wiring board;
Each of the light emitting elements is caused to emit light sequentially, and a first detection signal detected by the light receiving element when the first light emitting element relatively closer to the light receiving element among the three or more light emitting elements emits light; A second detection signal detected by the light receiving element when the second light emitting element relatively distant from the light receiving element among the three or more light emitting elements emits light, and the three or more light emitting elements Of the noise component by calculation based on the third detection signal detected by the light receiving element when the third light emitting element between the first light emitting element and the second light emitting element emits light. A signal processing unit for deriving the biological information of the subject having a correlation with the fourth detection signal based on the fourth detection signal after deriving the fourth detection signal with reduced apparatus.
(10)
The biological signal according to (9), wherein the signal processing unit derives the fourth detection signal by subtracting the noise component from the third detection signal based on the first detection signal and the second detection signal. Information measuring device.
(11)
The biological information measuring device according to (10), wherein the biological information is information related to a pulse of the subject.
(12)
A light receiving element disposed on the wiring board for receiving light from the subject;
On the wiring board, in a predetermined direction from the light receiving element, the distance from the light receiving element is arranged at at least three places that are equal to each other or substantially equal to each other. Three or more light emitting elements that emit light to the light;
A first detection signal detected by the light receiving element when the first light emitting element having a relatively short emission wavelength among the three or more light emitting elements emits light; The second detection signal detected by the light receiving element when the second light emitting element having a relatively long emission wavelength is emitting light among the three or more light emitting elements, and the third detection signal among the three or more light emitting elements. By calculation based on a third detection signal detected by the light receiving element when a third light emitting element having an emission wavelength between the emission wavelength of the first light emitting element and the emission wavelength of the second light emitting element emits light. A signal processing unit that derives the biological information of the subject having a correlation with the fourth detection signal based on the fourth detection signal after deriving the fourth detection signal in which the influence of the noise component is reduced. Biological information measuring device provided.
(13)
The biological signal according to (12), wherein the signal processing unit derives the fourth detection signal by subtracting the noise component from the third detection signal based on the first detection signal and the second detection signal. Information measuring device.
(14)
The biological information measuring device according to (12), wherein the biological information is information related to a pulse of the subject.
(15)
Equipped with a biological information measuring device,
The biological information measuring device is
A light emitting element disposed on the wiring substrate and emitting light to the subject;
Three or more light receiving elements that receive light from the subject, disposed in at least three different distances from the light emitting elements in a predetermined direction from the light emitting elements on the wiring board;
The first detection signal detected by the first light receiving element relatively closer to the light emitting element among the three or more light receiving elements, and the first detection signal relatively separated from the light emitting element among the three or more light receiving elements. A second detection signal detected by two light receiving elements, and a third detection signal detected by a third light receiving element between the first light receiving element and the second light receiving element among the three or more light receiving elements. The fourth detection signal in which the influence of the noise component is reduced is derived by the calculation based on the above, and then the biological information of the subject having a correlation with the fourth detection signal is derived based on the fourth detection signal. An electronic device having a signal processing unit.
(16)
Equipped with a biological information measuring device,
The biological information measuring device is
A light receiving element disposed on the wiring board for receiving light from the subject;
Three or more light-emitting elements that emit light to a subject and are arranged at at least three different distances from the light-receiving element in a predetermined direction from the light-receiving element on the wiring board;
Each of the light emitting elements is caused to emit light sequentially, and a first detection signal detected by the light receiving element when the first light emitting element relatively closer to the light receiving element among the three or more light emitting elements emits light; A second detection signal detected by the light receiving element when the second light emitting element relatively distant from the light receiving element among the three or more light emitting elements emits light, and the three or more light emitting elements Of the noise component by calculation based on the third detection signal detected by the light receiving element when the third light emitting element between the first light emitting element and the second light emitting element emits light. An electronic apparatus comprising: a signal processing unit that derives the biological information of the subject having a correlation with the fourth detection signal based on the fourth detection signal after deriving the fourth detection signal with reduced noise.
(17)
Equipped with a biological information measuring device,
The biological information measuring device is
A light receiving element disposed on the wiring board for receiving light from the subject;
On the wiring board, in a predetermined direction from the light receiving element, the distance from the light receiving element is arranged at at least three places that are equal to each other or substantially equal to each other. Three or more light emitting elements that emit light to the light;
A first detection signal detected by the light receiving element when the first light emitting element having a relatively short emission wavelength among the three or more light emitting elements emits light; The second detection signal detected by the light receiving element when the second light emitting element having a relatively long emission wavelength is emitting light among the three or more light emitting elements, and the third detection signal among the three or more light emitting elements. By calculation based on a third detection signal detected by the light receiving element when a third light emitting element having an emission wavelength between the emission wavelength of the first light emitting element and the emission wavelength of the second light emitting element emits light. A signal processing unit that derives the biological information of the subject having a correlation with the fourth detection signal based on the fourth detection signal after deriving the fourth detection signal in which the influence of the noise component is reduced. Having electronic equipment.

  DESCRIPTION OF SYMBOLS 1, 2, 3, 4, 5 ... Biological information measuring device, 6 ... Electronic equipment, 10 ... Wiring board, 11 ... Light emitting element, 12, 13, 14 ... Light receiving element, 15 ... Signal processing circuit, 16 ... Memory | storage part, 16A ... Processing program, 16B ... Coefficient, 17 ... Communication part, 18 ... Display part, 19 ... Belt, 20 ... Housing, 21, 22, 23 ... Light emitting element, 24 ... Light receiving element, 31 ... Line sensor, 31A, 31B , 31C, 41A, 41B, 41C ... light receiving part, 41 ... image sensor, 51, 52, 53 ... light emitting element, 54 ... light receiving element, 61 ... housing, 62 ... belt, 100 ... subject, LN ... line segment.

Claims (17)

A light emitting element disposed on the wiring substrate and emitting light to the subject;
Three or more light receiving elements that receive light from the subject, disposed in at least three different distances from the light emitting elements in a predetermined direction from the light emitting elements on the wiring board;
The first detection signal detected by the first light receiving element relatively closer to the light emitting element among the three or more light receiving elements, and the first detection signal relatively separated from the light emitting element among the three or more light receiving elements. A second detection signal detected by two light receiving elements, and a third detection signal detected by a third light receiving element between the first light receiving element and the second light receiving element among the three or more light receiving elements. The fourth detection signal in which the influence of the noise component is reduced is derived by the calculation based on the above, and then the biological information of the subject having a correlation with the fourth detection signal is derived based on the fourth detection signal. A biological information measuring device comprising: a signal processing unit. The living body according to claim 1, wherein the signal processing unit derives the fourth detection signal by subtracting the noise component from the third detection signal based on the first detection signal and the second detection signal. Information measuring device. The biological information measuring device according to claim 1, wherein the biological information is information related to a pulse of the subject. The biological information measuring device according to claim 1, wherein each of the light receiving elements is a photodiode. The first light receiving element, the second light receiving element, and the third light receiving element are each configured by a part of the light receiving units in a common line sensor configured by a plurality of light receiving units arranged in a line. Item 2. The biological information measuring device according to Item 1. The signal processing unit is a first light receiving unit corresponding to a signal peak value in a detection signal for one line obtained by the line sensor among the plurality of light receiving units included in the line sensor, or the first The biological information measuring device according to claim 5, wherein a plurality of the light receiving units including a light receiving unit are allocated as the second light receiving elements. Each of the first light receiving element, the second light receiving element, and the third light receiving element is constituted by a part of the light receiving parts in a common image sensor constituted by a plurality of light receiving parts arranged in a matrix. The biological information measuring device according to claim 1. The signal processing unit includes: a first light receiving unit corresponding to a signal peak value in a detection signal for one sheet obtained by the image sensor among the plurality of light receiving units included in the image sensor; The biological information measuring device according to claim 7, wherein a plurality of the light receiving units including a light receiving unit are allocated as the second light receiving elements. A light receiving element disposed on the wiring board for receiving light from the subject;
Three or more light-emitting elements that emit light to a subject and are arranged at at least three different distances from the light-receiving element in a predetermined direction from the light-receiving element on the wiring board;
Each of the light emitting elements is caused to emit light sequentially, and a first detection signal detected by the light receiving element when the first light emitting element relatively closer to the light receiving element among the three or more light emitting elements emits light; A second detection signal detected by the light receiving element when the second light emitting element relatively distant from the light receiving element among the three or more light emitting elements emits light, and the three or more light emitting elements Of the noise component by calculation based on the third detection signal detected by the light receiving element when the third light emitting element between the first light emitting element and the second light emitting element emits light. A signal processing unit for deriving the biological information of the subject having a correlation with the fourth detection signal based on the fourth detection signal after deriving the fourth detection signal with reduced apparatus. The biological signal according to claim 9, wherein the signal processing unit derives the fourth detection signal by subtracting the noise component from the third detection signal based on the first detection signal and the second detection signal. Information measuring device. The biological information measuring device according to claim 10, wherein the biological information is information related to a pulse of the subject. A light receiving element disposed on the wiring board for receiving light from the subject;
On the wiring board, in a predetermined direction from the light receiving element, the distance from the light receiving element is arranged at at least three places that are equal to each other or substantially equal to each other. Three or more light emitting elements that emit light to the light;
A first detection signal detected by the light receiving element when the first light emitting element having a relatively short emission wavelength among the three or more light emitting elements emits light; The second detection signal detected by the light receiving element when the second light emitting element having a relatively long emission wavelength is emitting light among the three or more light emitting elements, and the third detection signal among the three or more light emitting elements. By calculation based on a third detection signal detected by the light receiving element when a third light emitting element having an emission wavelength between the emission wavelength of the first light emitting element and the emission wavelength of the second light emitting element emits light. A signal processing unit that derives the biological information of the subject having a correlation with the fourth detection signal based on the fourth detection signal after deriving the fourth detection signal in which the influence of the noise component is reduced. Biological information measuring device provided. The living body according to claim 12, wherein the signal processing unit derives the fourth detection signal by subtracting the noise component from the third detection signal based on the first detection signal and the second detection signal. Information measuring device. The biological information measuring device according to claim 12, wherein the biological information is information related to a pulse of the subject. Equipped with a biological information measuring device,
The biological information measuring device is
A light emitting element disposed on the wiring substrate and emitting light to the subject;
Three or more light receiving elements that receive light from the subject, disposed in at least three different distances from the light emitting elements in a predetermined direction from the light emitting elements on the wiring board;
The first detection signal detected by the first light receiving element relatively closer to the light emitting element among the three or more light receiving elements, and the first detection signal relatively separated from the light emitting element among the three or more light receiving elements. A second detection signal detected by two light receiving elements, and a third detection signal detected by a third light receiving element between the first light receiving element and the second light receiving element among the three or more light receiving elements. The fourth detection signal in which the influence of the noise component is reduced is derived by the calculation based on the above, and then the biological information of the subject having a correlation with the fourth detection signal is derived based on the fourth detection signal. An electronic device having a signal processing unit. Equipped with a biological information measuring device,
The biological information measuring device is
A light receiving element disposed on the wiring board for receiving light from the subject;
Three or more light-emitting elements that emit light to a subject and are arranged at at least three different distances from the light-receiving element in a predetermined direction from the light-receiving element on the wiring board;
Each of the light emitting elements is caused to emit light sequentially, and a first detection signal detected by the light receiving element when the first light emitting element relatively closer to the light receiving element among the three or more light emitting elements emits light; A second detection signal detected by the light receiving element when the second light emitting element relatively distant from the light receiving element among the three or more light emitting elements emits light, and the three or more light emitting elements Of the noise component by calculation based on the third detection signal detected by the light receiving element when the third light emitting element between the first light emitting element and the second light emitting element emits light. An electronic apparatus comprising: a signal processing unit that derives the biological information of the subject having a correlation with the fourth detection signal based on the fourth detection signal after deriving the fourth detection signal with reduced noise. Equipped with a biological information measuring device,
The biological information measuring device is
A light receiving element disposed on the wiring board for receiving light from the subject;
On the wiring board, in a predetermined direction from the light receiving element, the distance from the light receiving element is arranged at at least three places that are equal to each other or substantially equal to each other. Three or more light emitting elements that emit light to the light;
A first detection signal detected by the light receiving element when the first light emitting element having a relatively short emission wavelength among the three or more light emitting elements emits light; The second detection signal detected by the light receiving element when the second light emitting element having a relatively long emission wavelength is emitting light among the three or more light emitting elements, and the third detection signal among the three or more light emitting elements. By calculation based on a third detection signal detected by the light receiving element when a third light emitting element having an emission wavelength between the emission wavelength of the first light emitting element and the emission wavelength of the second light emitting element emits light. A signal processing unit that derives the biological information of the subject having a correlation with the fourth detection signal based on the fourth detection signal after deriving the fourth detection signal in which the influence of the noise component is reduced. Having electronic equipment.

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