Biological information measuring device and biological information measuring program

Abstract

To provide a biological information measurement device for measuring correctly, a pulse wave.SOLUTION: A light emission part (G light emission part 14g or R light emission part 14r) radiates light to a prescribed part on a measured person. A light reception part (G light reception part 15g or R light reception part 15r) receives light which passes through a prescribed part, or is reflected on the prescribed part. A pulse wave acquiring part 111 acquires a pulse wave of the measured person on the basis of the light received by the light reception part. A light emission control part 112 performs control so as to change a wavelength of light emitted from the light emission part, on the basis of position determination information which indicates whether the measured person is at outdoor, or at indoor, and a detection result of whether the measured person is in an exercising state, and according to brightness in the surrounding of the measured person, the light emission control part performs control so as to change a light amount of the light emitted from the light emission part.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a biological information measuring device and a biological information measuring program. [Background technology]

[0002] In recent years, smartwatches that function as biological information measuring devices employing technology for measuring pulse waves, such as that described in Patent Document 1, have become popular. To avoid the effects of ambient light outdoors, this type of smartwatch illuminates the wrist of the wearer of the smartwatch (the person being measured) with green light when measuring pulse waves. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-116210 Summary of the Invention [Problem to be solved by the invention]

[0004] Patent Document 1 describes that when the subject's body movements are large, both the green and red light-emitting elements are turned on, and when the body movements are small, the green light-emitting element is turned off and only the red light-emitting element is turned on. To measure pulse waves more accurately, it is not enough to simply select light-emitting elements according to the magnitude of body movements. Therefore, there is a demand for a biological information measurement device and a biological information measurement program that can measure pulse waves more accurately.

[0005] An object of the present invention is to provide a biological information measurement device and a biological information measurement program that can measure pulse waves more accurately. [Means for solving the problem]

[0006] The present invention provides a biological information measuring device comprising: a position discrimination information acquisition unit that acquires position discrimination information indicating whether a person being measured is located outdoors or indoors; an exercise state detection unit that detects whether the person being measured is in an exercise state; a brightness detection unit that detects the brightness around the person being measured; a light emitting unit that irradiates light onto a predetermined location on the person being measured; a light receiving unit that receives light that is reflected at or transmitted through the predetermined location; a pulse wave acquisition unit that acquires the pulse wave of the person being measured based on the light received by the light receiving unit; and a light emission control unit that controls the light emitting unit to change the wavelength of the light emitted based on the position discrimination information acquired by the position discrimination information acquisition unit and the detection result detected by the exercise state detection unit that indicates whether the person being measured is in an exercise state, and controls the light emitting unit to change the amount of light emitted in accordance with the brightness around the person being measured detected by the brightness detection unit.

[0007] The present invention provides a biometric information measurement program that causes a computer to execute the following steps: acquiring position determination information indicating whether the person being measured is located outdoors or indoors; detecting whether the person being measured is in an exercising state; acquiring a value indicating the brightness of the person being measured's surroundings; controlling a light-emitting unit to irradiate light at a predetermined location on the person being measured; acquiring a received signal generated by a light-receiving unit receiving light that is reflected at or transmitted through the predetermined location; acquiring the pulse wave of the person being measured based on the received signal; and controlling the light-emitting unit to change the wavelength of the light emitted based on the position determination information and the detection result indicating whether the person being measured is in an exercising state, and controlling the light-emitting unit to change the amount of light emitted in accordance with the value indicating the brightness of the person being measured. [Effects of the Invention]

[0008] According to the biological information measurement device and the biological information measurement program of the present invention, pulse waves can be measured more accurately. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a block diagram showing a biological information measuring device according to an embodiment; [Figure 2] FIG. 2 is a characteristic diagram showing the relationship between wavelength and light absorption intensity. [Figure 3] FIG. 10 is a partial block diagram showing a modified example of the biological information measuring device according to the embodiment. [Figure 4] 1 is a flowchart illustrating a process executed by a biological information measurement device according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] A biological information measurement device and a biological information measurement program according to an embodiment will be described below with reference to the accompanying drawings. In FIG. 1, a biological information measurement device 10 and a smartphone 20 communicate with each other via short-range wireless communication such as Bluetooth (registered trademark). Typically, the biological information measurement device 10 is configured as a wristwatch. The biological information measurement device 10 may also be a so-called smartwatch. However, FIG. 1 does not illustrate the configuration of the watch. The biological information measurement device 10 is not limited to a wristwatch type, and may also be configured as a ring type or a type worn on the tip of a finger. Note that if the biological information measurement device 10 is configured as a ring type or worn on the tip of a finger, it becomes easier to measure pulse waves than if it is configured as a wristwatch type.

[0011] The biological information measuring device 10 includes a calculation unit 11, a ROM (Read Only Memory) 12, a RAM (Random Access Memory) 13, a G light-emitting unit 14g, an R light-emitting unit 14r, a G light-receiving unit 15g, an R light-receiving unit 15r, a short-range wireless communication unit 16, a motion sensor 17, a brightness sensor 18, and a display unit 19. The smartphone 20 includes a GNSS receiving unit 21, a signal strength detection unit 22, a short-range wireless communication unit 23, a data acquisition unit 24, a data processing unit 25, and a display unit 26. The signal strength detection unit 22, the data acquisition unit 24, and the data processing unit 25 may be configured by a central processing unit (CPU) of the smartphone 20.

[0012] The GNSS receiver 21 of the smartphone 20 receives radio waves from satellites for the Global Navigation Satellite System (GNSS). An example of the GNSS is the Global Positioning System (GPS). The signal strength detector 22 detects the signal strength of the GNSS signal received by the GNSS receiver 21, generates determination information indicating whether the signal strength is equal to or greater than a threshold, and supplies the determination information to the short-range wireless communication unit 23.

[0013] If the signal strength of the GNSS signal is equal to or greater than a threshold, it is considered that the subject carrying the biological information measuring device 10 and smartphone 20 is located outdoors, and if the signal strength is less than the threshold, it is considered that the subject is located indoors. Therefore, the discrimination information generated by the signal strength detection unit 22 is position discrimination information that indicates whether the subject is located outdoors or indoors. The short-range wireless communication unit 23 transmits the position discrimination information to the short-range wireless communication unit 16.

[0014] Instead of determining whether the person being measured is located outdoors or indoors using the GNSS receiver 21 and the signal strength detector 22, the position of the person being measured may be determined based on a wireless LAN (Wi-Fi) access point. Furthermore, whether the person being measured is located indoors may be determined using geomagnetic positioning based on the magnetic force emitted by iron materials such as steel frames or rebars used to support buildings or underground spaces. The method for determining whether the person being measured is located outdoors or indoors is arbitrary.

[0015] The components of the biological information measuring device 10 will be described. The calculation unit 11 can be configured with a CPU of a microcomputer. The calculation unit 11 has, as its functional components, a pulse wave acquisition unit 111 and a light emission control unit 112. The ROM 12 stores a computer program (biological information measurement program) that causes the calculation unit 11 to acquire a pulse wave and control light emission by the G light-emitting unit 14g and the R light-emitting unit 14r. The calculation unit 11 executes the computer program stored in the ROM 12 while using the RAM 13 as a working memory. The calculation unit 11 executes the computer program, thereby functionally configuring the pulse wave acquisition unit 111 and the light-emission control unit 112.

[0016] The G light-emitting unit 14g may be configured with a light-emitting diode (hereinafter referred to as an LED) that emits green light (hereinafter referred to as G light). The G light is, for example, light having a wavelength of 500 nm to 600 nm. The R light-emitting unit 14r may be configured with an LED that emits red light (hereinafter referred to as R light). The R light is, for example, light having a wavelength of 640 nm to 780 nm. As will be described later, the G light-emitting unit 14g and the R light-emitting unit 14r selectively irradiate a predetermined location on the subject with the G light and the R light. The predetermined location (hereinafter referred to as the light-irradiated location) is, for example, the surface of the wrist on the back side of the hand.

[0017] The reason for using G light or R light as the light for measuring pulse waves is as follows. Figure 2 shows the relationship between wavelength and absorption strength when light is irradiated onto hemoglobin and water. The solid line shows the absorption strength in hemoglobin, and the dashed line shows the absorption strength in water. The absorption strength in hemoglobin and water is small around wavelengths of 600 nm to 1500 nm, which is called the optical window. The G light wavelength of 500 nm to 600 nm is close to the optical window, and the R light wavelength of 640 nm to 780 nm is within the optical window. Therefore, it is preferable to use G light or R light.

[0018] The G light-receiving unit 15g and the R light-receiving unit 15r are provided on the same side of the light-irradiated area as the G light-emitting unit 14g and the R light-emitting unit 14r. The G light-receiving unit 15g receives light reflected from the light-irradiated area when the G light-emitting unit 14g emits G light. The R light-receiving unit 15r receives light reflected from the light-irradiated area when the R light-emitting unit 14r emits R light. The G light-receiving unit 15g and the R light-receiving unit 15r may be provided on the opposite side of the light-irradiated area from the G light-emitting unit 14g and the R light-emitting unit 14r, and may receive G light or R light that has passed through a part of the subject's body.

[0019] The short-range wireless communication unit 16 receives the position determination information transmitted from the short-range wireless communication unit 23. The short-range wireless communication unit 16 functions as a position determination information acquisition unit that acquires the position determination information. The biological information measurement device 10 may be provided with a GNSS receiving unit and a signal strength detection unit similar to the GNSS receiving unit 21 and the signal strength detection unit 22. When the biological information measurement device 10 is provided with a GNSS receiving unit and a signal strength detection unit, the GNSS receiving unit and the signal strength detection unit function as the position determination information acquisition unit. The short-range wireless communication unit 16 may receive the GNSS signal received by the GNSS receiving unit 21, and a signal strength detection unit provided in the biological information measurement device 10 may detect the signal strength of the GNSS signal.

[0020] The motion sensor 17 detects the motion of the person being measured. The motion sensor 17 includes at least an acceleration sensor and detects the acceleration when the person being measured moves. The motion sensor 17 may include a gyro sensor in addition to the acceleration sensor to detect the posture of the person being measured. The calculation unit 11 detects whether the person being measured is in an exercising state based on whether the motion detection value by the motion sensor 17 is equal to or greater than a threshold value. The motion sensor 17 and the calculation unit 11 function as an exercise state detection unit that detects whether the person being measured is in an exercising state.

[0021] If the detected value is equal to or greater than the threshold, the calculation unit 11 determines that the subject is in an exercise state, i.e., exercising, and if the detected value is less than the threshold, the calculation unit 11 determines that the subject is in a non-exercise state, i.e., not exercising. Note that the exercise state in which the subject is exercising means that the subject's arms, etc. are moving. The non-exercise state means that the subject is in a resting state, not moving much.

[0022] The brightness sensor 18 detects the brightness around the subject. For example, the brightness sensor 18 can be configured with a cadmium sulfide cell. The brightness detection value by the brightness sensor 18 is supplied to the calculation unit 11. The brightness around the subject may be expressed in terms of illuminance or luminance.

[0023] The pulse wave acquiring unit 111 acquires the pulse wave of the subject based on a received signal generated by the G light receiving unit 15g or the R light receiving unit 15r when it receives reflected light from the illuminated area. If the received signal is a voltage value corresponding to the intensity of the reflected light, the calculation unit 11 converts the voltage value into a digital value, and the pulse wave acquiring unit 111 acquires the pulse wave of the subject based on the digital value indicating the intensity of the reflected light.

[0024] Display unit 19 may display the pulse wave acquired by pulse wave acquisition unit 111. Calculation unit 11 may calculate the heart rate based on the acquired pulse wave, and display unit 19 may display the heart rate. Display unit 19 may be a liquid crystal panel or an organic EL panel. When the motion detection value by motion sensor 17 is greater than or equal to a threshold value and it can be determined that the subject is moving vigorously, calculation unit 11 may control display unit 19 to display text or an image indicating that it is not suitable to acquire a pulse wave.

[0025] The calculation unit 11 may calculate a stress index based on the pulse wave, and the display unit 19 may display the stress index. Note that the power spectrum density may be calculated from the pulse wave, and the stress index may be determined by dividing the low-frequency component (power spectrum of 0.04 Hz to 0.15 Hz) by the high-frequency component (power spectrum of 0.15 Hz to 0.4 Hz). The low-frequency component represents both sympathetic and parasympathetic nervous activity, and the high-frequency component represents parasympathetic nervous activity.

[0026] The light-emission control unit 112 controls the emission of G light from the G light-emitting unit 14g and the emission of R light from the R light-emitting unit 14r. When the light-emission control unit 112 controls one of the G light-emitting unit 14g and the R light-emitting unit 14r to an emitting state, the light-emission control unit 112 controls the other to a non-emitting state. The light-emission control unit 112 controls the amount of light emitted by the G light and the R light.

[0027] Short-range wireless communication unit 16 may transmit data indicating the pulse wave acquired by pulse wave acquisition unit 111 (pulse wave data) to short-range wireless communication unit 23. Data acquisition unit 24 may acquire the pulse wave data received by short-range wireless communication unit 23, and data processing unit 25 may process the pulse wave data. Display unit 26 may display a waveform obtained by processing the pulse wave data. Data processing unit 25 may calculate a heart rate or a stress index based on the pulse wave data, and display unit 26 may display the heart rate or the stress index. Display unit 26 may be a liquid crystal panel or an organic EL panel. It is optional whether smartphone 20 acquires pulse wave data and how to use the pulse wave data when it has been acquired.

[0028] The short-range wireless communication unit 16 may transmit a motion detection value obtained by the motion sensor 17 to the short-range wireless communication unit 23. The data acquisition unit 24 acquires the motion detection value received by the short-range wireless communication unit 23. When the motion detection value is greater than or equal to a threshold value and it can be determined that the subject is moving vigorously, the data processing unit 25 may control the display unit 26 to display a character or image indicating that it is not suitable for acquiring a pulse wave.

[0029] 3, instead of providing a G light-emitting unit 14g and an R light-emitting unit 14r, an RGB light-emitting unit 14 including LEDs of each color that emit R light, G light, and blue light (hereinafter referred to as B light) may be used. Instead of providing a G light-receiving unit 15g and an R light-receiving unit 15r, a light-receiving unit 15 that receives reflected light from the illuminated area when the RGB light-emitting unit 14 emits light may be used.

[0030] 3 is used, the light emission control unit 112 controls the wavelength (i.e., the color of the light) of the light emitted by the RGB light emission unit 14. The light emission control unit 112 controls the RGB light emission unit 14 to emit G light, or controls the RGB light emission unit 14 to emit R light. The light emission control unit 112 may adjust the wavelength of the light emitted within the wavelength range of the G light, or may adjust the wavelength of the light emitted within the wavelength range of the R light.

[0031] Using the flowchart shown in Fig. 4, we will explain how the calculation unit 11 controls the biological information measuring device 10. The flowchart shown in Fig. 4 shows control when the biological information measuring device 10 is configured as shown in Fig. 1. The flowchart shown in Fig. 4 also shows processing that a biological information measuring program causes a computer to execute.

[0032] 4, when the biological information measuring device 10 is powered on and processing starts, the calculation unit 11 determines in step S1 whether the subject is located outdoors based on the position determination information. If the subject is located outdoors (YES), the calculation unit 11 (light-emission control unit 112) controls the G light-emitting unit 14g to emit G light in step S3, and proceeds to step S5. Step S1 corresponds to a step executed by the biological information measuring program on a computer to acquire position determination information indicating whether the subject is located outdoors or indoors.

[0033] If the person being measured is not outdoors in step S1 (NO), the calculation unit 11 determines in step S2 whether the person being measured is exercising. If the person being measured is exercising (YES), the calculation unit 11 (light-emission control unit 112) controls the G light-emitting unit 14g to emit G light in step S3, and moves the process to step S5. At this time, the light-emission control unit 112 controls the G light-emitting unit 14g to emit G light at a reference light intensity. Step S2 corresponds to a step that the biological information measurement program causes the computer to execute, detecting whether the person being measured is exercising.

[0034] If the subject is not in an exercising state in step S2 (NO), the calculation unit 11 (light-emission control unit 112) controls the R light-emitting unit 14r to emit R light in step S4, and moves the process to step S5. At this time, the light-emission control unit 112 controls the R light-emitting unit 14r to emit R light at a reference light intensity.

[0035] Steps S3 and S4 correspond to the steps executed by the computer by the biological information measurement program, which control the light emitting unit to irradiate a predetermined location of the subject with light. Also, steps S3 and S4 correspond to the steps executed by the computer by the biological information measurement program, which control the light emitting unit to change the wavelength of light emitted based on the position determination information and the detection result indicating whether the subject is in an exercising state.

[0036] In step S5, the calculation unit 11 determines whether the brightness around the subject is equal to or greater than a predetermined brightness. If the brightness around the subject is equal to or greater than the predetermined brightness (YES), in step S6, the calculation unit 11 (light-emission control unit 112) controls the amount of light emitted by the G light-emitting unit 14g or the R light-emitting unit 14r to be increased above the reference light amount, and the process proceeds to step S8. Step S5 corresponds to a step that the biological information measurement program causes the computer to execute, to acquire a value indicating the brightness around the subject.

[0037] If the ambient brightness is equal to or greater than a predetermined level, the pulse wave can be measured more accurately by increasing the amount of light emitted by the G light-emitting element 14g or the R light-emitting element 14r above the standard amount of light.

[0038] If the ambient brightness is not equal to or greater than the predetermined brightness in step S5 (NO), the calculation unit 11 (light-emission control unit 112) sets the amount of light emitted by the G light-emitting unit 14g or the R light-emitting unit 14r to the reference light amount in step S7, and proceeds to step S8. The light-emission control unit 112 maintains the reference light amount if the light is already being emitted at the reference light amount, and returns the light amount to the reference light amount if the light amount has increased above the reference light amount. Steps S6 and S7 correspond to steps executed by the biological information measurement program in which the computer controls the light-emitting unit to change the amount of light emitted in accordance with a value indicating the brightness of the subject's surroundings.

[0039] The light-emission control unit 112 may control the amount of light emitted by the G light-emitting unit 14g or the R light-emitting unit 14r in three or more stages depending on the ambient brightness. The light-emission control unit 112 may continuously increase the amount of light emitted by the G light-emitting unit 14g or the R light-emitting unit 14r as the ambient brightness increases.

[0040] In step S8, the calculation unit 11 (pulse wave acquisition unit 111) acquires the pulse wave of the subject based on the received signal from the G light-receiving unit 15g or the R light-receiving unit 15r, and then proceeds to step S9. Step S8 corresponds to a step of acquiring a received signal generated by the light-receiving unit receiving light reflected at or transmitted through a predetermined location, and a step of acquiring the pulse wave of the subject based on the received signal, which are executed by the biological information measurement program in the computer.

[0041] In step S9, the calculation unit 11 determines whether or not a power-off operation has been performed. If a power-off operation has not been performed (NO), the calculation unit 11 returns the process to step S1 and repeats the processes from step S1 onwards. If a power-off operation has been performed (YES), the calculation unit 11 turns off the power in step S10 and ends the process.

[0042] As described above, the biological information measuring device 10 changes the wavelength of light emitted by the light-emitting unit (G light-emitting unit 14g, R light-emitting unit 14r, or RGB light-emitting unit 14) based on the position determination information and the detection result indicating whether the subject is in an exercising state. The biological information measuring device 10 also changes the amount of light emitted by the light-emitting unit depending on the brightness around the subject. Therefore, the biological information measuring device 10 can measure the pulse wave more accurately.

[0043] Specifically, the light-emission control unit 112 preferably controls the light-emitting unit to emit green light when the person being measured is outdoors, the light-emission control unit 112 preferably controls the light-emitting unit to emit green light when the person being measured is exercising, and the light-emission control unit 112 preferably controls the light-emitting unit to emit red light when the person being measured is indoors and not exercising.

[0044] The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the gist of the present invention. [Explanation of symbols]

[0045] 10 Biological information measuring device 11 Arithmetic section 12 ROM 13 RAM 14g G light-emitting part 14r R light emitting part 15g G receiver 15r R receiver 16 Near Field Wireless Communication Department 17 Motion Sensor 18 Brightness sensor 19 Display section

Claims

1. Obtain location discrimination information indicating whether the subject is located outdoors or indoors a position determination information acquisition unit; an exercise state detection unit that detects whether the subject is in an exercise state; a brightness detection unit that detects the brightness around the subject; a light emitting unit that irradiates light onto a predetermined location of the subject; a light receiving unit that receives light reflected at the predetermined location or transmitted through the predetermined location; a pulse wave acquiring unit that acquires a pulse wave of the subject based on the light received by the light receiving unit; a light emission control unit that controls the light emitting unit to change the wavelength of light emitted to red when the position determination information acquired by the position determination information acquisition unit indicates that the subject is located indoors and the detection result detected by the exercise state detection unit, which indicates whether the subject is in an exercise state, indicates that the subject is in a non-exercise state, and that controls the light emitting unit to increase the amount of light emitted above a reference amount of light when the brightness around the subject detected by the brightness detection unit is equal to or greater than a predetermined brightness; A biological information measuring device comprising:

2. Acquire position determination information indicating whether the subject is located outdoors or indoors. a position determination information acquisition unit; an exercise state detection unit that detects whether the subject is in an exercise state; a brightness detection unit that detects the brightness around the subject; a light emitting unit that irradiates light onto a predetermined location of the subject; a light receiving unit that receives light reflected at the predetermined location or transmitted through the predetermined location; a pulse wave acquiring unit that acquires a pulse wave of the subject based on the light received by the light receiving unit; when the position determination information acquired by the position determination information acquisition unit indicates that the person being measured is located outdoors, controlling the light emitting unit to emit green light; when the detection result by the exercise state detection unit indicates that the subject is in an exercise state, controlling the light emitting unit to emit light in green; a light emission control unit that controls the light emitting unit to emit red light when the position determination information acquired by the position determination information acquisition unit indicates that the subject is located indoors and the detection result by the exercise state detection unit indicates that the subject is not exercising, and controls the light emitting unit to change the amount of light emitted in accordance with the brightness of the subject's surroundings detected by the brightness detection unit; A biological information measuring device comprising:

3. On the computer, Obtain location discrimination information indicating whether the subject is located outdoors or indoors Steps and detecting whether the subject is in an exercise state; acquiring a value indicating the brightness of the subject's surroundings; controlling a light emitting unit to irradiate light onto a predetermined location of the subject; acquiring a reception signal generated by a light receiving unit receiving light reflected at or transmitted through the predetermined location; acquiring a pulse wave of the subject based on the received signal; When the position determination information indicates that the subject is located indoors and the detection result indicating whether the subject is in an exercising state indicates that the subject is in a non-exerting state, controlling the light emitting unit to change the wavelength of the light emitted to red, and when a value indicating the brightness around the subject is equal to or greater than a predetermined value, controlling the light intensity of the light emitting unit to be increased above a reference light intensity; A biological information measurement program that executes the above.

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