WO2005092179A1

WO2005092179A1 - Biological information measuring instrument

Info

Publication number: WO2005092179A1
Application number: PCT/JP2005/002018
Authority: WO
Inventors: Kazuya Maegawa; Takashi Nakamura; Koichi Moriya; Shinichiro Miyahara
Original assignee: Seiko Instruments Inc.
Priority date: 2004-03-26
Filing date: 2005-02-10
Publication date: 2005-10-06
Also published as: JP4476664B2; JP2005270544A

Abstract

A biological information measuring instrument comprising a body, a biological sensor section provided in the body, irradiating an organism with light, and generating a biological information signal depending on the quantity of backscattering light from the organism, a section provided in the body and operating biological information based on the biological information signal, and a section arranged on the lower surface side of the body and detecting whether or not the biological sensor section touching the surface of the organism, characterized in that the detecting section comprises a light emitting section for irradiating the organism with light, a cover glass arranged on the lower surface of the organism, transmitting/reflecting the light emitted from the light emitting section, and transmitting backscattering light from the organism, a section for receiving the transmitted light from the cover glass, and a section for judging whether the organism is in contact with the biological sensor section or not based on a light reception signal received by the light receiving section.

Description

Specification

Biological information measurement device

Technical field

The present invention relates to a biological information measuring device capable of measuring biological information such as a pulse while being worn on a wrist (arm).

Priority is claimed on Japanese Patent Application No. 2004-091943 filed on March 26, 2004, the content of which is incorporated herein by reference.

Background art

[0002] In recent years, interest in health management has increased, and various types of biological information measuring devices that can measure various biological information such as a pulse while being worn on a wrist (arm) or the like have been provided. For example, see Patent Document 1).

[0003] The pulse meter (biological information measuring device) described in Patent Document 1 includes two electrodes on the skin contact side. When the two electrodes touch the skin, a minute current flows through the skin, and the voltage between the two electrodes decreases. Therefore, it is determined that the pulse sensor is in contact with the skin. Therefore, the presence or absence of contact with the skin can be detected based on the potential difference between the two electrodes.

[0004] A pulse measuring device (biological information measuring device) having a pulse measuring system using a light emitting diode (light emitting portion) and a light receiving element (light receiving portion) has also been proposed (for example, see Patent Document 2). . The pulse meter described in Patent Document 2 has a light receiving element for measuring light and darkness, and detects the presence or absence of a contact according to the output of the light receiving element.

Patent Document 1: Japanese Patent Application Laid-Open No. 2003-70757 (Paragraph No. 0021-0029, FIG. 2, etc.) Patent Document 2: Japanese Patent Application Laid-Open No. 60-246736

Disclosure of the invention

Problems to be solved by the invention

[0005] However, the biological information measuring device described in Patent Document 1 described above can accurately detect contact with a living body when the electrodes are large to some extent, but erroneous detection often occurs when the electrodes are small. For example, it is difficult to use with small terminals such as wristwatch type Problem. In addition, the biological information measurement device described in Patent Document 2 simply determines the brightness from the output from the light receiving element and determines the presence / absence of contact, and thus may erroneously detect depending on the degree of external light. .

[0006] The present invention has been made in view of the above circumstances, and provides a biological information measuring device that can be miniaturized with a simple configuration and that does not erroneously detect even when external light enters. The porpose is to do.

Means for solving the problem

[0007] The present invention provides the following means in order to solve the above problems.

[0008] A biological information measurement device of the present invention includes a main body, and a biological sensor provided on the main body and configured to irradiate light to a living body and generate a biological information signal according to the amount of backscattered light from the living body. A biometric information calculation unit provided on the main body and calculating biometric information based on the biometric information signal; and a force provided on the lower surface side of the main body, wherein the biometric sensor unit contacts the surface of the living body. A light emitting unit for irradiating the living body with light, and the detecting unit is disposed on a lower surface of the main body to transmit and reflect the light emitted by the light emitting unit. A cover glass for transmitting light scattered backward in the living body, a light receiving unit for receiving light transmitted through the cover glass, and a living body and the living body sensor based on a light receiving signal received by the light receiving unit. Characterized in that it comprises a determination section which parts and to determine whether mosquitoes ゝ not in contact.

In the biological information measuring device according to the present invention, the light emitting unit also irradiates light toward the living body. The irradiated light is received by the light receiving unit by reflection on the surface of the cover glass, propagation in the cover glass, backscattering in living organisms, and the like. The determination unit provided in the detection unit determines whether the surface of the living body and the living body sensor unit are based on the light reception signal received by the light receiving unit when the light emitting unit is emitting light and when the light emitting unit is not emitting light. Make contact or not to judge. The determining unit determines that the surface of the living body is in contact with the biological sensor unit, that is, determines that the main body is attached to the wrist (arm, etc.), and irradiates the living body with light toward the living body by the biological sensor unit. A biological information signal corresponding to the amount of backscattered light from the object. Further, the biological information detection unit performs a predetermined operation on the biological information signal to calculate biological information such as a pulse. Also, even if external light enters the light receiving unit, the surface of the living body and the This eliminates the possibility of erroneous detection of the contact of the user.

[0010] Further, in the biological information measuring device of the present invention, the light receiving section receives the backscattered light of the biological force transmitted through the cover glass and generates a biological information signal according to the amount of backscattered light. I prefer to.

In the biological information measuring device according to the present invention, the light receiving unit performs both the contact between the surface of the living body and the biological sensor unit based on the received light and the generation of the biological information signal. A small number of points can be obtained, and furthermore, the overall size of the biological information measuring device can be reduced.

[0012] In addition, the biological information measuring device of the present invention may be configured such that the cover glass has a reflecting surface disposed between the light emitting unit and the light receiving unit, and reflecting a part of light propagating in the cover glass. It is preferable to provide

[0013] In the biological information measurement device according to the present invention, of the light irradiated by the light irradiation unit, light that has propagated inside the cover glass is reflected toward the living body surface side by the reflection surface. For this reason, when measuring the biological information, it is possible to block the light propagating in the cover glass that does not contain the biological information, so that it is possible to measure the biological information with high accuracy.

[0014] Further, the biological information measuring device of the present invention preferably includes a bundle of optical fibers, one end of which is disposed in close proximity to the cover glass and the other end thereof is disposed in proximity to the light receiving surface of the light receiving section. .

[0015] In the biological information measuring device according to the present invention, since the optical fiber is provided, light that has passed through a surface portion such as a skin of a living body is reflected on the outer peripheral surface of the optical fiber. Light that has passed only through the surface such as the epidermis of a living body does not contain much biological information, so by blocking this light, it enters the optical fiber, propagates through the optical fiber, and is guided to the light receiving unit. Most of the light is light that has passed deep into the body below the dermis, that is, light that contains a lot of biological information.

[0016] Further, the biological information measuring device according to the present invention may be arranged such that a surface of the cover glass facing the light receiving unit is provided.

It is preferable that a light-collecting unit that collects backscattered light from the living body is provided on a surface of the cover glass that faces the light receiving unit. In the biological information measuring device according to the present invention, light radiated by the light emitting unit and scattered backward in the living body is efficiently collected on the light receiving surface of the light receiving unit by the light collecting unit. Therefore, when a biological information signal such as a pulse signal is generated, the area of the light receiving unit can be reduced, so that the overall size of the biological information measuring device can be reduced.

The invention's effect

According to the biological information measuring device of the present invention, the presence or absence of a contact is detected based on the light received by the light receiving unit when the light emitting state of the light emitting unit is changed. Thus, contact with a living body can be detected. Therefore, even when external light enters the light receiving unit, the contact with the living body can be accurately recognized, and the calculation of the biological information can be performed with high accuracy.

Brief Description of Drawings

FIG. 1 is a front view (top view) showing an embodiment of a biological information measuring device according to the present invention.

FIG. 2 is a rear view (bottom view) of the biological information measuring device shown in FIG. 1.

FIG. 3 is a side view showing a state where the biological information measuring device shown in FIG. 1 is mounted on a wrist.

FIG. 4 is a side view showing a state in which the biological information measuring device shown in FIG. 1 is mounted on a wrist, viewed from a direction opposite to the direction shown in FIG. 3.

5 is a sectional view of the biological information measuring device shown in FIG. 1.

6 is a sectional view taken along the line DD of the biological information measuring device shown in FIG. 1.

FIG. 7 is a sectional view showing a biological sensor unit of the biological information measuring device shown in FIG. 1.

8 is a flowchart showing contact detection performed in a data processing unit of the biological information measuring device shown in FIG. 5.

FIG. 9 is a cross-sectional view showing another modified example of the biological sensor unit of the biological information measuring device shown in FIG. 7.

FIG. 10 is a cross-sectional view showing another modified example of the biological sensor unit of the biological information measuring device shown in FIG. 7.

FIG. 11 is a cross-sectional view showing another modified example of the biological sensor unit of the biological information measuring device shown in FIG. 7. is there.

FIG. 12 is a plan view showing another modified example of the biological information measuring device shown in FIG. 1.

13 is a cross-sectional view showing a positional relationship between an LED and a PD of the biological information measuring device shown in FIG.

FIG. 14 is a graph showing a voltage value output by a PD according to a contact state between a living body sensor unit and a living body in an example of the present invention.

Explanation of symbols

[0020] B: body surface (living body), 1, 50 · · · biological information measurement device, 2 · housing (body), 2a- lower surface of the body, 4 · LED (light emitting part), 5 · 'PD (Light receiving part), 7… Data processing part (biological information detecting part), 7a… Determining part, 8… Biological sensor part, 23 ··· Cover glass, 23a · Reflective surface, 40… Optical fin, 40a… One end of optical fiber, 40b… The other end of optical fiber, 41… Concave part (condensing part)

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, an embodiment of the biological information measuring device according to the present invention will be described with reference to FIGS. 1 to 11.

As shown in FIGS. 1 to 8, a biological information measuring device 1 of the present embodiment is a wristwatch type and calculates a pulse rate, which is biological information, in a state of being worn on a wrist (arm) A. It is.

The biological information measuring device 1 includes a housing (main body) 2 containing various electric and electronic components, and a housing 2 with a lower surface 2a of the housing 2 facing the living body surface B side. (Wheel A), LED (Light Emitting Diode) 4 that is provided on the housing 2 and irradiates light to the living body surface (living body) B, and PD (Light emitting diode) that receives backscattered light from the living body Photo—Diode) A biometric sensor unit 6 having a sensor 5 and a pulse signal (biological information signal) provided in the housing 2 and corresponding to the amount of light received by the biosensor unit 6 are calculated, and the generated pulse signal is calculated. A data processing unit (biological information calculation unit) 7 for calculating the number.

The biological sensor unit 6 also functions as a detection unit that detects whether or not the biological sensor unit 6 (the lower surface 2a side of the housing 2) is in contact with the biological surface B. That is, the living body sensor unit 6 detects whether or not the force is in contact with the living body surface B, and generates light from the living body to generate a pulse signal. It will have LED4 and PD5 which have the function of detecting.

[0025] Further, as shown in FIG. 7, the biological information measuring device 1 is disposed on the lower surface 2a side of the housing 2, transmits and reflects light emitted by the LED 4, and also transmits light scattered backward in the living body. A cover glass 23 for transmitting light is provided. Further, the PD 5 receives the light propagating through the cover glass 23 and the backscattered light of the biological force transmitted through the cover glass 23.

Further, the data processing unit 7 includes a determination unit 7a that determines whether or not the living body and the living body sensor unit 6 come into contact with each other based on a light reception signal received by the PD 5, and determines whether or not a force is applied.

[0027] The housing 2 is made of a metal material such as plastic or aluminum and has a predetermined thickness, for example, a substantially rectangular shape when viewed from above. A substantially square glass plate 10 is fitted in the center of the upper surface 2b of the housing 2, and a display unit 11 for displaying the calculated pulse rate and other various information is provided inside the glass plate 10. Are arranged.

As shown in FIGS. 5 and 6, a main board 12 is provided in the housing 2, and the data processing section 7, the display section 11, and the chargeable section are provided on the main board 12. A rechargeable battery 13, a memory 14 for recording a pulse rate, a sub-board 15, and various other electronic components are electrically connected by mounting or wiring.

[0029] The data processing unit 7 includes an IC component such as a CPU, amplifies the generated pulse signal by an amplifier or the like, and then performs a predetermined process such as a fast Fourier transform process (FFT process). It has a function of calculating the pulse rate by analyzing the processing result. Further, the data processing section 7 records the calculated pulse rate in the memory 14, and displays the calculated pulse rate on the display section 11 based on an input from each button 20 described later. Further, the data processing section 7 has a function of comprehensively controlling other components.

The display unit 11 is, for example, a liquid crystal display such as an LCD (Liquid Crystal Display), and has a time display function of displaying a time counted by a crystal oscillator (not shown), for example, in addition to the pulse rate described above. And a function for displaying various other information. For example, time, date, day of the week, remaining power of the rechargeable battery 13 and the like can be displayed.

As shown in FIGS. 1 and 2, a plurality of buttons 20, for example, Three buttons 20 are provided on the upper surface 2b of the housing 2 and below the display unit 11 (below in FIG. 1), and one button 20 is provided on a side surface of the housing 2. By pressing each of these buttons 20, various operations can be performed. For example, operations such as starting and stopping pulse measurement, switching the display between pulse rate and time, and transmitting pulse rate data recorded in the memory 14 to an external device can be performed. Te!

Further, an external connection terminal (charging means) 21 is provided on a side surface of the housing 2 to supply the external power of a charger or the like to the rechargeable battery 13 by supplying electric power to charge the battery. Note that a cover or the like may be attached so as to cover the external connection terminal 21 to protect the external connection terminal 21. By doing so, the external connection terminal 21 can be protected from water droplets, dust, and the like, which is more preferable. In addition, not only the external connection terminal 21 but also a transformer and the like for supplying power to the charger and the housing 2 may be provided to charge the rechargeable battery 13 in a non-contact state. .

The light receiving signal output from the PD 5 is sent to the data processing unit 7 via the flexible board 24, the sub board 15 and the main board 12. Further, the light propagating in the cover glass 23 and received by the PD 5 is sent to the determination unit 7a.

[0034] The determining unit 7a receives the light receiving signal output from the PD 5 as a voltage, and constantly compares the voltage value with a preset threshold voltage α [V]. If the output light receiving signal is equal to or lower than the threshold voltage α [V] while the LED 4 is in the OFF state, it is determined that the LED 4 and the PD 5 are not in contact with the living body surface Β. On the other hand, if the light receiving signal output from the PD 5 is equal to or higher than the threshold voltage α [V], the LED 4 is turned on. If the light receiving signal output from the PD 5 is equal to or higher than the threshold voltage β [V], it is determined that the LED 4 and the PD 5 are not in contact with the surface of the living body. On the other hand, if the light receiving signal output from the PD 5 is equal to or lower than the threshold voltage β [V], it is determined that the LED 4 and the PD 5 are in contact with the living body surface Β. That is, the data processing unit 7 is set to control the operation of the LED 4 so as to emit the LED 4 light based on the detection result. In addition, not only in this case, for example, You can set to not perform FFT processing when it is detected!

[0035] The fixing means 3 has a first band 30 and a second band 31 whose base end is attached to the housing 2 and which can be attached to the wrist A. The first band 30 and the second band 31 are provided in the longitudinal direction of the housing 2 (vertical direction in FIG. 1) so as to face each other with the housing 2 interposed therebetween. Further, both bands 30 and 31 are formed of a stretchable elastic material.

[0036] The first band 30 has a buckle 30a and a tanda 30b attached to the tips. In the second band 31, a plurality of insertion holes 3la into which the tundas 30b are inserted are formed along the longitudinal direction of the second band 31. Thus, the lengths of the first band 30 and the second band 31 can be adjusted according to the thickness of the wrist A of the user.

A case will be described in which the biological information measuring device 1 configured as described above calculates a pulse rate while being worn on the wrist A.

First, as shown in the flowchart of FIG. 8, the power of the PD 5 is turned on by pressing the button 20 to switch to the pulse measurement mode (step S1). Here, first, the voltage of the light receiving signal of the light received by the PD 5 is detected while the LED 4 is in the OFF state (step S2). The light received by the PD 5 is output as a voltage to the determination unit 7a of the data processing unit 7. In this case, the determination unit 7a constantly compares the detected voltage value with the threshold voltage α [V] (step S3), and when the detected voltage value is equal to or higher than the threshold voltage a (step S3 “ NO ”), and turns on LED4 (step S4). Again, the determination unit 7a of the data processing unit 7 constantly compares the detected voltage value with the threshold voltages j8 [V] and γ [V] (step S5), and determines whether the detected voltage value is the threshold voltage “ | 8 or more and γ or less ”(Step S5“ YES ”), it is determined that LED4 and PD5 are in contact with body surface B.

On the other hand, when the voltage output from the PD 5 is less than or equal to the threshold voltage a while the LED 4 is in the OFF state (“YES” in step S3), it is determined that the LED 4 and the PD 5 are not in contact with the biological surface B. . When the voltage output from the PD 5 is not the threshold voltage `` j8 or more and γ or less '' when the LED 4 is in the ON state (Step S5 `` NO ''), it is determined that the LED 4 and the PD 5 are not in contact with the living body surface Β. to decide. That is, the data processing unit 7 controls the (LED4 and) PD5 Make sure that it is in contact with the living body surface B.

In the present embodiment, the data processing unit 7 always compares the detected voltage value with the threshold voltage. For example, the data processing unit 7 compares only before measuring a pulse, or compares before and after measuring a pulse. It doesn't matter if it's something.

As shown in FIGS. 2 and 3, both bands 30 and 31 are wound so as to wind the wrist A of the user, and the band 30b of the first band 30 is moved to the second depending on the size of the wrist A. When the determination unit 7a determines that the housing 2 is attached to the wrist A, the data processing unit 7 irradiates light from the LED 4 toward the living body. The irradiated light is absorbed and scattered by tissues and blood such as fat and muscle in the living body, and a part of the irradiated light is detected by the PD5 as backscattered light. The detected light fluctuates as the blood volume changes due to pulsation. When the PD 5 receives the backscattered light, the data processing unit 7 generates a pulse signal (biological information signal) according to the change in the amount of received light. That is, the amount of backscattered light of the light emitted from the LED 4 fluctuates according to the blood flow fluctuation in the arteries and arterioles inside the wrist A (living body). It can receive backscattered light according to the wave. Thus, the PD 5 can generate a pulse signal.

[0042] After amplifying the pulse signal, the data processing unit 7 performs predetermined processing such as FFT processing, and then performs analysis to calculate the pulse rate. Then, the data processing unit 7 records the calculated pulse rate in the memory 14 and displays the calculated pulse rate on the display unit 11 based on the operation of each button 20.

The user can easily display the calculated pulse rate on the display unit 11 and confirm it by pressing each button 20 when necessary, which is convenient for use. In addition, the user can operate the buttons 20 to check other information other than the pulse rate, such as the time and the remaining power of the rechargeable battery 13, on the display unit 11. ,.

Further, as described above, the user tightens the housing 2 with the two bands 30 and 31 with a predetermined force and wears the housing 2 on the wrist A. Therefore, even if the user wears the housing 2 for a long time, the user may feel a feeling of oppression. Because there is no, you do not feel uncomfortable.

[0045] The LED 4 and the PD 5 are pressed toward the lower surface 2a side of the housing 2 (outside the housing 2) by the elasticity of the flexible substrate 24 and are as close as possible to the living body surface B. It can be calculated with high accuracy. When charging the rechargeable battery 13 with electric power, for example, the charging can be performed by connecting a charging cord or the like connected to a charger to the external connection terminal 21, and a normal battery can be charged. Need not be provided separately. Therefore, it is possible to reduce maintenance costs. In addition, a sound output means such as a buzzer for outputting sound is provided in the housing 2, and when the charge amount of the rechargeable battery 13 decreases to near "0", sound is output to charge the battery (charging timing). ) May be configured to be notified.

As described above, according to the biological information measuring device 1 of the present embodiment, based on the light received by the PD 5 when the light emitting state of the LED 4 is changed, the LED 4 and the PD 5 Since contact force is detected, contact with the biological surface B can be detected with a simple configuration. Therefore, even when external light enters the PD 5, it is possible to accurately recognize the contact with the biological surface B, and it is possible to detect biological information with high accuracy.

[0048] The technical scope of the present invention is not limited to the above embodiment, and various changes can be made without departing from the spirit of the present invention.

For example, as shown in FIG. 9, the cover glass 23 may be provided with a reflection surface 23a that is arranged between the LED 4 and the PD 5 and reflects a part of the light propagating in the cover glass 23. In this configuration, of the light emitted by the LED 4, the light propagating inside the cover glass 23 is reflected by the reflecting surface 23 a toward the living body surface B. For this reason, when measuring the biological information, it is possible to block light that propagates in the cover glass 23, which becomes noise light, so that it is possible to improve the SN ratio when generating a pulse signal.

Alternatively, as shown in FIG. 10, the PD 5 and the cover glass 23 are disposed apart from each other, and one end 4 Oa is close to the cover glass 23 and the other end 40 b is close to the light receiving surface 5 a of the PD 5. A bundled optical fino O may be provided. In this configuration, since the optical fiber 40 is disposed in the gap between the PD 5 and the force bar glass 23, light that has passed through a surface portion such as the epidermis of the living body surface B is reflected on the outer peripheral surface of the optical fiber 40. Is reflected. Light that has passed only through the surface of the body surface B, such as the epidermis, does not contain much biological information, so by blocking this light, it enters the optical fiber 40, propagates through the optical fiber 40, and travels to the PD5. Most of the guided light is light that has passed deep into the body below the dermis, It becomes light that contains a lot of information.

Further, as shown in FIG. 11, a concave portion (light collecting portion) 41 for collecting the backscattered light from the living body may be formed in a portion of the cover glass 23 facing the PD 5. In the case of this configuration, the light power concave portion 41 irradiated by the PD 5 and scattered backward in the living body is efficiently condensed on the light receiving surface 5a of the PD 5. Therefore, when a pulse signal is generated by the PD 5, the light receiving area of the PD 5 can be reduced, so that the overall size of the biological information measuring device can be reduced. Note that the light-collecting portion may have a convex shape because it only needs to collect light on the light-collecting surface 5a of the PD 5.

[0052] Further, the LED 4 and the PD 5 are used for detecting contact with the body surface B, and are configured to also receive the backscattered light of the body force for generating the pulse signal. Instead, as shown in FIG. 12, a biological information measuring device 50 provided with a detection unit 53 having another pair of LEDs 51 and PD52, and a light shielding plate 54 for shielding the LEDs 4, PD5 and the LEDs 51, PD52. There may be. In this configuration, the LED4 and PD5 detect contact with the body surface B, and the LEDs 51 and PD52 receive the backscattered light, which is a biological force for generating a pulse signal. The PD52 receives the backscattered light required to generate it.

Further, by providing a restriction on the interval between the LED 4 and the PD 5, it is possible to prevent light emitted from the LED 4 from being reflected on the surface of the cover glass 23 and entering the PD 5. Figure 13 and Table 1 show examples of the positional relationship between LED4 and PD5 when acrylic with a refractive index of 1.5 is used as the material for the power bar glass.

[Table 1]

Data XY Zi Z2 Z3 a 0.1 0.5 0.7 2.21 1033 2.91 1083 b 0.5 0,5 3.5 2.21 1083 5.71 1 083 c 1 0.5 7 2.21 1083 9.21 1 083 d 0.1 1 0.7 4.4221 66 5.1 221 66 e 0.5 1 3.5 4.4221 66 7.922166 f 1 1 7 4.422 166 1 1.4221 7

[0055] The PD 5 has a structure in which the light receiving surface 5a is one step lower than the upper surface of the package 5b. The LED 4 and the top surface of the package 5b are arranged flush (to be flush with each other). Here, the distance between these and the cover glass 23 is X, and the thickness of the cover glass 23 is Y. At this time, of the light emitted by the LED 4, the (shortest) distance Z1 at which the reflected light on the lower surface 23 b of the cover glass 23 does not enter the light receiving surface 5 a and the light once reflected inside the cover glass 23 is reflected on the light receiving surface 5 a. The (shortest) distance Z3 that does not enter depends on X and Y. As X and Y become longer, Zl and Z3 become longer. Conversely, as X and Y become shorter, Zl and Z3 become shorter. In this way, the design values shown in Table 1 above can be set according to the region in which the reflected light is blocked.

Further, in the above embodiment, the pulse rate is described as an example of the biological information. However, the present invention is not limited to the pulse rate and may be any biological information.

Further, a function such as a wireless communication unit capable of wirelessly communicating with another electronic device may be added to the housing. By doing so, the pulse rate recorded in the memory can be transmitted to an external electronic device by wireless communication such as Bluetooth, and various information can be obtained in the memory.

Example

[0058] Detected by PD5 when using the biological information measuring device 1 according to the embodiment. The output result will be described.

In the present embodiment, the voltage threshold oc when the LED 4 is in the OFF state is 1.9 [V], and the voltage threshold | 8 and the voltage threshold γ when the LED 4 is in the ON state are 0.4 [V]. , 1.8 [V]. The PD 5 used here will be described on the assumption that the output voltage value decreases as the incident light intensity increases. In other words, a measured voltage of less than α is 1.9 [V] or less, and a measured voltage of | 8 or more and γ or less is 0.4 [V] or more and 1.8 [V] or less. It is shown that.

In FIG. 14, “wearing: X” indicates a state in which the biological information measuring device 1 is not worn on the wrist Α, “wearing: 〇” indicates a worn state, and “LED lighting: X”. Indicates that the LED4 is on and the LED is on (OFF state), and “LED ON: 〇” indicates that the LED4 is on and on (ON state). As shown in FIG. 14, state 1 shows a state in which biological information measuring device 1 is not mounted on wrist A in a dark state without external light. First, when LED4 is OFF, there is no external light or LED4 light, so no light is incident on PD5, so the output voltage (measured value) from PD5 is about 2 [V]. Next, when LED 4 is turned on, there is no external light, but the light illuminated by LED 4 and reflected on the surface of cover glass 23 and the light propagated inside are incident on PD 5, so the output voltage from PD 5 (measurement Value) slightly exceeds 1.8 [V].

Next, state 2 shows a state in which biological information measuring device 1 is worn on wrist A in a dark state without external light. First, when LED4 is OFF, there is no external light or LED4 light, so no light is incident on PD5, so the output voltage (measured value) from PD5 is about 2 [V]. Next, when LED 4 is turned on, there is no external light, but the light radiated by LED 4 and propagated through force bar glass 23 and light scattered back in the living body enter PD 5, so the output voltage from PD 5 (Measured value) is about 1.4 [V].

Next, state 3 shows a state in which the intensity of external light is about 600 Lx and the biological information measuring device 1 is not mounted.

First, when the LED 4 is in the OFF state, there is no light from the LED 4, but since there is external light, the output voltage (measured value) from the PD 5 is about 0.12 [V]. Next, when the LED 4 is turned on, the external light and the light radiated by the LED 4 and propagated in the cover glass 23 enter the PD 5, so that the output voltage (measured value) from the PD 5 is about 0.11 [ V]. These results are outside Although it differs slightly depending on the light intensity, the state of the living body surface, the distance between LED4 and PD5, etc., from these results, if the measured value of PD5 is below 1.9 [V] when LED4 is OFF, Assuming that external light is incident on PD5, it can be determined that LED4 and PD5 are not in contact with living body surface B. If the measured value of PD5 exceeds 1.9 [V] with LED4 OFF, and if the measured value of PD5 exceeds 1.8 [V] with LED4 turned on, Assuming that the backscattered light from the living body has not entered PD5, it is determined that LED4 and PD5 are not in contact with living body surface B, LED4 is turned on, and the measured value of PD5 is 0.4 [V]. In the case below, the reflected light from the object other than the living body is incident on the PD 5, and it can be determined that the LED 4 and the PD 5 and the living body surface B are in a non-contact state.

In the present embodiment, the thresholds are set to 1.9 [V], 1.8 [V], and 0.4 [V], respectively, but the set value of the threshold is not limited to this.

Industrial applicability

[0065] According to the biological information measuring device of the present invention, the presence or absence of contact is detected based on the light received by the light receiving unit when the light emitting state of the light emitting unit is changed. Thus, contact with a living body can be detected. Therefore, even when external light enters the light receiving unit, the contact with the living body can be accurately recognized, and the calculation of the biological information can be performed with high accuracy.

Claims

The scope of the claims

[1] body and

A biological sensor unit provided on the main body and irradiating light toward a living body to generate a biological information signal according to the amount of backscattered light of the biological force;

A biological information calculation unit that is provided in the main body and calculates biological information based on the biological information signal;

A detection unit disposed on the lower surface side of the main body, the detection unit detecting whether the biological sensor unit has contacted the surface of the living body,

The light emitting unit that irradiates the living body with light,

A cover glass disposed on the lower surface of the main body for transmitting and reflecting light emitted by the light emitting unit and transmitting light scattered back in the living body; and a light for receiving light transmitted through the cover glass. A light receiving section,

A biological information measuring device, comprising: a determination unit configured to determine whether or not the living body and the biological sensor unit are in contact with each other based on a light reception signal received by the light receiving unit.

[2] The claim 1 wherein the light receiving unit receives backscattered light of the biological force transmitted through the cover glass and generates a biological information signal according to the amount of backscattered light. The biological information measuring device as described in the above.

3. The cover glass according to claim 2, further comprising a reflection surface disposed between the light emitting unit and the light receiving unit and reflecting a part of light propagating in the cover glass. The biological information measuring device as described in the above.

[4] The biological information measurement according to claim 2, further comprising a bundled optical fiber having one end disposed on the cover glass and the other end disposed close to the light receiving surface of the light receiving unit. apparatus.

[5] The living body information measurement according to claim 1, further comprising a condensing unit that collects backscattered light from the living body on a surface of the cover glass facing the light receiving unit. apparatus.