JP2005160640A - Biological state detector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a biological state detector surely detecting a pulse even if a body moves, and highly sensitively detecting a pulse wave and the body motion even if being worn on a portion except for a peripheral part such as a finger. <P>SOLUTION: When subjecting a pulse wave detection signal including pulse components and body motion components and a body motion detection signal more intensified with the body components compared with the pulse wave detecting signal to an FFT, the biological state detector determines the presence/absence of the body motion based on the amplitude of the body motion detection signal and the analytical results of both detecting signals (S200), and when the body moves (S210-Y), determines the constancy of the body motion based on the analytical results of both detecting signals (S240). Based on the determination results, when the body moves (S210-Y), when the body moves and has homeostasis (S240-Y), and when the body moves but has no homeostasis (S240-N), the pulse components are specified (S220, S250 and S260) by methods according to the respective states. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a biological state detection device that detects a biological state such as a pulse rate and a pulse interval.

  In recent years, there has been an increasing need for monitoring the heart rate (heart rate) during exercise such as daily life and jogging for health management applications. In order to detect the heart rate, an electrocardiograph generally measures an action potential generated with a heartbeat from the chest, and calculates from an R wave interval time appearing in the measurement result (electrocardiogram). However, in measurement with an electrocardiograph, it is necessary to attach electrodes to the body of the subject, which not only bothers the subject but also restricts the movement of the subject.

  Therefore, a method using an optical pulse wave sensor that can be easily mounted on a finger, a temple, or the like instead of an electrocardiograph has been proposed. A pulse wave is a change in pressure in the artery that occurs according to the heart rate, and is transmitted to the peripheral artery as a wave. The optical pulse wave sensor uses the light absorption characteristics of hemoglobin in the blood to blood in the peripheral artery. Measure the wave volume change.

  When the pulse wave sensor is used, the pulse rate N is calculated from the pulse wave appearance interval W as shown in FIG. However, when body motion occurs at the site where the pulse wave sensor is attached, the blood flow in the peripheral artery is disturbed, and the detected pulse wave has a peak synchronized with the body motion, regardless of the pulse (heart rate). Appears, and the pulse rate calculated using the pulse wave sensor does not match the actual pulse rate. Moreover, the peak (body motion component) based on the body motion may appear in a frequency region overlapping with the peak based on the pulse (pulse component), and cannot be simply removed by a filter or the like.

  In order to solve such a problem, for example, a body motion sensor (acceleration sensor) for detecting body motion is provided separately from the pulse wave sensor, and when the body motion is detected by the body motion sensor, the pulse wave sensor An apparatus is known that extracts a pulse component by removing a body motion component specified from a detection signal of a body motion sensor from a frequency analysis result (spectrum) of an obtained detection signal (see, for example, Patent Document 1). .

In addition, optical pulse wave sensors that emit two types of light with different wavelengths are used, the light absorption characteristics of blood components change according to the wavelength of light, and the movement of a living body affects the blood flow rate. Based on the detection signal detected for each of the light with different wavelengths, the ratio of the amplitude of the peak frequency component included in each detection signal and the change thereof, the discrimination between the pulse component and the body motion component, An apparatus for detecting the exercise intensity of a living body is also known (for example, see Patent Document 2).
Japanese Patent No. 2816944 JP-A-7-88092

  However, in the conventional apparatus described in Patent Document 1, although a small optical pulse wave sensor is used in order to prevent the movement of the subject from being restricted at the time of measurement, the body motion is separate from the pulse wave sensor. Since the sensor must be used together, there is a problem that the number of components of the apparatus increases.

  On the other hand, the conventional device described in Patent Document 2 does not require a separate body motion sensor, so that the device can be made compact. However, the relationship between the body motion component and the pulse component varies depending on the sensor wearing state and individual differences (for example, the strength of cardiopulmonary function, the thickness of subcutaneous fat, etc.). Since the influence of the reflected light from the surface of the skin that is strongly subjected to the above is not taken into consideration, there is a problem that the pulse and the momentum cannot be accurately obtained by the unique arithmetic processing used in this conventional apparatus.

  In particular, in consideration of the convenience of the subject, when a pulse wave sensor is attached to an arm, leg, etc., the detection sensitivity of the pulse wave is reduced due to the influence of subcutaneous fat compared to the case where it is attached to a peripheral part such as a finger. Therefore, the pulse wave component is buried in the body motion component, and there is a problem that the detection accuracy is lowered.

  In order to solve the above problems, the present invention accurately detects the pulse even when there is body movement, and also detects the pulse wave and body movement with high sensitivity even when worn on other than a peripheral part such as a finger. An object of the present invention is to provide a living body state detection device.

  In the biological state detection device of the present invention made to achieve the above object, the pulse wave sensor has a light emitting unit that generates light to be irradiated to the subject, and a light receiving unit that receives reflected light from the subject, A pulse wave detection signal including a pulse component synchronized with the body motion component and a body motion component synchronized with the body motion, and a body motion detection signal in which the body motion component is emphasized compared to the pulse wave detection signal.

  Then, the analysis means performs frequency analysis on the detection signal (pulse wave detection signal, body motion detection signal) from the pulse wave sensor, and the body motion determination means at least detects the signal from the pulse wave sensor or the analysis means. Based on one of the analysis results, the presence / absence of body movement is determined. Further, when the body movement determination means determines that there is body movement, the stationarity determination means determines whether the body movement is based on the analysis result of the analysis means. Determine the steadiness of body movement.

Then, the pulse component extraction means extracts a pulse component from the pulse wave detection signal based on the analysis results of these analysis means and the determination results of the body motion determination means and the continuity determination means.
As described above, in the present invention, the pulse wave sensor outputs not only the pulse wave detection signal including the pulse component and the body motion component but also the body motion detection signal in which the body motion component is emphasized. The body motion of the subject can be detected with high accuracy without providing a body motion sensor separate from the pulse wave sensor using the above.

  When extracting the pulse component from the pulse wave detection signal, not only the presence / absence of body movement, but also the state of body movement (presence / absence of steadiness) is taken into consideration. The component can be correctly identified, and the extraction of the pulse component and the detection of the biological state such as the pulse rate and the pulse interval can be performed with high accuracy.

  By the way, in order to output the pulse wave detection signal and the body motion detection signal from the pulse wave sensor, specifically, for example, the first light emitting unit emits light when the pulse wave sensor outputs the pulse wave detection signal. The light-emitting element includes a second light-emitting element that emits light when the pulse wave sensor outputs the body movement detection signal, and the first light-emitting element is a blood component (for example, hemoglobin) than the second light-emitting element. It is conceivable to use one that emits light at a wavelength having a large absorbance.

  In this case, the pulse component included in the pulse wave detection signal detected using the first light emitting element is emphasized, and conversely, the pulse component included in the body motion detection signal detected using the second light emitting element is small. Thus, the body motion component is relatively emphasized.

  Specifically, for example, a device that emits light in the green region (approximately 520 nm) is used as the first light-emitting device, while a device that emits light in the infrared region (approximately 950 nm) is used as the second light-emitting device. it can.

  Further, the pulse wave sensor is configured such that the light emitting unit (first light emitting element, second light emitting element) and the light receiving unit are housed in the housing, and the emitted light from the light emitting unit and the reflected light to the light receiving unit. When the translucent plate is arranged in the opening that allows the light to pass through, the translucent plate transmits the radiated light based on the second light emitting element at the first portion that transmits the radiated light based on the first light emitting element. You may comprise so that it may have the shape which protruded toward the exterior of the housing | casing from the 2nd site | part made.

  In this case, since the first part of the translucent plate is more closely attached to the subject than the second part, when the first light emitting element emits light, the emitted light is more emitted than when the second light emitting element emits light. It becomes easy to reach the blood vessel, and reflected light from the blood vessel is also easily received by the light receiving unit. Further, the reflection of the skin that can be noise can be reduced, and the S / N can be improved.

  That is, when the first light emitting element is caused to emit light, the pulse component contained in the reflected light is larger than when the second light emitting element is caused to emit light. Conversely, when the second light emitting element is caused to emit light, The pulse component included in the reflected light becomes smaller than when the one light emitting element is caused to emit light, and the body motion component is relatively emphasized.

  The translucent plate preferably has at least a first portion protruding outward from the housing. Further, the housing has an outer periphery that is outside the other portion of the surface where the opening is formed. It is desirable to have a shape protruding toward

  In the former case, the first part of the translucent plate can be reliably brought into close contact with the subject without being obstructed by the casing. Since it protrudes from this part, not only a part 1st site | part but the whole translucent board can be reliably stuck to a test subject.

  Since the pulse wave sensor (translucent plate) is in close contact with the subject as described above, the biological state detection device of the present invention can be used for parts other than the peripheral part such as a finger (for example, arms, legs, torso). Etc.), it is possible to detect pulse waves and body movements with high sensitivity.

  The light receiving portion may be configured by a pair of light receiving elements provided for each of the first light emitting element and the second light emitting element, but is configured by a single light receiving element shared by both light emitting elements. May be. In this case, the components of the pulse wave sensor can be reduced, and the sensor can be downsized.

  By the way, when the subject has body movement, the amplitude of the detection signal (pulse wave detection signal, body movement detection signal) from the pulse wave sensor changes according to the body movement. In addition, since the pulse does not change drastically when normal, the pulse component included in the detection signal from the pulse wave sensor (especially the pulse wave detection signal) does not have a large harmonic and the subject does not move. The peak frequency component detected with sufficient intensity from the pulse wave detection signal is only one based on the pulse component. Furthermore, the body motion detection signal also includes a pulse component, but in the body motion detection signal in which the body motion component is emphasized, if the extracted peak frequency component is based on the pulse component, the intensity of the peak frequency component Is smaller than the intensity of the peak frequency component of the same frequency detected by the pulse wave detection signal.

  Based on these facts, as the body motion determination means, specifically, it is determined that there is body motion when the amplitude of the body motion detection signal or the difference value of the body motion detection signal is larger than a preset threshold value. The intensity ratio between the first peak motion component and the second largest peak frequency component of the pulse wave detection signal in the frequency region where the fundamental wave of the pulse component can exist is set in advance. Second body motion determination for determining that there is body motion when the ratio is less than or equal to the ratio (for example, about 3 to 10), that is, when the peak frequency component other than the maximum peak frequency component has an intensity that cannot be ignored. The intensity of the peak frequency component of the body motion detection signal in which the intensity of the maximum peak frequency component of the pulse wave detection signal in the frequency region where the fundamental wave of the pulse component can exist is the same frequency as this maximum peak frequency component Is In some cases, there may be a third body motion determining means for determining that there is a body motion, and these first to third body motion determining means may include only one, but any two or all of them. It is desirable to have.

In addition, it is known that when the body motion is stationary, the fundamental wave and harmonics of the body motion component appear clearly, and these are detected as peak frequency components.
Therefore, as the stationarity determination means, specifically, when the intensity ratio between the maximum peak frequency component of the body motion detection signal and the second largest peak frequency component is larger than a preset ratio, it is determined that stationarity exists. The first stationary state determination means or the maximum peak frequency component of the body motion detection signal and the second or third largest peak frequency component are in a relationship in which one is a fundamental wave and the other is a second harmonic. A second stationarity determining unit for determining that there is stationarity is conceivable. These first and second stationarity determining units may include only one of them, but it is desirable to include both. .

  Further, as the pulse component extraction means, specifically, a first pulse component extraction means for extracting the maximum peak frequency component of the pulse wave detection signal as a pulse component when the body movement determination means determines that there is no body movement, The maximum peak frequency component of the pulse wave detection signal within the frequency range where the fundamental wave of the pulse component can exist, excluding the fundamental wave and harmonics specified by the body motion component specifying means, except those whose frequency matches. When the intensity ratio between the second peak frequency component and the second largest peak frequency component is larger than a preset ratio, the second pulse component extraction means for extracting the maximum peak frequency component as a pulse component, and the overlap estimation means estimate that there is no overlap In the case where it is estimated that there is an overlap by the third pulse component extraction means for extracting the maximum peak frequency component of the pulse wave detection signal within the search range as a pulse component, and the overlap estimation means Extracting the fourth pulse component for estimating the frequency component corresponding to the pulse component from the analysis result of the analyzing means within the predetermined range centered on the maximum peak frequency component of the pulse wave detection signal within the search range Means can be considered. However, among these first to fourth pulse component extracting means, it is sufficient that at least the first pulse component extracting means is provided, and in addition to this, with the second to fourth pulse component extracting means, It can be made more accurate up to pulse rate detection during body movement.

  The body motion component specifying unit specifies the fundamental wave and the harmonic of the body motion component when the stationarity determining unit determines that the stationarity is present, and the overlap estimation unit determines the pulse specified by the previous measurement. Based on the maximum peak frequency component of the pulse wave detection signal within a preset search range centered on the frequency of the component, and the fundamental wave and harmonics of the body motion component specified by the body motion component specifying means, Presence or absence of overlap between the pulse component and the body motion component is estimated.

  That is, if the first pulse component extraction means is provided, the pulse component can be extracted when the subject has no body movement, and if the second pulse component extraction means is provided, the subject has body movement and the body movement. The pulse component can also be extracted even when there is continuity. Further, if the third and fourth pulse component extraction means are provided, even if there is no peak frequency component that can be clearly specified as the pulse component, it is estimated from the frequency of the pulse component specified in the previous measurement. The pulse component can be extracted.

In particular, in the fourth pulse component extracting means, specifically, the analysis result of the pulse wave detection signal and the body motion detection signal is normalized with respect to intensity, and the frequency component that maximizes the difference between the two is estimated as the pulse component. There is a so-called FFT subtraction method. This is because when the frequency resolution is small, the pulse component and the body motion component are difficult to overlap, but when the frequency resolution is large, both components are likely to overlap, so the FFT subtraction method is more than the method of simply detecting the peak. The pulse rate can be detected with higher accuracy.
Further, in the second to fourth pulse component extraction means, a correlation value between the analysis result of the pulse wave detection signal and the analysis result of the body motion detection signal is calculated for each preset divided section, and the correlation value is minimum. A so-called correlation coefficient method may be used in which a frequency component having the maximum intensity in a divided section is estimated as a pulse component.

  By the way, the living body state detection apparatus of the present invention may be configured such that the index calculation means calculates an index consisting of at least one of the pulse rate and the pulse interval based on the pulse component extracted by the pulse component extraction means. Good.

  Then, the index calculation means is based on the frequency component of the pulse wave detection signal included in a preset frequency range centered on the pulse component extracted by the pulse component extraction means, and the intensity of the frequency component is used as a weight. If the weighted average frequency is obtained and the index is calculated from the weighted average frequency, the apparent resolution can be improved over the frequency resolution of the analysis result obtained by the analyzing means.

Moreover, the biological state detection device of the present invention may be configured such that the light emission intensity adjusting means adjusts the light emission intensity at the light emitting unit based on the amplitude of the pulse wave detection signal output from the light receiving unit.
That is, the amount of attenuation of light from the body surface to the blood vessel is affected by subcutaneous fat and the like, and varies greatly depending on the mounting position of the pulse wave sensor and individual differences. Thus, detection can always be performed in an optimum state.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is an explanatory diagram showing an appearance of a living body state detection apparatus 1 to which the present invention is applied and a use state thereof.

As shown in FIG. 1, the biological state detection device 1 according to the present embodiment includes a main body 3 that is formed in the size of a wristwatch and a belt-like attachment portion 5 that is formed integrally with the main body 3.
A display panel 3a is provided on the front side of the main body 3, and a light transmitting plate 3b that constitutes a detection window for allowing light used for detection of biological information to pass therethrough is communicated with an external device or the device. A connector 3c for connecting a cable used for charging 1 is provided.

  As shown in FIG. 1 (b), the living body state detection device 1 is configured so that the back side of the main body 3 on which the light-transmitting plate 3b is formed is brought into contact with the skin of the subject so that the attachment portion 5 can contact the subject. It is fixed to the wrist and ankle. However, the attachment position is not limited to the wrist or ankle, but may be anywhere from the fingertips to the roots of the extremities (arm legs). Moreover, you may comprise the attaching part 5 using a supporter etc. instead of a belt.

  Moreover, the housing | casing which comprises the main body 3 has the peripheral part 3d of the translucent plate 3b protruded from another site | part so that the translucent plate 3b may contact | adhere to a test subject's skin, when the said apparatus 1 is attached to a test subject. In the present embodiment, it has a structure (refer to FIG. 3) of about 0.2 mm. Furthermore, the body 3 is waterproofed so that the subject can take a bath while wearing the living body state detection device 1.

Next, FIG. 2 is a block diagram showing an internal configuration of the biological state detection device 1.
As shown in FIG. 2, the biological state detection device 1 irradiates light through a light transmitting plate 3 b and receives biological light information by receiving reflected light. The information processing unit 20 that processes biological information detected in this way and the battery 15 that is configured to be rechargeable via a cable connected to the connector 3c and that supplies power to each unit of the apparatus.

  Among them, the information detection unit 10 includes a green LED 11a that emits green light (wavelength is about 520 nm in the present embodiment), an infrared LED 11b that emits infrared light (wavelength is about 950 nm in the present embodiment), and the LEDs 11a, 11b, an optical pulse wave sensor 11 including a photodiode (PD) 11c that receives reflected light emitted from the LEDs 11a and 11b, and the LEDs 11a and 11b according to instructions from the information processing unit 20. A driving circuit 12 that drives the PD 11, a detection circuit 13 that generates a detection signal corresponding to the intensity of the reflected light, and an A / D converter 14 that converts the detection signal from the detection circuit 13 into digital data. Become.

  The translucent plate 3b has a portion facing the green LED 11a and the photodiode 11c (hereinafter referred to as “first portion”), that is, a portion serving as a passage path for the emitted light from the green LED 11a and its reflected light. A portion that projects from the peripheral edge 3d of the light plate 3b (0.2 mm in the present embodiment) and faces the infrared LED 11b (hereinafter referred to as “second portion”), that is, a path through which the emitted light from the infrared LED 11b passes. The part which becomes will have a shape (0.2 mm in this embodiment) dented from the peripheral part 3d of the translucent plate 3b. That is, as shown in FIG. 3, when the device 1 is attached to the subject, the portion that becomes the passage path of the emitted light (green light) and the reflected light from the green LED 11 a has a high degree of adhesion with the subject's skin, The part which becomes the passage route of the radiated light (infrared light) from the infrared LED 11b is configured such that the degree of adhesion with the skin of the subject is reduced (or not adhered).

  Then, when the light emitted from the LEDs 11a and 11b toward the subject reaches the capillary artery passing through the subject's body, a part of the light is absorbed by hemoglobin in the blood flowing through the capillary artery, and the rest is reflected by the capillary artery. Scattered. A part of the scattered light enters the PD 11c as reflected light.

  At this time, since the amount of hemoglobin in the capillary artery changes in a wave manner due to blood pulsation, the amount of light absorbed by the hemoglobin also changes in a wave manner. Accordingly, the amount of received light (signal level of the detection signal) reflected by the capillary artery and detected by the PD 11c also changes, so that information on the pulse wave can be obtained from the detection signal.

  Since the blood flow is also affected by body movement, the detection signal from the PD 11c includes not only the pulse component synchronized with the pulse but also the body movement component synchronized with the body movement (see FIG. 19). ). Also, not all of the emitted light reaches the capillaries, and reflected light (surface reflected light) reflected by the surface of the body is also received by the PD 11c, and this surface reflected light also contains many body movement components. It is.

  However, since infrared light has lower light absorption characteristics than green light, the detection signal (body motion detection signal) detected by the PD 11c when the infrared LED 11b is caused to emit is the PD 11c when the green LED 11a is caused to emit light. Compared with the detection signal (pulse wave detection signal) detected at, the pulse component synchronized with the pulse is small, and the body motion component relatively synchronized with the body motion is emphasized.

  In addition, since the green light emitted through the first part of the translucent plate 3b easily reaches the capillary artery passing through the body of the subject and the reflected light from the capillary artery is easily received, the pulse wave detection signal On the other hand, the infrared light irradiated through the second part of the translucent plate 3b is easily reflected on the surface of the skin, and the irradiation position is accompanied by body movement. Since it becomes easy to shake, the detection sensitivity of the pulse component in the body motion detection signal is lowered and the detection sensitivity of the body motion component is improved.

  As a result, in the pulse wave detection signal, as shown in FIG. 4A, the pulse component and the body motion component are detected at a signal level (about 1: 5 in this embodiment) that is not significantly different, In the body motion detection signal, as shown in FIG. 4B, the pulse component is detected at a very small signal level (about 1:50 in this embodiment) compared to the body motion component. Become. FIG. 4 is a schematic diagram showing an outline of a pulse wave detection signal and a frequency spectrum of the body motion detection signal detected when the subject has body motion.

  Then, when the drive circuit 12 is activated by a command from the information processing unit 20, the LEDs 11a and 11b alternately emit light at different timings once every preset sampling interval (50 msec in the present embodiment). In addition, the light emission intensity of each LED 11a, 11b can be adjusted in accordance with a command from the information processing unit 20.

  The A / D converter 14 operates in synchronization with the light emission timing of the drive circuit 12 to thereby detect a pulse wave detection signal detected when the green LED 11a emits light and a body motion detection signal detected when the infrared LED 11b emits light. Are converted into digital data, and the digital data is supplied to the information processing unit 20 as biological information.

  Further, in the detection circuit 13, when detecting the body movement detection signal (when the infrared LED 11b emits light), the light reception signal from the PD 11c is larger than when detecting the pulse wave detection signal (when emitting the green LED 11a). The body motion component is set to be more emphasized.

  Next, the information processing unit 20 detects the presence or absence of the cable connection to the connector 3c, and controls the communication control unit 22 that controls communication with an external device via the cable connected to the connector 3c, and the voltage of the battery 15 And a microcomputer (microcomputer) 24 that is configured around a CPU, a ROM, and a RAM and that performs control of each part of the device, analysis of biological information detected by the information detection unit 10, and the like. And a storage unit 25 that stores biological information detected by the information detection unit 10 and various information generated by the microcomputer 24 based on the biological information, and characters and figures on the display panel 3a according to instructions from the microcomputer 24. And a display control unit 26 for displaying.

  Note that at least a buffer area for storing biological information supplied from the information detection unit 10 is secured in the storage unit 25. This buffer area has a capacity capable of storing data for a preset FFT target period (in the present embodiment, the past 13 seconds (= 260)) or more.

  Then, the microcomputer 24 activates the information detection unit 10 when the device 1 is turned on, and every time biometric information is supplied from the information detection unit 10, data in the buffer area secured in the storage unit 25. Update processing for updating the data, analysis processing for analyzing the data stored in the storage unit 25, index generation processing for obtaining a pulse rate and a pulse interval as an index for evaluating the biological state according to an analysis result in the analysis processing, and an index Display processing for displaying the indicator generated in the generation processing and the state of charge of the battery 15 on the display panel 3a via the display control unit 26, communication with an external device via a cable connected to the connector 3c, In accordance with commands input from the apparatus, various data stored in the storage unit 25 are transferred, settings of each unit of the apparatus 1 are changed, a program executed by the microcomputer 24 is updated, etc. Executing the communication processing for performing.

Details of the analysis processing and index generation processing according to the present invention will be described below.
FIG. 5 is a flowchart showing the contents of the analysis process. The analysis process is started every preset time interval (1 second in the present embodiment) after the information detection unit 10 is started. Further, when the information detection unit 10 is activated, the drive circuit 12 is initialized to a setting for causing the LEDs 11a and 11b to emit light at the maximum intensity.

  When this processing is activated, digital data (20 in this embodiment, respectively) acquired during the unit interval (that is, 1 second) from the previous activation to the present time for each of the pulse wave detection signal and the body motion detection signal. ), The amplitude Vg of the pulse wave detection signal and the amplitude Vir of the body motion detection signal are calculated (S100). Specifically, as shown in FIG. 6A, the maximum value and the minimum value in the digital data acquired during the unit interval may be extracted, and the difference between them may be the amplitudes Vg and Vir.

  Next, assuming that the voltage range in which the pulse wave detection signal is detected is VR (see FIG. 6B), Vg / VR is the lower limit value VL (this embodiment) within the past and specified time (20 seconds in this embodiment). In the embodiment, it is determined whether or not the unit interval of 0.1) or less is equal to or greater than a certain ratio (80% in the present embodiment) (S110). As a result, a command to increase the emission intensity is output to the drive circuit 12 (S120).

  On the other hand, if a negative determination is made in S110, unit intervals in which Vg / VR is equal to or higher than the upper limit value (0.7 in the present embodiment) within a specified time in the past are a certain percentage (80% in the present embodiment). ) Is judged (S130), and if it is above a certain ratio, the LED 11a, 11b is assumed to have an excessive amount of light, and a command to reduce the light emission intensity is output to the drive circuit 12 (S140).

  Next, it is determined whether or not it is time to execute the FFT process (S150). If it is not the FFT execution timing, this process ends. In the present embodiment, the FFT execution timing is set at an interval of 13 seconds. However, the FFT execution timing may be an interval shorter than 13 seconds, for example, an interval of 1 second (that is, every time this process is started), or an interval longer than 13 seconds.

If an affirmative determination is made in S150, an FFT process is executed for each of the pulse wave detection signal and the body motion detection signal (S160). However, in the present embodiment, the digital data for the FFT target period (that is, 260) stored in the buffer area of the storage unit 25 is the target of the FFT processing, and the FFT processing is shown in FIG. As described above, the interpolation data is added so that the number of data to be subjected to the FFT processing is a power of 2 (2 ⁹ = 512 in the present embodiment). That is, it is set so that the analysis is performed with a frequency resolution higher than the actual number of data.

  When this FFT process is completed, a pulse component is extracted based on the analysis result, an index generation process for generating an index indicating a biological state such as a pulse rate and a pulse interval is started (S170), and this process ends. .

  That is, in the analysis process, every time this process is started (ie, 1 second), the amplitude based on the waveform detected during the past unit interval (ie, 1 second) for each of the pulse wave detection signal and the body motion detection signal. Vg and Vir are obtained, and an FFT processing result based on a waveform detected during the past FFT target period (ie, 13 seconds) is obtained at every FFT execution timing (ie, 13 seconds).

Next, the index generation process started in S170 will be described with reference to the flowchart shown in FIG.
When this process is started, first, a body movement determination process for determining the presence or absence of body movement of the subject is executed (S200).

  In this body motion determination process, as shown in FIG. 8, first, from the analysis result of the pulse wave detection signal, within the frequency range where the fundamental wave of the pulse wave exists (in this embodiment, 0.5 to 3.3 Hz). The peak frequency component G1 having the maximum intensity and the peak frequency component G2 having the next highest intensity are extracted (S300), and the frequency component IR1 having the same frequency as the peak frequency component G1 is obtained from the analysis result of the body motion detection signal. Is extracted (S310).

  Then, for each unit section of the FFT target period (past 13 seconds) used for the FFT processing of the body motion detection signal in the previous S180, the amplitude Vir in the unit section is smaller than a preset threshold value. (S320), and if any one exceeds the threshold value, it is determined that there is a body motion (S360), and this process is terminated.

  If the amplitude Vir in each unit section is smaller than the threshold value, the intensity ratio [G1] / [G2] ([X] is the intensity of the frequency component X) of the peak frequency components G1 and G2 of the pulse wave detection signal. Is greater than a predetermined value H1 (10 in the present embodiment) (S330), and if it is equal to or less than the predetermined value H1, it has sufficient strength that cannot be ignored. It is determined that there is a body motion on the assumption that there are a plurality of peak frequency components and the peak frequency component based on other than the pulse, that is, the peak frequency component based on body motion is superimposed (S360), and this processing is terminated. .

  If the intensity ratio [G1] / [G2] of the peak frequency components G1 and G2 is larger than the predetermined value H1, the intensity of the peak frequency component G1 of the pulse wave detection signal extracted in S300 is extracted in S310. It is determined whether or not the intensity of the frequency component IR1 of the motion detection signal is greater than the intensity of the frequency component IR1 (S340). If the intensity of the peak frequency component G1 is less than or equal to the intensity of the frequency component IR1, the peak frequency component G1 is based on body movement. As a matter of fact, it is determined that there is a body motion (S360), and this process is terminated.

On the other hand, if the intensity of the peak frequency component G1 is greater than the intensity of the frequency component IR, it is determined that there is no body movement (S350), and this process is terminated.
That is, the amplitude for each unit interval of the body motion detection signal within the FFT target period is larger than the threshold value in all the intervals, and the peak frequency component having sufficient strength is one in the analysis result of the pulse wave detection signal. Only when there is only one ([G1] / [G2]> H1) and the body motion detection signal is larger than the frequency component of the same frequency ([G1]> [IR1]), it is determined that there is no body motion. In other cases, it is determined that there is a body movement.

  Returning to FIG. 7, it is determined whether the determination result in the body movement determination process (S200) is no body movement (S210). If the determination result is no body movement, a resting pulse component specifying process is performed. Execute (S220). In this process, the peak frequency component G1 of the pulse wave detection signal extracted in S300 of the body movement determination process is specified as a pulse component.

On the other hand, if the determination result in the body movement determination process is that there is a body movement, a continuity determination process for determining whether or not the body movement is stationary is executed (S230).
In this continuity determination process, as shown in FIG. 9, first, four peak frequency components IR1 to IR4 are extracted in descending order from the analysis result of the body motion detection signal (S400). Then, it is determined whether or not the intensity ratio [IR1] / [IR2] of the peak frequency component IR1 having the highest intensity and the peak frequency component IR2 having the next highest intensity is greater than a predetermined value H2 (10 in the present embodiment). (S410) If the intensity ratio [IR1] / [IR2] is equal to or less than the predetermined value H2, the second highest intensity peak frequency component IR2 or the third highest intensity peak frequency component IR3 and the highest intensity. It is determined whether or not the peak frequency component IR1 has a relationship in which one is a fundamental wave and the other is a second harmonic (S420).

  In S410, it is determined that the intensity ratio [IR1] / [IR2] of the peak frequency components IR1 and IR2 is larger than the predetermined value H2, or in S420, the peak frequency components IR2 and IR3 and the peak frequency component IR1 If it is determined that there is a relationship between the fundamental wave and the second harmonic, the body motion is determined to be stationary (S430), and the body motion component is determined from the peak frequency components IR1 to IR4. The fundamental wave MF1 and the second to fourth harmonics MF2 to MF4 are specified (S440), and this process ends.

  In S440, if an affirmative determination is made in S410, the peak frequency component IR1 is immediately identified as the fundamental wave MF1, whereas if an affirmative determination is made in S420, as shown in FIG. In some cases, the peak frequency component IR1 may become the fundamental wave MF1, but as shown in FIG. 10B, the second or third largest peak frequency component IR2, IR3 (the peak frequency component IR2 in the figure) is fundamental. There is a case where the wave MF1 is reached and the largest peak frequency component IR1 becomes the second harmonic.

  Also, if it is determined in S420 that there is no relationship between the fundamental wave and the second harmonic between the peak frequency components IR2 and IR3 and the peak frequency component IR1, the body motion is not stationary. A determination is made (S450), and this process ends.

  That is, in this process, there is only one peak frequency component with sufficient intensity in the analysis result of the body motion detection signal ([IR1] / [IR2]> H2), or the peak frequency components IR1 to IR1 When IR4 is in the relationship between the fundamental wave and the harmonic wave and the peak frequency component IR1 is the fundamental wave or the second harmonic wave, it is determined that the stationarity exists.

  Returning to FIG. 7, it is determined whether or not the determination result in the stationarity determination means (S230) is stationarity (S240). Is executed (S250), and if the determination result is not stationary, a pulse component specifying process during unsteady motion is executed (S260).

  Among these, in the steady-state pulse component specifying process, as shown in FIG. 11, first, from the analysis result of the pulse wave detection signal, five peaks in descending order of intensity within the frequency range where the fundamental wave of the pulse wave exists. The frequency components G1 to G5 are extracted (S500), and the extracted peak frequency components G1 to G5 that do not overlap with the body motion components MF1 to MF4 are extracted as non-overlapping peak frequency components PM1, PM2,. (S510).

  Whether the intensity ratio [PM1] / [PM2] between the non-overlapping peak frequency component PM1 having the highest intensity and the non-overlapping peak frequency component PM2 having the next highest intensity is greater than a predetermined value H3 (3 in the present embodiment). If the intensity ratio [PM1] / [PM2] is greater than the predetermined value H3 or there is no non-overlapping peak frequency component other than PM1, the non-overlapping peak frequency component PM1 is used as the pulse component. After specifying (S530), this process is terminated (see FIG. 12A).

  On the other hand, if the intensity ratio [PM1] / [PM2] is equal to or less than the predetermined value H3, the search range centering on the frequency corresponding to the pulse rate calculated during the previous measurement (corresponding to ± 10 beats in this embodiment) Frequency range) is determined whether or not the peak frequency components G1 to G5 are present (S540). If none of the peak frequency components G1 to G5 are present in the search range, the previous measurement result is The current measurement result (pulse component) is used as it is (S550), and this process is terminated.

  If any one of the peak frequency components G1 to G5 exists in the search range, the largest one is extracted as a candidate peak frequency component GM (S560), and the candidate peak frequency component GM It is determined whether or not any of the dynamic components MF1 to MF4 matches (S570).

  If the candidate peak frequency component GM does not coincide with any of the body motion components MF1 to MF4, the candidate peak frequency component GM is specified as a pulse component (S580), and this process is terminated. If the candidate peak frequency component GM matches any of the body motion components MF1 to MF4 (see FIG. 12B), the pulse component is specified by the FFT subtraction process (S590), and this process is performed. finish.

  Here, in the FFT subtraction process in S590, as shown in FIG. 13, first, from the analysis result of the pulse wave detection signal, within a predetermined range centered on the candidate peak frequency component GM extracted in the previous S560 (this embodiment) In the embodiment, the frequency components of 5 points on each side (11 points in total) are normalized so that the intensity of the candidate peak frequency component GM is 1 (hereinafter referred to as “normalized pulse wave spectrum Gs”) (S600). At the same time, based on the analysis result of the body motion detection signal, the frequency component within the predetermined range centered on the frequency component having the same frequency as the candidate peak frequency component GM is normalized so that the intensity of the center frequency component becomes 1. (Hereinafter referred to as “normalized body motion spectrum IRs”) (S610). For both normalized spectra Gs and IRs, see FIG.

  By subtracting the normalized body motion spectrum IRs from the normalized pulse wave spectrum Gs, a difference spectrum GIRs (= Gs-IR) is obtained (S620), and the peak frequency component GIRs1 in the difference spectrum GIRs (FIG. 14 (b) )) Is extracted (S630).

  Then, it is determined whether or not the extracted peak frequency component GIRs1 is equal to or greater than a predetermined value H4 set in advance (0.2 in the present embodiment). If the peak frequency component GIRs1 is equal to or greater than the predetermined value H4, The peak frequency component GIRs1 extracted from the difference spectrum is specified as the pulse component (S650), and this process is terminated.

On the other hand, if the peak frequency component GIRs1 is smaller than the predetermined value H4, the candidate peak frequency component GM is specified as a pulse peak (S660), and this process is terminated.
That is, when the body motion is stationary (during steady motion), the peak frequency component extracted from the analysis result of the pulse wave detection signal does not overlap with the body motion components MF1 to MF4 and is sufficiently If there is something with high intensity, the peak frequency component is specified as a pulse component, and if there is no such peak frequency component, it is within the search range where it is estimated that the pulse component exists based on the previous measurement result. The pulse component is specified based on the maximum peak frequency component (candidate peak frequency component GM). In particular, if the candidate peak frequency component GM overlaps any of the body motion components MF1 to MF4, the pulse subtraction component is extracted by applying the FFT subtraction method to the frequency component in the vicinity of the candidate peak frequency component GM. Has been. If the pulse component cannot be specified, the previous measurement result is used.

  Next, in the unsteady motion pulse component identification process, as shown in FIG. 15, first, from the analysis result of the pulse wave detection signal, the nine in descending order of the intensity within the frequency range where the fundamental wave of the pulse wave exists. Peak frequency components G1 to G9 are extracted (S700), and the intensity ratio [G1] / [G9] between the peak frequency component G1 having the highest intensity and the ninth highest peak frequency component G9 is a predetermined value H5 (in this embodiment). 10) It is determined whether or not it is larger (S710). If the intensity ratio [G1] / [G9] is larger than the predetermined value H3, there are many peak frequency components (nine points or more) having sufficient intensity that cannot be ignored, and misjudgment is likely to occur. The previous measurement result (pulse component) is used as the current measurement result as it is (S760), and this process is terminated.

  If the intensity ratio [G1] / [G9] is equal to or less than the predetermined value H3, the search range centering on the frequency corresponding to the pulse rate obtained in the previous measurement (corresponding to ± 10 beats in this embodiment). Frequency range) is determined whether there is only one peak (S720), and if there are a plurality of peaks in the search range (see FIG. 16B), the previous measurement result is used as it is. As a measurement result (S760), this process is terminated.

  If there is only one peak in the search range (see FIG. 16A), a predetermined range centering on the peak frequency component P1 in the search range (in this embodiment, a total of 5 points, 2 points on each side) ) Determines whether or not the intensities of the other frequency components in [] are less than or equal to [P1] / 2 (S730), and if any one of them has a frequency component greater than [P1] / 2, the peak Assuming that the frequency component P1 cannot be said to be a clear peak, the above measurement result is used as it is as the current measurement result (S760), and this process is terminated.

  If the intensities of the other frequency components are all [P1] / 2 or less, it is determined whether or not the peak frequency component P1 overlaps any of the body motion components IR1 to IR4 extracted in the previous S400 ( S740) If it overlaps with any of the body motion components IR1 to IR4, it is assumed that the peak frequency component P1 is unlikely to be a pulse component, and the previous measurement result is used as the current measurement result as it is (S760). finish.

If the peak frequency component P1 does not overlap with any of the body motion components IR1 to IR4, the peak frequency component P1 is specified as the pulse component (S750), and this process is terminated.
In other words, when the body motion is not stationary (unsteady motion), the number of peak frequency components with sufficient intensity extracted from the analysis result of the pulse wave detection signal is relatively small, and the previous measurement When there is only one peak frequency component that forms a clear peak within the search range in which the pulse component is estimated to exist based on the result, and the peak frequency component P1 does not overlap with the body motion components IR1 to IR4 Only the peak frequency component P1 is specified as the pulse component.

  Returning to FIG. 7, when a pulse component is specified by the processing in S220, S250, and S260, an index calculation process (S270) for obtaining an index such as a pulse rate and a pulse interval is executed, and this process is terminated.

  In this index calculation process, as shown in FIG. 17, first, the intensity is calculated based on frequency components within a predetermined range centered on the identified pulse component (in this embodiment, one point on each side for a total of three points). The weighted average frequency fm is calculated as the weight (S800), and the weighted average frequency fm is multiplied by 60 [sec] to calculate the pulse rate N per minute (S810) and the inverse of the weighted average frequency fm. By calculating 1 / fm, the pulse interval W is calculated (S820), and this process is terminated (see FIG. 18).

  Here, although the pulse rate N and the pulse interval W are obtained as indices, for example, when it is determined that the body motion is stationary, the motion pitch is determined from the fundamental wave of the body motion component. May be requested.

  As described above, in the biological state detection device 1 of the present embodiment, a green light reception signal having a large amount of absorption by hemoglobin is used as a pulse wave detection signal, and compared with green light as a body motion detection signal. In addition, a light reception signal of infrared light with a small amount of absorption by hemoglobin is used, and as a translucent plate 3b, when the device is attached to a subject, skin is transmitted in a portion that transmits green light (first portion). In the part (second part) through which infrared light is transmitted and having a high adhesion to the skin, a part having a shape that reduces the adhesion to the skin is used. That is, the pulse wave detection signal detects the pulse component with high sensitivity, while the body movement detection signal detects the body movement component with high sensitivity and suppresses the detection of the pulse component.

The LEDs 11a and 11b that generate green light and infrared light are adjusted in light amount according to the amplitude of the pulse wave detection signal.
Therefore, according to the living body state detection device 1 of the present embodiment, even if the device 1 is attached to a site where the detection sensitivity of the pulse wave is inferior to that of a peripheral part such as a finger, the pulse wave and body are sensitive. The movement can be detected, and even when the mounting state (mounting target or mounting position) changes, the detection can always be performed in an optimal state.

In addition, in the living body state detection device 1 of the present embodiment, the light amount is set to the maximum at the start of measurement, so that the measurement result can be reliably obtained immediately after the start of measurement.
Further, in the living body state detection device 1 of the present embodiment, the pulse wave sensor 11 detects not only the pulse wave detection signal but also the body movement detection signal, and thus the body movement separate from the pulse wave sensor 11. The body movement of the subject can be detected with high accuracy without providing a sensor.

  When extracting a pulse component from the pulse wave detection signal, not only the presence / absence of body movement but also the state of body movement (presence / absence of steadiness) are determined. The body motion component included in the wave detection signal can be correctly specified. As a result, even if the subject has body motion, the pulse component can be extracted with high accuracy, and an index such as the pulse rate N and the pulse interval W can be obtained. It can be obtained with high accuracy.

  Moreover, in the biological state detection device 1 of the present embodiment, the weighted average frequency is obtained based on the frequency component within a predetermined range centered on the pulse component extracted from the analysis result of the pulse wave detection signal, and the pulse is calculated from the weighted average frequency. Since the number N and the pulse interval W are obtained, the pulse rate N and the pulse interval W can be obtained with a resolution higher than the resolution of the analysis result of the FFT process.

  Further, in the biological state detection device 1 of the present embodiment, the presence or absence of body motion is not only the amplitude of the body motion detection signal, but the pulse component has very small harmonics compared to the fundamental wave, and the pulse wave Since the detection signal and the body motion detection signal are determined based on the analysis result of the pulse wave detection signal and the body motion detection signal using the difference in the detection ratio between the pulse component and the body motion component, etc. Body motion can be detected well.

  Furthermore, when it is estimated that the pulse component and the body motion component overlap, the FFT subtraction method is applied only to the frequency band in the vicinity thereof to extract the pulse component. Compared with the conventional apparatus using the FFT subtraction method, the processing amount can be greatly reduced.

  In the present embodiment, the green LED 11a is the first light emitting element, the infrared LED 11b is the second light emitting element, S160 is the analyzing means, S200 is the body motion determining means, S230 is the stationaryity determining means, and S220, S250, and S260 are the pulse. It corresponds to a component extraction means. Also, S320 is the first body motion determining means, S330 is the second body motion determining means, S340 is the third body motion determining means, S410 is the first stationaryity determining means, S420 is the second stationaryity determining means, and S220 is the first. 1 pulse component extracting means, S440 is body motion component specifying means, S500 to S530 are second pulse component extracting means, S540, S560 and S570 are overlapping estimation means, S580 is third pulse component extracting means, and S590 is the fourth pulse component. Extraction means, S270 corresponds to index calculation means, and S110 to S140 correspond to emission intensity adjustment means.

As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said embodiment, It is possible to implement in various aspects.
For example, in the above-described embodiment, the data obtained by adding the interpolation data to the detection data in the FFT target section is used as the processing target data of the FFT processing. Since extraction is easy, FFT processing may be performed using only detected data without adding interpolation data. In this case, the processing amount in the microcomputer 24 can be greatly reduced.

  In the above embodiment, the peak frequency component is normalized so that the intensity of the peak frequency component becomes 1 in the process using the FFT subtraction method (S590). For example, the low frequency component (for example, 0.25 to 0.25) is used. You may normalize so that the average intensity | strength of 0.5 Hz may become equal mutually.

  In the above embodiment, when it is estimated that the pulse component and the body motion component overlap, the pulse component is extracted using the FFT subtraction method. You may comprise so that it may extract using.

  In this correlation coefficient method, the analysis result of the pulse wave detection signal and the analysis result of the body motion detection signal are divided into sections each having a predetermined frequency width (for example, 0.5 Hz), and both signals are analyzed for each divided section. Calculate the resulting correlation coefficient. Then, a divided section where the correlation coefficient is minimum may be extracted, and a frequency component having the maximum intensity in the divided section may be extracted as a pulse component.

Moreover, you may comprise so that a pulse component may be extracted combining several methods, such as applying the FFT subtraction method with respect to the division area where a correlation coefficient becomes the minimum.
Further, the FFT subtraction method or the correlation coefficient method may be used in the unsteady motion pulse component specifying process that is executed when there is a body motion that is not stationary.

  Further, immediately after the biological state detection device 1 is mounted on the subject, a display for prompting the subject to rest is displayed on the display panel 3a, and the measurement is started after the pulse rate is stabilized. May be. In this case, since an accurate pulse rate can be detected at the initial stage of wearing, it is possible to improve the follow-up performance of the pulse rate when the pulse component cannot be extracted thereafter.

It is explanatory drawing which shows the external appearance and use condition of a biological condition detection apparatus. It is a block diagram which shows the internal structure of a biological condition detection apparatus. It is explanatory drawing which shows the structure and use condition of the housing | casing which comprise a pulse wave sensor, and a translucent board. It is a schematic diagram which shows the outline | summary of the frequency spectrum of the pulse wave detection signal detected when a test subject has a body motion, and a body motion detection signal. It is a flowchart which shows the content of the analysis process. It is explanatory drawing for demonstrating the parameter etc. which are used in an analysis process. It is a flowchart which shows the content of the parameter | index production | generation process. It is a flowchart which shows the content of the body movement determination process. It is a flowchart which shows the content of the continuity determination process. It is a graph for demonstrating the operation | movement regarding a continuity determination process. It is a flowchart which shows the content of the pulse component specific process at the time of steady motion. It is a graph for demonstrating the operation | movement in connection with the pulse component specific process at the time of steady motion. It is a flowchart which shows the content of a FFT subtraction process. It is a graph for demonstrating the operation | movement in connection with a FFT subtraction process. It is a flowchart which shows the content of the pulse component specific process at the time of unsteady motion. It is a graph for demonstrating the operation | movement in connection with the pulse component specific process at the time of unsteady motion. It is a flowchart which shows the content of an index calculation process. It is a graph for demonstrating the operation | movement in connection with parameter | index calculation processing. It is a graph which shows the example of a pulse wave waveform.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Living body state detection apparatus, 3 ... Main body, 3a ... Display panel, 3b ... Translucent board, 3c ... Connector, 3d ... Peripheral part, 5 ... Mounting part, 10 ... Information detection part, 11 ... Pulse wave sensor, 11a ... Green LED, 11b ... Infrared LED, 11c ... Photodiode (PD), 12 ... Drive circuit, 13 ... Detection circuit, 14 ... A / D converter, 15 ... Battery, 20 ... Information processing unit, 22 ... Communication control unit, 23 ... Voltage detection unit, 24 ... Microcomputer (microcomputer), 25 ... Storage unit, 26 ... Display control unit.

Claims (22)

A pulse wave detection signal including a light emitting unit that generates light to be irradiated to the subject, and a light receiving unit that receives reflected light from the subject, and includes a pulse component synchronized with the pulse and a body motion component synchronized with the body motion, and A pulse wave sensor that outputs a body motion detection signal in which the body motion component is emphasized compared to the pulse wave detection signal;
Analyzing means for frequency analysis of the pulse wave detection signal and the body motion detection signal output by the pulse wave sensor;
Body movement determination means for determining the presence or absence of body movement based on at least a detection signal from the pulse wave sensor or an analysis result in the analysis means;
When it is determined that there is body movement by the body movement determination unit, continuity determination unit that determines the continuity of the body movement based on the analysis result of the analysis unit;
A pulse component extracting means for extracting a pulse component from the pulse wave detection signal based on the analysis result in the analyzing means, the determination result in the body motion determining means and the continuity determining means;
A biological state detection device comprising: The light emitting unit
A first light emitting element that emits light when the pulse wave sensor outputs the pulse wave detection signal;
A second light emitting element that emits light when the pulse wave sensor outputs the body motion detection signal;
The biological state detection device according to claim 1, comprising:   The biological state detection device according to claim 2, wherein the first light emitting element emits light at a wavelength where the absorbance of the blood component is larger than that of the second light emitting element. The biological state detection device according to claim 3, wherein the first light emitting element emits light in a green region, and the second light emitting element emits light in an infrared region. The pulse wave sensor is
A housing that houses the light emitting unit and the light receiving unit, and that has an opening at a site through which radiated light from the light emitting unit and reflected light to the light receiving unit pass,
A translucent plate provided at the opening of the housing and transmitting light;
With
5. The living body according to claim 2, wherein the translucent plate has at least a first portion that transmits radiated light based on the first light emitting element protruding outward from the housing. State detection device. The pulse wave sensor is
A housing that houses the light emitting unit and the light receiving unit, and that has an opening at a site through which radiated light from the light emitting unit and reflected light to the light receiving unit pass,
A translucent plate provided at the opening of the housing and transmitting light;
With
In the translucent plate, a first part that transmits radiated light based on the first light emitting element protrudes outward from the second part that transmits radiated light based on the second light emitting element. It has a shape, The biological condition detection apparatus in any one of Claims 2-4 characterized by the above-mentioned.   The biological state detection device according to claim 5 or 6, wherein the casing has a shape in which a peripheral edge of the opening protrudes outward from another portion of the surface on which the opening is formed. .   The living body state detection device according to claim 2, wherein the light receiving unit includes a single light receiving element. The body movement determination means includes
The first body motion determining means for determining that there is a body motion when the amplitude of the body motion detection signal or the difference value of the body motion detection signal is larger than a preset threshold value. The biological state detection apparatus in any one of 1-8. The body movement determination means includes
When the intensity ratio between the maximum peak frequency component of the pulse wave detection signal and the second largest peak frequency component in the frequency region where the fundamental wave of the pulse component can exist is less than or equal to a preset ratio The biological state detection device according to claim 1, further comprising a second body movement determination unit that determines that there is a movement. The body movement determination means includes
The intensity of the peak frequency component of the body motion detection signal in which the intensity of the maximum peak frequency component of the pulse wave detection signal in the frequency region where the fundamental wave of the pulse component can exist has the same frequency as the maximum peak frequency component The biological state detection device according to claim 1, further comprising a third body motion determination unit that determines that there is a body motion in the following cases. The stationarity determining means includes
1st stationarity determination means which determines that there is stationarity when the intensity ratio between the maximum peak frequency component and the second largest peak frequency component of the body motion detection signal is larger than a preset ratio. The biological state detection device according to claim 1. The stationarity determining means includes
The second peak is determined to be stationary when the maximum peak frequency component and the second or third largest peak frequency component of the body motion detection signal are in a relationship in which one is a fundamental wave and the other is a second harmonic. The living body state detection apparatus according to claim 1, further comprising a continuity determination unit. The pulse component extraction means includes
14. A first pulse component extraction unit that extracts a maximum peak frequency component of the pulse wave detection signal as a pulse component when the body movement determination unit determines that there is no body movement. The biological state detection device according to any one of the above. The pulse component extraction means includes
Body motion component specifying means for specifying the fundamental wave and harmonics of the body motion component when the stationarity determining means determines that there is stationarity;
In the frequency region where the fundamental wave of the pulse component can exist, the maximum of the pulse wave detection signal within the frequency range that does not coincide with the fundamental wave and harmonics specified by the body motion component specifying means Second pulse component extraction means for extracting the maximum peak frequency component as a pulse component when the intensity ratio between the peak frequency component and the second largest peak frequency component is greater than a preset ratio;
The biological state detection device according to claim 1, comprising: The pulse component extraction means includes
The maximum peak frequency component of the pulse wave detection signal within a preset search range centered on the frequency of the pulse component specified in the previous measurement, and the body motion component specified by the body motion component specifying means Based on the fundamental wave and the harmonics of, the overlap estimation means for estimating the presence or absence of overlap between the pulse component and the body motion component,
Third pulse component extraction means for extracting, as a pulse component, a maximum peak frequency component of the pulse wave detection signal within the search range when the overlap estimation means estimates that there is no overlap;
The biological state detection device according to claim 15, comprising: The pulse component extraction means includes
When the overlap estimation unit estimates that there is an overlap, the analysis result of the analysis unit within a predetermined range centered on the maximum peak frequency component of the pulse wave detection signal within the search range The biological state detection device according to claim 16, further comprising a fourth pulse component extraction unit that estimates a frequency component corresponding to the pulse component from the pulse rate component. The fourth pulse component extracting means includes
18. The biological state detection device according to claim 17, wherein the analysis results of the pulse wave detection signal and the body motion detection signal are normalized with respect to intensity, and a frequency component having a maximum difference between the two is estimated as a pulse component. . The fourth pulse component extracting means includes
The correlation value between the analysis result of the pulse wave detection signal and the analysis result of the body motion detection signal is calculated for each preset divided section, and the frequency component having the maximum intensity in the divided section where the correlation value is minimum is calculated as a pulse. The biological state detection apparatus according to claim 17, wherein the biological state detection apparatus estimates the component.   The index calculation means which calculates the index which consists of at least one among a pulse rate and a pulse interval based on the pulse component which the said pulse component extraction means extracted. Biological state detection device. The index calculating means includes
Based on the frequency component of the pulse wave detection signal included in a preset frequency range centered on the pulse component extracted by the pulse component extraction means, obtain a weighted average frequency weighted by the intensity of the frequency component, The biological condition detection apparatus according to claim 20, wherein the index is calculated from the weighted average frequency.   The light emission intensity adjusting means for adjusting the light emission intensity at the light emitting unit based on the amplitude of the pulse wave detection signal output from the light receiving unit. Biological state detection device.

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