JP2014195500A - Pulse rate meter and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pulse rate meter, program, and the like for making an apparatus be easily fitted in an appropriate state by accurately determining appropriate pressing force considering an individual difference and storing and displaying holding state identification information when it is determined that the appropriate pressing force is applied.SOLUTION: A pulse rate meter includes: a pulse wave detection unit 10 including a pulse wave sensor 11 for outputting a pulse wave sensor signal and an amplification unit 17 for amplifying the pulse wave sensor signal; a processing unit 100 for calculating pulsation information on the basis of a signal from the pulse wave detection unit 10; a display unit 70 for displaying a processing result of the processing unit 100; a storage unit 90 for storing the processing result of the processing unit 100; and a holding mechanism for holding the pulse rate meter to an analyte. The processing unit 100 determines whether or not pressing force on the analyte at the pulse wave detection unit 10 is appropriate. The storage unit 90 stores holding state identification information for identifying a holding state of the holding mechanism in the case that it is determined that the pressing force is appropriate. The processing unit 100 performs control of displaying the holding state identification information on the display unit 70.

Description

  The present invention relates to a pulse meter, a program, and the like.

  Conventionally, electronic devices such as a pulse meter have been widely used. A pulse meter is a device for detecting a pulsation derived from the heartbeat of a human body, for example, a signal derived from a heartbeat based on a signal from a pulse wave sensor attached to an arm, palm, finger, etc. Is a device for detecting

  For example, a photoelectric sensor is used as the pulse wave sensor. In this case, a method of detecting reflected light or transmitted light of the light irradiated on the living body with the photoelectric sensor can be considered. Depending on the blood flow in the blood vessel, the amount of light absorbed and reflected by the living body differs, so the sensor information (pulse wave sensor signal) detected by the photoelectric sensor is a signal corresponding to the blood flow, etc. By analyzing the signal, it is possible to obtain information on the beat.

  However, it is known that the amplitude of the pulse signal varies depending on the pressure (in this case, an external pressure that is a pressure on the living body from the outside of the living body). An excessive press or an excessive press lowers the pulse signal. Therefore, in order to accurately perform processing based on the pulse signal (for example, calculation of pulsation information), it is necessary to set an appropriate press.

JP 2008-54890 A

  Patent Document 1 proposes a structure that can measure the contact pressure of a biological information detection unit that detects biological information such as a pulse meter. In addition, a method of notifying the user by determining whether or not the contact pressure is an appropriate pressure and displaying the pressure in a graph is also presented.

  However, vital signs such as the pulse are extremely different from person to person, so the value of the appropriate pressure varies from user to user. On the other hand, the technique of Patent Document 1 is represented by physical information such as simple pressure (for example, in units of kPa). Therefore, it is not possible to reliably determine whether or not the processing is appropriate. For example, even if the pressure is within a preset proper pressing range, it is meaningless if the actual pulse signal is too small.

  According to some aspects of the present invention, a pulsometer that facilitates device mounting in an appropriate state by determining appropriate pressing, storing and displaying holding state specifying information when determined as appropriate pressing, and Programs can be provided.

  One embodiment of the present invention includes a pulse wave sensor that outputs a pulse wave sensor signal, a pulse wave detection unit that includes an amplification unit that amplifies the pulse wave sensor signal, and pulsation based on a signal from the pulse wave detection unit A processing unit that calculates information, a display unit that displays a processing result in the processing unit, a storage unit that stores a processing result in the processing unit, and a holding mechanism that holds a pulse meter in the subject. The pulse wave detection unit sets the gain of the AC component signal of the pulse to an appropriate value according to the pulse intensity when determining the appropriate pressure, and the processing unit applies to the subject in the pulse wave detection unit. Whether or not the pressing is an appropriate pressing, and the storage unit determines the holding state of the holding mechanism when the pulse wave detection unit determines that the pressing to the subject is the appropriate pressing. The holding state specifying information to be specified is stored, and the processing unit is configured to store the holding state. Relating to pulse rate monitor for controlling display certain information on the display unit.

  In one aspect of the present invention, it is determined whether or not the pressure on the subject is an appropriate pressure, and information specifying the holding state of the holding mechanism when the pressure is appropriate is stored and displayed as holding state specifying information. To do. Therefore, since the appropriate pressure can be stored and displayed as a holding state instead of physical information such as a pressure value, information on the appropriate pressure can be presented in a form that is easy for the user to understand, and the holding state that realizes the appropriate pressure It becomes easy to reproduce.

  In the aspect of the invention, the processing unit may determine whether or not the pressing is the appropriate pressing based on the pulse wave sensor signal.

  As a result, it is possible to perform appropriate pressure determination in consideration of individual differences for each user.

  In one aspect of the present invention, the processing unit outputs at least one of an AC component signal corresponding to an AC component of the pulse wave sensor signal and a DC component signal corresponding to a DC component of the pulse wave sensor signal. Based on this, it may be determined whether or not the pressing is the proper pressing.

  As a result, it is possible to determine appropriate pressing using at least one of the AC component signal and the DC component signal.

  In the aspect of the invention, the processing unit may determine whether or not the pressing is the appropriate pressing based on a change characteristic of the AC component signal when the pressing is changed. .

  As a result, processing independent of the value itself can be performed, and appropriate pressure determination and the like taking into account individual differences can be performed.

  In the aspect of the invention, the processing unit may determine whether the pressing is the proper pressing based on a change characteristic of the amplitude of the AC component signal when the pressing is changed. Also good.

  As a result, it is possible to determine appropriate pressing based on the change characteristic of the amplitude of the AC component signal.

  In the aspect of the invention, the processing unit may determine whether or not the pressing is the appropriate pressing based on a change characteristic of the DC component signal when the pressing is changed. .

  As a result, processing independent of the value itself can be performed, and appropriate pressure determination and the like taking into account individual differences can be performed.

  In one aspect of the present invention, the processing unit detects an inflection point of the DC component signal based on a change characteristic of the DC component signal when the pressure is changed, and detects the detected inflection. You may determine whether the said press is the said appropriate press based on a point.

  As a result, it is possible to determine appropriate pressure based on the inflection point of the DC component signal.

  In the aspect of the invention, the processing unit may perform control to display an instruction screen for instructing setting of an environment for determination as to whether or not the pressing is the appropriate pressing on the display unit. .

  Thereby, since the setting environment setting instruction can be given, it is possible to improve the accuracy of the appropriate pressure determination.

  In the aspect of the invention, the processing unit may perform control to display a screen for instructing stabilization of body movement of the subject as the instruction screen on the display unit.

  As a result, it is possible to instruct the stabilization of body movement as an instruction to set the determination environment.

  In the aspect of the invention, the processing unit may perform control to display a screen for giving an instruction to the subject to take a given determination posture on the display unit as the instruction screen.

  As a result, an instruction for taking a given determination posture can be given as an instruction for setting the determination environment.

  In the aspect of the invention, the processing unit may perform control to display a screen for instructing the subject to wait for a given time on the display unit as the instruction screen.

  This makes it possible to issue a standby instruction for a given time as an instruction for setting the determination environment.

  In one aspect of the present invention, the processing unit determines whether or not the condition for the determination environment displayed on the instruction screen is satisfied, and when it is determined that the condition is satisfied, It may be determined whether the pressing is the proper pressing.

  As a result, it is possible to determine whether or not the instruction is satisfied after the determination environment setting instruction is issued.

  Moreover, in one aspect of the present invention, the processing unit is for the determination displayed on the instruction screen based on at least one of a body motion detection signal from a body motion sensor and time measurement information from a time measurement unit. It may be determined whether or not the condition of the environment is satisfied, and when it is determined that the condition is satisfied, it may be determined whether or not the pressing is the appropriate pressing.

  This makes it possible to determine whether the conditions for the determination environment are satisfied based on the body motion detection signal and the time measurement information.

  Moreover, in one aspect of the present invention, the processing unit has a holding state specifying information acquisition mode and a pulsation information calculation mode for calculating the pulsation information as processing modes, and is set to the appropriate pressure determination mode. The holding state specifying information is acquired based on a determination result of whether or not the pressing is the appropriate pressing, and the acquired holding state specifying information is stored in the storage unit, and the holding state specifying When the pulsation information calculation mode is set after acquiring the information, the holding state specifying information stored in the storage unit is read, and the read holding state specifying information is displayed on the display unit. Also good.

  Thereby, the holding state specifying information acquired in the holding state specifying information acquisition mode can be displayed in the pulsation information calculation mode, and accurate pulsation information calculation and the like can be performed.

  In the aspect of the invention, the holding mechanism may be in the first to Nth states (N is an integer of 2 or more) in which the pressure on the subject is different in the pulse wave detection unit as the holding state. The processing unit takes at least one of the first to Nth states based on a determination result as to whether or not the pressing in each of the first to Nth states is the appropriate pressure. Information corresponding to one state may be acquired as the holding state specifying information.

  Thereby, in a holding mechanism that takes a plurality of holding states, it is possible to acquire information corresponding to at least one of the plurality of holding states as holding state specifying information.

  In one embodiment of the present invention, the processing unit holds the holding after determining whether or not the pressing in the i-th state (i is an integer satisfying 1 ≦ i ≦ N) is the appropriate pressing. The instruction screen for instructing to change the holding state in the mechanism to a j-th state (j is an integer satisfying 1 ≦ j ≦ N and j ≠ i) in which the pressure is smaller than the i-th state is displayed. You may perform control displayed on a part.

  As a result, the appropriate pressure determination can be performed in the decompression process, so that the accuracy of the appropriate pressure determination can be improved.

  According to another aspect of the present invention, a pulse wave detecting unit having a pulse wave sensor, and determining whether or not the pressure on the subject in the pulse wave detecting unit is an appropriate pressure, and from the pulse wave detecting unit, A processing unit that calculates pulsation information of the subject based on a signal, a display unit that displays a processing result in the processing unit, and a storage unit that stores a processing result in the processing unit, The processing unit relates to a pulse meter that performs control to display on the display unit an instruction screen for instructing setting of an environment for determination as to whether or not the pressing is the appropriate pressing.

  In another aspect of the present invention, an instruction screen for instructing setting of an environment for determination is displayed on the display unit when determining appropriate pressing. Therefore, since it can be expected that an environment suitable for appropriate pressure determination is set, the determination accuracy can be improved.

  Moreover, in one aspect of the present invention, the processing unit determines whether or not the conditions for the determination environment displayed on the instruction screen are satisfied, and the processing when the conditions are determined to be satisfied is determined. Based on the signal from the pulse wave detector, it may be determined whether or not the pressing is the proper pressing.

  Thereby, since the process based on the signal from the pulse wave detection unit when the condition for the determination environment is satisfied can be performed, the determination accuracy can be improved.

  Moreover, the other aspect of this invention is related with the program which functions a computer as said each part.

The basic structural example of the pulse meter of this embodiment. The structural example of the body movement noise reduction part using an adaptive filter. 3A to 3C show examples of a pulse wave detection signal, a body motion detection signal, and a waveform and a frequency spectrum of a signal after body motion noise reduction processing based on the pulse wave detection signal and the body motion detection signal. 4A and 4B show examples of a pulse meter. The detailed structural example of the pulse meter of this embodiment. FIG. 5 is a relationship diagram of pressing and a pulse wave detection signal (AC component signal). The structural example of the band which is a holding mechanism. 8A and 8B are diagrams showing the relationship between the pressure and the AC component signal. FIG. 9A shows an example of the signal value of the AC component signal at a given pressure, and FIG. 9B shows an example of the amplitude value of the AC component signal at the given pressure. FIG. 5 is a relationship diagram of pressing and DC component signals. An example of a signal value of a DC component signal at a given pressure. The flowchart explaining the appropriate press determination process using both AC component signal and DC component signal. The flowchart explaining the process of this embodiment including display control etc. The flowchart explaining a gain value estimation process. FIGS. 15A and 15B are examples of acceleration detection values used for stability determination of body movement, and FIG. 15C is an example of setting an axis of an acceleration sensor. The flowchart explaining the stability determination process of body movement. FIGS. 17A to 17C show examples of screens displayed on the display unit. 18A and 18B show examples of acceleration detection values used for posture determination. 19A and 19B are diagrams schematically illustrating an example of gain adjustment (an example in which gain is increased). FIG. 20 is a diagram schematically illustrating an example of gain adjustment (an example in which gain is decreased). FIG. 21A and FIG. 21B are diagrams illustrating specific examples of gain adjustment. The flowchart explaining an attitude | position determination process. FIG. 23A to FIG. 23C are diagrams for explaining a difference in change characteristics of an AC component signal and a DC component signal between a pressurization process and a decompression process.

  Hereinafter, this embodiment will be described. In addition, this embodiment demonstrated below does not unduly limit the content of this invention described in the claim. In addition, all the configurations described in the present embodiment are not necessarily essential configuration requirements of the present invention.

(Embodiment 1)
1. Configuration Example of Pulse Meter First, a basic configuration example of a pulse meter (electronic device in a broad sense) of the present embodiment will be described with reference to FIG. FIG. 1 shows an example of a pulsometer. The configuration included in the pulsometer of the present embodiment may be simplified or omitted, or may not be an essential component in the pulsometer of the present embodiment. May be included.

  As shown in FIG. 1, the pulse meter of the present embodiment includes a pulse wave detection unit 10, a body motion detection unit 20, a processing unit 100, and a display unit 70. However, the pulse meter is not limited to the configuration shown in FIG. 1, and various modifications such as omission / change of some of these components or addition of other components are possible.

  The pulse wave detection unit 10 outputs a signal based on sensor information (pulse wave sensor signal) of the pulse wave sensor. The pulse wave detection unit 10 can include, for example, a pulse wave sensor 11, a filter processing unit 15, and an A / D conversion unit 16. However, the pulse wave detection unit 10 is not limited to the configuration of FIG. 1, and various components such as omitting some of these components or adding other components (for example, an amplification unit that amplifies a signal, etc.) are included. Variations are possible.

  The pulse wave sensor 11 is a sensor for detecting a pulse wave signal. For example, a photoelectric sensor can be considered. In addition, when using a photoelectric sensor as the pulse wave sensor 11, you may use the sensor comprised so that the signal component of external lights, such as sunlight, may be cut. This can be realized by, for example, a configuration in which a plurality of photodiodes are provided and difference information is obtained by feedback processing using these signals.

  The pulse wave sensor 11 is not limited to a photoelectric sensor, and may be a sensor using ultrasonic waves. In this case, the pulse wave sensor 11 has two piezoelectric elements. One of the piezoelectric elements is excited to transmit an ultrasonic wave into the living body, and the ultrasonic wave reflected by the blood flow of the living body is transmitted to the other. Received by the piezoelectric element. Since the frequency change occurs in the transmitted ultrasound and the received ultrasound due to the Doppler effect of blood flow, a signal corresponding to the blood flow can be obtained in this case as well, and pulsation information can be estimated. . Other sensors may be used as the pulse wave sensor 11.

  The filter processing unit 15 performs high-pass filter processing on the sensor information from the pulse wave sensor 11. Note that the cutoff frequency of the high-pass filter may be obtained from a typical pulse rate. For example, there are very few cases where the pulse rate of a normal person falls below 30 times per minute. In other words, since the frequency of the signal derived from the heartbeat is rarely 0.5 Hz or less, even if the information of the frequency band in this range is cut, the adverse effect on the signal to be acquired should be small. Therefore, about 0.5 Hz may be set as the cutoff frequency. Further, depending on the situation, a different cutoff frequency such as 1 Hz may be set. Furthermore, since it is possible to assume a typical upper limit value for the human pulse rate, the filter processing unit 15 may perform bandpass filter processing instead of high-pass filter processing. The cutoff frequency on the high frequency side can be set freely to some extent, but a value such as 4 Hz may be used.

  The A / D converter 16 performs A / D conversion processing and outputs a digital signal. The process in the filter processing unit 15 described above may be an analog filter process performed before the A / D conversion process, or a digital filter process performed after the A / D conversion process. .

  The body motion detection unit 20 outputs a signal (body motion detection signal) corresponding to the body motion based on the sensor information of various sensors. The body motion detection unit 20 can include, for example, an acceleration sensor 21, a pressure sensor 22, and an A / D conversion unit 26. However, the body motion detection unit 20 may include other sensors (for example, a gyro sensor), an amplification unit that amplifies a signal, and the like. Further, it is not necessary to provide a plurality of types of sensors, and a configuration including one type of sensor may be used.

  The processing unit 100 includes a signal processing unit 110 and a pulsation information calculation unit 120. However, the processing unit 100 is not limited to the configuration in FIG. 1, and various modifications such as omitting some of these components or adding other components are possible. The signal processing unit 110 performs signal processing on the output signal from the pulse wave detection unit and the output signal from the body motion detection unit.

  The signal processing unit 110 can include a pulse wave signal processing unit 111, a body motion signal processing unit 113, and a body motion noise reduction unit 115.

  The pulse wave signal processing unit 111 performs some signal processing on the signal from the pulse wave detection unit 10. Note that various signals based on the pulse wave sensor signal can be considered as the output from the pulse wave detector 10 indicated by D1 in FIG. For example, the calculation of pulsation information, which will be described later, is applied to a pulse wave sensor signal (hereinafter also referred to as a pulse wave detection signal) after the DC component cut, and in the following description, an equivalent signal is referred to as an AC component signal. In many cases, it is assumed that D1 includes a pulse wave sensor signal after high-pass filter processing. However, a signal that has not been subjected to filter processing may be output, or a pulse wave sensor signal after low-pass filter processing may be output depending on circumstances. When D1 includes a plurality of signals (for example, both the pulse wave sensor signal before the high-pass filter processing and the pulse wave sensor signal after the processing), the processing in the pulse wave signal processing unit 111 is included in D1. It may be performed for all of the signals, or may be performed for some of the signals. Various processing contents are also conceivable. For example, an equalizer process for the pulse wave detection signal may be performed, or another process may be performed.

  The body motion signal processing unit 113 performs various signal processes on the body motion detection signal from the body motion detection unit 20. Similar to D1, various signals can be considered as the output from the body motion detection unit 20 indicated by D2. For example, since the example of FIG. 1 includes the acceleration sensor 21 and the pressure sensor 22, the body motion detection signal of D2 includes an acceleration signal and a pressure signal. Since the body motion detection sensor may be another sensor such as a gyro sensor, D2 includes an output signal of a type corresponding to the type of sensor. The processing in the body motion signal processing unit 113 may be performed on all or part of the signals included in D2. For example, the signal included in D2 may be compared to perform a process of determining a signal used in the noise reduction process in the body motion noise reduction unit 115.

  In the processing in the pulse wave signal processing unit 111, a body motion detection signal may be used in addition to the signal from the pulse wave detection unit. Similarly, in the processing in the body motion signal processing unit 113, a signal from the pulse wave detection unit 10 may be used in addition to the body motion detection signal. In addition, a signal after a given process is performed in the pulse wave signal processing unit 111 on the output signal from the pulse wave detection unit 10 may be used for processing in the body motion signal processing unit 113. Or vice versa.

  The body motion noise reduction unit 115 performs a process of reducing noise (body motion noise) caused by body motion from the pulse wave detection signal using the body motion detection signal. A specific example of noise reduction processing using an adaptive filter is shown in FIG. The pulse wave sensor signal acquired from the pulse wave sensor 11 includes a component due to body movement in addition to a component due to heartbeat. The same applies to the pulse wave detection signal (pulse wave sensor signal after the DC component cut) used for the calculation of pulsation information. Of these, components useful for the calculation of pulsation information are components caused by heartbeats, and components caused by body movements hinder the calculation. Therefore, a signal (body motion detection signal) resulting from body motion is acquired using a body motion sensor, and a signal component correlated with the body motion detection signal (referred to as an estimated body motion noise component) is removed from the pulse wave detection signal. By doing so, body motion noise included in the pulse wave detection signal is reduced. However, even if the body motion noise in the pulse wave detection signal and the body motion detection signal from the body motion sensor are signals resulting from the same body motion, the signal level is not necessarily the same. Therefore, the estimated body motion noise component is calculated by performing filter processing in which the filter coefficient is adaptively determined for the body motion detection signal, and the difference between the pulse wave detection signal and the estimated body motion noise component is calculated. To do.

  FIGS. 3A to 3C illustrate the above processing in terms of a frequency spectrum. FIG. 3A and the like show the time-varying waveform of the signal at the top and the frequency spectrum at the bottom. FIG. 3A shows a pulse wave detection signal before body motion noise reduction, and as shown in A1 and A2, two frequencies having large values appear in the spectrum. One of these is caused by heartbeat, and the other is caused by body movement. Note that although there are some frequencies that are higher than A1, they are not considered here because they are high frequency components corresponding to integer multiples of A1 and A2. Hereinafter, high-frequency components are also seen in FIGS. 3B and 3C, but are not considered here as well.

  On the other hand, FIG. 3B shows a body motion detection signal. If there is only one type of body motion that has caused the body motion detection signal, a frequency having a large value as shown in B1 is obtained. One appears. Here, the frequency of B1 corresponds to A2 in FIG. In such a case, the signal shown in FIG. 3C is obtained by taking the difference between the pulse wave detection signal and the estimated body motion noise component by the method shown in FIG. As apparent from the figure, pulse wave detection is performed by subtracting an estimated body motion noise component having a peak B1 due to body motion from a pulse wave detection signal having two peaks A1 and A2 due to heartbeat and body motion. The body motion component (corresponding to A2) in the signal is removed, and as a result, the peak C1 (frequency corresponds to A1) due to the heartbeat remains.

  It is guaranteed that the body motion noise included in the pulse wave detection signal corresponds to the body motion detection signal, and that the body motion detection signal does not contain a signal component that adversely affects the noise reduction processing. In such a situation, since it is not necessary to perform frequency analysis in the body motion noise reduction unit 115, the frequency spectrum shown in the lower part of FIGS. 3 (A) and 3 (B) may not be considered. However, depending on the type of sensor used to acquire the body motion detection signal, there may be a case where the above condition is not satisfied. In that case, for example, the body motion signal processing unit 113 may process the body motion detection signal so as to satisfy the above condition, or a body motion detection signal that does not satisfy the above condition may be processed. Etc. may be excluded from the output. Various methods for determining whether or not the above conditions are satisfied are conceivable. For example, a frequency spectrum obtained by frequency analysis as shown in the lower part of FIGS. 3A and 3B is used. May be.

  The pulsation information calculation unit 120 calculates pulsation information based on the input signal. The pulsation information may be a pulse rate value, for example. For example, the pulsation information calculation unit 120 obtains a spectrum by performing frequency analysis such as FFT on the pulse wave detection signal after the noise reduction processing in the body motion noise reduction unit 115 and obtains a representative frequency in the obtained spectrum. The processing may be performed with the heartbeat frequency as. In that case, a value obtained by multiplying the obtained frequency by 60 is a commonly used pulse rate (heart rate).

  Note that the pulsation information is not limited to the pulse rate, and may be, for example, information indicating the pulse rate (heartbeat frequency, cycle, etc.). Moreover, the information which represents the state of pulsation may be sufficient, for example, the value showing blood flow itself (or its fluctuation | variation) is good also as pulsation information. However, since the relationship between the blood flow rate and the signal value of the pulse wave sensor signal has individual differences for each user, when the blood flow rate or the like is used as pulsation information, correction processing is performed to deal with the individual differences. It is desirable.

  Also, it detects the timing at which a given value (upper peak, lower peak, or a value above a given threshold) appears on the time-varying waveform of the input pulse wave detection signal, and corresponds to the timing interval. The pulsation information may be calculated by obtaining the heartbeat period from the time to be performed. Alternatively, the pulsation information can be calculated by transforming the waveform of the pulse wave detection signal into a rectangular wave and using the rising edge of the rectangular wave. In this case, it is not necessary to perform frequency analysis, which is advantageous in terms of calculation amount and power consumption. However, in this method, since the signal value is used as it is without being converted to the frequency axis, it is necessary to prepare the waveform to some extent. Therefore, it is desirable to perform frequency analysis in a noisy situation or the like.

  The display unit 70 (output unit in a broad sense) is for displaying various display screens used for presenting the calculated pulsation information, and can be realized by, for example, a liquid crystal display or an organic EL display.

  Specific examples of the above-described pulse meter are shown in FIGS. 4 (A) and 4 (B). FIG. 4A shows an example of a wristwatch-type pulse meter. The base unit 400 including the pulse wave sensor 11 and the display unit 70 is attached to the left wrist 200 of the subject (user) by a holding mechanism 300 (for example, a band). FIG. 4B shows an example of a finger wearing type. A pulse wave sensor 11 is provided at the bottom of a ring-shaped guide 302 for insertion into the fingertip of the subject. However, in the case of FIG. 4B, since there is no space to provide the display unit 70, the display unit 70 (and a part corresponding to the processing unit 100 as necessary) is a wired connection connected to the pulse wave sensor 11. It is assumed that it is provided on the other end side of the cable.

  Although the method of the present embodiment described later can be applied to any type of pulse meter, it is more preferable to apply it to a wristwatch type pulse meter (example in FIG. 4A). However, in the example of FIG. 4A, the pulse wave sensor 11 is attached to a portion where it is difficult to acquire a pulse wave sensor signal, such as the outside of the wrist (a portion in contact with the back cover surface of the wristwatch). For this reason, the amplitude of the pulse wave sensor signal output from the pulse wave sensor 11 tends to decrease as a whole. Therefore, it is desirable to perform processing related to accuracy of pulsation information by some method as in the present embodiment described later.

2. As described above, by using a pulse wave sensor such as a photoelectric sensor, a pulse wave sensor signal corresponding to a blood circulation state (for example, blood flow volume) can be acquired. However, when the arm or the like is strongly pressed, the blood flow is reduced by the external pressure on the living body (in the narrow sense, the blood vessel), as can be easily understood from the fact that the blood flow is reduced at the distal side of the compressed portion. Change. In other words, if the external pressure is excessively strong, the signal value of the pulse wave sensor signal is reduced, and the influence of noise is relatively increased (the SN state is deteriorated), which hinders subsequent processing (for example, the pulse). The accuracy of beat information based on the wave sensor signal is reduced).

  Further, even if the external pressure is too small, the signal value of the pulse wave sensor signal becomes small, which is not preferable. As one of the factors, the influence of components caused by veins can be considered. In the pulse wave sensor, both the component caused by the artery and the component caused by the vein are acquired, but the widely used technique is to calculate pulsation information based on the artery component of the sensor. The vein component adversely affects the signal value of the pulse wave sensor signal. That is, when the external pressure is too small, the influence of the vein component appears and the signal value of the pulse wave sensor signal becomes small, which is also not preferable. An example of change characteristics of the AC component signal (pulse wave detection signal) with respect to the external pressure is shown in FIG. As can be seen from FIG. 6, the signal value decreases when the pressure is excessive or excessive.

  The point that blood flow is reduced by applying external pressure is the same for both arteries and veins. However, it is known from the characteristics of living bodies that blood flow is sufficiently reduced with a small external pressure compared to arteries. That is, the pressure at the point where the blood flow in the vein is sufficiently lowered (disappeared in the narrow sense) (hereinafter referred to as “venous vanishing point”) is V1, and the point where the blood flow in the artery is sufficiently lowered (hereinafter referred to as “arterial vanishing point”). When the pressure in the notation is V2, the relationship of V1 <V2 is established. In this case, the case where the external pressure is larger than V2 corresponds to the above-described situation where the external pressure is excessively strong, and the arterial component to be originally acquired has disappeared and a sufficient signal value cannot be obtained. On the other hand, the case where the external pressure is smaller than V1 corresponds to the above-described situation where the external pressure is excessively small, and it is influenced by the venous component, so that a sufficient signal value cannot be obtained.

  That is, by applying an external pressure V satisfying V1 <V <V2 to the subject, it is possible to sufficiently suppress the influence of the venous component and not to lower the blood flow of the arterial component more than necessary. In the present embodiment, V that satisfies the above condition is set as an appropriate pressure. In addition, appropriate press may point out the partial range, specific pressure value, etc. instead of all V which satisfy | fill the said conditions.

  Conventionally, a contact pressure is measured at a portion where biological information is detected using a pressure sensor or the like, and whether the current pressure is an appropriate pressure based on a comparison process between the contact pressure and a given reference value. A method of presenting such information to the user as a graph display is disclosed. However, vital signs such as a pulse are extremely different from person to person, and the above-described proper pressing also takes a different value (range) for each user. Therefore, unless a reference value to be compared with the measured contact pressure is determined for each user, it is not possible to deal with individual differences. However, the conventional method only describes processing based on physical information such as simple pressure. Since it is unlikely that a signal due to individual differences will appear in the physical information of pressure, and a method for setting a reference value corresponding to individual differences is not disclosed, the conventional method discloses a method for dealing with individual differences It will not be done.

  Therefore, in the conventional method, even if the user is instructed to adjust the magnitude of the external pressure by a graph display or the like, the result of following the instruction is in an appropriate state as long as the appropriate pressure as a reference cannot cope with individual differences. It is not known whether this is the case, and this point is considered as the first problem.

  Further, as a second problem of the conventional method, it is mentioned that the correspondence relationship between the contact pressure and the device holding state (wearing state) is not mentioned. In other words, even if the pressure value for proper pressing is known, it is not known how the pressure value can be obtained by attaching the device. If the user wears the device in a certain state and measures the contact pressure, the user can instruct to increase or decrease the pressure (for example, whether the band is tightened or loosened). The instruction cannot be started. Therefore, when the device is remounted, it is necessary to adjust the mounting state every time.

  Therefore, the present applicant proposes a method for determining proper pressing based on the pulse wave sensor signal. Since the characteristics of the pulse wave sensor signal appear for each user, it is possible to cope with individual differences as long as the determination is based on the pulse wave sensor signal. Furthermore, although the same user can change the range of appropriate pressing due to changes in physical condition or the like, the method of this embodiment can cope with such changes.

  However, as described above, since the signal value of the pulse wave sensor signal is different for each user, there are users who have a relatively large signal value and a small user at the appropriate pressure. Therefore, even if a signal value at a certain pressure is used alone, it is difficult to determine whether the pressure is an appropriate pressure. Therefore, in the present embodiment, it is assumed that the pulse wave sensor signal is acquired while changing the pressure, and whether or not the pressure is appropriate is determined by using the change characteristic of the pulse wave sensor signal with respect to the pressure.

  Moreover, in this embodiment, when it determines whether it is in an appropriate press, the holding | maintenance state specific information at the time of determining with an appropriate press is memorize | stored. This is, for example, information that an appropriate pressure can be applied in the case of this user if the device is mounted using what band hole. In this way, an appropriate wearing state can be defined not by the value of pressing but by the tightening degree of the band, etc., so that it is intuitive and easy for the user to understand. Further, if the stored holding state specifying information is displayed, the user can easily reproduce the holding state that realizes the appropriate pressing. That is, adjustment or the like is not necessary at the time of remounting, which is advantageous from the viewpoint of convenience.

  The conventional technique also discloses a technique of automatically pressurizing and depressurizing using a pump or the like. This method is preferable in that it does not require manual adjustment of the user's wearing state, but when it is assumed to be used during daily life or exercise like a wrist-worn device, considering the size, power consumption, etc. Such a technique is not considered here because it is not realistic. That is, in the present embodiment, the pressure is changed in the appropriate pressure determination as described above, but it is assumed that the pressure change is performed by the user's hand. Therefore, interaction with the user using an interface such as a display unit is important in order for the system to instruct the user of an appropriate pressure change.

  Hereinafter, after describing an example of the system configuration of the pulse meter, a method for determining an appropriate pressure based on the pulse wave sensor signal will be described. Finally, a display control method that assumes user interaction will be described.

  Strictly speaking, it is known that the blood circulation state depends not only on the external pressure but also on the internal pressure which is the pressure inside the blood vessel. However, in the present embodiment, as will be described later, by performing control to display an appropriate instruction screen, fluctuations in the internal pressure are suppressed as much as possible, and processing such as determining appropriate pressure is performed by changing the external pressure in that state. Therefore, in the method of the present embodiment, it is an exceptional situation that the internal pressure changes greatly, and such a case is not particularly considered. Therefore, not only the term “press” means an external pressure but also the term “pressure” or “contact pressure” is used unless otherwise specified.

3. System Configuration Example FIG. 5 shows a system configuration example of the pulse meter according to the present embodiment. The pulse meter includes a pulse wave detection unit 10, a body motion detection unit 20, a processing unit 100, a display unit 70, an external I / F unit 80, and a storage unit 90. However, the pulse meter is not limited to the configuration of FIG. 5, and various modifications such as omitting some of these components or adding other components are possible. For example, in this embodiment, reduction of body movement noise is not essential, and the body movement noise reduction unit 115 of the processing unit 100 may be omitted. As shown in FIG. 4 (A), the overall configuration of the pulse meter may include a holding mechanism 300 and a base portion 400, and each portion shown in FIG. 5 is the base portion of FIG. 4 (A). 400 is assumed to be included.

  The pulse wave detection unit 10 includes a pulse wave sensor 11, filter processing units 15-1 and 15-2, A / D conversion units 16-1 and 16-2, and an amplification unit 17. However, the pulse wave detection unit 10 is not limited to the configuration in FIG. 5, and various modifications such as omitting some of these components or adding other components are possible.

  The pulse wave sensor 11 uses a photoelectric sensor or the like as described above with reference to FIG. The filter processing unit 15-1 is realized by a high-pass filter that performs high-pass filter processing in the present embodiment, and the filter processing unit 15-2 is realized by a low-pass filter that performs low-pass filter processing in the present embodiment. That is, the output of the filter processing unit 15-1 is an AC component signal that is a high frequency component of the pulse wave sensor signal, and the output of the filter processing unit 15-2 is a DC component signal that is a low frequency component of the pulse wave sensor signal. It is. The amplifying unit 17 can adjust the sensitivity of the pulse signal by adjusting the gain GN. In the present embodiment, the pulse wave detection unit 10 includes an A / D conversion unit 16-1 and an A / D conversion unit 16-2, and converts each input analog signal into a digital signal and outputs the digital signal.

  As shown in FIG. 5, the pulse wave sensor 11 is connected to the filter processing unit 15-1 and the filter processing unit 15-2. The filter processing unit 15-1 is connected to the amplification unit 17. The amplification unit 17 is connected to the A / D conversion unit 16-1. The A / D conversion unit 16-1 is connected to the body motion noise reduction unit 115 and an appropriate pressure determination unit 119 described later. The filter processing unit 15-2 is connected to the A / D conversion unit 16-2. The A / D conversion unit 16-2 is connected to the appropriate pressure determination unit 119.

  The pulse wave detection unit 10 may omit the filter processing unit 15-2. In that case, the output of the A / D converter 16-2 is a signal including both the high frequency component and the low frequency component of the pulse wave sensor signal. In addition, various modifications can be made to the connection of each unit included in the pulse wave detection unit 10.

  The body motion detection unit 20 includes an acceleration sensor 21 and an A / D conversion unit 26. The acceleration sensor 21 is connected to the A / D conversion unit 26, and the A / D conversion unit 26 is connected to the body movement noise reduction unit 115 and the appropriate pressure determination unit 119. The body motion detection unit 20 only needs to have a sensor for detecting body motion, and the acceleration sensor 21 may be changed to another sensor, or may have a plurality of sensors.

  The processing unit 100 includes a signal processing unit 110, a pulsation information calculation unit 120, a display control unit 130, a time measurement unit 140, and an amplification unit control unit 150. The signal processing unit 110 reduces body motion noise. Part 115 and appropriate pressure determination part 119. However, the processing unit 100 and the signal processing unit 110 are not limited to the configuration in FIG. 5, and some of these components (for example, the body motion noise reduction unit 115) are omitted or other components are added. Various modifications of the above are possible.

  The appropriate pressing determination unit 119 is configured to perform pressing corresponding to the signal acquisition timing based on at least one of the AC component signal from the A / D conversion unit 16-1 and the DC component signal from the A / D conversion unit 16-2. It is determined whether or not the pressure is proper. At this time, a body motion detection signal from the body motion detection unit 20, time measurement information from the time measurement unit 140, or the like may be used. Further, the holding state specifying information for specifying the holding state of the holding mechanism 300 when it is determined that the pressure is appropriate based on the information from the external I / F unit 80 is acquired, and the acquired holding state specifying information is stored. Output to the unit 90 and the display control unit 130. Details of processing in the appropriate pressure determination unit 119 will be described later.

  The body motion noise reduction unit 115 performs body motion noise reduction processing on the AC component signal from the A / D conversion unit 16-1 based on the body motion detection signal from the body motion detection unit 20. The processing content of the body motion noise reduction unit 115 is the same as that described above with reference to FIG. The processing in the pulsation information calculation unit 120 is also as described above.

  The display control unit 130 performs control for display on the display unit 70. For example, in the determination by the appropriate pressure determination unit 119, it is necessary to change the pressure, but control is performed to display an instruction screen for instructing the user so that an appropriate pressure change can be realized. Moreover, you may perform control which displays the instruction | indication screen which performs the instruction | indication which sets the environment for determination whether it is an appropriate press. In addition, display control of the pulsation information calculated by the pulsation information calculation unit 120 is also performed. Details will be described later.

  The time measurement unit 140 performs time measurement processing. For example, it is possible to have a timer that acquires time information such as a time stamp at a given interval and measure the time from the difference of the acquired time information.

  The amplification unit control unit 150 can adjust the sensitivity of the pulse signal by controlling the gain GN in the amplification unit 17.

  The display unit 70 displays various types of information according to the control contents in the display control unit 130. The external I / F unit 80 serves as an interface with the outside, and may be an operation unit having various buttons, a GUI, and the like for a user to perform various operations of the pulse meter in a narrow sense. The storage unit 90 serves as a work area for the processing unit 100 and the like, and its function can be realized by a memory such as a RAM, an HDD (hard disk drive), or the like. The storage unit 90 stores various types of information, but particularly stores the holding state specifying information acquired by the appropriate pressure determination unit 119.

4). 4.1 Appropriate pressure determination based on pulse wave sensor signal 4.1 Determination of appropriate pressure Next, a method for determining appropriate pressure based on a pulse wave sensor signal will be described. As described above, since the signal value of the pulse wave sensor signal varies depending on the user, there are users who have a relatively large signal value and users who have a relatively small signal value when the pressure is appropriate. Therefore, even if only the signal value at the time of a given press is acquired, it is difficult to determine whether the press is an appropriate press based on the signal value. For example, a threshold value that can be used universally for a plurality of users is set even if it is determined whether or not the pressure is an appropriate pressure by comparing the signal value with a given threshold value. Is difficult.

  Therefore, in this embodiment, the pressure on the living body is changed, and the appropriate pressure is determined based on the change characteristic of the pulse wave sensor signal with respect to the pressure change. This is because there are individual differences in the magnitude of the signal value, but the change characteristics of the pulse wave sensor signal have the same tendency for all users. For example, when considering discrete pressure changes, different first to Mth presses are sequentially applied to the living body, and pulse wave sensor signals at each press are acquired. And what is necessary is just to determine which press is an appropriate press among the 1st-Mth presses based on the acquired 1st-Mth pulse wave sensor signal.

  In addition, since the appropriate pressure has a certain range in view of the characteristics of the living body (the range satisfying V1 <V <V2 described above), the pressure determined as the appropriate pressure by the present embodiment is limited to one pressure value. Instead, it may have multiple values or be represented by a given range.

  In the following description, the pulse meter is a wristwatch type device having a band as the holding mechanism 300 as shown in FIG. 4 (A), and the band is provided with a plurality of holes as shown in FIG. It is assumed that the pressure can be changed depending on which hole is used for holding. However, the configuration of the holding mechanism 300 is not limited to this.

  In addition, although the pressure change is performed by the user, display control such as displaying an instruction screen on the display unit 70 is performed in order to realize it. Specific interaction based on display control or the like will be described later, and here, a determination process based on the acquired pulse wave sensor signal will be described on the assumption that the pressure change is appropriately performed. Further, in order to improve the determination accuracy, it is necessary to set an appropriate determination environment. The environment setting is also performed by display control of an instruction screen or the like, and details will be described later. Here, as in the case of the pressure change, the description will be made on the assumption that an appropriate determination environment is set.

  As described above, in the present embodiment, the proper pressing is performed in association with the holding state of the holding mechanism 300 instead of the physical quantity in units such as kPa. Therefore, in the following description, in order to simplify the description, the appropriate pressure is determined by changing the pressure, but changing the pressure corresponds to changing the holding state in the holding mechanism 300. And determining appropriate press is equivalent to determining the holding state which implement | achieves proper press.

4.2 Appropriate pressure determination based on AC component signal Determination based on the AC component signal corresponding to the AC component of the pulse wave sensor signal will be described. FIGS. 8A and 8B show the change characteristics of the signal value of the AC component signal with respect to the pressure change. However, FIG. 8A is a diagram for explaining a general change tendency of the AC component signal with respect to pressing. The horizontal axes of FIGS. 8A and 8B represent time, and are graphs in the pressure-reducing direction in which the pressure is lowered with time, as is apparent from the time change of the pressure.

  As shown in FIG. 8A, the amplitude of the AC component signal becomes a small value when the pressure is large, but the amplitude value becomes larger as the pressure is lowered. When the pressure becomes smaller than a given value, the amplitude value starts to decrease. In consideration of the fact that the AC component signal is a signal resulting from the heartbeat and is used for the calculation of pulsation information, a pressing with a large amplitude value of the AC component signal may be determined as an appropriate pressing. For example, in the case of FIG. 8A, the range indicated by E1 is the appropriate pressure.

  That is, when an AC component signal is used, an amplitude value at each press may be calculated, and a press at which the calculated amplitude value increases may be set as an appropriate press. Specific examples are shown in FIGS. 9A and 9B. FIG. 9A shows the time change of the AC component signal when the band hole position is set to a given position, and the unit of the horizontal axis is seconds. The first half of FIG. 9A (a period of about 0 to 10 seconds) is a timing when the band hole position is set, and a period in which the time elapsed from the timing is short. In this period, the signal value of the AC component signal Is not stable, the amplitude value is not calculated. That is, the amplitude value is determined based on a signal value (for example, a signal value in the period F1 in FIG. 9A) after a given time has elapsed after the band is attached.

  Here, the amplitude value may be calculated based on the peak, and either the upper peak or the lower peak may be used. Here, the amplitude value is calculated from both of them. Specifically, the maximum value (upper peak) and the minimum value (lower peak) in one cycle of the AC component signal (corresponding to one beat of the heart) are detected, and the difference value (Peak) between the maximum value and the minimum value is detected. to peak) is an amplitude value in the period. As indicated by F1 in FIG. 9A, it is assumed that the calculation period of the amplitude value is longer than one cycle of the AC component signal, and thus a plurality of difference values are acquired in the calculation period. FIG. 9B is an example of the time variation of the difference value, in which the difference values acquired once for each cycle of the pulsation are arranged in the order of acquisition (the horizontal axis represents the order of acquisition and the second Etc.) In the present embodiment, the average value of the plurality of difference values in the amplitude value calculation period (F1) may be the amplitude value at the set band hole position (and the corresponding press).

  The average value may be a simple average value or a trim average value that excludes extremely large (or small) data in the average value calculation. If the trim average value is used, the exclusion range may be set based on the standard deviation σ, for example, 3σ may be used.

  With the above processing, the amplitude value of the AC component signal at a given pressure (band hole position) can be calculated. In the determination of proper pressing, the amplitude value at each pressing may be obtained, and the pressing with the maximum amplitude value may be determined as the proper pressing.

4.3 Appropriate pressure determination based on DC component signal Determination based on the DC component signal corresponding to the DC component of the pulse wave sensor signal will be described. FIG. 10 shows the change characteristic of the signal value of the DC component signal with respect to the pressure change. However, FIG. 10 is a diagram for explaining a general change tendency of the DC component signal with respect to pressing. Unlike FIG. 8A and FIG. 8B, the horizontal axis of FIG. 10 represents pressing.

  As shown in FIG. 10, in the change characteristic curve of the DC component signal with respect to the pressure change, both the pressure corresponding to the venous vanishing point and the pressure corresponding to the arterial vanishing point are inflection points. That is, by detecting the inflection point of the DC component signal, it is possible to detect the pressure corresponding to the venous vanishing point and the pressure corresponding to the arterial vanishing point. As described above, the appropriate pressure may be any pressure that is larger than the pressure at the venous vanishing point and smaller than the pressure at the arterial vanishing point. Moreover, one pressure value among the pressure ranges satisfying the above conditions may be set as the appropriate pressure, and for example, an average value of the pressure at the venous vanishing point and the pressure at the arterial vanishing point may be set as the appropriate pressure.

  Various methods for detecting the inflection point of the change characteristic curve of the DC component signal are conceivable. For example, as shown in FIG. 8B, if the pressure changes with time, the DC component signal corresponding to the time change curve (that is, the horizontal axis is time and the vertical axis is DC). Since the graph indicating the signal value of the component signal also represents the change characteristic of the DC component signal corresponding to the pressure change, the inflection point of this curve may be detected. With this method, the signal value of the DC component signal acquired at each time can be used as it is, and thus there is an advantage that no preprocessing or the like is required.

  On the other hand, in the above-mentioned time change curve, the horizontal axis of the graph is only the time and is not the press, and therefore, when the change in the horizontal axis direction is considered, it does not correspond to the linear change of the press. For example, when pressing between times T1 and T2 is considered, it is unlikely that the pressing changes with a certain inclination, and the pressing during the period remains unchanged, or T1 to T3 (T3 <T2 ), It is conceivable that the first pressing causes an extreme change that becomes the second pressing at T3 to T2. In other words, not the time change curve but the pressure change curve as shown in FIG. 10 (a graph in which the horizontal axis is the press and the vertical axis is the signal value of the DC component signal) shows the change characteristics with respect to the press more markedly. It is expected. Also, as mentioned in the explanation of the AC component signal, it is considered that the signal value is not stable for a given time after the band is attached, but such an unstable signal value appears as it is in the time change curve. May adversely affect processing.

  Therefore, in this embodiment, when a given pressure is set, one representative value is calculated based on the DC component signal at the pressure. By performing this process for a plurality of presses, a graph (corresponding press change curve) representing the correspondence between the press and the DC component signal can be acquired, so if an inflection point in the acquired graph is detected. Good.

  A method for calculating a representative value when a given pressure is set will be described with reference to FIG. FIG. 11 shows a time change of the DC component signal when the band hole position is set to a given position. Similarly to FIG. 9A, the first half of FIG. 11 is a timing when the band hole position is set and a period in which the time elapses from the timing is short, and the signal value of the DC component signal is not stable in this period. The representative value is not calculated, and the subsequent period indicated by G1 is used. Various methods for calculating the representative value are conceivable. For example, an average value of the signal values of the DC component signal in the calculation section (G1 in FIG. 11) may be taken. Similar to the processing with the AC component signal, the average value may be a simple average value or may be a trim average value that excludes extremely large (or small) data in the average value calculation. In this way, the pressure change curve of the DC component signal can be obtained by obtaining the representative value at each press.

  The detection of inflection points from curves is a mathematically important field, and there are many conventional examples of inflection point detection in computer systems and the like. Since any method can be used in the present embodiment, detailed description of the inflection point detection method is omitted.

4.4 Appropriate pressure determination based on the AC component signal and the DC component signal The appropriate pressure determination of the present embodiment uses not only processing based on one of the AC component signal and the DC component signal but also both signals. May be.

  A specific example is shown in the flowchart of FIG. When this process is started, first, a pressure VA having the maximum amplitude value is obtained based on the AC component signal (S101). Then, the inflection point of the DC component signal is detected to obtain the pressure VD1 at the venous vanishing point and the pressure VD2 at the arterial vanishing point (S102). The specific processing of S101 and S102 is as described above.

  Thereafter, it is determined whether the relationship of VD1 <VA <VD2 is established (S103). If Yes in S103, since VA is included in the appropriate range obtained from the DC component signal, the reliability of VA is As what is ensured, VA is set as an appropriate press (S104). On the other hand, in the case of No in S103, there remains a question about the reliability of the VA, and therefore the appropriate pressure is determined based on VD1 and VD2 obtained from the DC component signal (S105). Specifically, an average value of VD1 and VD2 may be set as an appropriate pressure.

  As a result, it is possible to determine the appropriate pressure based on both the AC component signal and the DC component signal, and it can be expected to improve the accuracy of the determined appropriate pressure. Further, the processing based on both the AC component signal and the DC component signal is not limited to that shown in the flowchart of FIG. 12, and other processing may be performed.

5. Display control method The pressure change in the appropriate pressure determination is performed by adjustment of the holding mechanism 300 by the user (for example, adjustment of the band hole position). However, if the user grasps all the procedures for determining the appropriate pressure, the user burden is large and not preferable. Therefore, in this embodiment, an interaction between the pulse meter and the user is performed using an interface such as the display unit 70, and the user side is reduced by giving appropriate instructions from the system side (pulse meter side). To do.

  In addition, if the signal value fluctuates due to a factor other than the pressure change at the time of determining the appropriate pressure, the determination accuracy is not preferable. Therefore, in order to suppress undesired fluctuations in the signal value, it is determined whether or not a given condition for determination is satisfied, and an appropriate pressure determination is performed when it is determined that the condition is satisfied. Also at this time, if the condition is not satisfied, some instruction is required for the user, so an interface such as the display unit 70 may be used.

  Hereinafter, the user-system interaction in the present embodiment, display control performed at that time, and the like will be described using a typical processing flow in appropriate pressure determination.

  FIG. 13 shows a flowchart for explaining the process of determining proper pressing. When this processing is started, first, gain value estimation processing (S201) is performed. The gain value estimation process will be described with reference to FIG. In the gain value estimation process, first, as a condition for the determination environment, it is determined whether or not the body movement is stable (S301). This is because, when the body movement is not stable, a component (body movement noise) due to the body movement is included in the AC component signal, which hinders proper pressure determination. The process of S301 may be performed based on a body motion detection signal from a body motion sensor. The body motion sensor is, for example, the acceleration sensor 21, and the body motion detection signal is an acceleration detection value.

  FIG. 15B shows a specific example of the acceleration detection value. As is clear from FIG. 15B, the magnitude of the acceleration detection value becomes very large when there is body movement, compared to when there is no body movement. Therefore, it may be determined that the body movement is not stable when the acceleration detection value is large, and that the body movement is stable when the acceleration detection value is small.

  The acceleration sensor here is a three-axis acceleration sensor, and the axis direction is as shown in FIG. As shown in FIG. 15C, when a plane including a watch face part (corresponding to the display unit 70 in the pulse meter) is considered, it is included in the plane, and the 12 o'clock direction of the watch is the Y axis. The 3 o'clock direction of the watch is the X axis. The Z axis is orthogonal to a plane including the X axis and the Y axis, and is an axis in a direction toward the wrist side of the subject with respect to the dial portion. However, the direction of the axis is not limited to this.

  Here, the triaxial synthetic acceleration shown in FIG. 15A is calculated, and whether or not the body motion is stable is determined based on a comparison process between the calculated magnitude of the synthetic acceleration and a given threshold value. I do. A flowchart is shown in FIG. As the triaxial synthetic acceleration, the square root of the sum of squares of each axis is obtained (S401), and the obtained triaxial synthetic acceleration is compared with the body motion stability threshold (S402). If the three-axis composite acceleration is greater than the body motion stabilization threshold, it is determined that there is body motion (not stable) (S403), and if not, it is determined that there is no body motion (stable). (S404).

  Next, when it is determined that the body movement is not stable by the above processing (No in S301), the body movement is awaited. At that time, it is considered that the condition of the environment for determination can be efficiently realized by instructing the user to stabilize the body movement from the system side. Therefore, control is performed to display an instruction screen for instructing stabilization of body movement on the display unit 70 (S302).

  In the case of Yes in S301, it is determined whether there is any abnormality in the user's posture as the second determination environment condition (S303). Here, in a narrow sense, the posture refers to a posture determined by the relationship between the attachment site of the pulse wave sensor 11 (here, the wrist is assumed) and the height of the heart. That is, when the posture changes, the magnitude of the hydrocephalic pressure applied to the blood vessel changes, and thus the blood flow changes, and posture determination is performed as a condition for suppressing a decrease in accuracy of proper press determination due to this.

  As an example, a typical posture when the user looks at the dial part of the wristwatch may be set as a reference posture, and a posture in which the height relationship between the wrist and the heart is greatly different may be set as an abnormal posture. Examples of acceleration detection values at this time are shown in FIGS. 17 (A) and 17 (B). FIGS. 17A and 17B are merely different diagrams due to the problem of visibility of the graph, and the X axis, Y axis, and Z axis values are acquired from the same acceleration sensor 21. FIG. It is a thing. Since the axis of the acceleration sensor here is the one shown in FIG. 15C, the acceleration detection value of each axis (assuming that the body movement is small, the gravitational acceleration component acting on each axis is the main. The typical range in the standard posture can be specified to some extent. For example, it is conceivable that the plane including the dial portion is close to the horizontal plane, and the direction of gravity is close to the Z axis. In this case, the X-axis and Y-axis values are close to 0, and the Z-axis value is close to 1G. Therefore, based on these values, an appropriate range of values for each axis in the reference posture is set, and the posture is determined based on whether or not the acceleration detection value is within the appropriate range. As shown in FIGS. 17A and 17B, the value of each axis is out of the appropriate range in the abnormal posture.

  A flowchart is shown in FIG. When this processing is started, first, acceleration detection values on the X, Y, and Z axes are measured (S501). Then, a comparison process between the appropriate range of each axis set in advance and the acceleration detection value measured in S401 is performed (S502). If the acceleration detection values of all the axes are within the appropriate range, it is determined that the posture is normal (S503). Otherwise, the posture is determined to be abnormal (S504).

  In addition, since it is assumed that the part beyond the elbow of the arm is maintained in a state close to the horizontal, the appropriate range of the X axis is a narrow range including 0G (for example, −0.1 to +0. 1G). On the other hand, there is a high possibility that the wrist angle varies from person to person, and it is desirable to set an appropriate range wider than the X axis while the Y axis is 0G and the Z axis is 1G. However, the appropriate range is not limited to the numerical values shown in S502 of FIG.

  Next, when it is determined that the posture is abnormal (No in S303) by the above processing, the routine waits for the posture to become normal. In this case, display control of an instruction screen for instructing the user to take a normal posture may be performed similarly to the stabilization of body movement. (S304) In this case, it is desirable to display an instruction screen that makes it clear what the normal posture is in consideration of user convenience and the like. As shown in S304 of FIG. 14, it may be instructed by text, or may be instructed by displaying a diagram if there is no problem in the resolution of the display unit 70 or the like.

  In the case of Yes in S303, it is determined whether a certain time has elapsed since the band was attached as the condition for the third determination environment (S305). When the holding mechanism 300 is realized by a band using a hole or the like, it is necessary to tighten the band once more than at the time of mounting with the band hole for mounting with a given band hole. Therefore, as shown in FIG. 9 (A) or FIG. 11, the AC component signal and the DC component signal at the time of wearing fluctuate greatly, which is not preferable for proper pressure determination, and the signal value is not stable for a certain time thereafter. Therefore, in order to perform an appropriate appropriate pressure determination, such an unstable signal value may be excluded from the processing. Specifically, the process waits for a certain period of time without being mounted, and starts the process after the certain period of time has elapsed.

  In S305, for example, it may be determined whether a given time has elapsed based on time measurement information from the time measurement unit 140 realized by a timer or the like. Next, when it is determined that the given time has not elapsed (No in S305), control is performed to display an instruction screen for instructing the user to wait (S306).

  When it is determined Yes in S305, the determination environment condition is satisfied, and therefore the gain GN is set.

  The setting of the gain GN will be described with reference to FIGS.

  The amplification unit control unit 150 adjusts (controls) the sensitivity of the pulse signal AC based on the degree of the ratio of the amplitude value of the sensor signal dx to the predetermined allowable amplitude value (dynamic range). The amplitude value of the sensor signal dx in a predetermined period (for example, a period of 0 to 4 seconds after the start of measurement) is determined by a difference value between the maximum value and the minimum value in the predetermined period.

  The predetermined allowable amplitude value corresponds to a dynamic range that defines a range that the value of the sensor signal dx can take, for example. The sensitivity of the pulse signal is determined according to the gain GN of the amplifying unit 17. That is, the sensitivity of the pulse signal can be adjusted by adjusting the gain GN of the amplification unit 17.

  The amplification unit control unit 150 detects the ratio of the amplitude of the sensor signal dx to the allowable amplitude value (dynamic range). Therefore, for example, the gain GN of the amplifying unit 17 can be set so that the amplitude of the sensor signal dx is as large as possible (for example, maximum) within the allowable amplitude value (dynamic range). . Therefore, the gain GN of the amplifying unit 17 can be set to an appropriate gain GN corresponding to the initial state of the measurement target (for example, as large as possible).

  FIG. 19A and FIG. 19B are diagrams schematically illustrating an example of gain adjustment (an example in which the gain GN is increased). In the example of FIGS. 19A and 19B, the measurement is started with a set value of 4 (initial value). In this case, the gain GN of the amplification unit 17 is 16. In addition, the amplitude value of the sensor signal dx in a predetermined period (for example, a period of 0 second to 4 seconds after the start of measurement) is Q1a. The amplitude value Q1a of the sensor signal dx is determined by the difference between the maximum value M2 and the minimum value M1. The allowable amplitude value (dynamic range) that can be taken by the sensor signal dx is DL. The lower limit value of the allowable amplitude value DL is LL, and the upper limit value is LU (specifically, 512).

  Here, the amplification unit control unit 150 converts the amplitude value Q1a of the sensor signal dx into, for example, five amplitude threshold values (first amplitude threshold value to fifth amplitude threshold value having values of 16, 32, 64, 128, and 256). Thus, the degree of the ratio of the amplitude value Q1a of the sensor signal dx to the allowable amplitude value DL is determined.

  Here, the midpoint value of the allowable amplitude value of the sensor signal dx is set to 0, and the upper limit value is set to 512. In addition, when the amplitude value (Q1a) of the sensor signal dx in the predetermined period is x and the amplitude threshold value is y, the amplification unit controller 150 corresponds to the minimum y that satisfies x <y. The amplitude threshold value to be specified is specified from the first amplitude value to the fifth amplitude value.

  As a result, in the example of FIG. 19A, the first amplitude threshold (value 16) is specified. The amplification unit control unit 150 determines a value of a set value (here, m) according to the specified amplitude threshold value. In the example of FIG. 19A, the set value m = 9 is determined.

  The timing of this adjustment is, for example, a point in time when the above-described predetermined period (a period of 0 second to 4 seconds after the start of measurement) ends. In the example of FIG. 19A, the gain GN is adjusted to 512. This corresponds to 32 times the gain GN when the set value m = 4.

  In the example of FIG. 19B, the amplitude value of the sensor signal dx is Q1b. In this case, the fifth amplitude threshold (value 256) is selected as the amplitude threshold. In this case, the set value m is determined to be 5. As a result, the gain GN of the amplifying unit 17 is adjusted to 32. This corresponds to twice the gain GN when the set value m = 4.

  Thus, after the measurement is started, the gain GN of the amplifying unit 17 is adjusted to an appropriate value.

  FIG. 20 is a diagram schematically illustrating an example of gain adjustment (an example in which the gain GN is decreased). In the example of FIG. 20, the measurement is started with a set value of 4 (initial value). In this case, the gain GN of the amplification unit 17 is 16. In addition, the amplitude value of the sensor signal dx in a predetermined period (for example, a period of 0 second to 4 seconds after the start of measurement) is Q1a. The amplitude value Q1a of the sensor signal dx is determined by the difference between the maximum value M2 and the minimum value M1. The allowable amplitude value (dynamic range) that can be taken by the sensor signal dx is DL. The lower limit value of the allowable amplitude value DL is LL, and the upper limit value is LU (specifically, 512).

  When the gain GN of the amplifying unit 17 is decreased, the amplifying unit control unit 150 identifies the value of the set value m. In order to determine how much to decrease the gain GN, the amplification unit control unit 150 detects, for example, whether the amplitude value of the sensor signal dx exceeds a predetermined allowable amplitude value DL (LL, LU). Then, the sensitivity adjustment of the pulse signal is executed based on the detection result. Note that a phenomenon in which the amplitude value of the sensor signal dx exceeds a predetermined allowable amplitude value (dynamic range) may be referred to as “shaking out”.

  For example, the amplifying unit control unit 150 determines whether or not the amplitude value of the sensor signal dx has exceeded a predetermined allowable amplitude value DL in a predetermined period (for example, a period of 0 second to 4 seconds after the start of measurement). Detection may be performed and the sensitivity of the pulse signal may be adjusted based on the presence or absence of shaking. A specific example of sensitivity adjustment will be described later with reference to FIG.

  When shakeout occurs, the value of the sensor signal dx output from the amplifying unit 17 is saturated. The fact that the oscillation is lost means that an excessive signal exceeding a predetermined amplitude allowable value (dynamic range) is input to the amplifying unit 17. In the example of FIG.

  In this case, the amplification unit control unit 150 can reduce the gain GN of the amplification unit 17 to prevent the shakeout from occurring.

  It is considered that the greater the degree of disturbance of the signal input to the amplifying unit 17, the higher the possibility of increasing the number of shakes. Therefore, the amplification unit control unit 150 can adjust the gain GN of the amplification unit 17 based on the number of shakes (a process of appropriately reducing the gain GN), thereby preventing the shakes from occurring.

  In the example of FIG. 20, the swing-out on the upper limit LU side is continued three times (time t10 to t11, time t12 to t13, time t14 to t15), and the swing-off on the lower limit value LL side is also continued three times ( Time t11 to t12, time t13 to t14, time t15 to t16). In this case, the number of shakeouts is 3.

  In addition, when the amplitude value of the sensor signal dx exceeds the predetermined allowable amplitude value during the predetermined period, the amplifying unit control unit 150 sets the upper limit value LU of the predetermined allowable amplitude value as the amplitude value of the sensor signal dx. The sensitivity of the pulse signal may be adjusted based on whether it exceeds or exceeds a lower limit LL of a predetermined allowable amplitude value.

  Here, the phenomenon in which the amplitude value of the sensor signal dx exceeds the upper limit LU of the predetermined allowable amplitude value may be referred to as “positive swing out”, and the amplitude value of the sensor signal dx is the predetermined allowable amplitude value. A phenomenon that exceeds the lower limit LL of “N” may be referred to as “negative swing out”.

  In the example of FIG. 20, the forward swing is generated at time t10 to t11, time t12 to t13, and time t14 to t15. In addition, the negative swing occurs at times t11 to t12, times t13 to t14, and times t15 to t16.

  Next, a specific example of gain setting will be described with reference to FIG. FIGS. 21A and 21B are diagrams illustrating specific examples of gain setting.

  FIG. 21A shows a specific example when the gain GN is increased. In this example, the allowable amplitude value (dynamic range) of the sensor signal dx is set to 0 to 1023 (for 10 bits). In the example of FIG. 21A, the amplitude threshold value, the set value, the gain GN, and the expected amplitude upper limit that are used are shown for each of Case 1 to Case 5.

  In the example of FIG. 21A, the midpoint value of the allowable amplitude value of the sensor signal dx is set to 0, the maximum 512 range is set in the positive direction, and the −512 range is set in the negative direction.

  Returning now to FIG. The set value of the amplifying unit 17 is m (m is a natural number satisfying 4 ≦ m ≦ 9), and the set value m (that is, the initial set value) of the amplifying unit 17 at the measurement start time of the measuring apparatus 102 is 4 And the gain GN is set to 16 (S307).

  Next, the set value m is set as the initial set value 4, and the amplitude of the sensor signal dx in a predetermined period (a period from 0 second to 4 seconds after the start of measurement) is measured (S308).

  In addition, as an amplitude threshold value serving as a reference for determining the degree of the ratio of the amplitude value of the sensor signal dx in the predetermined period to the allowable amplitude value, a first amplitude threshold value of 16, a second amplitude threshold value of 32, and a value of A third amplitude threshold value of 64, a fourth amplitude threshold value of 128, and a fifth amplitude threshold value of 256 are used.

  Here, when the amplitude value of the sensor signal dx in the predetermined period is x and the value of the amplitude threshold value is y, the amplification unit control unit 150 sets the amplitude threshold value corresponding to the minimum y satisfying x <y as the first threshold value. The first amplitude value to the fifth amplitude value are specified (S309).

(Case 1)
The amplification unit control unit 150 sets the setting value m of the amplification unit 17 to 9 when the specified amplitude threshold is the first amplitude threshold (value 16). When the set value m of the amplification unit 17 is 9, the gain GN of the amplification unit 17 is set to 512.

(Case 2)
The amplification unit control unit 150 sets the value of the setting value m of the amplification unit 17 to 8 when the specified amplitude threshold is the second amplitude threshold (value 32). When the set value m of the amplification unit 17 is 8, the gain GN of the amplification unit 17 is set to 256.

(Case 3)
The amplification unit control unit 150 sets the set value m of the amplification unit 17 to 7 when the specified amplitude threshold is the third amplitude threshold (value 64). When the set value m of the amplification unit 17 is 7, the gain GN of the amplification unit 17 is set to 128.

(Case 4)
The amplification unit control unit 150 sets the setting value m of the amplification unit 17 to 6 when the specified amplitude threshold is the fourth amplitude threshold (value 128). When the set value m of the amplifying unit 17 is 6, the gain GN of the amplifying unit 17 is set to 64.

(Case 5)
The amplification unit control unit 150 sets the set value m of the amplification unit 17 to 5 when the specified amplitude threshold is the fifth amplitude threshold (value 256). When the set value m of the amplifying unit 17 is 5, the gain GN of the amplifying unit 17 is set to 32.

(Case 6)
Case 6 is when the amplitude value of the sensor signal dx is larger than the fifth amplitude threshold value (value 256). In this case, according to FIG. 21B, gain adjustment (adjustment for reducing the gain GN) is performed in consideration of the number of shakes and the like.

  Thus, in the example of FIG. 21A, the amplification unit control unit 150 converts the sensor signal dx from the first amplitude threshold value to the first amplitude threshold value having each of the five amplitude threshold values (16, 32, 64, 128, 256). By comparing with (5 amplitude threshold), “the degree of the ratio of the amplitude value of the sensor signal dx to the predetermined allowable amplitude value” is determined.

  Here, the midpoint value of the allowable amplitude value of the sensor signal dx is set to 0, and the upper limit value is set to 512. In addition, when the amplitude value of the sensor signal dx in the predetermined period is x and the amplitude threshold value is y, the amplification unit controller 150 sets the amplitude threshold corresponding to the minimum y satisfying x <y as the first threshold value. The amplitude value is specified from the fifth amplitude value.

  Then, the amplification unit control unit 150 determines the value of the setting value m of the amplification unit 17 according to which of the specified amplitude threshold value is between the first amplitude threshold value and the fifth amplitude value. According to the example of FIG. 21A, the sensor signal dx is compared with a plurality of amplitude threshold values, and the set value m of the amplification unit 17 and the gain GN of the amplification unit 17 are calculated according to the comparison result. can do.

  In the example of FIG. 21B, a specific example in the case of reducing the gain GN is shown. In the example of FIG. 21B, the midpoint value of the allowable amplitude value of the sensor signal dx is set to 0, a maximum range of 512 is set in the positive direction, and a range of −512 is set in the negative direction. A case that does not fall within this range is called a shakeout. Here, the shake in the positive direction is a case where the amplitude value of the sensor signal dx exceeds the upper limit value (512) of the dynamic range, and the shake in the negative direction exceeds the lower limit value (−512) of the dynamic range. Is less than In the example of FIG. 21B, the set value m is not set to 0 in the first set value review process after the start of measurement.

  When it is determined as case 6 by the determination according to FIG. 21A, the amplification unit controller 150 executes the determination according to FIG. 21B and sets the set value m according to the conditions such as case 7 to case 11. Determine the value of.

(Case 7)
When the value obtained by adding the number of shakes in the positive direction and the number of shakes in the negative direction is 10 or more, the set value m is set to 1.

(Case 8)
The set value m is set to 3 when the number of shakes in the positive direction is 2 or more, or when the number of shakes in the negative direction is 2 or more. However, this is only an example and can be modified. For example, a difference may be provided in the adjusted sensitivity between the case where the swing is positive and the case where the swing is negative.

(Case 9)
The set value m is set to 3 when the number of shakes in the positive direction is 1 or more, or when the number of shakes in the negative direction is 1 or more.

(Case 10)
Although there is no shaking, if the peak value of the sensor signal dx is 388 or more of the dynamic range (−512 to 512), the set value m is set to 3.

(Case 11)
Although there is no shaking, the set value m is set to 4 if the peak value of the sensor signal dx is less than 388 in the dynamic range (−512 to 512).

  Each determination condition shown in FIG. 21B is an example, and only one of the determination conditions can be used, or a plurality of determination conditions can be used in any combination. is there.

  The gain value estimation process is thus completed.

  Then, as shown in the upper part of FIG. 22B, the waveform or the like of the AC component signal is displayed on the display unit 70 (S202). Although the display of S202 is not essential, since it is possible to notify the user that the signal can be appropriately acquired by the pulse wave sensor 11, it is possible to give a sense of security that there is no device defect or the like.

  Thereafter, a variable n representing the band hole position is initialized (S203). Here, n = 1. Here, the variable n represents the band hole position recognized by the pulse meter side, and guarantees that the actual holding state of the holding mechanism 300 is the holding state by the band hole position corresponding to n. It is not a thing. However, as will be described later, when the user follows the instruction on the instruction screen, the band hole position recognized by the system corresponds to (matches) the actual holding state.

  Next, as shown in the lower part of FIG. 22B, control is performed to display an instruction screen for instructing the user so that the band hole position recognized on the system side matches the actual holding state. At the same time, an input from the user is accepted (S204). In the example of FIG. 22 (B), the user tries to hold at the indicated band hole position, and if the band can be tightened, input OK, and it is too tight to tighten or is too loose to fix sufficiently. If it is not possible, etc., NG is input. However, the interaction with the user is not limited to this.

  The user's input to S204 is accepted, and it is determined whether or not OK has been input (S205). In the case of Yes in S205, it is considered that the attachment at the band hole position indicated on the instruction screen has been completed, and it is determined whether the conditions for the determination environment described in the gain value estimation process are satisfied (S206 to S206). S211). If it is satisfied, the processing based on the AC component signal and the processing based on the DC component signal are performed (S212, S213).

  In S212, processing for obtaining the amplitude value of the AC component signal is performed, and in S213, processing for obtaining the representative value (average value) of the DC component signal is performed. Since specific processing has been described above, detailed description thereof will be omitted.

  After the processing of S213, or when it is determined No in S205, n is incremented (S214), and it is determined whether the processing for all the band holes has been completed (S215). In the case of No in S215, since it is necessary to perform processing at the band hole position corresponding to n after the increment in S214, the process returns to S204, and the band hole position recognized on the system side and the actual holding Control is performed to display an instruction screen for instructing the user so that the states match, and at the same time, input from the user is accepted. The following processing is the same.

  In the case of Yes in S215, this means that the processing at all the band hole positions has been completed, and therefore, based on the amplitude value of the AC component signal calculated at each band hole position and the representative value of the DC component signal. Then, the proper pressing is determined (S216). Specifically, the processing shown in the flowchart of FIG.

  Then, the band hole position (holding state specifying information in a broad sense) corresponding to the appropriate pressing is stored, and a screen for notifying the user of the appropriate band hole position is displayed as shown in FIG. Control to be displayed on the unit 70 is performed (S217).

  As described above, when determining the appropriate pressure, the gain GN is set to an appropriate value according to the pulse intensity, and the signal is amplified, so that the determination of the appropriate pressure can be accurately performed in response to individual differences in the pulse intensity. The effect that it becomes possible to perform can be expected.

  In the above embodiment, as shown in FIG. 5, the pulse meter has a pulse wave detection unit 10 including a pulse wave sensor 11 that outputs a pulse wave sensor signal and an amplification unit 17 that amplifies the pulse wave sensor signal. The processing unit 100 that calculates pulsation information based on the signal from the pulse wave detection unit 10, the display unit 70 that displays the processing result in the processing unit 100, and the storage unit that stores the processing result in the processing unit 100 90 and a holding mechanism 300 (shown in FIG. 4A) for holding the pulse meter on the subject. Then, the processing unit 100 determines whether or not the pressure on the subject in the pulse wave detection unit 10 is an appropriate pressure. The storage unit 90 stores the holding state specifying information when it is determined that the pressure on the subject in the pulse wave detection unit 10 is an appropriate pressure. In addition, the processing unit 100 performs control to display the holding state specifying information on the display unit 70.

  Here, the holding state specifying information is information for specifying the holding state in the holding mechanism 300. For example, if the pulse meter is a device held by a band as shown in FIG. 4A, the holding state specifying information is information for specifying the state of the band. Specifically, when a band is fixed using a hole as shown in FIG. 7, information indicating what number band hole position is used to hold the pulse meter is the holding state specifying information. The band is not limited to those using holes, and a velcro type band with a scale or a ratchet type band may be used. The holding mechanism 300 is not limited to the band, and any mechanism can be used as long as the pulse meter can be fixed to the subject and the sensor information acquisition by the pulse wave sensor 11 is not hindered.

  As a result, it is possible to store and display the holding state specifying information corresponding to the appropriate pressure after determining the appropriate pressure with the pulse meter. Even if the proper pressure can be obtained in units of kPa, mmHg, or the like, it is not easy to determine what state the holding mechanism 300 should be in order to realize the proper pressure. In that regard, by associating the appropriate pressure with the holding state specifying information, the user does not need to be aware of the numerical value of the appropriate pressure, etc., and whether or not the proper pressure is achieved by an intuitive method such as band tightening. Can be recognized. For this reason, once the determination of proper pressing is performed, the state in which the proper pressing is applied can be easily reproduced even when the device is remounted, and the convenience of the user is expected to be improved. it can.

  In addition, the appropriate pressure is a pressure in a range larger than the pressure corresponding to the vein vanishing point (venous recovery point) and smaller than the pressure corresponding to the arterial vanishing point (arterial recovery point) as described above. That is, in the present embodiment described above, the pulse meter has a pulse wave sensor 11 that outputs a pulse wave sensor signal, and a pulse wave detector 10 that has an amplifier 17 that amplifies the pulse wave sensor signal, and the pulse wave detector 10. A processing unit 100 that calculates pulsation information based on a signal from the display unit, a display unit 70 that displays a processing result in the processing unit 100, a storage unit 90 that stores a processing result in the processing unit 100, and a pulsometer. The pulse wave detection unit 10 includes a holding mechanism 300 that holds the subject, and sets the gain GN of the pulse AC component signal to an appropriate value according to the pulse intensity when determining the appropriate pressure. Is included in a range where the pressure on the subject in the pulse wave detection unit 10 is larger than the pressure corresponding to the venous vanishing point (venous recovery point) and smaller than the pressure corresponding to the arterial vanishing point (arterial recovery point). Whether or not, the storage unit 90 Stores holding state specifying information for specifying the holding state of the holding mechanism 300 when it is determined that the pressure on the subject in the exit unit is included in the range, and the processing unit 100 displays the holding state specifying information on the display unit. You may perform control displayed on 70. FIG.

  Moreover, the process part 100 may determine whether a press is an appropriate press based on a pulse wave sensor signal.

  As a result, it is possible to perform appropriate pressure determination in consideration of individual differences. In the conventional method, processing based on physical information such as pressure values was performed, so individual differences were not taken into account, but by using a pulse wave sensor signal that is a vital sign with large individual differences, it is appropriate for each user. The pressure can be appropriately determined. In addition, it is possible to cope with fluctuations in the appropriate pressure based on changes in physical condition of the same user. It is possible to improve the accuracy of the obtained pulsation information by performing pulsation information calculation or the like in a state where the appropriate pressure determined by the method of the present embodiment is applied.

  Further, the processing unit 100 determines that the pressing is an appropriate pressing based on at least one of an AC component signal corresponding to the AC component of the pulse wave sensor signal and a DC component signal corresponding to the DC component of the pulse wave sensor signal. It may be determined whether or not.

  Here, the AC component signal corresponds to the high-frequency component and the DC component corresponds to the low-frequency component, but the reference frequency may be determined based on, for example, the pulsation frequency. Considering that the AC component signal is also used for calculation of pulsation information, it is required to include a component due to the heartbeat. Considering the biological characteristics of the subject, a typical lower limit value of the pulse rate can be determined to some extent. For example, there are not many cases where the pulse rate falls below 30 (times / minute). Therefore, since it is considered rare that a signal caused by a heartbeat is included in a frequency band equal to or lower than the frequency (0.5 Hz) corresponding to the pulse rate 30, a frequency higher than the frequency is set to a high frequency component and lower than that. The frequency may be a low frequency component.

  As a result, it is possible to perform appropriate pressure determination using at least one of the AC component signal and the DC component signal. The AC component signal is characterized by an amplitude value, and the DC component signal is characterized by an inflection point. Although it is possible to determine the appropriate pressure from either one, as shown in the flowchart of FIG. 12, it is possible to improve the determination accuracy by using both signals.

  Further, the processing unit 100 may determine whether or not the pressing is an appropriate pressing based on the change characteristic of the AC component signal when the pressing is changed. Specifically, it may be determined whether or not the pressing is an appropriate pressing based on the change characteristic of the amplitude of the AC component signal when the pressing is changed.

  Thereby, the determination based on the change characteristic of the AC component signal with respect to the pressing can be performed. The pulse wave sensor signal is a vital sign having a large individual difference, and the AC component signal corresponding to the AC component also has a large individual difference. Therefore, since there is an individual difference in the magnitude of the signal value at the time of proper pressing, it is difficult to determine whether or not the pressing is the proper pressing only from the signal value at a given pressing. On the other hand, if the change characteristic with respect to the pressure is used, an appropriate determination that is not influenced by the individual difference can be made. As shown in FIG. 8, since it is known that the AC component signal has a relatively large amplitude value at the appropriate press, the determination may be made based on the change characteristic of the amplitude value.

  Moreover, the process part 100 may determine whether a press is an appropriate press based on the change characteristic of a DC component signal at the time of changing a press. Specifically, the inflection point of the DC component signal is detected based on the change characteristic of the DC component signal when the pressure is changed, and whether or not the pressure is an appropriate pressure based on the detected inflection point. May be determined.

  Thereby, the determination based on the change characteristic of the DC component signal with respect to the pressing can be performed. The DC component signal represents the volume of blood flow, and in the pressurization (decompression) process, an inflection point appears at the venous vanishing point (venous recovery point) and the arterial vanishing point (arterial recovery point). Appropriate pressure determination can be performed, and when the appropriate pressure is obtained as a range, the upper limit value and the lower limit value can be accurately determined.

  Further, the processing unit 100 may perform control to display an instruction screen for instructing setting of an environment for determination as to whether or not the pressing is an appropriate pressing on the display unit 70.

  Here, the determination environment is, for example, an environment that satisfies the condition that the body movement is stable, the posture is not abnormal, and a certain time has passed since the holding state in the holding mechanism 300 is determined. It is. It should be noted that conditions other than the above may be added to the judgment environment, and some or all of the above conditions (when other conditions are added) may be excluded, and the contents can be variously set. It is.

  Thereby, it is possible to issue an instruction for setting the environment for determination. Unlike the conventional method using a pressure value or the like, in this embodiment, since the determination is performed based on a pulse wave sensor signal that is a vital sign, the signal value also fluctuates due to factors other than a change in pressure. Since it is difficult to identify and isolate the fluctuation factor only from the signal value of the pulse wave sensor signal, it is necessary to suppress the fluctuation of the signal value due to a factor other than pressing as much as possible. In this case, an environment satisfying such a condition is used as a determination environment, and an instruction is given to the user so as to satisfy the determination environment, thereby making it possible to accurately determine the appropriate pressure.

  Further, the processing unit 100 may perform control to display a screen for instructing stabilization of body movement of the subject on the display unit 70 as an instruction screen.

  Thereby, it becomes possible to instruct the stabilization of body movement. When the body motion is large, a component (body motion noise) due to the body motion is mixed in the pulse wave sensor signal, and the body motion noise is also added to the AC component signal and the DC component signal obtained therefrom. End up. Therefore, in order to suppress the influence of body motion noise and perform accurate proper pressure determination, it is desirable to stabilize body motion. Since the body movement is performed by the user and it is difficult for the pulse meter to physically suppress the user's body movement, it is a realistic and effective technique to give an instruction in an easy-to-understand manner for the user.

  In addition, the processing unit 100 may perform control to display on the display unit 70 a screen for instructing the subject to take a given determination posture as an instruction screen.

  Here, the determination posture refers to a posture defined based on the relative positional relationship between the heart of the subject and the pulse wave detection unit 10. When the relative positional relationship (specifically, the height) between the subject's heart and the pulse wave detector 10 varies, the hydraulic head pressure varies. For example, when the arm is raised, the blood flow rate is reduced due to a change in the hydrocephalic pressure, compared to a state where the arm is lowered. In other words, the determination posture here is a posture that is set in order to prevent the blood flow from fluctuating due to the hydraulic head pressure (independent of the pressure change).

  Thereby, since it can suppress that an abnormal posture is taken at the time of appropriate press determination, it becomes possible to suppress the precision fall of the appropriate press determination resulting from water head pressure. The determination posture is preferably a posture in which the user can see the display unit 70 naturally (for example, a posture when viewing the dial part of a wristwatch) in the present embodiment on the assumption that the display unit 70 interacts. However, the present invention is not limited to this. A method of displaying instructions to the user on the display unit 70 as well as stabilization of body movement is considered to be easy to understand and effective.

  Further, the processing unit 100 may perform control to display a screen for instructing the subject to wait for a given time on the display unit 70 as an instruction screen.

  Thereby, it is possible to accurately determine the appropriate pressure by allowing the user to wait for a certain period of time. This is because when a manual band adjustment is actually performed, a certain amount of work time is required, and as shown in FIGS. 9A and 11, a certain time (about 10 seconds) is required until the signal value itself is stabilized. ).

  In addition, the processing unit 100 determines whether or not the condition for the determination environment displayed on the instruction screen is satisfied, and when it is determined that the condition is satisfied, whether or not the pressing is an appropriate pressing. A determination may be made. Specifically, based on the body motion detection signal from the body motion sensor or the time measurement information from the time measurement unit, it is determined whether or not the conditions for the determination environment displayed on the instruction screen are satisfied.

  Thereby, when the conditions for the environment for determination are satisfy | filled, it becomes possible to perform appropriate press determination. By displaying the instruction screen on the display unit 70, it is possible to send an instruction for realizing the determination environment to the user, but it is not guaranteed whether the user actually follows the instruction. Therefore, it is possible to improve the determination accuracy by determining whether the condition is satisfied on the system side and performing processing when the condition is satisfied. For stabilization of body motion and elimination of abnormal posture, a body motion sensor such as the acceleration sensor 21 may be used as shown in FIGS. 15A, 17A, and 17B. Further, regarding the passage of time, time measurement information from the time measurement unit 140 realized by a timer or the like may be used.

  Moreover, the process part 100 may have holding | maintenance state specific information acquisition mode and the pulsation information calculation mode which calculates pulsation information as a processing mode. When the appropriate pressing determination mode is set, the holding state specifying information is acquired based on the determination result as to whether or not the pressing is an appropriate pressing, and the acquired holding state specifying information is stored in the storage unit 90. Then, when the pulsation information calculation mode is set after acquiring the holding state specifying information, the holding state specifying information stored in the storage unit 90 is read, and the read holding state specifying information is displayed on the display unit 70. You may go.

  Accordingly, in the holding state specifying information acquisition mode, the holding state specifying information can be displayed on the display unit 70 in the pulsation information calculation mode after performing the appropriate pressure determination and acquiring the holding state specifying information. When calculating beat information, it is possible to easily realize a holding state suitable for the calculation. Even if the proper pressing is determined and the holding state specifying information at that time is obtained, it is not effective if the result cannot be used for calculation of pulsation information which is the main processing of the pulsometer. Therefore, taking into consideration that the acquisition of the holding state specifying information and the calculation of the pulsation information are not continuous, the acquired holding state specifying information needs to be temporarily stored in the storage unit 90, and the pulsation information calculation is performed. When entering the mode, it is necessary to present the holding state specifying information in an easy-to-understand manner to the user.

  Moreover, the holding mechanism 300 may take the first to Nth (N is an integer of 2 or more) states in which the pressure on the subject in the pulse wave detection unit 10 is different as the holding state. And the process part 100 respond | corresponds to at least 1 state among 1st-Nth states based on the determination result whether the press in each state of a 1st-Nth state is an appropriate press. Information to be acquired is acquired as holding state specifying information.

  As a result, in the holding mechanism 300 (for example, a band having a hole) that can take a plurality of discrete holding states, the above-described processing is performed, and at least one of the plurality of holding states is obtained as the holding state specifying information as a result. It is possible to acquire two states (for example, the state of holding at the position of the band hole).

  Further, after determining whether or not the pressing in the i-th state (i is an integer satisfying 1 ≦ i ≦ N) is an appropriate pressing, the processing unit 100 changes the holding state in the holding mechanism 300 to the i-th state. Control may be performed to display on the display unit 70 an instruction screen for instructing to change to a jth state (j is an integer satisfying 1 ≦ j ≦ N, j ≠ i) in which the pressure is smaller than that in the state.

  As a result, it is possible to make an appropriate pressure determination in the decompression process. Examples are shown in FIGS. 23A to 23C. As shown in FIG. 23C, here, pressurization is performed in the first half and decompression is performed in the second half. It should be noted that a very large pressure appears when the band hole position is changed, and a large signal value also appears in the corresponding AC component signal, but this is excluded in the proper pressure determination as shown in FIG. It is what is done.

  As shown in FIG. 23B, since the AC component signal has a large amplitude before and after the band hole position 7 in both the pressurizing process and the depressurizing process, it is possible to determine appropriate pressing. However, since the pressure reduction process has a larger amplitude value, the determination is considered easier.

  On the other hand, as shown in FIG. 23A, the inflection point of the DC component signal is clear in the depressurization process, but unclear in the pressurization process. Considering even a small fluctuation of the signal value, it is possible to detect the inflection point of the DC component signal in the pressurization process, but the determination in the decompression process is easier as in the case of the AC component signal.

  From the above, it is possible to perform the determination with higher accuracy than in the case of using the pressurization process by performing the appropriate pressure determination in the decompression process.

  Further, the present embodiment described above determines the pulse wave detection unit 10 having the pulse wave sensor 11 and whether or not the pressure on the subject in the pulse wave detection unit 10 is an appropriate pressure, and the pulse wave detection unit 10 A pulse meter including a processing unit 100 that calculates pulsation information of a subject based on a signal, a display unit 70 that displays a processing result in the processing unit 100, and a storage unit 90 that stores a processing result in the processing unit 100. Applicable to. Then, the processing unit 100 performs control to display on the display unit 70 an instruction screen for instructing setting of an environment for determination as to whether or not the pressing is an appropriate pressing.

  Accordingly, even when the pressing is changed by a method other than holding by the holding mechanism 300, the pressing determination can be performed in an appropriate situation by displaying the determination environment instruction screen. Regardless of the method of pressing change, it is not preferable that the signal value used for proper pressing determination fluctuates due to factors other than the pressing change. The advantage of displaying an instruction screen for instructing setting on the display unit 70 is great.

  In addition, the processing unit 100 determines whether or not the conditions for the determination environment displayed on the instruction screen are satisfied, and based on the signal from the pulse wave detection unit 10 when it is determined that the conditions are satisfied. It may be determined whether or not the pressing is an appropriate pressing.

  As a result, it is possible to perform appropriate pressure determination based on a signal (a pulse wave sensor signal in a narrow sense, and at least one of an AC component signal and a DC component signal in a narrow sense) when the conditions for the determination environment are satisfied. Become. The advantages of determining whether or not the conditions for the determination environment are satisfied on the system side and using the signal from the pulse wave detection unit 10 for the appropriate pressure determination are as described above.

  Moreover, the pulse meter of this embodiment may implement | achieve part or most of the process with a program. In this case, the pulse meter according to the present embodiment is realized by a processor such as a CPU executing a program. Specifically, a program stored in the information storage medium is read, and a processor such as a CPU executes the read program. Here, the information storage medium (computer-readable medium) stores programs, data, and the like, and functions as an optical disk (DVD, CD, etc.), HDD (hard disk drive), or memory (card type). It can be realized by memory, ROM, etc. A processor such as a CPU performs various processes according to the present embodiment based on a program (data) stored in the information storage medium. That is, in the information storage medium, a program for causing a computer (an apparatus including an operation unit, a processing unit, a storage unit, and an output unit) to function as each unit of the present embodiment (a program for causing the computer to execute processing of each unit) Is memorized.

  Although the present embodiment has been described in detail as described above, it will be easily understood by those skilled in the art that many modifications can be made without departing from the novel matters and effects of the present invention. Accordingly, all such modifications are intended to be included in the scope of the present invention. For example, a term described with a different term having a broader meaning or the same meaning at least once in the specification or the drawings can be replaced with the different term in any part of the specification or the drawings. The configuration and operation of the pulse meter are not limited to those described in the present embodiment, and various modifications can be made.

  DESCRIPTION OF SYMBOLS 10 Pulse wave detection part, 11 Pulse wave sensor, 15 Filter processing part, 16 A / D conversion part, 17 Amplification part, 20 Body motion detection part, 21 Acceleration sensor, 22 Pressure sensor, 26 A / D conversion part, 70 Display Unit, 80 external I / F unit, 90 storage unit, 100 processing unit, 110 signal processing unit, 111 pulse wave signal processing unit, 113 body motion signal processing unit, 115 body motion noise reduction unit, 119 proper pressure determination unit, 120 Beat information calculation unit, 130 display control unit, 140 time measurement unit, 150 amplification unit control unit, 300 holding mechanism, 302 guide, 400 base unit.

Claims (20)

A pulse wave detection unit having a pulse wave sensor that outputs a pulse wave sensor signal and an amplification unit that amplifies the pulse wave sensor signal;
A processor that calculates pulsation information based on a signal from the pulse wave detector;
A display unit for displaying a processing result in the processing unit;
A storage unit for storing a processing result in the processing unit;
A holding mechanism for holding a pulse meter on the subject;
Including
The pulse wave detector
When determining the appropriate pressure, the gain of the AC component signal of the pulse is set to an appropriate value according to the pulse intensity,
The processor is
It is determined whether or not the pressure on the subject in the pulse wave detection unit is an appropriate pressure,
The storage unit
Storing holding state specifying information for specifying the holding state of the holding mechanism when it is determined that the pressure on the subject in the pulse wave detection unit is the appropriate pressure;
The processor is
The pulsometer, wherein the holding state specifying information is displayed on the display unit. In claim 1,
The processor is
It is determined whether the said press is the said appropriate press based on the said pulse wave sensor signal, The pulse meter characterized by the above-mentioned. In claim 2,
The processor is
Whether or not the pressing is the appropriate pressing based on at least one of an AC component signal corresponding to the AC component of the pulse wave sensor signal and a DC component signal corresponding to the DC component of the pulse wave sensor signal A pulse meter, characterized by determining. In claim 3,
The processor is
A pulse meter that determines whether or not the pressing is the proper pressing based on a change characteristic of the AC component signal when the pressing is changed. In claim 4,
The processor is
A pulse meter that determines whether or not the pressure is the appropriate pressure based on a change characteristic of the amplitude of the AC component signal when the pressure is changed. In claim 3,
The processor is
A pulse meter that determines whether or not the pressure is the appropriate pressure based on a change characteristic of the DC component signal when the pressure is changed. In claim 6,
The processor is
An inflection point of the DC component signal is detected based on a change characteristic of the DC component signal when the pressing is changed, and whether the pressing is the proper pressing based on the detected inflection point. A pulse meter characterized by determining whether or not. In any one of Claims 1 thru | or 7,
The processor is
A pulsometer characterized by performing control to display on the display unit an instruction screen for instructing setting of an environment for determination as to whether or not the pressing is the appropriate pressing. In claim 8,
The processor is
A pulsometer, wherein a screen for instructing stabilization of body movement of the subject is displayed on the display unit as the instruction screen. In claim 8 or 9,
The processor is
A pulsometer, characterized in that control is performed to display on the display unit a screen for instructing the subject to take a given determination posture as the instruction screen. In any one of Claims 8 thru | or 10.
The processor is
A pulsometer characterized by performing control to display a screen for instructing the subject to wait for a given time on the display unit as the instruction screen. In any of claims 9 to 11,
The processor is
It is determined whether or not the conditions for the determination environment displayed on the instruction screen are satisfied. When it is determined that the conditions are satisfied, it is determined whether or not the pressure is the appropriate pressure. A pulse meter characterized by what to do. In claim 12,
The processor is
Based on at least one of the body motion detection signal from the body motion sensor and the time measurement information from the time measurement unit, it is determined whether or not the condition of the determination environment displayed on the instruction screen is satisfied. When the condition is determined to be satisfied, it is determined whether or not the pressure is the appropriate pressure. In any one of Claims 1 thru | or 13.
The processor is
As a processing mode, it has a holding state specifying information acquisition mode and a pulsation information calculation mode for calculating the pulsation information,
When the appropriate pressing determination mode is set, the holding state specifying information is acquired based on a determination result of whether or not the pressing is the appropriate pressing, and the acquired holding state specifying information is stored in the storage unit. Remember
When the pulsation information calculation mode is set after acquisition of the holding state specifying information, the holding state specifying information stored in the storage unit is read and the read holding state specifying information is displayed on the display unit. A pulse meter characterized by performing control. In any one of Claims 1 thru | or 14.
The holding mechanism is
As the holding state, take the first to Nth (N is an integer of 2 or more) different states of the pressure on the subject in the pulse wave detection unit,
The processor is
Information corresponding to at least one of the first to Nth states is based on the determination result of whether or not the pressing in each of the first to Nth states is the appropriate pressure. A pulse meter obtained as the holding state specifying information. In claim 15,
The processor is
After determining whether or not the pressing in the i-th state (i is an integer satisfying 1 ≦ i ≦ N) is the appropriate pressing, the holding state in the holding mechanism is changed from the i-th state. And a control for displaying on the display unit an instruction screen for instructing to change to a j-th state where the pressure is small (j is an integer satisfying 1 ≦ j ≦ N and j ≠ i). . A pulse wave detector having a pulse wave sensor;
A processing unit that determines whether or not the pressure on the subject in the pulse wave detection unit is an appropriate pressure, and calculates pulsation information of the subject based on a signal from the pulse wave detection unit;
A display unit for displaying a processing result in the processing unit;
A storage unit for storing a processing result in the processing unit;
Including
The processor is
A pulsometer characterized by performing control to display on the display unit an instruction screen for instructing setting of an environment for determination as to whether or not the pressing is the appropriate pressing. In claim 17,
The processor is
It is determined whether or not the condition for the determination environment displayed on the instruction screen is satisfied, and the pressing is performed based on the signal from the pulse wave detection unit when it is determined that the condition is satisfied It is determined whether or not the pressure is appropriate. A pulse wave detection unit having a pulse wave sensor that outputs a pulse wave sensor signal and an amplification unit that amplifies the pulse wave sensor signal;
A processor that calculates pulsation information based on a signal from the pulse wave detector;
A display unit for displaying a processing result in the processing unit;
As a storage unit for storing the processing result in the processing unit,
Make the computer work,
The processor is
It is determined whether or not the pressure on the subject in the pulse wave detection unit is an appropriate pressure,
The storage unit
Storing holding state specifying information for specifying a holding state of a holding mechanism that holds a pulse meter on the subject when it is determined that the pressure on the subject in the pulse wave detection unit is the appropriate pressure; ,
The processor is
A program for performing control to display the holding state specifying information on the display unit. A pulse wave detection unit having a pulse wave sensor and an amplification unit for amplifying the pulse wave sensor signal;
A processing unit that determines whether or not the pressure on the subject in the pulse wave detection unit is an appropriate pressure, and calculates pulsation information of the subject based on a signal from the pulse wave detection unit;
A display unit for displaying a processing result in the processing unit;
As a storage unit for storing the processing result in the processing unit,
Make the computer work,
The processor is
The program which performs control which displays the instruction | indication screen which performs the setting instruction | indication of the environment for determination whether the said press is the said appropriate press on the said display part.

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