JP5742520B2 - Biological information processing apparatus and biological information processing method - Google Patents

Description

  The present invention relates to a biological information processing apparatus and a biological information processing method.

  2. Description of the Related Art Conventionally, as a biological information processing apparatus used for exercise management and health management of a subject, a pulsometer that is attached to a part of the subject's body and measures the subject's pulse rate is known. The pulse meter detects a change in blood flow of the subject wearing the device, calculates the pulse rate of the subject, and calculates the calculated pulse rate (hereinafter referred to as “calculated pulse rate”) as a measurement result. This is to notify the subject. As a pulsometer, one using light, one using ultrasonic waves, one using electrocardiogram, and the like are known.

  Whether or not the pulse rate can be calculated correctly depends largely on the accuracy with which changes in the blood flow of the subject are detected. However, the accuracy of detecting a change in blood flow may be reduced due to an influence of disturbance such as a change in outside air temperature, a physical effect such as a position of the pulse meter and a shift in the position of attachment. In view of this, a method has been devised in which an allowable range of variation for the calculated pulse rate is set to determine the suitability of the calculated pulse rate (for example, Patent Document 1 and Patent Document 2).

JP-A-9-113309 JP-A-9-154825

  However, as in the techniques of Patent Document 1 and Patent Document 2, in the method using the allowable fluctuation range, it is required to set an appropriate fluctuation allowable range each time the pulse rate calculation timing arrives. . In particular, when the subject's exercise status (exercise start, exercise stop, etc.) changes, the subject's pulse rate changes abruptly, making it difficult to follow the fluctuation tolerance range with the time change of the pulse rate. A nasty scene could have occurred.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to propose a new method for determining the suitability of the calculated pulse rate.

  A first mode for solving the above problems is a pulse rate calculation unit that calculates a pulse rate of a subject, a given reference pulse rate, and a calculated pulse rate calculated by the pulse rate calculation unit. A divergence degree determination unit that determines the divergence degree, a reliability determination unit that determines reliability of the calculation result of the pulse rate calculation unit, and the suitability of the calculated pulse rate based on the divergence degree and the reliability A biometric information processing apparatus including a fitness determination unit.

  Further, as another form, calculating the pulse rate of the subject, determining the degree of divergence between the given reference pulse rate and the calculated pulse rate, and calculating the pulse rate A biological information processing method including determining reliability and determining appropriateness of the calculated pulse rate based on the degree of deviation and the reliability may be configured.

  According to the first aspect, the divergence degree between the given reference pulse rate and the calculated pulse rate calculated by the pulse rate calculation unit is determined by the divergence degree determination unit. Further, the reliability of the calculation result of the pulse rate calculation unit is determined by the reliability determination unit. The suitability determination unit determines whether the calculated pulse rate is appropriate based on the degree of deviation and the reliability.

  The degree of divergence is a measure of how far the reference pulse rate is from the calculated pulse rate. Usually, a situation in which the subject's pulse rate changes rapidly in a short time is rare. Therefore, the accuracy of the calculated pulse rate can be determined to some extent from the degree of divergence between the given reference pulse rate and the calculated pulse rate. In addition, by determining whether the calculated pulse rate is appropriate using the reliability of the calculation result of the pulse rate calculating unit, it is possible to reliably determine whether the calculated pulse rate is appropriate. The reference pulse rate may be a value serving as a reference for the pulse rate. For example, the latest calculated pulse rate determined to be appropriate by the suitability determination can be set.

  Further, as a second mode, in the biological information processing apparatus according to the first mode, the suitability determination unit has a predetermined reliability determined so that the smaller the divergence degree, the easier the determination of the calculated pulse rate is. A biological information processing apparatus having a reliability condition determination unit that determines whether or not a sex condition is satisfied, and determining whether the calculated pulse rate is appropriate based on a determination result of the reliability condition determination unit Also good.

  According to the second embodiment, the reliability condition determination unit determines whether or not a predetermined reliability condition is satisfied. The reliability condition is determined so that the smaller the degree of divergence between the reference pulse rate and the calculated pulse rate, the easier it is to determine that the calculated pulse rate is appropriate. Therefore, it is possible to determine whether the calculated pulse rate is appropriate according to the reliability condition optimized in accordance with the degree of deviation between the reference pulse rate and the calculated pulse rate.

  Further, as a third mode, in the biological information processing apparatus according to the second mode, the suitability determination unit, when the divergence degree satisfies a predetermined high divergence condition, continues the positive determination by the reliability condition determination unit. A biological information processing apparatus that determines the suitability of the calculated pulse rate based on the number of times may be configured.

  The greater the degree of deviation between the reference pulse rate and the calculated pulse rate, the higher the possibility that the calculated pulse rate is incorrect. Therefore, according to the third aspect, when the divergence degree satisfies a predetermined high divergence condition, the suitability of the calculated pulse rate is determined based on the number of consecutive positive determinations by the reliability condition determination unit. If an affirmative determination is made continuously, the calculated pulse rate is likely to be a reliable value. That is, the suitability of the calculated pulse rate can be determined from the number of consecutive positive determinations.

  Further, as a fourth mode, in the biological information processing apparatus according to the second mode, the body motion detection unit for detecting the body motion of the subject and the subject using the detection result of the body motion detection unit A body motion frequency determining unit that determines the frequency of periodic body motion, and the suitability determining unit is such that the frequency of the periodic body motion and the frequency of the calculated pulse rate are not approximated. A frequency condition determination unit that determines whether or not a predetermined frequency condition is satisfied, and when the degree of divergence satisfies a predetermined high divergence condition, the determination result of the frequency condition determination unit and the approximate condition determination unit The biological information processing apparatus may be configured to determine the suitability of the calculated pulse rate using the determination result.

  According to the fourth embodiment, the frequency of the periodic body motion of the subject is determined using the detection result of the body motion detection unit. Periodic body movement means body movement caused by a periodic movement such as a subject's arm swing. It is determined whether or not a predetermined frequency condition indicating that the frequency of the periodic body motion and the frequency of the calculated pulse rate are not approximated is satisfied. With this frequency condition, it is possible to determine the possibility of capturing periodic body movement as a pulse rate. As described above, the greater the degree of deviation between the reference pulse rate and the calculated pulse rate, the higher the possibility that the calculated pulse rate is incorrect. Therefore, when the divergence degree satisfies a predetermined high divergence condition, the accuracy of the determination of the appropriateness of the calculated pulse rate is determined by performing the appropriateness determination using the determination result of the reliability condition determination unit and the determination result of the frequency condition determination unit. Can be further increased.

  Further, as a fifth aspect, in the biological information processing apparatus according to the fourth aspect, the suitability determination unit is such that the determination result of the reliability condition determination unit is affirmative and the determination result of the frequency condition determination unit May be configured as a biological information processing apparatus that determines whether the calculated pulse rate is appropriate based on the number of consecutive positive determinations by the reliability condition determination unit.

  According to the fifth embodiment, when the determination result of the reliability condition determination unit is an affirmative determination and the determination result of the frequency condition determination unit is a negative determination, the affirmative determination by the reliability condition determination unit is continued. The suitability of the calculated pulse rate is determined based on the number of times. Even if the reliability of the calculation result is high, if the frequency of the periodic body motion is close to the frequency of the calculated pulse rate, the calculation result is likely to be an incorrect result. Therefore, in this case, the suitability of the calculated pulse rate is determined based on the number of consecutive positive determinations by the reliability condition determination unit.

  Further, as a sixth aspect, in the biological information processing apparatus according to the second aspect, a body motion detection unit that detects the body motion of the subject, and the subject using a detection result of the body motion detection unit A body motion state determination unit that determines a body motion state of the body, wherein the suitability determination unit determines whether or not the body motion state and the calculated pulse rate satisfy a predetermined matching condition And determining the suitability of the calculated pulse rate using the determination result of the reliability condition determination unit and the determination result of the matching condition determination unit when the divergence degree satisfies a predetermined high divergence condition The biological information processing apparatus may be configured.

  According to the sixth embodiment, the body motion state of the subject is determined using the detection result of the body motion detector. The body movement state is a movement state of the subject's body, and includes, for example, a state of calm and exercise. It is determined whether or not the physical movement state and the calculated pulse rate satisfy a predetermined matching condition. For example, if the calculated pulse rate is higher than expected even though the physical motion state is calm, the physical motion state and the calculated pulse rate are not consistent (inconsistent) ) Even when the physical motion state is an exercise state, it can be said that the physical motion state and the calculated pulse rate do not match even when the calculated pulse rate is lower than expected. As described above, the greater the degree of deviation between the reference pulse rate and the calculated pulse rate, the higher the possibility that the calculated pulse rate is incorrect. Therefore, when the degree of divergence satisfies a predetermined high divergence condition, the accuracy of determining the suitability of the calculated pulse rate is further increased by using the determination result of the reliability condition determination unit and the determination result of the matching condition determination unit. Can do.

  Further, as a seventh aspect, in the biological information processing apparatus according to the sixth aspect, the suitability determination unit has a positive determination result of the reliability condition determination unit and a determination result of the matching condition determination unit May be configured as a biological information processing apparatus that determines whether the calculated pulse rate is appropriate based on the number of consecutive positive determinations by the reliability condition determination unit.

  According to the seventh aspect, when the determination result of the reliability condition determination unit is an affirmative determination and the determination result of the matching condition determination unit is a negative determination, the positive determination by the reliability condition determination unit is continued. The suitability of the calculated pulse rate is determined based on the number of times. Even if the reliability of the calculation result is high, if the physical motion state and the calculated pulse rate are not consistent, the calculation result is likely to be an incorrect result. Therefore, in this case, the suitability of the calculated pulse rate is determined based on the number of consecutive positive determinations by the reliability condition determination unit.

The front view of a pulse meter. (A) Rear view of pulse meter. (B) The use state figure of a pulse meter. Explanatory drawing of operation | movement of a pulse wave sensor. Explanatory drawing of the setting method of a pulse range. The table block diagram of a condition definition table. The table block diagram of the table for suitability determination. The block diagram which shows the function structure of a pulse meter. The flowchart which shows the flow of a pulse rate measurement process. The table block diagram of the 2nd determination table.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. This embodiment is an embodiment in which the biological information processing apparatus of the present invention is applied to a wristwatch-type pulse meter. Needless to say, embodiments to which the present invention is applicable are not limited to the embodiments described below.

1. External Configuration FIG. 1 is a front view of a pulse meter 1 in the present embodiment. The pulsometer 1 includes a wristband 2, and the case 3, the time, the operating state of the pulsometer 1, and various biological information (pulse rate, exercise intensity, calorie consumption, etc.) are displayed by letters, numbers, icons, etc. A liquid crystal display 4 for this purpose is arranged.

  An operation button 5 for operating the pulsometer 1 is disposed on the peripheral portion (side surface) of the case 3. The pulse meter 1 operates using, for example, a built-in secondary battery as a power source. A charging terminal 6 for charging the built-in secondary battery is disposed on the side surface of the case 3 so as to be connected to an external charger.

  FIG. 2A is a rear view of the pulse meter 1 and shows an external view when the pulse meter 1 is viewed from the rear surface of the case 3. Moreover, FIG. 2 (B) is a use state diagram of the pulsometer 1 and shows a side view of the pulsometer 1 in a state of being worn on the wrist WR of the subject.

  A pulse wave sensor 10 that detects a pulse wave of the subject and outputs a pulse wave signal is disposed on the back surface of the case 3. The pulse wave sensor 10 detects a pulse wave at the wrist WR of the subject in contact with the back surface of the case 3. In the present embodiment, the pulse wave sensor 10 is a photoelectric pulse wave sensor and includes a mechanism for optically detecting the pulse wave.

  FIG. 3 is an enlarged view when the internal structure of the pulse wave sensor 10 is viewed from the side surface of the case 3. The pulse wave sensor 10 is installed in a hemispherical storage space having a circular bottom surface formed on the back side of the case 3. A light source 12 such as an LED (Light Emitting Diode) and a light receiving element 13 such as a phototransistor are built in the storage space. The inner surface of the hemisphere is a reflecting surface 11 that is a mirror surface, and the light receiving element 13 and the light source 12 are mounted on the upper surface and the lower surface of the substrate 14, respectively, when the bottom surface side of the hemisphere is downward.

  When the light Le is irradiated by the light source 12 toward the skin SK of the user's wrist WR, the irradiated light Le is reflected by the subcutaneous blood vessel BV and returns to the hemisphere as reflected light Lr. The reflected light Lr is further reflected by the hemispherical reflecting surface 11 and enters the light receiving element 13 from above.

  The intensity of the reflected light Lr from the blood vessel BV changes due to the absorption action of hemoglobin in the blood, reflecting the change in blood flow. The pulse wave sensor 10 blinks the light source 12 at a predetermined cycle at a cycle earlier than the pulsation. The light receiving element 13 outputs a pulse wave signal corresponding to the received light intensity by photoelectric conversion for each lighting opportunity of the light source 12. The pulse wave sensor 10 blinks the light source 12 at a frequency of, for example, 128 Hz.

  As shown in FIG. 2A, the pulsometer 1 includes a body motion sensor 20 for detecting the body motion of the subject. In the present embodiment, the body motion sensor 20 includes an acceleration sensor. As shown in FIG. 1, the acceleration sensor has, for example, the normal direction of the cover glass surface of the case 3 and the Z axis with the display surface side positive, and the vertical direction with the 12 o'clock direction of the watch as positive is the Y axis. This is a triaxial acceleration sensor having the X axis as the left-right direction with the 3 o'clock direction of the watch as positive.

  In a state where the pulsometer 1 is worn, the X axis coincides with the direction from the subject's elbow to the wrist. The body motion sensor 20 detects acceleration in three axes of the X axis, the Y axis, and the Z axis, and outputs the result as a body motion signal. The pulsometer 1 detects a periodic body movement (for example, an arm movement or a vertical movement of the body) of the subject accompanying walking or jogging based on the body movement signal detected by the body movement sensor 20. .

2. Principle The pulsometer 1 calculates the pulse rate of the subject using the pulse wave signal detected by the pulse wave sensor 10. Specifically, a predetermined frequency decomposition process is performed on the pulse wave signal, and a signal intensity value (spectrum value) for each frequency band is extracted. The frequency decomposition process can be a process to which, for example, a fast Fourier transform (FFT) is applied. Then, a frequency spectrum corresponding to the pulse wave of the subject is specified from the extracted signal intensity value, and the pulse rate is calculated based on the frequency (or period). The pulsometer 1 calculates the pulse rate at a predetermined time interval (for example, every 1 to 5 seconds). In the present embodiment, the pulse rate of the subject calculated as described above is referred to as “calculated pulse rate”.

  The pulse meter 1 notifies the subject by displaying the calculated pulse rate on the liquid crystal display 4 as the pulse rate of the measurement result (measured pulse rate). However, for example, a calculation greatly deviating from the actual pulse rate of the subject due to the influence of disturbance such as a change in the outside air temperature or the physical influence such as the wearing position of the pulse meter 1 and the deviation of the wearing position. The pulse rate may be obtained as a measurement result. The calculated pulse rate obtained in this case is an abnormal value, and it is not appropriate to notify the subject of the value. Therefore, in this embodiment, the suitability of the calculated pulse rate is determined according to the procedure described below.

  First, the degree of divergence between a given reference pulse rate and the calculated pulse rate is determined. The reference pulse rate is a reference value of the pulse rate at the calculation time (calculation timing) of the pulse rate. Although the reference pulse rate can be set as appropriate, in the present embodiment, the latest calculated pulse rate among the calculated pulse rates determined to be appropriate by the suitability determination is set as the reference pulse rate. Specifically, when it is determined that the calculated pulse rate is appropriate, the process of updating the reference pulse rate with the calculated pulse rate is repeated at each calculation time.

  The degree of divergence is a measure of how far the reference pulse rate is from the calculated pulse rate. It can be said that determining the degree of deviation between the reference pulse rate and the calculated pulse rate is determining the relative relationship between the reference pulse rate and the calculated pulse rate.

  FIG. 4 is an explanatory diagram of the degree of divergence between the reference pulse rate and the calculated pulse rate. FIG. 4 illustrates a pulse range that can be taken by the calculated pulse rate around the reference pulse rate at one calculation time. The horizontal axis is the pulse rate, and the center corresponds to the reference pulse rate.

  As shown in FIG. 4, a pulse range centered on the reference pulse rate and having a width “ΔH1” in each of the height directions is set as a “first pulse range”. A range that is an outer range based on the boundary of the first pulse range and is divided by the width “ΔH2” is set as a “second pulse range”. A range that is an outer range based on the boundary of the second pulse range and is divided by the width “ΔH3” is set as a “third pulse range”. Further, a range other than the above is set as the “fourth pulse range”. The values of “ΔH1 to ΔH3” that define the pulse range can be set as appropriate. For example, “ΔH1 = 10 beats, ΔH2 = 10 beats, ΔH3 = 20 beats” are set.

  When a short time interval is assumed, it is rare that the subject's pulse rate changes rapidly at the time interval. Therefore, the smaller the degree of deviation between the reference pulse rate and the calculated pulse rate, the higher the possibility that the calculated pulse rate is correct. However, a situation in which the pulse rate changes rapidly, such as when the subject starts exercising or stops exercising, is also assumed.

  Therefore, in the present embodiment, the difference between the reference pulse rate and the calculated pulse rate (hereinafter referred to as “pulse rate difference”) is calculated, and the difference between the reference pulse rate and the calculated pulse rate based on the pulse rate difference. Determine the degree. On the other hand, the reliability of the calculation result by pulse rate calculation is determined. Then, the suitability of the calculated pulse rate is determined based on the determined divergence degree and reliability.

  FIG. 5 is an explanatory diagram for determining whether or not the calculated pulse rate is appropriate, and illustrates a condition definition table that defines conditions used for determining appropriateness. In the condition definition table, a condition number that is a condition number, a condition item that indicates a condition item, and a condition content that indicates a condition content are defined in association with each other.

  The condition A is an example of a predetermined reliability condition regarding the reliability of the calculation result of the pulse rate, and “SNR (Signal to Noise ratio)> θ” of the pulse wave signal is defined as the condition content. That is, a condition indicating that the reliability of the calculation result of the pulse rate is determined based on the S / N ratio which is the signal-to-noise ratio of the pulse wave signal.

The SN ratio is calculated as follows, for example. Frequency decomposition processing is performed on the digitized pulse wave signal (pulse wave data). Then, the base line having the maximum spectrum value is selected, and the base line is set as the pulse base line indicating the pulse of the subject. Further, among the baselines excluding the baseline included in the predetermined range in the vicinity of the pulse baseline, for example, the baseline having the second largest spectrum value is selected as the noise baseline. The calculated spectral values of the pulse baseline and _{"P S",} the spectrum of the noise base line _{"P N"} and with an "SN ratio _{= P} S / P _N".

  In a situation where a base line with a large spectrum value is mixed and it is difficult to distinguish between a signal component and a noise component, the reliability of the pulse rate calculated based on the result of the frequency decomposition processing is lowered. In such a situation, the S / N ratio of the pulse wave signal tends to be small. Therefore, a threshold value “θ” for the SN ratio is set, and when the SN ratio exceeds the threshold value “θ”, it is determined that the reliability of the calculation result of the pulse rate is high.

  Condition B is a condition related to the possibility of a body motion component, and it is defined as “there is no periodic body motion frequency satisfying | pulse frequency−periodic body motion frequency | <φ” as the condition content. “Φ” is a threshold value of the frequency difference. This condition is an example of a predetermined frequency condition indicating that the frequency of the periodic body movement and the frequency of the calculated pulse rate are not approximate. When this frequency condition is satisfied, it can be determined that the calculated pulse rate is unlikely to capture the body motion component of the subject.

  The pulse wave signal is a signal in which the pulse component signal of the subject and the body motion noise component signal are superimposed. For this reason, there is a possibility that the frequency of the periodic body motion of the subject (hereinafter referred to as “periodic body motion frequency”) may be regarded as the pulse frequency. More specifically, since the pulsometer 1 is attached to the subject's arm, the frequency corresponding to the subject's pitch (step) is set as the periodic body motion frequency by the subject's periodic arm swing. Detected. Therefore, the fact that there is no periodic body motion frequency that satisfies a predetermined approximate condition with the pulse frequency is determined as a frequency condition for suitability determination.

  The body motion signal detected by the body motion sensor 20 is subjected to frequency decomposition processing, and the baseline serving as a reference wave for the motion is determined from the frequency (peak frequency) of the baseline at which the spectrum value is maximized. Determine the frequency. When the frequency decomposition process is performed, a baseline having a high spectral value tends to appear at a frequency (harmonic frequency) that is an integral multiple of the frequency of the reference wave. Therefore, it is effective to detect the harmonic frequency of the reference wave frequency as the periodic body motion frequency and perform the determination of the condition B for the plurality of periodic body motion frequencies.

  The condition C is a condition related to the consistency between the body motion state and the calculated pulse rate. As the condition content, the condition C1 “exercise state... Calculated pulse rate> HR1” is defined, and the condition C2 “quiet state /・ ・ Calculated pulse rate <HR2 ”is defined. “HR1” is a threshold value of the calculated pulse rate in the exercise state, and “HR2” is a threshold value of the calculated pulse rate in the calm state. These conditions are an example of matching conditions between the body motion state and the calculated pulse rate. Only one of the conditions C1 and C2 may be determined as the matching condition.

  The body motion state is a state of motion related to the subject's body, and includes, for example, a state of calm and exercise. The body motion state can be determined based on the detection result of the body motion sensor 20. For example, when the output of the acceleration sensor exceeds a predetermined threshold, it can be determined that the subject is in an exercise state.

  If the subject is in an exercise state, usually the subject's pulse rate should be high to some extent. Nevertheless, if the calculated pulse rate is lower than expected, the calculated pulse rate is likely to be incorrect. If the subject is in a calm state, the subject's pulse rate should normally be a low value to some extent. Nevertheless, if the calculated pulse rate is higher than expected, the calculated pulse rate is likely to be incorrect. Therefore, whether or not there is a contradiction in the correlation between the physical motion state of the subject and the calculated pulse rate is determined according to the above conditions.

  The condition D is a condition related to the continuity of the reliability condition, and the condition content is defined as “the number of continuations where the condition A is satisfied within the past predetermined time> N”. If the “SNR of pulse wave signal> θ” of condition A is continuously established for a predetermined time, it is determined that the calculated pulse rate is a reliable value.

  FIG. 6 is an explanatory diagram for determining the suitability of the calculated pulse rate, and illustrates a suitability determination table for use in determining the suitability of the calculated pulse rate. In the suitability determination table, a pulse range, an SN ratio threshold that is a threshold for the SN ratio, and an appropriate determination criterion that is a criterion for determining that the calculated pulse rate is appropriate are defined in association with each other.

  In the pulse range, the first to fourth pulse ranges described in FIG. 4 are defined. The S / N ratio threshold value is a threshold value of the reliability condition for the S / N ratio of the pulse wave signal defined in the condition A of FIG. 5, and a different value is determined according to the pulse range. Specifically, a smaller value is determined as the pulse range is closer to the reference pulse rate. However, the SN ratio threshold is exceptionally not defined in the first pulse range. This is because when the calculated pulse rate is included in the first pulse range, it is unconditionally determined to be appropriate.

  For the other pulse ranges, “θ2” is set for the second pulse range, “θ3” is set for the third pulse range, and “θ4” is set for the fourth pulse range, respectively. These magnitude relationships are “θ2 <θ3 <θ4”. According to the S / N ratio calculation formula described above, the greater the S / N ratio, the higher the quality of the pulse wave signal and the higher the reliability of the calculation result. Therefore, setting the SN ratio threshold value low means that the criteria satisfying the reliability condition are relaxed. That is, the reliability condition of the condition A is determined so that the calculated pulse rate is more easily determined as the degree of deviation between the reference pulse rate and the calculated pulse rate is smaller.

  The appropriate determination criterion is a criterion for determining that the calculated pulse rate is appropriate in the suitability determination. “Always” is defined for the first pulse range. That is, when the calculated pulse rate is included in the first pulse range, the calculated pulse rate is unconditionally determined to be appropriate.

  For the second pulse range, “condition A is satisfied” is defined. This means that the calculated pulse rate is determined to be appropriate when a condition regarding the reliability of the calculation result is satisfied.

  For the third pulse range, “(1) Condition A & B is met”, “(2) Condition A is met & Condition B is not met & Condition D is met”, or “(3) Condition A is met & Condition C is not satisfied & Condition D is satisfied ”. The fact that the calculated pulse rate is included in the third pulse range corresponds to the degree of divergence between the reference pulse rate and the calculated pulse rate satisfying a predetermined high divergence condition.

  (1) means that the calculated pulse rate is determined to be appropriate when both the reliability condition and the frequency condition are satisfied. (2) means that, when the reliability condition is satisfied but the frequency condition is not satisfied, the calculated pulse rate is determined to be appropriate if the condition regarding the continuity of the reliability condition is satisfied. This is based on the number of consecutive positive determinations performed by the reliability condition determination unit when the determination result of the reliability condition determination unit is affirmative and the determination result of the frequency condition determination unit is a negative determination. This corresponds to determining whether or not the number is appropriate.

  In (3), if the reliability condition is satisfied, but the matching condition between the body movement state and the calculated pulse rate is not satisfied, the calculated pulse rate is calculated if the condition regarding the continuity of the reliability condition is satisfied. This means that it is judged appropriate. This is because, when the determination result of the reliability condition determination unit is an affirmative determination and the determination result of the matching condition determination unit is a negative determination, the pulse calculated based on the number of consecutive positive determinations by the reliability condition determination unit This corresponds to determining whether or not the number is appropriate.

  For the fourth pulse range, it is determined that all the conditions A to D are satisfied. That is, unless all the conditions A to D are satisfied, the calculated pulse rate is determined to be inappropriate. In the fourth pulse range, since the degree of divergence between the reference pulse rate and the calculated pulse rate is the largest, the criteria for determining that the calculated pulse rate is appropriate are strictest.

3. Functional Configuration FIG. 7 is a block diagram illustrating an example of a functional configuration of the pulse meter 1. The pulsometer 1 includes a pulse wave sensor 10, a body motion sensor 20, a pulse wave signal amplification circuit unit 30, a pulse waveform shaping circuit unit 40, a body motion signal amplification circuit unit 50, and a body motion waveform shaping circuit unit 60. An A / D (Analog / Digital) conversion unit 70, a processing unit 100, an operation unit 200, a display unit 300, a notification unit 400, a communication unit 500, a clock unit 600, and a storage unit 700. It is prepared for.

  The pulse wave sensor 10 is a sensor that detects a pulse wave signal that captures the pulse wave of the subject to whom the pulse meter 1 is attached, and includes, for example, a photoelectric pulse wave sensor. The pulse wave sensor 10 detects a volume change caused by the inflow of blood flow into the body tissue as a pulse wave signal and outputs it to the pulse wave signal amplification circuit unit 30.

  The pulse wave signal amplification circuit unit 30 is an amplification circuit that amplifies the pulse wave signal input from the pulse wave sensor 10 with a predetermined gain. The pulse wave signal amplifier circuit unit 30 outputs the amplified pulse wave signal to the pulse waveform shaping circuit unit 40 and the A / D converter 70.

  The pulse waveform shaping circuit unit 40 is a circuit unit that shapes the pulse wave signal amplified by the pulse wave signal amplification circuit unit 30, and includes a circuit that removes a high-frequency noise component, a clipping circuit, and the like. The processing unit 100 determines whether or not a pulse wave has been detected based on the pulse waveform shaped by the pulse waveform shaping circuit unit 40.

  The body motion sensor 20 is a sensor that detects a body motion signal that captures the body motion of the subject to whom the pulsometer 1 is attached, and includes, for example, an acceleration sensor. The body motion sensor 20 corresponds to a body motion detection unit that detects the body motion of the subject.

  The body motion signal amplification circuit unit 50 is an amplification circuit that amplifies the body motion signal input from the body motion sensor 20 with a predetermined gain. The body motion signal amplification circuit unit 50 outputs the amplified body motion signal to the body motion waveform shaping circuit unit 60 and the A / D conversion unit 70.

  The body motion waveform shaping circuit unit 60 is a circuit unit that shapes the body motion signal amplified by the body motion signal amplification circuit unit 50. The body motion waveform shaping circuit unit 60 is a circuit that removes high-frequency noise components, a gravitational acceleration component, and other components. A circuit for determining whether or not, a clipping circuit, and the like. The processing unit 100 determines whether or not body motion is detected based on the body motion waveform shaped by the body motion waveform shaping circuit unit 60.

  The A / D conversion unit 70 converts the analog pulse wave signal amplified by the pulse wave signal amplification circuit unit 30 and the analog body motion signal amplified by the body motion signal amplification circuit unit 50 to predetermined amounts, respectively. It is sampled and digitized at sampling time intervals and converted to a digital signal. Then, the converted digital signal is output to the processing unit 100.

  The processing unit 100 is a control device and arithmetic device that comprehensively controls each unit of the pulse meter 1 according to various programs such as a system program stored in the storage unit 700, and is a CPU (Central Processing Unit) or DSP (Digital Signal). Processor). The processing unit 100 performs a pulse rate measurement process according to the pulse rate measurement program 710 stored in the storage unit 700, calculates and measures the pulse rate of the subject wearing the pulse meter 1, and causes the display unit 300 to display the pulse rate. Take control.

  The processing unit 100 includes, for example, a frequency analysis unit 110, a pulse rate calculation unit 120, a pulse rate difference calculation unit 130, an SN ratio calculation unit 140, a body movement state determination unit 150, and a pulse rate suitability determination unit 160. The display control unit 170 and the reference pulse rate update unit 180 are provided as functional units. However, these functional units are merely examples, and all the functional units do not necessarily have to be essential constituent requirements.

  The frequency analysis unit 110 performs a frequency decomposition process such as FFT on the pulse wave signal (pulse wave data) input from the A / D conversion unit 70 to acquire a frequency spectrum of the pulse wave signal. Further, frequency decomposition processing such as FFT is performed on the body motion signal (body motion data) input from the A / D conversion unit 70 to acquire the frequency spectrum of the body motion signal. The frequency analysis unit 110 corresponds to a body motion frequency determination unit that determines the frequency of the periodic body motion of the subject using the detection result of the body motion detection unit.

  The pulse rate calculation unit 120 detects a frequency spectrum corresponding to the pulse wave of the subject from the frequency spectrum of the pulse wave signal extracted by the frequency analysis unit 110, and calculates the pulse rate based on the frequency (or period). To do. The pulse rate calculation unit 120 corresponds to a pulse rate calculation unit that calculates the pulse rate of the subject.

  The pulse rate difference calculation unit 130 calculates a difference (pulse rate difference) between the reference pulse rate 780 stored in the storage unit 700 and the calculated pulse rate 770. The pulse rate difference calculation unit 130 corresponds to a divergence degree determination unit that determines a divergence degree between a given reference pulse rate and the calculated pulse rate calculated by the pulse rate calculation unit.

  The SN ratio calculation unit 140 calculates the SN ratio 750 of the pulse wave signal based on the frequency decomposition result of the pulse wave signal by the frequency analysis unit 110. The SN ratio calculation unit 140 corresponds to a reliability determination unit that determines the reliability of the calculation result of the pulse rate calculation unit.

  The body movement state determination unit 150 determines the body movement state of the subject based on the detection result of the body movement sensor 20. The body movement state determination unit 150 corresponds to a body movement state determination unit that determines the body movement state of the subject using the detection result of the body movement detection unit.

  The pulse rate suitability determination unit 160 is a suitability determination unit that refers to the pulse rate suitability determination data 720 stored in the storage unit 700 and determines the suitability of the calculated pulse rate 770 according to the above principle. Although illustration is omitted, the pulse rate suitability determination unit 160 determines whether or not a predetermined reliability condition that is determined so that the calculated pulse rate is determined to be more appropriate as the degree of divergence is smaller is determined. It has a judgment part. In addition, a frequency condition determination unit that determines whether or not a predetermined frequency condition indicating that the frequency of periodic body motion and the frequency of the calculated pulse rate are not approximated, and the body motion state and the calculated pulse rate Has a matching condition determining unit that determines whether or not a predetermined matching condition is satisfied.

  The display control unit 170 controls the display of the pulse rate on the display unit 300 based on the determination result of the pulse rate suitability determination unit 160. Specifically, when the calculated pulse rate 770 is determined to be appropriate by the pulse rate suitability determining unit 160, the calculated pulse rate 770 is displayed on the display unit 300 as a measured pulse rate (measurement result). On the other hand, if the calculated pulse rate 770 is determined to be inappropriate by the pulse rate suitability determining unit 160, the latest reference pulse rate 780 is displayed on the display unit 300 as the measured pulse rate (measurement result).

  The reference pulse rate updating unit 180 updates the reference pulse rate 780 with the calculated pulse rate 770 when the calculated pulse rate 770 is determined to be appropriate by the pulse rate suitability determining unit 160.

  The operation unit 200 is an input device having a button switch or the like, and outputs a signal of a pressed button to the processing unit 100. By operating the operation unit 200, various instructions such as a pulse rate measurement instruction are input. The operation unit 200 corresponds to the operation button 5 in FIG.

  The display unit 300 includes an LCD (Liquid Crystal Display) or the like, and is a display device that performs various displays based on a display signal input from the processing unit 100. Various kinds of biological information (pulse rate, exercise intensity, calorie consumption, etc.) are displayed on the display unit 300. The display unit 300 corresponds to the liquid crystal display 4 in FIG.

  The notification unit 400 includes a speaker, a piezoelectric vibrator, and the like, and is a notification device that performs various notifications based on a notification signal input from the processing unit 100. For example, various notifications are given to the subject by outputting an alarm sound from a speaker or vibrating a piezoelectric vibrator.

  The communication unit 500 is a communication device for transmitting / receiving information used inside the device to / from an external information processing device such as a personal computer (PC) under the control of the processing unit 100. As a communication method of the communication unit 500, a form of wired connection via a cable compliant with a predetermined communication standard, a form of connection via an intermediate device also used as a charger called a cradle, or short-range wireless communication is used. Various systems such as a wireless connection type can be applied.

  The clock unit 600 includes a crystal oscillator including a crystal resonator and an oscillation circuit, and is a time measuring device that measures time. The time measured by the clock unit 600 is output to the processing unit 100 as needed.

  The storage unit 700 is configured by a storage device such as a ROM (Read Only Memory), a flash ROM, or a RAM (Random Access Memory). The system program of the pulse meter 1, the pulse rate measurement function, the exercise intensity measurement function, and the calorie measurement function Various programs and data for realizing various functions are stored. In addition, it has a work area for temporarily storing data being processed and results of various processes.

  The storage unit 700 stores a pulse rate measurement program 710 executed as a pulse rate measurement process (see FIG. 8) by the processing unit 100 as a program. Further, the storage unit 700 calculates, as data, pulse rate suitability determination data 720, pulse wave signal frequency decomposition data 730, body motion signal frequency decomposition data 740, SN ratio 750, and SN ratio threshold 760. A pulse rate 770 and a reference pulse rate 780 are stored.

  The pulse rate suitability determination data 720 is data used by the pulse rate suitability determination unit 160 for determining the suitability of the calculated pulse rate 770. For example, data such as the condition definition table described in FIG. 5 and the suitability determination table described in FIG. 6 are included in this.

  The pulse wave signal frequency decomposition data 730 is data of a signal intensity value (spectrum value) for each frequency band acquired by the frequency analysis unit 110 performing frequency decomposition processing on the pulse wave signal. Similarly, the body motion signal frequency decomposition data 740 is data of a signal intensity value (spectrum value) for each frequency band acquired by the frequency analysis unit 110 performing frequency decomposition processing on the body motion signal.

4). Process Flow FIG. 8 is a flowchart showing the flow of the pulse rate measurement process executed in the pulse meter 1 when the processor 100 reads out the pulse rate measurement program 710 stored in the storage unit 700.

  First, the processing unit 100 performs initial setting (step A1). Specifically, for example, a predetermined value (for example, a pulse rate at rest) is set as an initial value of the reference pulse rate 780.

  Next, the processing unit 100 acquires detection results of the pulse wave sensor 10 and the body motion sensor 20 (step A3). Then, the frequency analysis unit 110 performs frequency decomposition processing on the pulse wave signal detected by the pulse wave sensor 10, and stores the result as pulse wave signal frequency decomposition data 730 in the storage unit 700 (step A5).

  Next, the pulse rate calculation unit 120 extracts the pulse frequency using the pulse wave signal frequency decomposition data 730 (step A7). Then, the pulse rate calculation unit 120 calculates the pulse rate of the subject based on the extracted pulse frequency, and updates the calculated pulse rate 770 of the storage unit 700 with the calculation result (step A9).

  The SN ratio calculation unit 140 calculates the SN ratio 750 of the pulse wave signal using the pulse wave signal frequency decomposition data 730 and stores it in the storage unit 700 (step A11). The body movement state determination unit 150 performs a body movement determination process for determining the body movement state of the subject based on the detection result of the body movement sensor 20 (step A13).

  Thereafter, the frequency analysis unit 110 performs frequency decomposition processing on the body motion signal detected by the body motion sensor 20, and stores the result in the storage unit 700 as body motion signal frequency decomposition data 740 (step A15). And the frequency analysis part 110 detects a periodic body motion frequency based on a frequency decomposition result (step A17).

  Thereafter, the pulse rate difference calculation unit 130 calculates a difference (pulse rate difference) between the reference pulse rate 780 and the calculated pulse rate 770 (step A19). Then, the processing unit 100 refers to the suitability determination table (see FIG. 6) included in the pulse rate suitability determination data 720, and sets the SN ratio threshold value 760 set in the pulse range corresponding to the calculated pulse rate difference. Set (step A21).

  Thereafter, the pulse rate suitability determination unit 160 performs a pulse rate suitability determination process for determining the suitability of the calculated pulse rate 770 (step A23). Specifically, referring to the condition definition table (see FIG. 5) and the suitability determination table (see FIG. 6) included in the pulse rate suitability determination data 720, the appropriate determination criteria set for the pulse range are satisfied. It is determined whether or not it has been done.

  If the appropriateness determination result is appropriate (step A25; appropriate), the display control unit 170 controls the display unit 300 to display the calculated pulse rate 770 as the measured pulse rate (step A27). Then, the reference pulse rate updating unit 180 updates the reference pulse rate 780 of the storage unit 700 with the calculated pulse rate 770 (step A29). On the other hand, if the suitability determination result is unsuitable (step A25; unsuitable), the display control unit 170 controls the display unit 300 to display the reference pulse rate 780 as the measured pulse rate (step A31).

  After step A29 or A31, the processing unit 100 determines whether or not to end the pulse rate measurement (step A33). For example, it is determined whether or not an instruction operation for ending pulse rate measurement has been performed by the subject via the operation unit 200. And when it determines with not complete | finishing a measurement (step A33; No), it returns to step A3. Moreover, when it determines with complete | finishing a measurement (step A33; Yes), a pulse rate measurement process is complete | finished.

5. Operational Effect In the pulse meter 1, the pulse rate calculation unit 120 calculates the pulse rate of the subject based on the detection result of the pulse wave sensor 10. Then, the pulse rate difference calculation unit 130 calculates a difference (pulse rate difference) between the reference pulse rate and the calculated pulse rate, and determines the degree of divergence between the reference pulse rate and the calculated pulse rate based on the pulse rate difference. . In addition, the SN ratio calculation unit 140 calculates the SN ratio of the pulse wave signal detected by the pulse wave sensor 10, and determines the reliability of the calculation result of the pulse rate calculation unit 120 based on the SN ratio. Then, the pulse rate suitability determination unit 160 calculates the pulse rate based on the pulse rate difference (degree of divergence) calculated by the pulse rate difference calculation unit 130 and the SN ratio (reliability) calculated by the SN ratio calculation unit 140. Judge the suitability of the.

  The pulse rate difference is a measure of how far the reference pulse rate is from the calculated pulse rate. Usually, the situation where the subject's pulse rate changes rapidly in a short time interval is rare. Therefore, the accuracy of the calculated pulse rate calculated by the pulse rate calculating unit 120 can be determined to some extent from the degree of deviation between the reference pulse rate and the calculated pulse rate. In addition, by referring to the SN ratio calculated by the SN ratio calculation unit 140 together, it is possible to correctly determine whether the calculated pulse rate is appropriate.

  The pulse rate suitability determination unit 160 is a predetermined value that is determined based on the pulse rate difference (degree of divergence) and the SN ratio (reliability) so that the smaller the pulse rate difference is, the easier it is to determine that the calculated pulse rate is appropriate. It is determined whether or not the reliability condition is satisfied. Specifically, the threshold for the S / N ratio is set lower as the pulse range has a smaller pulse rate difference. With this configuration, it is possible to determine whether the calculated pulse rate is appropriate according to a reliability condition that is optimized according to the degree of deviation between the reference pulse rate and the calculated pulse rate.

6). Modifications Embodiments to which the present invention can be applied are not limited to the above-described embodiments, and can be changed as appropriate without departing from the spirit of the present invention. Hereinafter, modified examples will be described.

6-1. Biological Information Processing Device In the above-described embodiment, a wristwatch type pulsometer has been described as an example of the biological information processing device, but a biological information processing device to which the present invention is applicable is not limited thereto. For example, the present invention can be applied to a finger-mounted pulse meter that is mounted on a fingertip and measures a pulse. Further, the pulse wave signal detection method is not limited to the detection method using light, and may be a detection method using ultrasonic waves or a detection method using electrocardiogram.

6-2. Body Motion Detection Unit In the above embodiment, the body motion sensor that is the body motion detection unit has been described as including an acceleration sensor. However, the body motion detection unit may include other sensors instead of the acceleration sensor. It is good. For example, the body motion sensor may be configured to include a gyro sensor, and the body motion of the subject may be detected based on the angular velocity detected by the gyro sensor. Of course, it may be configured to have both an acceleration sensor and a gyro sensor, and the body movement of the subject may be detected using the detection results of these sensors together.

6-3. Deviation degree Rather than determining the deviation degree between the reference pulse rate and the calculated pulse rate based on the difference between the reference pulse rate and the calculated pulse rate (pulse rate difference), for example, the ratio between the reference pulse rate and the calculated pulse rate You may determine based on (pulse rate ratio). That is, the divergence degree may be an index value that can determine the relative relationship between the reference pulse rate and the calculated pulse rate.

6-4. Appropriateness determination conditions The conditions defined in the condition definition table in FIG. 5 and the adequacy determination criteria defined in the suitability determination table in FIG. 6 are examples, and can be set as appropriate. For example, the suitability determination table of FIG. 6 may be determined as follows.

  FIG. 9 is a table configuration diagram of a second suitability determination table in the modification. In the second suitability determination table, “θ1” is defined as the SN ratio threshold value of the first pulse range, and “Condition A is satisfied” is defined as an appropriate determination criterion. “Θ2” is defined as the SN ratio threshold value of the second pulse range, and “(1) Condition A & B is satisfied” or “(2) Condition A is satisfied & Condition B is not satisfied & Condition D is set as an appropriate criterion. Is established. "

  Further, “θ3” is defined as the SN ratio threshold value of the third pulse range, and “(1) Condition A & B & C is satisfied” or “(2) Condition A & B is satisfied & Condition C is not satisfied” as an appropriate determination criterion. & "Condition D is satisfied" or "(3) Condition A & C is satisfied & Condition B is not satisfied & Condition D is satisfied" is defined. In addition, a value is not defined for the SN ratio threshold value in the fourth pulse range, and “no case for proper determination” is defined as an appropriate determination criterion.

  The magnitude relationship of the S / N ratio threshold is determined according to the same criteria as the first suitability determination table of FIG. That is, a smaller value is set as the SN ratio threshold value in the pulse range closer to the reference pulse rate so that the calculated pulse rate becomes easier to determine as the divergence degree between the reference pulse rate and the calculated pulse rate is smaller. Specifically, the magnitude relationship of the SN ratio threshold is “θ1 <θ2 <θ3”.

  Similarly to the first suitability determination table, an appropriate determination criterion is set so that the criterion for determining that the calculated pulse rate is appropriate becomes stricter as the degree of deviation between the reference pulse rate and the calculated pulse rate increases. Yes. In particular, for the fourth pulse range, a standard is set so that the calculated pulse rate is always determined to be inappropriate regardless of the success or failure of the conditions A to D.

  In the above-described embodiment, the case where the number of stages of the pulse range is set to four is illustrated, but how to determine the number of stages of the pulse range and the pulse range is a design matter and is not limited to the example of the above-described embodiment. Of course.

6-5. Reliability of Pulse Rate Calculation Result In the above embodiment, the reliability of the pulse rate calculation result is determined based on the signal-to-noise ratio (SN ratio) of the pulse wave signal detected by the pulse wave sensor 10. However, the SN ratio is only one index for determining reliability, and it is possible to determine reliability based on other indices.

  For example, the reliability of the calculation result may be determined based on the strength of the pulse wave signal. Specifically, if the amplitude of the pulse wave signal is extremely small, there is a high possibility that the pulse wave of the subject cannot be captured well, so it is determined that the reliability of the calculated pulse rate is low be able to. In addition, when the pulse wave signal suddenly swings out, there is a high possibility that noise is mixed in, so it can be determined that the reliability is low also in this case.

  In this case, for the condition A in the condition definition table of FIG. 5, for example, a condition corresponding to the signal intensity of the pulse wave signal can be determined as a condition relating to the reliability of the calculation result of the pulse rate. Further, the reliability condition may be determined as a condition combining the S / N ratio and the signal intensity of the pulse wave signal.

6-6. Reference Pulse Rate In the above embodiment, the latest calculated pulse rate determined to be appropriate by the suitability determination is set as the reference pulse rate. That is, when it was determined that the calculated pulse rate is appropriate, the process of updating the reference pulse rate with the calculated pulse rate has been described as being repeated at each calculation time.

  However, the pulse rate that can be set as the reference pulse rate is not limited to this. For example, an average value or a median value of calculated pulse rates determined to be appropriate in the past predetermined period (for example, a period corresponding to the past five calculation times) from the current calculation time may be obtained and set as the reference pulse rate.

  1 pulse meter, 10 pulse wave sensor, 20 body motion sensor, 30 pulse wave signal amplification circuit unit, 40 pulse waveform shaping circuit unit, 50 body motion signal amplification circuit unit, 60 body motion waveform shaping circuit unit, 70 A / D conversion Unit, 100 processing unit, 200 operation unit, 300 display unit, 400 notification unit, 500 communication unit, 600 clock unit, 700 storage unit

Claims (9)

A pulse rate calculator for calculating the pulse rate of the subject;
And given the reference pulse rate, and deviation degree determination section determines the degree of deviation between the calculated pulse rate calculated by the pulse rate calculating section,
A reliability determination unit for determining the reliability of the calculation result of the pulse rate calculation unit;
A suitability determination unit that determines the suitability of the calculated pulse rate based on the degree of divergence and the reliability ,
The reference pulse rate is set based on the pulse rate determined to be appropriate by the suitability determination unit in the past,
A biological information processing apparatus that sets a reliability determination criterion of the reliability determination unit based on a determination result of the divergence degree determination unit . The degree of divergence includes a first pulse range that represents the degree of divergence between the reference pulse rate and the calculated pulse rate, and a second pulse range that represents the degree of divergence greater than the degree of the first divergence. ,
The reliability determination criterion set based on the first pulse range is smaller than the reliability determination criterion set based on the second pulse range,
The biological information processing apparatus according to claim 1. When the degree of deviation between the reference pulse rate and the calculated pulse rate is in the second pulse range, the suitability determination unit determines the calculated pulse rate based on the number of consecutive positive determinations by the reliability condition determination unit. Determine suitability,
The biological information processing apparatus according to claim 2. A body motion detector for detecting the body motion of the subject;
A body motion frequency determination unit that determines the frequency of body motion of the subject using the detection result of the body motion detection unit;
Further comprising
The suitability determination unit includes a frequency condition determination unit that determines whether a frequency of the body motion and a frequency corresponding to the calculated pulse rate satisfy a predetermined frequency condition,
When the degree of deviation between the reference pulse rate and the calculated pulse rate is in the second pulse range, the calculated pulse rate using the determination result of the reliability condition determination unit and the determination result of the frequency condition determination unit To determine the suitability of
The biological information processing apparatus according to claim 2 or 3 . When the determination result of the reliability condition determination unit is an affirmative determination and the determination result of the frequency condition determination unit is a negative determination, the suitability determination unit continues the positive determination by the reliability condition determination unit. Determining the suitability of the calculated pulse rate based on the number of times;
Biological information processing apparatus according to any one of claims 2 to 4. A body motion detector for detecting the body motion of the subject;
A body movement state determination unit that determines a body movement state of the subject using a detection result of the body movement detection unit;
Further comprising
The suitability determination unit includes an alignment condition determination unit that determines whether or not the calculated pulse rate satisfies an alignment condition set based on the physical motion state, and the degree of divergence satisfies a predetermined high divergence condition In this case, the suitability of the calculated pulse rate is determined using the determination result of the reliability condition determination unit and the determination result of the matching condition determination unit.
The biological information processing apparatus according to claim 2 or 3 .   The matching condition is a threshold value relating to a pulse rate set according to the body movement state,
  The biological information processing apparatus according to claim 6. When the determination result of the reliability condition determination unit is an affirmative determination and the determination result of the matching condition determination unit is a negative determination, the suitability determination unit continues the positive determination by the reliability condition determination unit. Determining the suitability of the calculated pulse rate based on the number of times;
The biological information processing apparatus according to claim 6 or 7 . Calculating the subject's pulse rate;
Determining the degree of divergence between a given reference pulse rate and the calculated calculated pulse rate;
Determining the reliability of the calculation result of the pulse rate;
Determining the suitability of the calculated pulse rate based on the degree of divergence and the reliability ,
The reference pulse rate is set based on the pulse rate determined to be appropriate in the past by the determination of suitability,
Setting the reliability criterion based on the determination result of the degree of deviation,
A biological information processing method comprising:

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