JP2009039268A - Noninvasive biological information measuring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a noninvasive biological information measuring device for highly accurately estimating the feature quantity with low power consumption. <P>SOLUTION: The biological information measuring device comprises at least one light source 200; a control means 800 for controlling the light source 200; a biological information sensor 300 for measuring biological information; an amplifying means 400 for amplifying output signals from the biological information sensor 300; an analog-digital conversion means 500 for analog-digital converting the amplified signals; a storage means 600 for storing analog-digital converted digital data; and a feature quantity estimation means 700 for estimating the feature quantity of the biological information by analyzing the digital data in the storage means 600. The low power consumption can be achieved by changing the content of the control of the light source 200 according to the distance to an object to be measured obtained from the digital data. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a non-invasive living body information measuring apparatus capable of measuring living body information without invading the living body. More specifically, the irradiation condition of measuring light can be varied using a photoacoustic wave signal from the living body. The present invention relates to a possible noninvasive living body information measuring apparatus.

  The number of patients with diabetes, a typical lifestyle-related disease, is increasing worldwide. Diabetic patients require routine glycemic control to reduce complications from diabetes and improve the quality of life of patients. Therefore, patients must measure blood glucose regularly every day under the guidance of a doctor. As a typical method for measuring a blood glucose level, there is an invasive blood glucose measuring device that measures blood glucose level by collecting blood by inserting a patient's finger. A noninvasive blood glucose measurement device that does not require blood collection has been proposed because it involves labor and pain when blood is collected by puncturing a finger and there is a risk of infection and the like.

  As a non-invasive blood glucose measurement device, a “biological measurement system” using a photoacoustic effect is described. Light of a wavelength absorbed by glucose is irradiated from a biological measurement system onto a part of a living body such as a fingertip, and the irradiated light is focused on a relatively small focal region (for example, a blood vessel) in the living body. In general, light is absorbed by glucose and converted into kinetic energy in the tissue in the region adjacent to the focal region. Kinetic energy increases the temperature and pressure of the absorbing tissue region and generates sound waves. This sound wave is hereinafter referred to as “photoacoustic wave signal”. The photoacoustic wave signal is emitted from the absorbing tissue region and detected by an acoustic sensor included in the biological measurement system.

  The acoustic sensor is mounted in contact with the living body surface. The intensity of the photoacoustic wave signal is a function of glucose in the absorption tissue region, and the intensity measured by the acoustic sensor is used to check the blood glucose level (for example, Patent Document 1).

In such a system, when the blood vessel position in the living body changes, the distance between the blood vessel and the acoustic sensor is increased, so that the photoacoustic wave signal is attenuated, and the signal quality of the photoacoustic wave signal may be deteriorated. Therefore, a method is disclosed in which a plurality of channels of bioacoustic sensors are arranged in a plane and an optimal channel signal is selected from signals obtained from the plurality of bioacoustic sensors (for example, Patent Document 2).
Special table 2001-526557 gazette JP 2004-147940 A

  However, in the techniques described in Patent Document 1 and Patent Document 2, the photoacoustic wave obtained from a living body is very weak, so that the weak signal changes regardless of the distance between the blood vessel and the acoustic sensor. A sufficient amount of light that can be used to estimate the feature amount is output from the light source.

  For this reason, the above-described conventional apparatus has a problem that it requires a large amount of power consumption and is not suitable for practical use of a portable product.

  Conventionally, in order to minimize the influence of noise and the influence of body movement, measurement is performed a plurality of times, and a series of measurement results are averaged. Therefore, there is a problem that not only power consumption but also measurement time increases.

  The present invention has been made to solve the above-described conventional problems, and an object of the present invention is to provide a non-invasive living body information measurement apparatus that can reduce power consumption and shorten measurement time.

  In order to solve the conventional problem, a non-invasive living body information measuring apparatus according to claim 1 of the present invention is a photoacoustic wave from the living body that includes a feature amount of living body information by making light incident on the surface of the living body. In a non-invasive living body information measuring apparatus for detecting a signal from the surface of the living body, at least one light source, a control means for controlling the light amount and lighting timing of the light source and activation of each means described later, and measuring biological information for a predetermined time A living body information sensor, an amplifying means for amplifying an output signal from the living body information sensor, an A / D converting means for A / D converting the amplified signal, and storing the A / D converted digital data Storage means for analyzing the digital data stored in the storage means and estimating the feature quantity of the biological information. Extract the measurement position and the second measurement position, in which the control method of the light source in accordance with the time difference between the first measurement position to the second measurement position was and changes through the control means.

  A non-invasive living body information measuring device according to claim 2 of the present invention is the non-invasive living body information measuring device according to claim 1, characterized in that the light source control method is the light amount of the light source. is there.

A non-invasive living body information measuring apparatus according to claim 3 of the present invention is the non-invasive living body information measuring apparatus according to claim 1, wherein the light source control method is a lighting time of the light source. It is.
It is characterized by that.

  A non-invasive living body information measuring apparatus according to claim 4 of the present invention is the non-invasive living body information measuring apparatus according to any one of claims 2 to 3, wherein the feature amount estimating means is based on the first measuring position. Comparing the time difference to the second measurement position with at least one time difference threshold value that divides the time difference into two or more regions, and changing the control method of the light source according to the region. It is what.

  The noninvasive living body information measuring apparatus according to claim 5 of the present invention is the noninvasive living body information measuring apparatus according to claim 4, wherein the feature amount estimating means includes a writable register, The time difference threshold value can be changed from the outside.

  According to a sixth aspect of the present invention, there is provided a non-invasive living body information measuring apparatus that receives light from a living body from a surface of the living body by entering light on the surface of the living body and including a feature amount of living body information. In the noninvasive living body information measuring device to detect, at least one light source, a control means for controlling the light amount and lighting timing of the light source and activation of each means described later, a living body information sensor for measuring living body information for a predetermined time, and Amplifying means for amplifying an output signal from the biological information sensor, A / D converting means for A / D converting the amplified signal, storage means for storing the A / D converted digital data, and the storage A feature amount estimating means for analyzing the digital data stored in the means to estimate a feature amount of biological information, the feature amount estimating means extracting a second measurement position from the digital data, Is obtained is characterized in that the light source is changed through the control means a control method of the light source in accordance with the time difference from the lit to the second measurement position.

  A noninvasive living body information measuring apparatus according to claim 7 of the present invention is the noninvasive living body information measuring apparatus according to claim 6, wherein the light source control method is the light amount of the light source. It is.

  The noninvasive living body information measuring apparatus according to claim 8 of the present invention is the noninvasive living body information measuring apparatus according to claim 6, wherein the light source control method is a lighting time of the light source. Is.

  The noninvasive living body information measuring apparatus according to claim 9 of the present invention is the noninvasive living body information measuring apparatus according to any one of claims 7 to 8, wherein the feature amount estimating means is configured to turn on the light source. Comparing the time difference to the second measurement position with at least one time difference threshold value that divides the time difference into two or more regions, and changing the control method of the light source according to the region. It is a thing.

  The noninvasive living body information measuring apparatus according to claim 10 of the present invention is the noninvasive living body information measuring apparatus according to claim 9, wherein the feature amount estimating means includes a writable register, The time difference threshold value can be changed from the outside.

  A noninvasive living body information measuring apparatus according to an eleventh aspect of the present invention is configured to receive a photoacoustic wave signal from the living body including a feature amount of living body information by inputting light to the surface of the living body from the surface of the living body. In the noninvasive living body information measuring device to detect, at least one light source, a control means for controlling the light amount and lighting timing of the light source and activation of each means described later, a living body information sensor for measuring living body information for a predetermined time, and Amplifying means for amplifying an output signal from the biological information sensor, A / D converting means for A / D converting the amplified signal, storage means for storing the A / D converted digital data, and the light source Is repeated a predetermined number of times until the digital data is recorded in the storage means, and the digital data for a predetermined number of times stored in the storage means is averaged, A feature amount estimating unit that analyzes the averaged digital data to estimate a feature amount of biological information, and the feature amount estimating unit includes a first measurement position and a second measurement from the averaged digital data. The position is extracted, and the number of repetitions of the series of operations is changed according to the time difference from the first measurement position to the second measurement position.

  A non-invasive living body information measuring apparatus according to claim 12 of the present invention is the non-invasive living body information measuring apparatus according to claim 11, wherein the feature amount estimating means performs a second measurement from the first measuring position. The time difference to the position is compared with at least one time difference threshold value that divides the time difference into two or more regions, and the number of repetitions of the series of operations is changed according to the region. Is.

  A non-invasive living body information measuring apparatus according to claim 13 of the present invention is the non-invasive living body information measuring apparatus according to claim 12, wherein the feature amount estimating means includes a writable register, The time difference threshold value can be changed from the outside.

  According to a fourteenth aspect of the present invention, there is provided a non-invasive living body information measuring device that receives light from the living body from a surface of the living body by inputting light to the surface of the living body and including a feature amount of living body information. In the noninvasive living body information measuring device to detect, at least one light source, a control means for controlling the light amount and lighting timing of the light source and activation of each means described later, a living body information sensor for measuring living body information for a predetermined time, and Amplifying means for amplifying an output signal from the biological information sensor, A / D converting means for A / D converting the amplified signal, storage means for storing the A / D converted digital data, and the light source Is repeated a predetermined number of times until the digital data is recorded in the storage means, and the digital data for a predetermined number of times stored in the storage means is averaged, A feature amount estimating means for analyzing the averaged digital data to estimate a feature amount of biological information, the feature amount estimating means extracting a second measurement position from the averaged digital data, and The number of repetitions of the series of operations is changed according to the time difference from when the light source is turned on to the second measurement position.

  The noninvasive living body information measuring apparatus according to claim 15 of the present invention is the noninvasive living body information measuring apparatus according to claim 14, wherein the feature amount estimating means performs the second measurement after the light source is turned on. The time difference to the position is compared with at least one time difference threshold value that divides the time difference into two or more regions, and the number of repetitions of the series of operations is changed according to the region. Is.

  According to a sixteenth aspect of the present invention, in the noninvasive living body information measuring device according to the fifteenth aspect, the feature amount estimating means includes a writable register, and the register is configured by the register. The time difference threshold value can be changed from the outside.

  According to the noninvasive living body information measuring apparatus of the present invention, the first measurement position and the second measurement position are extracted from the data detected by the photoacoustic detection means, and the first measurement position to the second measurement position are extracted. By changing the amount of light from the next time or the number of measurements according to the time difference, it becomes possible to realize a measurement device with low power consumption and short measurement time, and improve the continuous measurement time when realized as a portable device Can do.

  Embodiments of the noninvasive living body information measuring apparatus of the present invention will be described below in detail with reference to the drawings.

(Embodiment 1)
In Embodiment 1 of the present invention, a noninvasive blood glucose measurement device 110 using a photoacoustic method is assumed as a noninvasive living body information measurement device.

  FIG. 1 is a diagram showing a system configuration according to Embodiment 1 of the present invention. In FIG. 1A, 110 is a non-invasive blood glucose measuring device, 120 is the surface of a living body, 111 is irradiation light, 130 is a blood vessel, and 131 is a photoacoustic wave signal. 1B is a start signal 803, FIG. 1C is a lighting timing 802, FIG. 1D is a photoacoustic wave signal 131, FIG. 1E is an end signal 804, and FIG. The estimated blood glucose level output timing is shown.

  FIG. 2 is a diagram showing a block configuration of the noninvasive blood glucose measurement device 110 according to Embodiment 1 of the present invention. In FIG. 2, reference numeral 110 denotes a noninvasive blood glucose measurement device. In this non-invasive blood glucose measurement device 110, 200 is a light source, 300 is a biological information sensor for measuring biological information, 400 is an amplification means for amplifying an output signal from the biological information sensor 300, and 500 is a signal amplified by the amplification means 400. A / D conversion means for A / D conversion, 600 for storage means for storing digital data A / D converted by the A / D conversion means 500, 700 for analyzing digital data stored in the storage means 600 The feature amount estimation means 800 for estimating the feature amount of the biological information is a control means 800 for controlling the light source 200 and the activation of the amplification means 400 and the A / D conversion means 500. Reference numeral 801 denotes a light amount, 301 denotes a voltage signal, 401 denotes an amplified signal, 501 denotes sampling data, 601 denotes stored data, 602 denotes a data transfer end pulse, 701 denotes an estimated blood sugar level, and 702 denotes a time difference signal.

  The control unit 800 includes a light source control content change unit 810 having a time difference determination unit 820 and a light amount change unit 830, and includes a time difference determination threshold register 821 provided inside the time difference determination unit 820 and a first light source provided inside the light amount change unit 830. By using the region light amount register 831 and the second region light amount register 832, the control unit 800 is controlled to change the light amount of the light source 200 according to the time difference signal 702 calculated by the feature amount estimation unit 700.

  FIG. 3 is a diagram showing a detailed block configuration of the feature quantity estimation means 700. In FIG. 3, reference numeral 710 denotes estimation means, 720 denotes a sample number counter, 730 denotes time window generation means, 740 denotes measurement position detection means, and 750 denotes time difference detection means. Reference numeral 721 denotes a sample number count signal, 731 denotes a time window signal, 736 denotes a counter stop signal, and 741 denotes a measurement position pulse.

  The estimation means 710 estimates a blood glucose level from the stored data 601 and the data transfer end pulse 602 and outputs the estimation result as an estimated blood glucose level 701. The sample number counter 720 counts the number of samples of the stored data 601 using the stored data 601, the end signal 804 and the counter stop signal 736, and outputs the count result as a sample number count signal 721.

  The time window generating means 730 includes a first time window register 732, a second time window register 733, a third time window register 734, and a fourth time window register 735, and according to the count value indicated by the sample number count signal 721. A time window signal 731 indicating opening / closing of the time window is output. The value indicated by the fourth time window register 735 is output to the sample number counter 720 as a counter stop signal 736.

  The measurement position detection means 740 detects the measurement position from the time window signal 731 and the stored data 601 and outputs the detection result as a measurement position pulse 741.

  The time difference detection means 750 detects the first measurement position and the second measurement position from the data transfer end pulse 602, the sample number count signal 721, and the measurement position pulse 741, respectively, and then the first measurement position and the second measurement position. A time difference between the positions is detected, and the detection result is output as a time difference signal 702.

  FIG. 4 is a timing chart in which the operation of the noninvasive blood sugar measurement device 110 according to Embodiment 1 of the present invention is plotted on the time axis. In FIG. 4, (b) is an activation signal 803, (e) is an end signal 804, (g) is stored data 601, (h) is a sample count signal 721, (i) is a time window signal 731, (j). Is a measurement position pulse 741, (k) is a data transfer end pulse 602, (l) is a time difference signal 702, and (f) is an estimated blood sugar level output timing.

  Further, a period from the generation of the activation signal 803 to the estimation of the blood glucose level is defined as a measurement basic cycle (10 seconds), and a series of blood glucose level estimation operations are performed every measurement cycle (3 minutes).

  Hereinafter, the operation when the noninvasive blood glucose measurement device 110 performs continuous blood glucose measurement will be described with reference to FIGS. 1, 2, 3, and 4. By mounting the non-invasive blood glucose measuring device 110 so as to be in contact with the surface 120 of the living body, the irradiation light 111 emitted from the light source 200 enters the living body. The incident irradiation light 111 propagates in the living body and is absorbed by a substance capable of estimating the blood glucose level in the blood vessel 130 to generate a photoacoustic wave signal 131. The photoacoustic wave signal 131 is detected by the biological information sensor 300, and the voltage signal 301 as a detection result is sent to the amplification unit 400.

  The amplification unit 400 amplifies the voltage signal 301 and outputs the amplified signal 401 to the A / D conversion unit 500. The A / D conversion means 500 samples the amplified signal 401 and outputs sampling data 501, and the storage means 600 stores the sampling data 501.

  When the feature amount estimation unit 700 receives the storage data 601 from the storage unit 600 and receives the data transfer end pulse 602 that informs the end timing of the data transfer from the storage unit 600, the feature amount estimation unit 700 estimates the blood glucose level and the estimation result is estimated blood glucose level. 701 is output.

  At this time, the first measurement position and the second measurement position are extracted from the storage data 601 received from the storage unit 600, the time difference between them is detected, and the detection result is output to the control unit 800 as a time difference signal 702. The control unit 800 activates and terminates the amplification unit 400 and the A / D conversion unit 500 and changes the control content of the light source 200 using the time difference signal 702.

  Below, it demonstrates using a specific numerical example. In the first embodiment, the measurement cycle is performed at intervals of 3 minutes. Also, the speed at which the photoacoustic wave propagates in the living body is 1500 m / s, the sampling frequency in the A / D conversion means 500 is 50 MHz, and the blood vessel 130 to be measured in the living body is 1 to the surface 120 of the living body due to individual differences. In this first embodiment, it is assumed that the blood vessel 130 is 1.5 mm deep with respect to the surface 120 of the living body.

  Here, the following values are set as initial values of the register that can be written from the outside.

That is,
(A) First time window register 732: 45 is set as the timing for opening the first time window in the time window generating means 730.
(B) Second time window register 733: 55 is set as the timing for closing the first time window in the time window generating means 730,
(C) Third time window register 734: 90 is set as the timing for opening the second time window in the time window generating means 730.
(D) Fourth time window register 735: 130 is set as the timing for closing the second time window in the time window generating means 730.
(E) Time difference determination threshold register 821: 60 is set as a threshold for light amount selection in the time difference determination means 820.
(F) First area light quantity register 831: 1.5 (μJ) is set as the light quantity value of the light quantity changing means 830 in the first area,
(G) Second area light quantity register 832: 1.0 (μJ) is set as the light quantity value of the area-specific light quantity changing means 830 in the second area.
Also, each signal other than the time difference signal 702 shown in FIG. 4 is initialized to 0, and the initial value of the time difference signal 702 is set to 100, which is larger than the value indicated by the time difference determination threshold register 821.

  After the above initial setting is completed, first, the noninvasive blood glucose measuring device 110 is mounted on the surface 120 of a living body such as a patient's arm as shown in FIG. Thereafter, when the patient activates a blood glucose level measurement start switch (not shown) provided in the noninvasive blood glucose measurement device 110, an activation signal 803 is output from the control unit 800 to the amplification unit 400 and the A / D conversion unit 500. Then, the amplification means 400 and the A / D conversion means 500 are activated (FIG. 4: T4A). The lighting timing 802 and the light quantity 801 of the light source 200 are controlled at the same timing when the amplification means 400 and the A / D conversion means 500 enter a stable operation, the light source 200 is turned on, and the photoacoustic wave signal 131 is generated.

  At this time, the initial value 100 of the time difference signal 702 is input to the time difference determination means 820, and this value is equal to or greater than the value 60 indicated by the time difference determination threshold register 821. Therefore, the light amount changing unit 830 selects the value indicated by the first region light amount register 831 and the light source 200 emits the irradiation light 111 having a light amount of 1.5 (μJ).

  This is because the depth of the blood vessel 130 with respect to the surface 120 of the living body is unknown at the time of the first measurement, and is assumed to be the deepest case.

  The photoacoustic wave signal 131 is converted into a voltage signal 301 corresponding to the pressure by the biological information sensor 300.

  The voltage signal 301 converted by the biological information sensor 300 is amplified by the amplification unit 400 with a preset gain, and is output to the A / D conversion unit 500 as an amplification signal 401.

  Here, the reason why the start signal 803 and the end signal 804 are input to the amplifying unit 400 is that an element such as an operational amplifier that is a constituent element of the amplifying unit 400 is operated only at the timing when the photoacoustic wave signal 131 is generated. Thus, the power consumption of the amplifying unit 400 is reduced. Therefore, it is possible to realize an equivalent operation regardless of these signals.

  An activation signal 803 from the control unit 800 activates the A / D conversion unit 500. The amplified signal 401 output from the amplifying unit 400 is A / D converted at a specific interval by the A / D converting unit 500, and sampling data 501 as the A / D conversion result is written in the storage unit 600.

  Here, the end signal 804 is input to the A / D conversion unit 500 only when the photoacoustic wave signal 131 is generated, such as an element such as an AD converter that is a component of the A / D conversion unit 500. Is intended to reduce the power consumption of the A / D conversion means 500. Therefore, it is possible to realize an equivalent operation regardless of this signal.

  When the end signal 804 from the control means 800 is received by the feature quantity estimation means 700 (FIG. 4: T4B), the stored data 601 recorded in the storage means 600 is read by the feature quantity estimation means 700. At this time, the sample number counter 720 is reset to 0 by the end signal 804 and then starts counting up every time the stored data 601 is sampled.

  In the usage method in the first embodiment, there are three peaks in the stored data 601. These are a peak (FIG. 4: T4C) generated when a part of the irradiation light 111 reaches the biological information sensor 300 immediately after the lighting timing of the light source 200, and a photoacoustic wave signal generated on the surface 120 of the living body. Peak that occurs after a delay time until 131 reaches the biological information sensor 300 (FIG. 4: T4E), peak that occurs after a delay time until the photoacoustic wave signal 131 generated from the blood vessel 130 reaches the biological information sensor 300 (FIG. 4: T4H).

  The approximate time at which these peaks occur is known from the relationship between the speed and distance of propagation of photoacoustic waves in the living body, so detecting each peak using a time window is effective in detecting peaks. Can be prevented.

  When the sample number count signal 721 reaches 45, which is the value indicated by the first time window register 732, the time window signal 731 changes from 0 to 1 (FIG. 4: T4D, the first time window opens), and the sample number count When the signal 721 reaches 55 which is the value indicated by the second time window register 733, the time window signal 731 changes from 1 to 0 (FIG. 4: T4F, the first time window is closed).

  The measurement position detection means 740 detects the peak position of the stored data 601 while the first time window is open, and generates the first measurement position pulse 741 at the sampling timing at which the peak is detected (FIG. 4: T4E). ).

  The time difference detection means 750 detects the value indicated by the sample number count signal 721 at the generation timing of the first measurement position pulse 741 as the first measurement position. The first measurement position at this time is 50.

  When the sample count signal 721 reaches 90, which is the value indicated by the third time window register 734, the time window signal 731 changes from 0 to 1 again (FIG. 4: T4G, the second time window opens), and the number of samples When the count signal 721 reaches 130, which is the value indicated by the fourth time window register 735, the time window signal 731 changes from 1 to 0 again (FIG. 4: T4I, the second time window is closed).

  The measurement position detection means 740 detects the peak position of the stored data 601 while the second time window is open, and generates the second measurement position pulse 741 at the sampling timing at which the peak is detected (FIG. 4: T4H). ).

  At this time, the time difference detection means 750 detects the value indicated by the sample number count signal 721 at the generation timing of the second measurement position pulse 741 as the second measurement position. The second measurement position at this time is set to 100.

  The sample number counter 720 stops counting up when the second time window is closed.

  When the transfer of the storage data 601 from the storage unit 600 to the feature amount estimation unit 700 is completed, a data transfer end pulse 602 is generated (FIG. 4: T4J).

  When the feature amount estimation means 700 receives the data transfer end pulse 602, the time difference detection means 750 causes the difference in count value between the first measurement position (FIG. 4: T4E) and the second measurement position (FIG. 4: T4H). (50 samples) is output as the time difference signal 702 (FIG. 4: T4K). At this time, the estimation means 710 starts estimating the blood glucose level.

  Here, the reason why the time difference signal 702 is 50 is as follows.

  When the distance L between the blood vessel 130 and the surface 120 of the living body is 1.5 mm and the speed v at which the photoacoustic wave propagates in the living body is 1500 m / s, the second measuring position is generated after the first measuring position is generated. The time difference t until the occurrence of t is t = L / v = 0.015 / 1500 = 1 μs. If the sampling frequency in the A / D conversion means 500 is 50 MHz, the sampling period is 20 ns. Therefore, if the time difference of 1 μs is converted into the number of sampling data in the stored data 601, 1 μs / 20 ns = 50 sample data numbers.

  When the estimation of the blood glucose level started by the data transfer end pulse 602 is completed, the estimated blood glucose level 701 is output from the estimation means 710 to the outside (FIG. 4: T4L).

  In the time difference determination means 820 provided inside the control means 800, the number of samples indicated by the time difference signal 702 is the value 60 indicated by the time difference determination threshold register 821 (the distance L between the blood vessel 130 and the surface 120 of the living body corresponds to 1.8 mm). Since it is smaller, the light quantity changing means 830 is instructed to select the value indicated by the second area light quantity register 832. As a result, the control means 800 reduces the amount of light in the next measurement cycle to 1.0 (μJ).

  The above operation is repeated every measurement cycle.

  In the first embodiment of the present invention, the time difference signal 702 is created using the number of samples from T4E to T4H in the stored data 601, but the same effect can be obtained by using the number of samples from T4C to T4H. This is because, in the non-invasive blood glucose measurement device 110 attached to the living body surface 120, the time for the photoacoustic wave signal 131 to propagate from the living body surface 120 to the living body information sensor 300 is caused by the constituent material and dimensions of the living body information sensor 300. This is because it is uniquely determined.

  However, when the contact pressure of the non-invasive blood glucose measurement device 110 with respect to the surface 120 of the living body changes, the T4E generation position may change slightly, so the width of the first time window opening varies with the T4E generation position. What is necessary is just to set in consideration of quantity.

  In this case, the timing for opening the first time window may be changed in advance by the first time window register 732 and the second time window register 733. Specifically, the stored data 601 generated immediately after the light source 200 is turned on. A time window having a width that can detect the peak (FIG. 4: T4C) is set, and the value of the time difference determination threshold register 821 is propagated until the photoacoustic wave signal 131 reaches the biological information sensor 300 from the blood vessel 130. What is necessary is just to set in consideration of time.

  As another method for generating the time difference signal 702, the lighting timing 802 output from the control unit 800 is input to the feature amount estimation unit 700, and the number of samples from the irradiation of the irradiation light 111 to the second measurement position is used. May be.

  In this case, the time window may be opened only at the timing set by the third time window register 734 and the fourth time window register 735.

  In the first embodiment of the present invention, the light amount of the light source 200 is changed. However, the same result can be obtained by changing the lighting time of the light source.

  In the first embodiment of the present invention, the estimated blood glucose level 701 is calculated by writing the sampling data 501 of the A / D conversion unit 500 into the storage unit 600 once and reading it by the feature amount estimation unit 700. The estimated blood glucose level 701 may be calculated by the feature quantity estimation unit 700 receiving the sampling data 501 directly from the A / D conversion unit 500.

  In the first embodiment of the present invention, the amount of light that can be changed by the light amount changing unit 830 is set to 1.5 (μJ) and 1.0 (μJ), but the number of threshold values in the time difference determination threshold register 821 By using a plurality of values, it is possible to set three or more light quantities.

  In the first embodiment of the present invention, it has been described that the blood vessel 130 exists at a depth of 1.0 mm to 2.25 mm from the surface 120 of the living body depending on the patient. However, the depth of the blood vessel 130 is limited to this. is not. By changing the opening timing of the second time window using the third time window register 734 and the fourth time window register 735, it is possible to arbitrarily detect the first measurement position and the second measurement position. is there.

  As described above, in the noninvasive blood glucose measurement device 110 described in the first embodiment of the present invention, it is possible to set the minimum necessary light amount for each irradiation cycle when the distance between the blood vessel 130 and the surface 120 of the living body changes. Therefore, it becomes possible to realize a measuring device with low power consumption.

  Note that the target to be measured by the noninvasive blood glucose measurement device 110 according to Embodiment 1 of the present invention is not limited to the amount of glucose in the blood vessel 130. That is, any substance that absorbs energy in the wavelength region of the irradiation light 111 and generates a photoacoustic wave may be used. For example, glucose contained in the tissue fluid between the surface 120 of the living body and the blood vessel 130, the amount of hemoglobin in the blood vessel 130, etc. It is applicable to.

(Embodiment 2)
In Embodiment 2 of the present invention, the noninvasive biological information measuring device is assumed to be a noninvasive blood glucose measuring device 140. In the second embodiment, in order to minimize the error of the estimated blood sugar level 701 due to the influence of body movement such as breathing and pulse and external noise, the measurement basic cycle is repeated a specified number of times at a cycle of about 10 μs to 100 ms. The estimated blood glucose level 701 is calculated as a measurement basic cycle, thereby reducing power consumption and the number of measurements.

  FIG. 5 is a diagram showing a system configuration according to Embodiment 2 of the present invention. In FIG. 5A, 140 is a non-invasive blood glucose measuring device, 120 is the surface of a living body, 111 is irradiation light, 130 is a blood vessel, and 131 is a photoacoustic wave signal. 5B is the start signal 803, FIG. 5C is the lighting timing 802, FIG. 5D is the photoacoustic wave signal 131, FIG. 5E is the end signal 804, and FIG. The estimated blood glucose level output timing is shown.

  FIG. 6 is a diagram showing a block configuration of the noninvasive blood glucose measurement device 140 according to Embodiment 2 of the present invention. In FIG. 6, reference numeral 140 denotes a noninvasive blood glucose measurement device. In this non-invasive blood glucose measurement device 140, 200 is a light source, 300 is a biological information sensor for measuring biological information, 400 is an amplification means for amplifying an output signal from the biological information sensor 300, and 500 is a signal amplified by the amplification means 400. A / D conversion means for A / D conversion, 600 for storage means for storing digital data A / D converted by the A / D conversion means 500, 700 for analyzing digital data stored in the storage means 600 805 is a control unit that controls the light source 200 and the activation of the amplification unit 400 and the A / D conversion unit 500. Reference numeral 801 denotes a light amount, 301 denotes a voltage signal, 401 denotes an amplified signal, 501 denotes sampling data, 601 denotes stored data, 602 denotes a data transfer end pulse, 701 denotes an estimated blood sugar level, and 702 denotes a time difference signal.

  The control unit 805 includes a light source control content change unit 811 having a time difference determination unit 820 and a repetition number change unit 840, and is provided inside the time difference determination threshold register 821 and the repetition number change unit 840 provided in the time difference determination unit 820. By using the first region repetition number register 841 and the second region repetition number register 842, the control unit 805 is configured to change the number of repetitions of a series of measurement operations according to the time difference signal 702 calculated by the feature amount estimation unit 700. Control.

  FIG. 7 is a diagram showing a detailed block configuration of the feature quantity estimation means 700. As shown in FIG. In FIG. 7, 760 is an averaging means, 710 is an estimation means, 720 is a sample number counter, 730 is a time window generation means, 740 is a measurement position detection means, and 750 is a time difference detection means. 721 is a sample count signal, 731 is a time window signal, 736 is a counter stop signal, 741 is a measurement position pulse, 761 is averaged storage data, 762 is an average end pulse, and 763 is an average data transfer end pulse. is there.

  The averaging means 760 averages the stored data 601 from the stored data 601, the data transfer end pulse 602 and the end signal 804, outputs the result as averaged stored data 761, and averages indicating the end timing of the averaging An average data transfer end pulse 763 indicating the timing at which the data transfer of the end pulse 762 and the average storage data 761 is completed is output.

  The estimation means 710 estimates a blood glucose level from the averaged storage data 761 and the averaged data transfer end pulse 763 and outputs the estimation result as an estimated blood glucose level 701.

  The sample number counter 720 counts the number of samples of the stored data 601 using the averaged storage data 761, the averaging end pulse 762, and the counter stop signal 736, and outputs the count result as a sample number count signal 721.

  The time window generating means 730 includes a first time window register 732, a second time window register 733, a third time window register 734, and a fourth time window register 735, and according to the count value indicated by the sample number count signal 721. A time window signal 731 indicating opening / closing of the time window is output. The value indicated by the fourth time window register 735 is output to the sample number counter 720 as a counter stop signal 736.

  The measurement position detection means 740 detects the measurement position from the time window signal 731 and the averaged storage data 761 and outputs the detection result as a measurement position pulse 741.

  The time difference detection means 750 detects the first measurement position and the second measurement position from the averaged data transfer end pulse 763, the sample number count signal 721, and the measurement position pulse 741, respectively, and then the first measurement position and the second measurement position. The time difference between the measurement positions is detected, and the detection result is output as a time difference signal 702.

  FIG. 8 is a timing chart in which the operation of the noninvasive blood glucose measurement device 140 according to Embodiment 2 of the present invention is plotted on the time axis. 8, (b) is an activation signal 803, (e) is an end signal 804, (m) is an averaging end pulse 762, (n) is averaged storage data 761, (h) is a sample count signal 721, (I) is a time window signal 731, (j) is a measurement position pulse 741, (o) is an averaged data transfer end pulse 763, (l) is a time difference signal 702, and (f) is an estimated blood glucose level output timing.

  In the repeated measurement, the generation interval of the activation signal 803 is measured by the measurement unit (0.1 seconds), and the interval from the generation of the activation signal 803 until the measurement unit is repeated a predetermined number of times to estimate the blood glucose level is the measurement basic cycle (10 seconds) As described above, a series of operations are performed every measurement cycle (3 minutes).

  Hereinafter, the operation when the noninvasive blood glucose measurement device 140 performs continuous blood glucose measurement will be described with reference to FIGS. 5, 6, 7, and 8.

  By mounting the non-invasive blood glucose measuring device 140 so as to be in contact with the surface 120 of the living body, the irradiation light 111 emitted from the light source 200 is incident on the living body. The incident irradiation light 111 propagates in the living body and is absorbed by a substance capable of estimating the blood glucose level in the blood vessel 130 to generate a photoacoustic wave signal 131.

  The photoacoustic wave signal 131 is detected by the biological information sensor 300, and the voltage signal 301 as a detection result is sent to the amplification unit 400.

  The amplifying unit 400 amplifies the voltage signal 301 and outputs the amplified signal 401 to the A / D conversion unit 500.

  The A / D conversion means 500 samples the amplified signal 401 and outputs sampling data 501, and the storage means 600 stores the sampling data 501.

  When the feature amount estimation unit 700 receives the storage data 601 from the storage unit 600 and receives the data transfer end pulse 602 that informs the end timing of the data transfer from the storage unit 600, the feature amount estimation unit 700 estimates the blood glucose level and the estimation result is estimated blood glucose level. 701 is output.

  At this time, the first measurement position and the second measurement position are extracted from the storage data 601 received from the storage unit 600, the time difference between them is detected, and the detection result is output to the control unit 805 as a time difference signal 702.

  The control unit 805 activates and terminates the amplification unit 400 and the A / D conversion unit 500 and changes the number of repetitions of a series of measurement operations using the time difference signal 702.

  Below, it demonstrates using a specific numerical example. In the present embodiment, it is assumed that the measurement cycle is performed at intervals of 3 minutes. Also, the speed at which the photoacoustic wave propagates in the living body is 1500 m / s, the sampling frequency in the A / D conversion means 500 is 50 MHz, and the blood vessel 130 to be measured in the living body is 1 to the surface 120 of the living body due to individual differences. In the present second embodiment, it is assumed that the blood vessel 130 is 1.5 mm deep with respect to the surface 120 of the living body.

  Here, the following values are set as initial values of the register that can be written from the outside.

That is,
(A) First time window register 732: 45 is set as the timing for opening the first time window in the time window generating means 730.
(B) Second time window register 733: 55 is set as the timing for closing the first time window in the time window generating means 730,
(C) Third time window register 734: 90 is set as the timing for opening the second time window in the time window generating means 730.
(D) Fourth time window register 735: 130 is set as the timing for closing the second time window in the time window generating means 730,
(E) Time difference determination threshold value register 821: 60 is set as a threshold value for selecting the number of repetitions in the time difference determination means 820.
(F) First area repetition number register 841: 150 is set as the number of repetitions in the first area.
(G) Second area repeat count register 842: 100 is set as the repeat count in the second area.
Further, each signal other than the time difference signal 702 shown in FIG. 8 is initialized to 0, and the initial value of the time difference signal 702 is set to 100 which is larger than the value indicated by the time difference determination threshold register 821.

  After the above initial setting is completed, first, the noninvasive blood glucose measuring device 140 is attached to the surface 120 of a living body such as a patient's arm as shown in FIG. Thereafter, when the patient activates a blood glucose level measurement start switch (not shown) provided in the noninvasive blood glucose measurement device 140, an activation signal 803 is output to the amplification unit 400 and the A / D conversion unit 500 by the control unit 805. Then, the amplification means 400 and the A / D conversion means 500 are activated (FIG. 8: T8A). The lighting timing 802 and the light quantity 801 of the light source 200 are controlled at the same timing when the amplification means 400 and the A / D conversion means 500 enter a stable operation, the light source 200 is turned on, and the photoacoustic wave signal 131 is generated.

  At this time, the initial value 100 of the time difference signal 702 is input to the time difference determination means 820, and this value is equal to or greater than the value 60 indicated by the time difference determination threshold register 821. Therefore, as the number of repetitions of the series of measurement operations, the number value indicated by the first area repetition number register 841 is selected, and the repetition is performed 150 times.

  This is because the depth of the blood vessel 130 with respect to the surface 120 of the living body is unknown at the time of the first measurement, and is assumed to be the deepest case.

  The photoacoustic wave signal 131 is converted into a voltage signal 301 corresponding to the pressure by the biological information sensor 300.

  The voltage signal 301 converted by the biological information sensor 300 is amplified by the amplification unit 400 with a preset gain, and is output to the A / D conversion unit 500 as an amplification signal 401.

  Here, the reason why the start signal 803 and the end signal 804 are input to the amplifying unit 400 is that an element such as an operational amplifier that is a constituent element of the amplifying unit 400 is operated only at the timing when the photoacoustic wave signal 131 is generated. Thus, the power consumption of the amplifying unit 400 is reduced. Therefore, it is possible to realize an equivalent operation regardless of these signals.

  An activation signal 803 from the control unit 805 activates the A / D conversion unit 500. The amplified signal 401 output from the amplifying unit 400 is A / D converted at a specific interval by the A / D converting unit 500, and the sampling data 501 as the A / D conversion result is written in the storage unit 600.

  Here, the end signal 804 is input to the A / D conversion unit 500 only when the photoacoustic wave signal 131 is generated, such as an element such as an AD converter that is a component of the A / D conversion unit 500. Is intended to reduce the power consumption of the A / D conversion means 500. Therefore, it is possible to realize an equivalent operation regardless of this signal.

  A series of processing from when the start signal 803 is output until the sampling data 501 is written in the storage unit 600 is repeated 150 times.

  When the 150th end signal 804 from the control unit 805 is received by the feature amount estimation unit 700 (FIG. 8: T8B), the storage data 601 recorded in the storage unit 600 is read by the feature amount estimation unit 700.

  When the averaging means 760 receives the end signal 804, the averaging means 760 starts the averaging operation of the stored data 601. When the data transfer end pulse 602 indicating that 150 times of stored data 601 has been transferred to the averaging means 760 is received, an averaged end pulse 762 is generated after averaging the stored data 601 (see FIG. 8: T8C).

  At this time, the sample number counter 720 is reset to 0 by the averaging end pulse 762 and then starts counting up every time the averaged storage data 761 is sampled.

  In the usage method in the second embodiment, there are three peaks in the averaged storage data 761. These are the peak (FIG. 8: T8D) generated when a part of the irradiation light 111 reaches the biological information sensor 300 immediately after the lighting timing of the light source 200, and the photoacoustic wave signal generated on the surface 120 of the living body. A peak that occurs after a delay time until 131 reaches the biological information sensor 300 (FIG. 8: T8F), and a peak that occurs after a delay time until the photoacoustic wave signal 131 generated from the blood vessel 130 reaches the biological information sensor 300. (FIG. 8: T8I).

  The approximate time at which these peaks occur is known from the relationship between the speed and distance of propagation of photoacoustic waves in the living body, so detecting each peak using a time window is effective in detecting peaks. Can be prevented.

  When the sample number count signal 721 reaches 45, which is the value indicated by the first time window register 732, the time window signal 731 changes from 0 to 1 (FIG. 8: T8E, the first time window opens), and the sample number count When the signal 721 reaches 55, which is the value indicated by the second time window register 733, the time window signal 731 changes from 1 to 0 (FIG. 8: T8G, the first time window is closed).

  The measurement position detection means 740 detects the peak position of the average storage data 761 while the first time window is open, and generates the first measurement position pulse 741 at the sampling timing at which the peak is detected (FIG. 8). : T8F).

  The time difference detection means 750 detects the value indicated by the sample number count signal 721 at the generation timing of the first measurement position pulse 741 as the first measurement position. The first measurement position at this time is 50.

  When the sample count signal 721 reaches 90, which is the value indicated by the third time window register 734, the time window signal 731 changes from 0 to 1 again (FIG. 8: T8H, the second time window opens), and the number of samples When the count signal 721 reaches 130, which is the value indicated by the fourth time window register 735, the time window signal 731 changes from 1 to 0 again (FIG. 8: T8J, the second time window is closed).

  The measurement position detection means 740 detects the peak position of the stored data 601 while the second time window is open, and generates the second measurement position pulse 741 at the sampling timing at which the peak is detected (FIG. 8: T81). ).

  At this time, the time difference detection means 750 detects the value indicated by the sample number count signal 721 at the generation timing of the second measurement position pulse 741 as the second measurement position. The second measurement position at this time is set to 100.

  The sample number counter 720 stops counting up when the second time window is closed.

  When the data transfer of the average storage data 761 from the averaging means 760 to the estimation means 710 is completed, an average data transfer end pulse 763 is generated (FIG. 8: T8K).

  When the feature quantity estimation means 700 receives the averaged data transfer end pulse 763, the time difference detection means 750 counts between the first measurement position (FIG. 8: T8F) and the second measurement position (FIG. 8: T8I). Is output as the time difference signal 702 (FIG. 8: T8L). At this time, the estimation means 710 starts estimating the blood glucose level.

  Here, the reason why the time difference signal 702 is 50 is as follows.

  When the distance L between the blood vessel 130 and the surface 120 of the living body is 1.5 mm and the speed v at which the photoacoustic wave propagates in the living body is 1500 m / s, the second measuring position is generated after the first measuring position is generated. The time difference t until the occurrence of t is t = L / v = 0.015 / 1500 = 1 μs. If the sampling frequency in the A / D conversion means 240 is 50 MHz, the sampling period is 20 ns. Therefore, when the time difference of 1 μs is converted into the number of sampling data in the stored data 601, 1 μs / 20 ns = 50 sample data numbers.

  When the estimation of the blood glucose level started by the averaged data transfer end pulse 763 is completed, the estimated blood glucose level 701 is output from the estimation means 710 to the outside (FIG. 8: T8M).

  In the repetition number changing means 840 provided inside the control means 805, the number of samples indicated by the time difference signal 702 is the value 60 indicated by the time difference determination threshold register 821 (the distance L between the blood vessel 130 and the surface 120 of the living body corresponds to 1.8 mm). ), The light quantity changing means 830 is instructed to select the value indicated by the second area repetition count register 842. As a result, the control means 805 sets the series of repetitions in the next measurement cycle to 100 times.

  The above operation is repeated every measurement cycle.

  In the second embodiment of the present invention, the time difference signal 702 is created using the number of samples from T8F to T8I in the averaged storage data 761, but the same effect can be obtained by using the number of samples from T8D to T8I. . This is because, in the non-invasive blood glucose measurement device 140 attached to the living body surface 120, the time for the photoacoustic wave signal 131 to propagate from the living body surface 120 to the living body information sensor 300 is caused by the constituent material and dimensions of the living body information sensor 300. This is because it is uniquely determined.

  However, when the contact pressure of the non-invasive blood glucose measuring device 140 with respect to the surface 120 of the living body changes, the T8F generation position may change slightly, so the first time window opening width varies with the T8F generation position. What is necessary is just to set in consideration of quantity.

  In this case, the timing for opening the first time window may be changed in advance by the first time window register 732 and the second time window register 733. Specifically, the stored data 601 generated immediately after the light source 200 is turned on. Is set to a time window that can detect the peak (FIG. 8: T8D), and the value of the time difference determination threshold register 821 is propagated until the photoacoustic wave signal 131 reaches the biological information sensor 300 from the blood vessel 130. What is necessary is just to set in consideration of time.

  As another method of creating the time difference signal 702, the lighting timing 802 output from the control unit 805 is input to the feature amount estimation unit 700, and the number of samples from the irradiation of the irradiation light 111 to the second measurement position is used. May be.

  In this case, the time window may be opened only at the timing set by the third time window register 734 and the fourth time window register 735.

  In the second embodiment of the present invention, the estimated blood glucose level 701 is calculated by writing the sampling data 501 of the A / D conversion unit 500 into the storage unit 600 once and reading it by the feature amount estimation unit 700. The estimated blood glucose level 701 may be calculated by the feature quantity estimation unit 700 receiving the sampling data 501 directly from the A / D conversion unit 500.

  In the second embodiment of the present invention, the number of repetitions that can be changed by the repetition number changing means 840 is two types of 100 and 150. However, by making the number of thresholds in the time difference determination threshold register 821 plural. Three or more repetitions can be set.

  In the second embodiment of the present invention, it has been described that the blood vessel 130 exists at a depth of 1.0 mm to 2.25 mm from the surface 120 of the living body depending on the patient. However, the depth of the blood vessel 130 is limited to this. is not. By changing the opening timing of the second time window using the third time window register 734 and the fourth time window register 735, it is possible to arbitrarily detect the first measurement position and the second measurement position. is there.

  As described above, in the noninvasive blood glucose measurement device 140 described in the second embodiment of the present invention, when the distance between the blood vessel 130 and the surface 120 of the living body changes, the minimum necessary number of repetitions can be set for each irradiation cycle. Therefore, a measurement device with low power consumption can be realized.

  Note that the target to be measured by the non-invasive blood glucose measurement device 140 in Embodiment 2 of the present invention is not limited to the amount of glucose in the blood vessel 130. That is, any substance that absorbs energy in the wavelength region of the irradiation light 111 and generates a photoacoustic wave may be used. For example, glucose contained in the tissue fluid between the surface 120 of the living body and the blood vessel 130, the amount of hemoglobin in the blood vessel 130, etc. It is applicable to.

  As described above, the noninvasive living body information measurement apparatus according to the present invention extracts the first measurement position and the second measurement position from the data detected by the photoacoustic detection means, and the second measurement position is extracted from the first measurement position. By changing the control method of the light source and the number of measurement repetitions according to the time difference to the measurement position, it is possible to realize a device with low power consumption and short measurement time, and continuous measurement of portable noninvasive biological information measurement equipment Useful for improving time.

The figure which shows the system configuration | structure in Embodiment 1 of this invention. The figure which shows the block configuration of the noninvasive blood-glucose measuring apparatus 110 in Embodiment 1 of this invention. The figure which shows the block structure of the feature-value estimation means 700 in Embodiment 1 of this invention. Timing chart showing operation of non-invasive blood glucose measurement device 110 according to Embodiment 1 of the present invention The figure which shows the system configuration | structure in Embodiment 2 of this invention. The figure which shows the block configuration of the noninvasive blood glucose measuring device 140 in Embodiment 2 of this invention. The figure which shows the block structure of the feature-value estimation means 700 in Embodiment 2 of this invention. Timing chart showing the operation of the non-invasive blood sugar measurement device 140 according to Embodiment 2 of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 110 Non-invasive blood glucose measuring device 111 Irradiation light 120 Living body surface 130 Blood vessel 131 Photoacoustic wave signal 140 Non-invasive blood glucose measuring device 200 Light source 300 Biological information sensor 301 Voltage signal 400 Amplifying means 401 Amplifying signal 500 A / D converting means 501 Sampling data 600 storage means 601 stored data 602 data transfer end pulse 700 feature quantity estimation means 701 estimated blood sugar level 702 time difference signal 710 estimation means 720 sample number counter 721 sample number count signal 730 time window generation means 731 time window signal 732 first time window register 733 Second time window register 734 Third time window register 735 Fourth time window register 736 Counter stop signal 740 Measurement position detection means 741 Measurement position pulse 750 Time difference detection means 760 Averaging Stage 761 Averaging stored data 762 Averaging end pulse 763 Averaging data transfer end pulse 800 Control means 801 Light quantity 802 Lighting timing 803 Start signal 804 End signal 805 Control means 810 Light source control content change means 811 Light source control content change means 820 Time difference determination Means 821 Time difference determination threshold value register 830 Light quantity change means 831 First area light quantity register 832 Second area light quantity register 840 Repeat count change means 841 First area repeat count register 842 Second area repeat count register

Claims (16)

In a non-invasive living body information measuring apparatus for detecting a photoacoustic wave signal from the living body containing light from a living body by entering light on the living body surface from the living body surface,
At least one light source;
Control means for controlling the light quantity and lighting timing of the light source and activation of each means described later;
A biological information sensor for measuring biological information for a predetermined time;
Amplifying means for amplifying an output signal from the biological information sensor;
A / D conversion means for A / D converting the amplified signal;
Storage means for storing the A / D converted digital data;
A feature amount estimating means for analyzing the digital data stored in the storage means and estimating a feature amount of biological information;
The feature amount estimation means extracts a first measurement position and a second measurement position from the digital data, and controls the control method of the light source according to a time difference from the first measurement position to the second measurement position. A noninvasive living body information measuring device characterized by changing through means. The noninvasive living body information measuring device according to claim 1, wherein the light source control method is a light amount of the light source. The noninvasive living body information measuring device according to claim 1, wherein the light source control method is a lighting time of the light source. The feature amount estimation means compares the time difference from the first measurement position to the second measurement position with at least one time difference threshold value that divides the time difference into two or more areas. The noninvasive living body information measuring device according to claim 2, wherein a control method of the light source is changed according to the method. 5. The noninvasive living body information measuring apparatus according to claim 4, wherein the feature amount estimating unit includes a writable register, and the time difference threshold value can be changed from the outside by the register. . In a non-invasive living body information measuring apparatus for detecting a photoacoustic wave signal from the living body containing light from a living body by entering light on the living body surface from the living body surface,
At least one light source;
Control means for controlling the light quantity and lighting timing of the light source and activation of each means described later;
A biological information sensor for measuring biological information for a predetermined time;
Amplifying means for amplifying an output signal from the biological information sensor;
A / D conversion means for A / D converting the amplified signal;
Storage means for storing the A / D converted digital data;
A feature amount estimating means for analyzing the digital data stored in the storage means and estimating a feature amount of biological information;
The feature amount estimation means extracts a second measurement position from the digital data, and changes the control method of the light source through the control means according to a time difference from when the light source is turned on to the second measurement position. A noninvasive living body information measuring device characterized by the above. The noninvasive living body information measuring device according to claim 6, wherein the light source control method is a light amount of the light source. The noninvasive living body information measuring device according to claim 6, wherein the light source control method is a lighting time of the light source. The feature amount estimating means compares the time difference from when the light source is turned on to the second measurement position with at least one time difference threshold value that divides the time difference into two or more regions, 9. The noninvasive living body information measuring apparatus according to claim 7, wherein a control method of the light source is changed accordingly. The non-invasive living body information measuring apparatus according to claim 9, wherein the feature amount estimation unit includes a writable register, and the time difference threshold value can be changed from the outside by the register. . In a non-invasive living body information measuring apparatus for detecting a photoacoustic wave signal from the living body containing light from a living body by entering light on the living body surface from the living body surface,
At least one light source;
Control means for controlling the light quantity and lighting timing of the light source and activation of each means described later;
A biological information sensor for measuring biological information for a predetermined time;
Amplifying means for amplifying an output signal from the biological information sensor;
A / D conversion means for A / D converting the amplified signal;
Storage means for storing the A / D converted digital data;
A series of operations from when the light source is turned on until the digital data is recorded in the storage means is repeated a predetermined number of times, the digital data for a predetermined number of times stored in the storage means is averaged, and the averaged digital A feature amount estimating means for analyzing the data and estimating the feature amount of the biological information,
The feature amount estimation unit extracts a first measurement position and a second measurement position from the averaged digital data, and the series of operations according to a time difference from the first measurement position to the second measurement position. The non-invasive living body information measuring device characterized by changing the number of times of repetition. The feature amount estimation means compares the time difference from the first measurement position to the second measurement position with at least one time difference threshold value that divides the time difference into two or more areas. The noninvasive living body information measuring device according to claim 11, wherein the number of repetitions of the series of operations is changed in accordance with. The non-invasive living body information measuring apparatus according to claim 12, wherein the feature amount estimating unit includes a writable register, and the time difference threshold value can be changed from the outside by the register. . In a non-invasive living body information measuring apparatus for detecting a photoacoustic wave signal from the living body containing light from a living body by entering light on the living body surface from the living body surface,
At least one light source;
Control means for controlling the light quantity and lighting timing of the light source and activation of each means described later;
A biological information sensor for measuring biological information for a predetermined time;
Amplifying means for amplifying an output signal from the biological information sensor;
A / D conversion means for A / D converting the amplified signal;
Storage means for storing the A / D converted digital data;
A series of operations from when the light source is turned on until the digital data is recorded in the storage means is repeated a predetermined number of times, the digital data for a predetermined number of times stored in the storage means is averaged, and the averaged digital A feature amount estimating means for analyzing the data and estimating the feature amount of the biological information,
The feature amount estimation unit extracts a second measurement position from the averaged digital data, and changes the number of repetitions of the series of operations according to a time difference from when the light source is turned on to the second measurement position. A non-invasive living body information measuring device characterized by that. The feature amount estimating means compares the time difference from when the light source is turned on to the second measurement position with at least one time difference threshold value that divides the time difference into two or more regions, The noninvasive living body information measuring device according to claim 14, wherein the number of repetitions of the series of operations is changed in accordance with. 16. The noninvasive living body information measuring apparatus according to claim 15, wherein the feature amount estimating means includes a writable register, and the time difference threshold value can be changed from the outside by the register. .

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