CN112351735B

CN112351735B - Blood glucose level change measuring device

Info

Publication number: CN112351735B
Application number: CN201880095412.4A
Authority: CN
Inventors: 木暮一也
Original assignee: Tongsheng Electronic Development Co ltd
Current assignee: Tongsheng Electronic Development Co ltd
Priority date: 2018-07-20
Filing date: 2018-07-20
Publication date: 2024-01-30
Anticipated expiration: 2038-07-20
Also published as: CN112351735A; WO2020017028A1

Abstract

The present invention discloses a device for measuring the time-varying ascending and descending amount of a substance and the time-varying amount of the substance with high accuracy by light and displaying the result. The light of at least two light sources is irradiated to a sample containing a substance to be measured, fluctuation of components other than the substance to be measured is measured by the light of at least one light source, and fluctuation of the substance to be measured is measured by the light for measuring the substance to be measured. In order to measure the amount of change of the measured substance with high accuracy, the amount of change other than the measured substance is used as a correction value. Further, the measurement was performed 3 times at a predetermined time, the difference between the measurement value of the 1 st time and the measurement value of the 3 rd time was calculated, the time difference value of the difference between the measurement value of the 1 st time and the measurement value of the 2 nd time was calculated, and the time difference value of the measurement value of the 1 st time and the measurement value of the 3 rd time and the time difference value of the measurement value of the 1 st time and the measurement value of the 2 nd time were used as final results.

Description

Blood glucose level change measuring device

Technical Field

The present invention relates to a nondestructive measurement device for measuring, calculating, and displaying a relative change amount of an ascending and descending amount of a measured substance from a reference time and a time differential value of the change amount in a nondestructive manner.

Background

In the case of measuring the mass of a substance contained in a sample over time, particularly in the case where the time change is an important factor, it is desirable to measure the mass in a nondestructive manner. As one of the means for measuring in the nondestructive manner, there is a light-based measuring method such as spectroscopic analysis. One such suitable method is a non-invasive blood glucose level measurement technique. This is a technique for determining a blood glucose level from the amount of change in physical properties such as absorbance of light and polarized light, based on the concentration of the blood glucose level. As a representative method thereof, a plurality of methods based on near infrared spectroscopic analysis shown in fig. 1 have been reported in the past. This method is a method of measuring the mass (concentration) of a substance to be measured from the intensity distribution of a spectrum, but in order to identify the substance to be measured from the spectrum intensity distribution, a calibration line indicating the basic spectrum intensity distribution is required, and in order to create this calibration line, a method of efficiently creating by using a simulation technique or the like is proposed, but analysis of a large amount of measurement data is required.

In addition, this analysis method is mainly applied under specific conditions, and when it is applied to a plurality of unspecified samples, there is a problem in that it is very difficult. This is because the components other than the substance to be measured are different. It is almost impossible to widely apply the measurement due to physical variation, individual difference, and the like. The method based on this spectroscopic analysis is basically a method of measuring absorbance of light, but other methods using polarized light can be said to be the same. As a result, if the problem in measuring a substance that changes with time by passing light over time is carefully managed, the problem is attributed to reproducibility and measurement accuracy due to the generation of a calibration line, physical variation, and the like. It is difficult to realize a nondestructive measurement device for measuring a substance amount that changes with time by light over time.

Prior art literature

Patent literature

Patent document 1: japanese patent No. 3692751

Non-patent document 1: the adaptation of non-invasive blood component determination by infrared spectroscopy in 2003, IEEJ trans.eis.vol.127, no.5,686-691 (2007) (university of singapore)

Disclosure of Invention

Problems to be solved by the invention

The problem to be solved is that, although it is understood that the measured value varies with time due to light, the measurement accuracy is low due to the manufacturing accuracy and physical variation of the calibration line, and it is difficult to measure the mass (concentration) of the measured substance, and thus it is difficult to realize a non-destructive measurement device based on light.

Technical means for solving the problems

The present invention changes the thinking mode of measuring substances by light, and measures and calculates the relative change amount and time change amount of the measured substances from a certain moment to a certain moment without making a calibration line. The main feature is to use a method of measuring by using the light emitting portion as a point of application of pressure to the measurement site and adjusting the optical axis for measurement in real time.

Effects of the invention

The nondestructive measurement device of the present invention does not directly measure the mass (concentration) of the object to be measured, but can realize a light-based nondestructive measurement with good reproducibility as an index for substituting the mass (concentration) of the object to be measured.

The state in which the mass (concentration) of the substance to be measured has been rapidly increased, which has not been found by discrete measurement, can be detected by a nondestructive method.

Drawings

FIG. 1 shows an exemplary configuration of a nondestructive measurement device using spectral analysis.

Fig. 2 shows an example of changes in diet and blood glucose level.

Fig. 3 is a case of a shift action and a tilt action of the actuator lens.

Fig. 4 is an optical portion configuration when transmitted light is used.

Fig. 5 shows an optical section configuration when reflected light is used.

Fig. 6 is a configuration in which an optical unit is incorporated in the holding mechanism.

Fig. 7 is a circuit block diagram of the measurement device centering on the analog circuit.

Fig. 8 is a case of the LD 1-based adjustment period and the LD 2-based measurement period.

Fig. 9 is a circuit block diagram centering on the MPU-based digital processing.

Fig. 10 is a graph example showing dds values of the final measurement result from the measurement values.

Detailed Description

Example 1

Hereinafter, the case of applying to measurement of blood glucose level according to one embodiment of the present invention will be described with reference to the drawings. Of course, the present invention is not limited to blood glucose level, and can be applied to a case where measurement of a change in the substance to be measured with time is very important, for example, measurement of a change in photosynthesis of a plant.

Various methods have been proposed for measuring a blood glucose level by light in a nondestructive manner (hereinafter referred to as "non-invasive" in measuring a blood glucose level), and the determination is made by the absorbance and the diffusivity of light. Since it is known that the diffusivity is proportional to the concentration of the blood glucose level, the amount of light is measured using a photoelectric element (hereinafter, PD), but the sensitivity varies depending on the size (area) of the PD, and the size is equal to or larger than the optical path of the used light (the size is determined by the range of the assumed diffusivity). In this case, the light quantity detected by the PD is absorbed by blood sugar and reduced, and is diffused into the tissue (diffuser) by the blood sugar. Therefore, the light quantity detected by PD increases the absorbance by the diffusivity, and the quantity measured by PD increases the detection sensitivity of the change in blood glucose level. The measurement value obtained by overlapping the absorbance and the diffusivity is set as a basic measurement value. The absorbance was obtained from the detected amount. Further, since the absorbance changes depending on the temperature, the temperature of the measurement site is measured, and the temperature is corrected by correcting the value of the corrected temperature, thereby obtaining the final absorbance.

First, the nature of the blood glucose level was confirmed here. Blood glucose is one of the components in blood, but there are a plurality of substances having light absorption properties in the vicinity of a wavelength called near infrared rays, in addition to blood glucose. When the meal is taken, the blood glucose level increases after about 20 to 40 minutes after meal as a normal response change of the human body, and the blood glucose level is about 2 hours after meal due to the action of insulin or the like, which is about the same level as before meal, and it is estimated that substances that rapidly change in blood components due to the eating behavior are only the blood glucose level and the moisture. The reason for this is that substances other than blood glucose are components produced by internal organs or the like or components produced by reaction, and the change in blood glucose level is very slow compared to the change in blood glucose level until the components appear to change in blood. Therefore, the cause of the change in absorbance and diffusion can be almost determined as the blood glucose level in a short time of about 2 hours. Although there is a possibility that the change is blood glucose and moisture, moisture can be separated by observing absorbance of a light source having a wavelength different from the absorbance spectrum wavelength of blood glucose. That is, the amount of change in blood glucose level can be corrected by the difference in the light absorption sensitivity characteristic and the absorbance sensitivity of the blood glucose level due to moisture. However, 2 light sources must be coaxially observed. In order to perform the identification other than the blood glucose level, the blood glucose level cannot be identified without creating a calibration line based on a large amount of data, and the calibration line is no longer required because of such a change in the blood glucose level. Thus, the basic feature of the present device is to measure the amount of increase and decrease in blood glucose level. In addition, when the amount of change in the rise or fall of the blood glucose level is measured as in the current measurement, errors due to individual differences in skin pigment, skin state, and the like can cancel each other out, and thus measurement accuracy and reproducibility can be improved.

Under healthy conditions, the blood glucose level in a living body is approximately the same as that before meals about 2 hours after meals. However, in so-called diabetes mellitus, the amount of change is characteristic. Fig. 2 is a general example of time-dependent changes in blood glucose level.

Therefore, 3 measurements were performed before, about 30 minutes after and about 2 hours after meals, and judgment was made. This is similar to the glucose tolerance test of clinical diagnostic methods for diabetes. In addition, in the severe case (12 c), the blood glucose level may not change 30 minutes before, 30 minutes after and 2 hours after meals. Therefore, the time variation and the time differential value of the measured value are calculated, and a composite judgment of the variation and the time differential value in real time is performed.

In general, the measurement of blood glucose level by health diagnosis or the like is called fasting blood glucose level. Even if the measured value is slightly high, the leak severity may be observed. The response to the so-called latent diabetes may be a rapid increase in postprandial blood glucose level, and the symptom may be detected by a time-differentiated value thereof.

Next, a solution to the physical mutation will be described.

When light measurement is used, the change of the light path length causes errors and reduces the precision. Therefore, the optical path length must be limited to a certain position so as not to change, which is very inconvenient. In view of convenience, the method of measuring by reflected light is more preferable, but when the portion to which light is actually irradiated is changed, there is a possibility that subcutaneous tissue at the measurement portion is also changed, with a decrease in accuracy. In addition, the accuracy is also reduced due to the incident state of light, vibration, and the like. Therefore, as a structure of the measuring apparatus, a structure for restricting the measuring site is first adopted. This is a structure for holding, for example, earlobe, interphalangeal, etc. (fig. 6). In this way, the measurement will be performed at almost a constant location. In addition, the parts between the earlobe and the finger may be less susceptible to changes in pigment. Further, it is known that the absorbance also changes when the temperature changes, and it can be expected that a large temperature change does not occur in the grippable portion.

By adopting the clamping structure, the optical path length can be kept constant, and a constant pressure can be applied to the measurement site, which can suppress the change in blood flow. In the case of light measurement, the most affected is hemoglobin in blood, and the measurement accuracy is lowered due to the change in hemoglobin. This is because, in particular, the blood flow changes greatly after meals. Even if the measured site is limited to a certain extent, if a blood vessel exists in the subcutaneous tissue and the light path includes the blood vessel, the accuracy is expected to be lowered. Therefore, the optical path is reduced, and an actuator (not shown) is used (the same structure as an optical pickup such as a CD or DVD) to adjust the irradiation position of the spot so as to maximize the detection light. In addition, the mechanism has a mechanism for suppressing subconscious muscle movement and adjusting the incident state in real time, thereby ensuring the accuracy. Fig. 3 is an explanatory diagram of measurement by moving the actuator. However, even with this adjustment mechanism, there is an uncorrectable physical variation. Therefore, the blood glucose level is corrected by a light source of another wavelength using the same optical path, which is arranged coaxially with the light beam for measuring the blood glucose level, and the physical variation is corrected. It is considered that the physical variation is the same as the variation in the wavelength of measurement of the blood glucose level, and thus the physical variation may occur.

Fig. 4 is a basic optical configuration. The near infrared light source (semiconductor laser diode is used for the constitution) uses a plurality of different wavelengths, and the plurality of light sources are emitted coaxially. As the wavelength, a light source (measurement light: 23 a) having a wavelength near 1500nm, for example, a 2 nd wavelength light source (hereinafter referred to as LD 2) and a 1300nm light source (reference light: 23 b) having a 1 st wavelength light source (hereinafter referred to as LD 1) are used. The light source desirably employs a laser. The reason for this is that the emission wavelength range is very narrow and can be regarded as a single wavelength treatment. Of course, a light source having emission characteristics that vary by about 10nm in a single wavelength range may be used.

The reason why the wavelength around 1300nm is selected is that the light source is a light source having a wavelength that exhibits high absorbance to moisture but does not exhibit large absorbance to glucose, and the light source is combined and correction based on the detected amount of the measured light is performed as the amount of change and the physical change amount of the moisture amount based on the change in absorbance. The correction method may be a differential method or a ratiometric method. The actuator described later is electrically controlled so that the light quantity detected by the wavelength is maximized, based on the detected quantity of the reference light serving as a control quantity for performing vibration of the measurement site, correction of the incident light state, and avoidance of an obstacle on the optical path. Fig. 4 shows a configuration when transmitted light is used for the measurement site, and fig. 5 shows a configuration for detecting diffuse reflected light, all of which are detected in a state in which the irradiation light passes through the inside of the measurement site. Light from the light sources (23 a,23 b) is converged by lenses (24 a,24 b) into a small diameter beam of light, forming collimated light (14). The reason for converging the light beam into a small diameter is that the light source with a large output is not used, so that the brightness can be ensured, the power consumption can be suppressed, and the cost can be reduced. The actuator is provided with a function of correcting the position of the measurement site (21) by an actuator lens (22), and is capable of being displaced (16) and tilted (15) so as to perform real-time adjustment so that the detection value based on the reference light is maximized.

As a mechanism for holding the optical structure, a clamped structure is adopted. The reason for this is because the measurement site is restricted and the blood flow is restricted in the same manner as described above. Fig. 6 shows this structure, in which the above-described optical structure, i.e., the structures of fig. 4 and 5, are incorporated. In the case (27) of fig. 6, the light (14) from the light source is guided by the mirror (29), but a configuration (not shown) in which the light is guided to the actuator lens by an optical fiber or the like may be adopted. Although fig. 6 shows a configuration of transmitted light, the same mechanism may be used for diffuse reflection, and the optical configuration shown in fig. 5 may be incorporated. In this case, the focusing objective lens (20 b) disposed on the PD side of the structure that transmits light serves as a measurement object support member (26).

Fig. 7 is a basic circuit block diagram. Although fig. 7 shows a configuration using transmitted light, the same applies to a circuit using diffuse reflected light. The OSC1 (30 a) (not shown) is a signal for measurement, and is, for example, a signal that AC-modulates the light output at 1 Khz. The measurement value is the amplitude of the signal absorbed and diffused by the measurement site of the OSC1 (30 a) detected by the PD (17). OSC2 (30 b) is used to switch light source 1 (23 a) (hereinafter referred to as LD 1) and light source 2 (23 b) (hereinafter referred to as LD 2), and is switched by a light source switching circuit (31) so that LD2 is deactivated when LD1 emits light and LD1 is deactivated when LD2 emits light. For example, LD1 emits light when the output of OSC2 (30 b) is H, and LD2 emits light when it is L. LD1 is a reference light, and LD2 is a measurement light. The output of PD (17) (shared by reference light and measurement light) is IV-converted (35) and amplified by synchronous AMP (36). The light source driving circuits 1,2 (hereinafter referred to as LDD1, 2) (32 a,32 b) have a high-frequency superimposing function (34) on the laser diode, and are used in a single-mode to multi-mode oscillation mode so that the laser light emission by the reflected light is prevented from becoming unstable, and the light output is kept constant by APC circuits (not shown) such as front monitor and rear monitor diodes. In addition, a temperature sensor (34) is arranged to correct the temperature-induced changes. An RMS circuit (37) outputs the effective value of the detected signal and inputs the effective value to servo amplifiers (38, 40). A circuit (41 b) for holding the output of the RMS circuit (37) when the LD1 emits light and a servo circuit for inputting a reference voltage (39) (corresponding to the reference light quantity) to the LD1 servo amplifier and calculating the difference to automatically control the light emission quantity of the LD1 are formed. By this operation, the light quantity of the reference light received by the PD (17) is kept constant without the influence of the basic transmission quantity. The LD1 servo amplifier (38) calculates an input amount of the LDD1 (32 a), and when the output is large, it indicates that the attenuation amount of light in the measured object (21) is large, and the control amount of the LD1 becomes a reference value of the LD 2. The reference value automatically obtains the optical power required for basic measurement in the measured object (21). The detected LD1 amount is used as a reference for LD2 measurement light, and corresponds to a physical displacement and a displacement of the moisture amount of the measured object (21) being corrected. Since the physical displacement (variation in the structure of the object (21) to be measured) is considered to be the attenuation characteristic (the absorption characteristic and the diffusion characteristic are not affected) common to the LD1 and the LD2, the amount of physical displacement and the amount of correction of absorbance based on moisture that may possibly be displaced with time are reflected based on the detected amount of the LD 1. The difference between the value of the output of the circuit (41 c) holding the output of the RMS circuit (37) when the LD2 emits light and the value of the output of the circuit (41 a) holding the control amount of the LD1 is calculated, and the difference is used as the control output of the LD2, so that the output of the LD2 can be kept constant. An optimum value is obtained in advance (for the ratio of the light emission amount of LD1 to the light emission amount of LD2, and the gain of LDD is determined in accordance with the ratio). The output from the RMS circuit (37) of LD1 is held by the LD1 detection value holding circuit (41 b) when the output of OSC2 (30 b) is H, for example, and the output from the measurement value correction circuit (42) for calculating the difference between the LD2 detection holding circuit (41 c) and the control amount of LD2 when the output is L is finally a measurement value obtained by correcting the physical displacement and the displacement of moisture for the LD2 detection amount. In the present apparatus, the measurement was performed 3 times with a time lag. The method of obtaining the final result by the 3 measurements will be described later.

The actuator lens (22) is adjusted by the light emission period (49) of the LD 1. When the primary light is emitted, the center of the light beam is detected on which side by calculating the difference (43) between the outputs (17 s,17 b) of the secondary PD on the primary PD (17) side, and by this operation, the center of the intensity of the light detected by the PD becomes the center of the PD. In the configuration of fig. 7, when the output (35S) of S is large, the light intensity distribution detection circuit is configured to generate an output of (+) from the reference voltage, and the shift driving circuit (44B) is driven to reduce the output, and when the output (35B) of B is large, the output of (-) is generated from the reference voltage, and therefore, the shift driving circuit (44B) is driven to reduce the output in contrast to the signal of S (35S). The LD1 for measurement is driven simultaneously with the displacement driving mechanism (47), the LD1 detection amount is obtained, and then the LD 2-based detection is performed during the light emission period (50) of the LD2, thereby obtaining the final measurement value. Fig. 8 shows switching between LD1 and LD 2. In addition, in order to improve the SNR of the measured value, an average value (overlap value) is used. In this example, the modulated signal (30 c) is a continuous signal, but the same applies to pulses having a low duty cycle. When the actuator lens has a tilt function, first, control output is measured for a plurality of LD1 light emission periods (49) for reference light based on LD1 before measurement is entered, and output from a tilt drive reference voltage generation circuit (46) (which uses an extremely small-scale MPU or the like) is changed each time, a tilt drive mechanism (48) is driven, and after a state where LD1 control amount is minimized is obtained, adjustment and measurement cycle by the shift drive mechanism is entered. The present tilt drive mechanism (48) and displacement drive mechanism (47) provide real-time adjustment to eliminate the influence of the tissue structure at the measurement site and to correct the displacement caused by vibration or the like.

Example 2

Fig. 7 shows a configuration of an analog servo loop as a circuit, and it is needless to say that the circuit may be realized by digital processing by an MPU (52) or the like. Further, since the servo loop is simulated, the light emission of LD1 and LD2 is performed by the waveform (30 c) from the oscillator as shown in fig. 9, but even if the light emission is performed by the short pulse light emission (30 d) such as the pulse light emission of about 10ns to 30ns, the temperature rise of the measurement site due to the energy of the light can be avoided by the pulse light emission. By suppressing the temperature rise, improvement in measurement accuracy can be expected. In the case of blood glucose level, the human skin is a measurement site, and therefore, when very strong light is continuously irradiated, there is a possibility that the skin is scalded due to the light. The safety area of the human body with respect to the intensity (energy) of the light is determined according to a standard formulated according to international safety standards. The synchronous amplifier (36) may be realized by digital signal processing. As a result, the LD1 and LD2 control amounts of the servo loop themselves become detection amounts corresponding to the absorbance and the diffusivity. Fig. 9 shows a structure diagram at this time. First, a value (36 a) of the LD1 at the time of light emission (the light emission control amount is a predetermined amount) is input after analog-to-digital conversion, the driving amount of the tilt driving circuit (45 b) is changed, the driving amount that minimizes the detected amount of the LD1 is detected, and an optimal state of tilt is obtained, and in this state, adjustment by the shift driving mechanism (47) is performed, so that signals (35 s,35 b) from the sub PD are input to the MPU (52) after analog-to-digital conversion, and an operation (corresponding to an operation of the light intensity distribution detecting circuit (43)) is performed in the MPU (52), and the shift driving circuit (44 b) is driven so that the PD (17) becomes the center of the light beam. The series of tilt control and shift control is performed before the measurement of LD1 and LD 2. When LD1 and LD2 are driven, LD1 and LD2 are driven from the MPU (52), but the modulation by OSC1 (30 a) is equivalent to control of LD1 on/off signal (32 d) and LD2 on/off signal (32 e). In measurement, first, the LD1 emission control amount (32 c) is adjusted by setting the output from the MPU to a constant amount, and a detection amount is obtained so that the value (36 a) input from the analog-to-digital conversion becomes a predetermined value (corresponding to the LD1 reference voltage generation circuit (39)), and the detection value is taken as the LD1 detection value. Then, similarly, the LD2 emission control amount (32 f) is adjusted so that the value input to the MPU (36 a) after analog-to-digital conversion becomes a predetermined amount based on the amount detected by the LD 1. The LD2 light emission control amount (32 f) at this time is set to a detection amount based on LD 2. Then, the MPU (52) subtracts the LD 1-based detection amount from the LD 2-based detection amount and corrects the result by using a signal (33 a) from a temperature correction sensor (33) (the correction amount is obtained by experiment based on the value obtained by the absorbance characteristic based on temperature), and the result is the final measurement value. With this configuration, the blood glucose level to be measured can be assumed to be in the range of 50mg/dl to 200 mg/dl. In SMBG, which is practically used for the treatment of diabetes, it is required to be in the range of about 0mg/dl to 900 mg/dl. If this range is assumed, a considerable laser output may be required, but by narrowing the range, low power consumption and reduced cost can be achieved.

The processing of the measurement values of the characteristics of the present apparatus 3 times and the output of the final result will be described below according to the operation of the specific apparatus. First, a pre-meal operation switch (54 a) is operated to measure a pre-meal value. The measurement value at this time is set to (t 1, S1). Then, when about 30 minutes after meal passes, the post-meal operation switch (54 b) is operated to perform measurement. The measurement value at this time is set to (t 2, S2). Further, when about 2 hours have elapsed, the measurement was performed by operating the switch operated after meal. The measurement value at this time is set to (t 3, S3). (determination after 30 minutes, 2 hours, etc., is performed by a timer (55) inside the apparatus), and ds=s3-S1 is obtained from the measured value. This value becomes the basic measurement quantity of the device. Next, dts= (s 2-s 1)/(t 2-t 1) was obtained. The value is a time differential value indicating how much the short time is changed, and the result of the judgment from the value of ds and the value of dts is displayed on a display (53) as a means. This value represents the rate of rise of the blood glucose level. It is known that the blood glucose level significantly varies depending on the metabolic state, the eating manner, and the content, and even if the blood glucose level is normal in the fasting state, the blood glucose level may be rapidly increased by eating. This rising blood glucose level is called a blood glucose level spike, and a case where the value of this spike is large is also called so-called latent diabetes. When the time differential value of this time is large, it is estimated that there is a large peak in blood glucose level. In the measurement of a normal blood glucose level, when detecting the peak of the blood glucose level, it is necessary to continuously measure the blood glucose level to measure the maximum value. In this embodiment, the continuous measurement is not required, and the measurement is equivalent to the measurement of the peak of the blood glucose level. In the present measurement method, the difference in measured value and the change rate are calculated in a short time, so that the deviation from the accuracy is offset, and the measurement accuracy and reproducibility are improved.

Fig. 10 is a graph for obtaining a final judgment value. The horizontal axis represents the value of ds (56), and the vertical axis represents the final measurement result dds (57). In this space, the curves correspond to dts (58). The ds, dts, dds characteristic shows that dds (57) becomes high when dts (57) is high even though ds (56) is low. For example, which dts (58) curve is selected by normalizing the dts value to a value around 20. (the dts curve is plotted by determining the actual blood glucose level as the product specification based on the medical examination standard)

When ds (56) and dts (58) correspond to the region shown in fig. 10 (59), there is a possibility that the measurement value is abnormal or that the measurement result is abnormal. In this case, the display 53 displays the dds (57) value and blinks, and the process of taking care of the measurement result is indicated. For example, ds values may be small when sugar metabolism is abnormal (severe). In addition, the dts value may also be small. This state corresponds to a situation where the blood glucose level is very high before meals, and the blood glucose level does not rise any further by eating. In addition, the setting of the area shown in (59) is assumed to be breakfast, lunch and supper, 3 kinds of charts are prepared, and which chart is selected can be determined based on the measured time period. For example, if the timer (55) is a morning time period, a considerable time may elapse since the diet of the previous day, and the blood glucose level may be lowered, and a graph corresponding to this time is used. The finally obtained dds value is displayed on a display, and the numerical value is displayed on the measuring device. Or alternatively displayed with a color gradient. The value and color are mapped (60), for example, with a value of dds of 0 as reference, shown as "blue" and the maximum as "red".

Industrial applicability

The present invention can be applied to diagnostic equipment for early detection of latent diabetes, which cannot be detected by measuring fasting blood glucose levels at present, by using a new health management index instead of blood glucose levels. In addition, the method of measuring the state of change, for example, by measuring the change in sugar produced by photosynthesis of plants can be applied to agricultural control equipment.

Description of symbols

1. Light source

2. Aperture diaphragm

3a objective lens (for coupling)

3b objective lens (for focusing)

4. Optical fiber

5. Object to be measured

6. Shutter device

7. Analytical grating

8. Reflecting mirror

9. Photoelectric element array

10 AD converter

11. Processor and method for controlling the same

12a time-variant of normal blood glucose level

Time-variant of 12b sugar metabolism abnormality

12c time-variant (severe) when sugar metabolism was abnormal

13. Blood vessels, etc

14. Light beam

15. Tilted actuator lens

16. Shifted actuator lens

17 PD (photoelectric element)

18. Optical path

19. Pressurizing

20a Objective lens for light emission

20b objective lens for focusing

21. Object to be measured

22. Actuator lens

23a light source 1

23b light source 2

24a collimator lens 1

24b collimator lens 2

25a PBS (for Synthesis)

25b PBS (for separating reflected light)

26. Object support member

27. Device frame

28. Fulcrum point

29. Reflecting mirror

17 sPD side pair PD(s)

17b PD side auxiliary PD (b)

30a OSC1 (Oscillator for Signal)

30b OSC2 (Signal Generator for light Source switching)

30c OSC1 output (light source modulation output)

30d LD1, LD2 pulse luminous waveform

31. Light source change-over switch

32a light source driving circuit 1 (LDD 1)

32b light source driving circuit 2 (LDD 2)

33. Temperature correction sensor

34. Multi-luminous oscillator

35 I/V conversion circuit

36. Synchronous amplifying circuit

37 RMS (effective value circuit)

38 LD1 servo amplifier

39 LD1 reference voltage generating circuit

40 LD2 servo amplifier

41a LD1 control amount holding circuit

41b LD1 luminescence detection value holding circuit

41c LD2 luminescence detection value holding circuit

42. Measurement value correction circuit

43. Light intensity distribution detection circuit

44a shift driving buffer circuit

44b shift driving circuit

45a tilting drive buffer circuit

45b tilting drive circuit

46 tilt drive reference voltage generating circuit

47. Displacement driving mechanism

48. Tilting drive mechanism

30 OSC1 output (light source modulation output)

49 Actuator lens adjustment mechanism during LD1 light emission

50 LD2 luminescence period (measurement period)

51 OSC2 output

32c LD1 luminescence control amount signal

32d LD1 on/off control signal

32e LD2 on/off control signal

32f LD2 light emission control quantity signal

33a temperature sensor signal

36a PD side auxiliary PD signal input

36b PD side auxiliary PD Signal input

52 MPU

53. Display device

54a operating switch (before meal)

54b operating switch (after meal)

55. Time-piece

56 ds calculation value

57 dds final measurement results

58 dts curve

59. Flicker to display blood glucose level

60 dds display color mapping

Claims

1. A blood glucose level change amount measuring device is provided with: a light source coaxially outputting a measurement light of a first wavelength composition in which glucose exhibits light absorption and a reference light of a second wavelength composition in which glucose exhibits light absorption lower than that of the first wavelength and moisture exhibits light absorption higher than that of the first wavelength;

a detector for detecting light of each wavelength reflected by the measurement site or light of each wavelength transmitted through the measurement site, which is output from the light source;

a measurement value correction unit for calculating a difference between the detection value of the measurement light obtained by the detector and the detection value of the reference light obtained by the detector,

the method is characterized in that the detection by the detector and the correction processing by the measurement value correction means are repeatedly performed with a time shift, at least a 1 st measurement value before meals, a 2 nd measurement value 30 minutes after meals, and a 3 rd measurement value 2 hours after meals are obtained, differentiation of the 1 st measurement value and the 2 nd measurement value is calculated, and the relative change amount between the 3 rd measurement value and the 1 st measurement value is calculated.

2. The blood glucose level change amount measurement device according to claim 1, further comprising: and a display device for displaying a final measurement result calculated from the differential value between the 1 st measurement value and the 2 nd measurement value and the relative change amount between the 3 rd measurement value and the 1 st measurement value.

3. The blood glucose level change amount measuring device according to claim 1 or 2, wherein,

the device comprises means for electrically correcting the irradiation position and angle of light to be irradiated onto a measurement site.

4. The blood glucose level change amount measuring device according to claim 1 or 2, wherein,

the blood glucose level measuring device has a structure in which a light emitting portion is used as a point of action for applying a predetermined pressure to a measurement target portion, and a blood glucose level in a state in which blood flow in the measurement target portion is suppressed is measured in a state in which the predetermined pressure is applied to the measurement target portion.

5. The blood glucose level change measuring apparatus according to claim 3, wherein,