KR100694598B1 - Noninvasive in vivo measurement system for compensating effect of hemoglobin in blood glucose measuring - Google Patents

Abstract

A noninvasive vivo measuring system and a method for compensating an effect of hemoglobin in a blood sugar measurement are provided to measure a density of blood sugar correctly by removing influence of a density of Hb on the density of the blood sugar measured by an R-F(Raman-Fluorescence) method. A noninvasive vivo measuring system for compensating an effect of hemoglobin in a blood sugar measurement includes a tissue modulation unit(310), a hemoglobin measuring unit(330), and an R-F measuring unit(320). The tissue modulation unit(310) applies a pressure to a tissue. The hemoglobin measuring unit(330) measures a density of hemoglobin of the tissue by analyzing absorption of a predetermined electromagnetic wave at a first region of the tissue before and after the pressure is applied in the tissue modulation unit(310). The R-F measuring unit(320) measures blood-sugar density by analyzing a Raman spectrum from reflection of a laser illuminated on a second region of the tissue twice, before and after the pressure is applied to the tissue modulation unit(310). The R-F measuring unit(320) calculates a final blood sugar quantity by compensating the measured density of the blood sugar according to the density of the measured hemoglobin.

Description

Noninvasive in Vivo Measurement System for Compensating Effect of Hemoglobin in Blood Glucose Measuring}

1 is a view for explaining a blood glucose measurement through a general tissue modulation.

2 is a graph showing the general relationship between the amount of Hb and blood glucose.

3 is a diagram illustrating a non-invasive biometric measurement system according to an embodiment of the present invention.

4 is a view for explaining in detail the R-F measurement unit of FIG.

5 is a flowchart for describing an operation of the non-invasive biometric system of FIG. 4.

6 shows the removal of blood from blood vessels upon application of pressure in tissue modulation.

7 is a view for explaining the components of the blood in the blood vessels.

8 is a graph for explaining the relationship between the wavelength and the Raman scattering intensity in the R-F method for blood glucose calculation.

9 is a graph for explaining the relationship between the wavelength and the Hb absorption coefficient.

<Explanation of symbols for the main parts of the drawings>

310: tissue modulation unit

320: R-F (Raman-Fluorecsence) measuring unit

330: Hb (Hemoglobin) measuring unit

331: light source array

332: light sensor

333: concentration calculation unit

The present invention relates to a blood glucose measurement system, and more particularly to a non-invasive biometric system and method capable of accurate blood glucose measurement through concentration compensation of Hb (Hemoglobin: hemoglobin).

Today, improved living conditions have led to an increase in adult disease, which has resulted in higher health concerns than before. In particular, there is an increasing number of patients with diabetes, one of the adult diseases. Diabetes releases glucose into the urine due to a higher concentration of glucose (blood sugar) in the blood due to a lack of insulin in the body, and these diabetics check blood sugar about 6 times a day for necessary insulin administration. . Blood glucose is one of the most important factors to inform the health status, normal people 70 ~ 110mg / dℓ (mg amount of 100cm ³ sugar), and 180mg / dℓ or less after eating, 60mg / dℓ or more even on an empty stomach. However, when blood sugar levels rise above the normal level, dehydration such as severe thirst and urinary symptoms occur, and when it falls below the normal level, symptoms of anxiety and dizziness occur. Falling or severe cases can lead to death.

Invasive methods for measuring blood glucose concentrations of the collected blood by an enzymatic method or the like have been widely used. Today, non-invasive blood glucose measurement methods have been developed and used in part to increase user convenience.

In the blood glucose measurement method using tissue modulation, one of the non-invasive blood glucose measurement methods, as shown in FIG. 1, when a laser beam irradiated to a finger is reflected, a Raman-Fluorecsence (RF) spectrum analysis of the reflected laser is performed. I use it. That is, a phenomenon in which the Raman-specific wavelength change spectrum is different depending on the molecules present in the blood is used.

In this manner, known as Raman-Fluorecsence (R-F), blood glucose can be predicted by analyzing Raman spectra scattered with respect to glucose components in blood vessels in the fluorescence spectrum of the reflected laser and appearing at a corresponding wavelength. This is also shown in US Pat. No. 6,289,230.

However, since the intensity of the Raman spectrum with respect to the glucose component is influenced by other components in the blood, in the conventional RF method through tissue modulation as described above, the blood glucose level cannot be constantly measured according to the amount of other components in the blood. There is a problem. In particular, as shown in FIG. 2, blood glucose levels appear randomly according to the amount of Hb in the blood.

Accordingly, an object of the present invention is to provide a non-invasive biometric system that compensates for the effects of Hb in order to improve the accuracy of blood glucose measurement.

Another object of the present invention is to provide a non-invasive biometric method of correcting the blood glucose concentration measured by the R-F method by measuring the Hb concentration.

Non-invasive biometric system according to the present invention for achieving the object of the present invention as described above, the tissue modulation unit for applying a pressure to the tissue; A Hb (Hemoglobin) measurement unit for measuring the Hb concentration of the tissue by analyzing the degree of absorption of the predetermined electromagnetic waves in the first portion of the tissue before and after applying the pressure in the tissue modulation unit; And measuring blood glucose concentration by analyzing Raman spectra from the reflection of the laser irradiated to the second portion of the tissue before and after applying the pressure in the tissue modulation unit, and correcting the measured blood glucose concentration according to the measured Hb concentration. Raman-Fluorecsence (RF) measurement unit for calculating the final blood glucose level is included.

The Hb measuring unit analyzes the absorption difference of the electromagnetic waves of at least two wavelengths before and after applying the pressure to calculate Hb concentration, and the wavelength of the electromagnetic waves used before and after applying the pressure is 1300 nm or less.

The R-F measuring unit generates the final blood glucose level by correcting the blood glucose concentration measured from the Raman spectrum according to the degree of the Hb concentration greater or smaller than the threshold value, either large or small.

The tissue modulation unit may apply a predetermined pressure set between a mechanism for contacting the tissue and a predetermined portion of the tissue.

The non-invasive biometric method according to the present invention for achieving the object of the present invention comprises the steps of measuring the Hb concentration of the tissue by analyzing the degree of absorption of electromagnetic waves in the first portion of the tissue; Analyzing the Raman spectrum from the reflection of the laser irradiated on the second portion of the tissue; Applying pressure to the tissue; Measuring the Hb concentration of the tissue by analyzing the extent to which the electromagnetic waves are absorbed in the first portion of the tissue after applying the pressure; Analyzing the Raman spectrum from the reflection of the laser irradiated to the second portion of the tissue after applying the pressure; Calculating an accurate Hb concentration from the Hb concentrations measured at the first site of the tissue before and after the pressure application; Measuring the blood glucose concentration of the tissue from the difference in the Raman spectra at the second site of the tissue before and after the pressure application; And calculating the final blood glucose level by correcting the measured blood glucose concentration according to the calculated Hb concentration.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings and the contents described in the accompanying drawings, but the present invention is not limited or limited to the embodiments. Like reference numerals in the drawings denote like elements.

3 is a diagram illustrating a non-invasive biometric measurement system 300 according to an embodiment of the present invention. Referring to FIG. 3, the non-invasive biometric measurement system 300 includes a tissue modulation unit 310, a Raman-Fluorecsence (RF) measuring unit 320, and a Hb (Hemoglobin) measuring unit 330. It includes.

The non-invasive biometric system 300 non-invasively measures blood glucose for a portion of the finger (hereinafter, tissue) in contact with a certain instrument.

The non-invasive biometric system 300 has the tissue modulation unit 310 to apply pressure to the tissue, the tissue modulation unit 310 includes a pressure applying unit 311 and a pressure sensor 312. do.

As illustrated in FIG. 4, the RF measuring unit 320 includes a laser diode (LD) 321, a light collecting unit 322, a light receiving unit 323, a spectrometer 324, a light sensing array 325, and a blood glucose analyzer ( 326). The R-F measuring unit 320 measures blood glucose concentration by analyzing Raman spectra from a reflection of a laser irradiated to a predetermined portion of the tissue before and after applying pressure to the tissue in the tissue modulation unit 310.

In particular, the non-invasive biometric measurement system 300 according to an embodiment of the present invention has the Hb measuring unit 330 for measuring the Hb concentration of the tissue, the Hb measuring unit 330 is a light source array ( 331, an optical sensor 332, and a concentration calculator 333. The Hb measuring unit 330 measures the Hb concentration of the tissue by analyzing the degree to which the predetermined electromagnetic waves are absorbed at a predetermined portion of the tissue before and after applying the pressure in the tissue modulation unit 310.

Accordingly, the RF measuring unit 320 corrects the blood glucose concentration measured from the analysis of Raman spectra before and after applying the pressure by the RF measuring unit 320 according to the Hb concentration measured by the Hb measuring unit 330. Calculate your final blood glucose level.

Hereinafter, the operation of the non-invasive biometric measurement system 300 will be described in more detail with reference to the flowchart of FIG. 5.

When the non-invasive biometric measurement system 300 is turned on, the tissue modulation unit 310, the R-F measurement unit 320, and the Hb measurement unit 330 operate as follows (S510).

First, before the tissue modulation unit 310 applies pressure to a predetermined portion of a finger as shown in FIG. 4, each of the RF measuring unit 320 and the Hb measuring unit 330 measures a Raman spectrum and an electromagnetic wave ( S520, S530).

In order to obtain a Raman spectrum of the laser reflected from a certain portion of the finger, the R-F measuring unit 320 generates a laser using the LD (321). The laser generated by the LD 321 is collected by the light collecting unit 322 and is incident on a predetermined portion of the finger through a hole in the finger contact mechanism. A predetermined optical system may be used to focus the laser onto the condenser 322. As such, the incident laser is scattered and reflected by blood components in the finger vessels. The reflected laser is collected at the light receiver 323 in the form of an optical system and transmitted to the spectrometer 324. The spectrometer 324 spectroscopy the laser collected by the light receiving unit 323 to generate a fluorescence spectrum. Accordingly, the light sensing array 325 detects and converts the fluorescence spectra that are spectrographed by the spectroscope 324 using predetermined sensing means into certain electrical signals. The blood glucose analyzer 326 calculates the intensity of the fluorescence spectra of the reflected laser and the Raman spectrum due to the glucose component in the blood vessel from the output of the light sensing array 325 (S520). The values calculated by the blood sugar analyzer 326 are stored in a predetermined memory before the tissue modulation unit 310 applies pressure.

Before measuring the pressure, the Hb measuring unit 330 generates a predetermined electromagnetic wave using the light source array 331 to measure the Hb concentration at another portion of the finger. The light source array 331 has at least two or more light sources with high or very low absorption in Hb, which generates electromagnetic waves. The light source array 331 generates electromagnetic waves having a wavelength of 1300 nm or less. Before the pressure is applied by the tissue modulation unit 310, electromagnetic waves having a large or very low absorption to Hb generated by the light source array 331 are sequentially transmitted through the finger and sensed by the photosensor 332. The optical sensor 332 may be installed in the finger contact mechanism as shown in FIG. The optical sensor 332 generates a predetermined electrical signal according to the intensity of the electromagnetic wave transmitted from the finger, and accordingly the concentration calculator 333 calculates a predetermined value representing the degree of absorption of the electromagnetic wave from the blood vessel (S530). . The values calculated by the concentration calculator 333 are stored in a predetermined memory before the tissue modulation unit 310 applies pressure.

On the other hand, after the measurement in step S520 and S530 as described above, the tissue modulation unit 310 applies pressure to a predetermined portion of the finger. The pressure sensor 312 of the tissue modulation unit 310 may be installed in the finger contact mechanism as shown in FIG. 4, and may be installed between the finger contact mechanism and a predetermined portion of the finger by a force pressed by the pressure applying unit 311. Sensing the pressure felt. The result detected by the pressure sensor 312 is fed back to the pressure applying unit 311, the pressure applying unit 311 applies a predetermined pressure while adjusting so that the detected result does not exceed the set value. The pressure set therein may be set differently according to various conditions, for example, hypotension / hypertension, obesity / normal, age, and the like.

After the tissue modulation unit 310 applies pressure to the finger, the RF measuring unit 320 and the Hb measuring unit 330 again measure the Raman spectrum and the electromagnetic wave by the methods of S520 and S530 (S540). , S550). Accordingly, first, the blood glucose analyzer 326 of the RF measuring unit 320 detects the fluorescence spectrum and the Raman from the reflection of the laser irradiated to a predetermined portion of the finger before and after the tissue modulation unit 310 applies pressure to the finger. Analyzing the spectra to calculate the blood sugar concentration (S560).

Before the pressure is applied to the finger, blood is filled in the blood vessel at the lower part touching the finger contact mechanism as shown in FIG. 6. In the blood, water, red blood cells, white blood cells, electrolytes, cholesterol, and the like are present in addition to glucose and Hb as shown in FIG. 7. Such blood components are pushed to another place where most of the pressure is not received when the pressure is applied as shown in FIG. 6, and the blood vessels of the finger region under pressure are empty without blood components.

As described above, when the tissue modulation part 310 analyzes the fluorescence spectra measured by the RF measuring part 320 before and after applying pressure to the finger, scatters with respect to molecules in blood. The intensities of the Raman spectra vary at certain wavelengths. In this method known as Raman-Fluorecsence (R-F) method, the fluorescence spectrum of the reflected laser is scattered with respect to the glucose component in blood vessels, and thus, the blood glucose level can be predicted by analyzing the Raman spectrum that appears at a specific wavelength as shown in FIG. 8.

According to this principle, the blood glucose analyzer 326 of the R-F measuring unit 320 calculates the blood glucose concentration from the intensity of the fluorescence spectra from the reflected laser and the intensity of the Raman spectrum by the glucose component in the blood vessel. The intensity of the fluorescence spectra and the Raman spectrum in the empty blood state after applying the pressure to the finger in the tissue modulation unit 310 may be used as reference data. That is, the difference between the intensity of the fluorescence spectra and the intensity of the Raman spectrum before and after applying the pressure to the finger in the tissue modulation unit 310 may be used to calculate the blood glucose concentration.

On the other hand, the concentration calculation unit 333 of the Hb measuring unit 330 is the electromagnetic modulating unit 310 before or after applying pressure to the finger, respectively, the electromagnetic wave having a large or very low absorption of Hb at a certain portion of the finger. Analyze the degree of absorption is measured to measure the Hb concentration of the finger (S570).

Since a large amount of blood is filled in the finger before pressure is applied to the finger, the degree of absorption of electromagnetic waves incident on the finger from the light source array 331 by the blood is greater than the degree of absorption after the pressure is applied to the finger. 9 is a graph for explaining the relationship between the wavelength and the Hb absorption coefficient. Hb absorption coefficients vary with wavelength. Before and after applying pressure to the finger in the tissue modulation unit 310, the Hb concentration of the finger may be calculated according to the difference in the degree of absorption of the electromagnetic waves of the light source array 331 from the blood, and before and after applying the pressure. Accurate concentration calculation is possible by analyzing the difference in Hb concentration.

As such, when the concentration calculating unit 333 of the Hb measuring unit 330 calculates the Hb concentration of the finger, the blood glucose analyzer 326 of the RF measuring unit 320 before the pressure is applied according to the Hb concentration. And later correcting the blood glucose concentration measured from the analysis of the Raman spectra to calculate the final blood glucose level (S580). Here, the blood glucose concentration may be differently corrected according to the Hb concentration. For example, as shown in FIG. 2, when a certain threshold (eg, the normal range of the Hb concentration) is set, and the Hb concentration calculated by the Hb measuring unit 330 is larger than the threshold, blood sugar according to the degree. The concentration can be corrected small in the threshold direction (A, B of FIG. 2). The present invention is not limited thereto, and the blood glucose concentration may be largely corrected in a direction opposite to the threshold if the result after the correction does not show a random characteristic according to the Hb concentration. Similarly, when the Hb concentration calculated by the Hb measuring unit 330 is smaller than the threshold value, if the result after correction does not show a random characteristic according to the Hb concentration, the blood glucose concentration may be corrected accordingly to a large or small size. (C, D of FIG. 2). In this way, when the pre-calculated blood sugar concentration is corrected by the Hb concentration, the influence of Hb is minimized so that an accurate blood sugar concentration can be calculated.

As described above, in the non-invasive biometric system 300 according to an embodiment of the present invention, the RF measurement unit 320 before and after applying the pressure to a predetermined portion of the finger using the tissue modulation unit 310 The blood glucose concentration measured from the spectrum is corrected according to the Hb concentration measured by the Hb measuring unit 330 to output the final blood glucose level.

The functions used in the methods and apparatus disclosed herein can be embodied as computer readable code on a computer readable recording medium. The computer-readable recording medium includes all kinds of recording devices in which data that can be read by a computer system is stored. Examples of computer-readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage, and the like, and may also be implemented in the form of a carrier wave (for example, transmission over the Internet). do. The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion.

As described above, although the present invention has been described with reference to limited embodiments and drawings, the present invention is not limited to the above embodiments, and those skilled in the art to which the present invention pertains various modifications and variations from such descriptions. This is possible. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined not only by the claims below but also by the equivalents of the claims.

As described above, the non-invasive biometric system and method according to the present invention eliminates the influence of other components in the blood, in particular Hb concentration on the blood glucose concentration measured by the RF method, thereby measuring blood glucose levels with increased accuracy. It has an effect.

Claims (17)

A tissue modulation unit for applying pressure to the tissue; A Hb (Hemoglobin) measurement unit for measuring the Hb concentration of the tissue by analyzing the degree of absorption of the predetermined electromagnetic waves in the first portion of the tissue before and after applying the pressure in the tissue modulation unit; And The tissue modulation part analyzes Raman spectra from the reflection of the laser irradiated to the second portion of the tissue before and after the pressure is applied to measure blood glucose concentration, and corrects the measured blood glucose concentration according to the measured Hb concentration. RF (Raman-Fluorecsence) measuring unit that calculates blood glucose Non-invasive biometric system comprising a. The method of claim 1, wherein the Hb measuring unit, A non-invasive biometric system, characterized in that to calculate the Hb concentration by analyzing the absorption of at least two wavelengths of electromagnetic waves before and after applying the pressure. The non-invasive biometric system according to claim 2, wherein the wavelength of the electromagnetic waves used before and after applying the pressure is 1300 nm or less. The method of claim 1, wherein the Hb measuring unit,  A light source array having at least two light sources for generating the electromagnetic waves; An optical sensor configured to sense electromagnetic waves after being incident from the at least two light sources and passing through the first portion of the tissue; And Concentration calculation unit for calculating the Hb concentration from the difference in absorption of the electromagnetic waves detected by the optical sensor before and after applying the pressure Non-invasive biometric system comprising a. The method of claim 4, wherein the optical sensor, And a device for contacting the tissue. The method of claim 1, wherein the R-F measuring unit, Non-invasive biometric system, characterized in that the final blood glucose level is generated by correcting the blood glucose concentration measured from the Raman spectrum according to the degree of the Hb concentration is greater or less than the threshold value. The method of claim 1, wherein the R-F measuring unit, A blood sugar analyzer for calculating the blood glucose concentration from the intensity of the fluorescence spectra calculated from the reflected laser and the intensity of the Raman spectrum by the glucose component in the blood vessel, and correcting the measured blood glucose concentration according to the measured Hb concentration Non-invasive biometric system comprising a. The method of claim 1, wherein the tissue modulation unit, And a predetermined pressure set between the device for contacting the tissue and a predetermined portion of the tissue. The method of claim 1, wherein the tissue modulation unit, A pressure sensor installed in a mechanism for contacting the tissue and sensing a pressure applied to a predetermined portion of the tissue; And Pressure applying unit for applying at least one pressure between the mechanism for contacting the tissue using a sensing result fed back from the pressure sensor and a predetermined portion of the tissue Non-invasive biometric system comprising a. The non-invasive biometric system of claim 1, wherein the tissue is a portion of a finger. Measuring the Hb concentration of the tissue by analyzing the degree of absorption of electromagnetic waves by the first portion of the tissue; Analyzing the Raman spectrum from the reflection of the laser irradiated on the second portion of the tissue; Applying pressure to the tissue; Measuring the Hb concentration of the tissue by analyzing the extent to which the electromagnetic waves are absorbed in the first portion of the tissue after applying the pressure; Analyzing the Raman spectrum from the reflection of the laser irradiated to the second portion of the tissue after applying the pressure; Calculating a final Hb concentration from the Hb concentrations measured at the first site of the tissue before and after the pressure application; Measuring the blood glucose concentration of the tissue from the difference in the Raman spectra at the second site of the tissue before and after the pressure application; And Calculating a final blood glucose level by correcting the measured blood glucose concentration according to the calculated final Hb concentration Non-invasive biometric method comprising a. The non-invasive biometric method according to claim 11, wherein at least two wavelengths of different electromagnetic waves are absorbed in Hb. The method of claim 12, wherein the wavelength of the electromagnetic waves is 1300 nm or less. The method of claim 11, And the final blood glucose level is generated by correcting the blood glucose concentration measured from the Raman spectrum according to the degree of the Hb concentration being greater or smaller than the threshold value. The method of claim 11, And the blood glucose concentration is calculated from the intensity of the fluorescence spectra calculated from the reflected laser and the intensity of the Raman spectrum by the glucose component in the blood vessel. The method of claim 11, Non-invasive biometric method, characterized in that to apply at least one pressure set between the device for contacting the tissue and a predetermined portion of the tissue. A computer-readable recording medium having recorded thereon a program for executing the method of any one of claims 11 to 15.

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