JP2011152321A - Spectrometry device, spectrometry method, and spectrometry program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a spectrometry device, a spectrometry method, and a spectrometry program, capable of improving measuring precision. <P>SOLUTION: Concentration of a measuring substance per unit optical path length, concentration of a substance more than the content of the measuring substance in a layer per unit optical path length, and a reflectance of an interface are taken for solutions. For every wavelength corresponding to the number of measuring substances, substances and interfaces, concentration of measuring substance per unit optical path length is computed by use of simultaneous equations including the product of the concentration per unit optical path length and molar extinction coefficient, and an equation that the reflectance at the interface and the total are equal to absorbance of the substance. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a spectroscopic measurement apparatus, a spectroscopic measurement method, and a spectroscopic measurement program, and is suitable for measuring, for example, hemoglobin concentration.

  2. Description of the Related Art Conventionally, there has been proposed an apparatus that noninvasively measures the concentration of a specific component of a living body by irradiating a test site with a predetermined band of light and performing spectroscopic analysis of the light reflected from the test site (for example, Patent Document 1).

  In this apparatus, the scattered light intensity of the wavelength absorbed by the biological component to be measured and the wavelength that is absorbed by the component that is not absorbed by the biological component that is the measurement target and has a larger component amount in the living body than the measurement target. The biological component concentration to be measured is obtained by the multiple regression analysis method for the scattered light intensities and the corresponding biological component concentrations.

JP 2009-273719 A

  However, the correlation between the reflectance of one wavelength absorbed by the measurement object and the reflectance of one wavelength non-absorbed by the measurement object does not reflect the absorption spectrum characteristic of the measurement object. The accuracy of measurement accuracy is poor compared to the case of reflecting.

  Moreover, although the light which injects into a biological body is scattered, the ratio is small compared with the ratio reflected at the interface in a biological body. Therefore, when the biological component concentration is determined using reflected light instead of transmitted light with respect to the living body, the reflectance of the interface that reflects in the living body is greatly involved in the measured value, but is ignored in the above document. Compared with the case of considering the measurement accuracy is poor.

  The present invention has been made in consideration of the above points, and intends to propose a spectroscopic measurement apparatus, a spectroscopic measurement method, and a spectroscopic measurement program capable of improving measurement accuracy.

In order to solve such a problem, the present invention is a spectroscopic measurement device, which has a transmittance of light transmitted through a layer between an interface where the light in the wavelength range irradiated by the irradiation means is regularly reflected in the human body and the surface of the human body. Measurement using the transmittance calculating means to calculate, the coefficient reading means for reading the molar extinction coefficient registered in the storage medium, the transmittance calculated by the transmittance calculating means, and the molar extinction coefficient read from the coefficient reading means Concentration calculating means for calculating the concentration per unit optical path length of the substance.
The concentration calculation means uses the concentration per unit optical path length of the measurement substance, the concentration per unit optical path length of the substance that is equal to or higher than the content of the measurement substance in the layer, and the reflectance of the interface, as a solution. In addition, for each wavelength corresponding to the number of interfaces, a simultaneous equation of an equation is generated in which the product of the concentration per unit optical path length and the molar absorption coefficient and the reflectance and sum at the interface are equal to the absorbance of the substance.

The present invention also relates to a spectroscopic measurement method, wherein the transmittance calculating means transmits the light transmitted through a layer between the interface where the light in the wavelength range irradiated by the irradiating means is regularly reflected in the human body and the surface of the human body. A transmittance calculating step for calculating the transmittance, a coefficient reading step for reading the molar absorption coefficient registered in the storage medium, and a transmittance calculated by the concentration calculating means in the transmittance calculating step and the molar absorbance read in the coefficient reading step. And a concentration calculating step for calculating a concentration per unit optical path length of the measurement substance using the coefficient.
In the concentration calculation step, the concentration per unit optical path length of the measurement substance, the concentration per unit optical path length of the substance that is about the content of the measurement substance in the layer, and the reflectance of the interface are used as a solution, and the measurement substance, substance In addition, for each wavelength corresponding to the number of interfaces, a simultaneous equation of an equation is generated in which the product of the concentration per unit optical path length and the molar absorption coefficient and the reflectance and sum at the interface are equal to the absorbance of the substance.

The present invention is also a spectroscopic measurement program, wherein the transmittance of light transmitted through a layer between an interface where light in a wavelength range irradiated by an irradiation unit is regularly reflected in a human body and a surface of the human body is transmitted to a computer. Calculating, reading the molar extinction coefficient registered in the storage medium, using the transmittance calculated by the transmittance calculating means and the molar extinction coefficient read from the coefficient reading means, per unit optical path length of the measurement substance Calculate the concentration.
The concentration per unit optical path length of the measured substance is the concentration per unit optical path length of the measured substance, the concentration per unit optical path length of the substance that is about the content of the measured substance in the layer, and the reflectance of the interface. For each wavelength corresponding to the number of substances to be measured, substances, and interfaces, a series of equations assuming that the product of the concentration per unit optical path length and the molar extinction coefficient and the reflectance and sum at the interface are equal to the absorbance of the substance. Calculated from the equation.

The simultaneous equations are not simply generated by using the concentration per unit optical path length of the measurement substance as a solution, but are generated by adding other elements to the measurement target.
Specifically, not only the concentration per unit optical path length of the measurement target, but also the content of the measurement substance in the layer between the interface where the light in the wavelength range irradiated by the irradiation means is regularly reflected in the human body and the human body surface The density per unit optical path length as described above is a calculation target. Further, the interface reflectance in the human body that is largely involved as light transmitted through the layer is also subject to calculation. A simultaneous equation is generated for each different wavelength obtained by discretely taking an absorption spectrum in correspondence with the number of calculation objects.
Therefore, the present invention can calculate the concentration per unit optical path length of the measurement substance in the layer in the human body more accurately than when the simultaneous equations are generated using the concentration per unit optical path length of the measurement substance as a solution. it can. Thus, the spectroscopic measurement apparatus, spectroscopic measurement method, and spectroscopic measurement program that can improve the measurement accuracy are realized.

It is the schematic which shows the structure of a spectrometer. It is the schematic where it uses for description of reflection in a human body epidermis. It is the schematic where it uses for description of spectroscopy by a prism. It is the schematic which shows the structure of a measurement part. It is the schematic which shows the functional structure of CPU in the light absorption coefficient calculation mode. It is a photograph which shows a color sample example. It is a graph with which it uses for description of transition of the calculation result in the extinction coefficient calculation mode. It is the schematic which shows the functional structure of CPU in density | concentration measurement mode. It is a graph with which it uses for description of transition of the calculation result in density | concentration measurement mode. It is the schematic which shows the example of a density | concentration display screen.

Hereinafter, modes for carrying out the invention will be described. The description will be in the following order.
<1. Embodiment>
[1-1. Configuration of Spectrometer]
[1-2. Configuration of measurement unit]
[1-3. Absorption coefficient calculation mode]
[1-4. Concentration measurement mode]
[1-5. Effect]
<2. Other embodiments>

<1. Embodiment>
[1-1. Configuration of Spectrometer]
FIG. 1 shows a spectroscopic measurement apparatus 1 according to the present embodiment. The spectroscopic measurement apparatus 1 includes an irradiation unit 10, a spectroscopic unit 20, a light receiving unit 30, and a measurement unit 40.

  The irradiation unit 10 irradiates light in a predetermined wavelength region so as to be incident on the irradiation surface IF from an oblique direction. In the case of this embodiment, the wavelength range is the visible light range.

  When a predetermined part of the human body is arranged on the irradiation surface IF, the visible light irradiated from the irradiation unit 10 is incident on the human body surface as shown in FIG. 2, and the base layer and the dermis layer of the epidermis (squamous epithelium) Specularly reflected at the interface, and passes through the human epidermis (between the basal layer and the human body surface) and exits from the human body surface.

  The spectroscopic unit 20 splits light coming from the irradiation surface IF into a plurality of wavelength components. For example, a prism can be applied to the spectroscopic unit 20. When a prism is applied, as shown in FIG. 3, the shorter the wavelength, the larger the angle (refractive index) at which the light bends at the interface between the optical medium and the prism. Is done.

  The light receiving unit 30 receives a plurality of wavelength components separated by the spectroscopic unit 20 and sends the light reception results to the measuring unit 40.

  The measuring unit 40 uses Lambert-Beer law. The Lambert-Beer law is that the absorbance is A, the concentration per unit optical path length [mol / L · cm] (hereinafter referred to as unit length concentration) is cl, and the molar extinction coefficient (hereinafter simply referred to as the extinction coefficient). Where ε is

  A = ε · cl (1)

Represented as:

  Absorbance A is expressed by the following equation, where transmittance is t.

  A = log (1 / t) (2)

Since it can be expressed by the common logarithm of the transmittance t as shown in FIG.

  log (1 / t) = ε · cl (3)

The relationship is established.

  The measurement unit 40 has a mode for calculating an extinction coefficient of a substance (hereinafter also referred to as an extinction coefficient calculation mode) and a mode for measuring the concentration of the substance (hereinafter also referred to as a concentration measurement mode).

  When the extinction coefficient calculation mode is executed, the measurement unit 40 calculates the extinction coefficient of the substance using the equation (3), and registers the extinction coefficient.

  On the other hand, when executing the concentration measurement mode, the measurement unit 40 calculates the concentration of the substance using the absorption coefficient calculated in the absorption coefficient calculation mode and the equation (3). And the measurement part 40 memorize | stores these density | concentrations and shows the transition of the said density | concentration as needed.

[1-2. Configuration of measurement unit]
As shown in FIG. 4, the measurement unit 30 is configured by connecting various hardware to a CPU (Central Processing Unit) 41 that controls the control.

  Specifically, a ROM (Read Only Memory) 42, a RAM (Random Access Memory) 43 serving as a work memory of the CPU 41, an operation input unit 44 for inputting a command according to a user operation, an interface unit 45, a display unit 46, and a storage The unit 47 is connected via the bus 48.

  The ROM 42 stores a program for executing an extinction coefficient calculation mode (hereinafter also referred to as a coefficient calculation program) and a program for executing a concentration measurement mode (hereinafter also referred to as a concentration measurement program). The The interface unit 45 is connected to the irradiation unit 10 and the light receiving unit 30 through a dedicated transmission path, and can be connected to other devices through a wired or wireless transmission path.

  A liquid crystal display, an EL (Electro Luminescence) display, or the like is applied to the display unit 46. For the storage unit 47, a magnetic disk represented by HD (Hard Disk), a semiconductor memory, an optical disk, or the like is applied. A removable memory (portable memory) such as a USB (Universal Serial Bus) memory or a CF (Compact Flash) memory may be applied.

  The CPU 41 expands, in the RAM 43, a program corresponding to a command given from the operation input unit 44 among the plurality of programs stored in the ROM 42, and the interface unit 45, the display unit 46, or the storage unit 47 is loaded according to the expanded program. Control appropriately.

[1-3. Absorption coefficient calculation mode]
When the CPU 41 expands the coefficient calculation program corresponding to the command for calculating the extinction coefficient from the operation input unit 44 in the RAM 43, as shown in FIG. 5, the substance determination unit 51, the drive control unit 52, the spectrum calculation unit 53, It functions as a unit length concentration difference acquisition unit 54 and an extinction coefficient calculation unit 55.

  The substance determining unit 51 determines a substance that is set in advance or designated as a measurement target from the operation input unit 44 as a substance whose extinction coefficient is to be calculated. In this embodiment, three types of hemoglobin (oxygenated hemoglobin, reduced hemoglobin, and glycated hemoglobin) are designated as measurement targets and melanin is set as a substance whose extinction coefficient is to be calculated.

  The drive control unit 52 sets irradiation conditions such as an irradiation light amount for the irradiation unit 10 and drives the irradiation unit 10 to irradiate irradiation light under the irradiation conditions. In addition, the drive control unit 52 sets a light receiving condition such as a sampling period for the light receiving unit 30 and drives the light receiving unit 30 to receive light with the light receiving condition. Visible light emitted from the irradiation unit 10 is reflected by a reference color sample, and the reflected light is split into a plurality of wavelength components by the spectroscopic unit 20 and reaches the light receiving unit 30.

  The spectrum calculation unit 53 includes a color sample (hereinafter also referred to as a target color sample) associated with a substance determined to calculate an extinction coefficient, and a color sample serving as a reference for the color sample (hereinafter also referred to as a reference color sample). ) In a predetermined order.

  For example, as shown in FIG. 6, the reference color sample and the target color sample are prepared as a comparison table of colors and identifiers such as substance names and numbers. The target color sample is a sample of a color that is exhibited when the unit length concentration of the substance whose extinction coefficient is to be calculated is different from the reference color sample.

  In the following, the target color sample corresponding to the unit length density difference between the oxygenated hemoglobin and the reference color sample is referred to as an OxyHb color sample, and the target corresponding to the unit length density difference between the reduced hemoglobin and the reference color sample. The color sample is called an Hb color sample. The target color sample corresponding to the unit length density difference between the glycated hemoglobin and the reference color sample is called an HbA1c color sample, and the target color sample corresponding to the unit length density difference between the melanin and the reference color sample is melanin. Called a color sample.

  Here, a specific method for acquiring a spectrum is given as an example. As a first stage, the spectrum calculation unit 53 determines a color sample to be acquired from among the reference color sample, the OxyHb color sample, the Hb color sample, the HbA1c color sample, and the melanin color sample.

  As a second step, the spectrum calculation unit 53 notifies the irradiation surface IF of the irradiation unit 10 that the color sample to be acquired should be arranged using, for example, the display unit 46 and the light reception result of the light receiving unit 30 Start getting.

  As a third stage, the spectrum calculation unit 53 calculates the ratio of the amount of received light to the amount of irradiation light (reflectance of the color sample) for each wavelength, and acquires the spectrum of the color sample determined as the acquisition target (FIG. 7A). ).

  In this way, the processes from the first stage to the third stage are performed until all the spectra in the reference color sample, the OxyHb color sample, the Hb color sample, the HbA1c color sample, and the melanin color sample are acquired. Incidentally, in FIG. 7, for convenience, a part of the melanin sample is omitted.

  The unit length concentration acquisition unit 54 is a unit length between the reference color sample in the color sample (OxyHb color sample, Hb color sample, HbA1c color sample, melanin color sample) associated with the substance determined by the substance determination unit 51. Get the density difference.

  The unit length density difference from the reference color sample corresponds to “cl” on the right side of the equation (3). As a specific method for obtaining the unit length density difference, for example, the unit length density difference between the reference color sample in the color sample associated with the substance determined by the substance determination unit 51 from the operation input unit 44 is calculated. There is a method to input.

  As another example, a server holding a substance and a unit length density difference control database is accessed, and a unit length density difference between a color sample associated with the substance determined by the substance determination unit 51 and a reference color sample is downloaded. There is a technique to do.

  In addition, the storage unit 47 stores a reference database of the substance and unit length concentration difference, and from the storage unit 47 to the reference color sample in the color sample associated with the substance determined by the substance determination unit 51. There is a method of reading the unit length density difference.

  However, the method for obtaining the unit length density difference from the reference color sample is not limited to these exemplified methods, and methods other than the exemplified methods can be widely adopted.

  The extinction coefficient calculation unit 55 acquires the spectra of all the color samples associated with the substance determined to calculate the extinction coefficient, and acquires the unit length density difference between the color sample and the reference color sample. In this case, the extinction coefficient is calculated using these.

  Here, a specific method for calculating the extinction coefficient is given as an example. As a first step, the extinction coefficient calculation unit 55 extracts the reflectance at a specific wavelength from the spectra of the reference color sample, the OxyHb color sample, the Hb color sample, the HbA1c color sample, and the melanin color sample (FIG. 7B )).

  In this embodiment, the specific wavelengths from which the reflectance is to be extracted are five wavelengths of 500 [nm], 540 [nm], 580 [nm], 620 [nm], and 660 [nm].

  These five wavelengths are included in a wavelength range in which the absorption spectrum of visible light reflected from the base layer of the human body and emitted from the human body surface through the human epidermis changes sharply compared to other wavelength ranges. Therefore, each of oxygenated hemoglobin, reduced hemoglobin, and glycated hemoglobin in capillaries existing in the basal layer of the human body is calculated as a non-overlapping specific value.

  As the second stage, the extinction coefficient calculation unit 55 calculates the logarithm of the reciprocal of each reflectance at the five wavelengths (FIG. 7C). The logarithm of the reciprocal of this reflectance corresponds to “log (1 / t)” on the left side of equation (3).

  As a third step, the extinction coefficient calculation unit 55 calculates the logarithm of the reciprocal of the reflectance for the five wavelengths in the reference color sample and the reflectance for the five wavelengths in the OxyHb color sample, the Hb color sample, the HbA1c color sample, and the melanin color sample. The difference between the reciprocal number and the logarithm is calculated (FIG. 7D).

  As a fourth step, the extinction coefficient calculation unit 55 calculates the difference and the unit length density difference between the reference color sample acquired by the unit length density acquisition unit 54 by substituting them into the equation (3). As a result, as shown in FIG. 7E, the extinction coefficients of oxygenated hemoglobin, reduced hemoglobin, glycated hemoglobin, and melanin determined by the substance determining unit 51 are calculated.

  When the extinction coefficient calculation unit 55 calculates the extinction coefficients of oxyhemoglobin, reduced hemoglobin, glycated hemoglobin, and melanin, the extinction coefficient is registered in the storage unit 47 and recorded.

[1-4. Concentration measurement mode]
On the other hand, when the CPU 41 develops in the RAM 43 a concentration measurement program corresponding to a command whose concentration should be measured from the operation input unit 44, as shown in FIG. 8, the drive control unit 52, the transmittance acquisition unit 61, and the absorption coefficient read Functions as a unit 62, an epidermis transmission characteristic analysis unit 63, a concentration calculation unit 64, and a graph presentation unit 65.

  As described above, the drive control unit 52 drives the irradiation unit 10 to irradiate irradiation light under a predetermined irradiation condition, and drives the light receiving unit 30 to receive light under a predetermined light reception condition.

  The transmittance acquisition unit 61 transmits light that is transmitted through the human body epidermis (between the basal layer and the human body surface) disposed on the irradiation surface IF of the irradiation unit 10 and is split into a plurality of wavelength components (see FIGS. 2 and 3). Among them, the transmittance for a specific wavelength is acquired.

  Here, a specific method for obtaining the transmittance is given as an example. As a first step, the transmittance acquisition unit 61 notifies that the living body part should be arranged with respect to the irradiation surface IF of the irradiation unit 10 using, for example, the display unit 46 and acquires the light reception result in the light receiving unit 30. Is started. In this embodiment, the living body portion to be disposed on the irradiation surface IF is the finger pad surface of the finger.

  As described above with reference to FIGS. 2 and 3, the light receiving unit 30 is incident on the surface of the human body, is regularly reflected at the interface between the basal layer and the dermis layer of the epidermis (squamous epithelium), and is emitted from the surface of the human body. The skin transmitted light is split into a plurality of wavelength components by the spectroscopic unit 20 and is incident thereon.

  As the second stage, the transmittance acquisition unit 61 calculates the ratio of the amount of received light to the amount of irradiation light (skin transmission light rate) for each wavelength, and acquires the spectrum of the skin transmission light (FIG. 9A).

  As a third step, the transmittance acquisition unit 61 has the same wavelength (500 [nm], 540 [nm], 580 [nm], 620) as the wavelength used in the extinction coefficient calculation mode in the spectrum of the epidermal transmitted light. [nm], 660 [nm]) is extracted (FIG. 9B).

  The extinction coefficient reading unit 62 reads out extinction coefficients of melanin, reduced hemoglobin, oxidized hemoglobin, and glycated hemoglobin registered in the extinction coefficient calculation mode from the storage unit 47 (FIGS. 9C to 9F).

  The skin transmission characteristic analysis unit 63 calculates the extinction coefficient in the extinction coefficient calculation mode using the epidermal transmission light rate acquired by the transmitted light rate calculation unit 61 and the extinction coefficient read by the extinction coefficient reading unit 62. The unit length concentration of the obtained substance and the reflectance at the interface between the basal layer and the dermis layer are calculated.

  In the human epidermis, melanin having a unit length concentration larger than the unit length concentration of the three types of hemoglobin specified as the measurement target is interposed. In the human epidermis, the visible light irradiated from the irradiation unit 10 is reflected before reaching the interface between the basal layer and the dermis layer. Specifically, as shown in FIG. 2, there are reflection on the surface of the human body and irregular reflection on the human body skin. For this reason, the epidermal transmitted light (the light that specularly reflects the interface between the basal layer and the dermis layer and passes through the human epidermis) is reflected at the interface between the basal layer and the dermis layer (hereinafter referred to as the human body interface) (Also called reflectance) is greatly involved.

  Therefore, in the epidermal transmission characteristic analysis unit 63, in addition to the unit length concentrations of the three types of hemoglobin designated as the measurement target, the unit length concentration of melanin larger than the unit length concentration of the hemoglobin, the basal layer and the dermis layer The reflectance at the interface is the calculation target.

  Specifically, the absorbance of the human epidermis is LogS, the unit length extinction coefficient of melanin is Mn, the unit length extinction coefficient of reduced hemoglobin is Hb, the unit length extinction coefficient of oxyhemoglobin is HbO2, and the unit length of glycated hemoglobin Assuming that the extinction coefficient is HbA1c and the human body interface reflectance is D, the equation (3) can be expressed by the following equation:

Mn · ε1 + Hb · ε2 + HbO2 · ε3 + HbA1c · ε4 + D
= -LogS (4)

It becomes.

  Therefore, the skin transmission characteristic analysis unit 63 calculates the skin transmission light rate acquired by the transmission light rate calculation unit 61 and the extinction coefficient read by the extinction coefficient reading unit 62 for each wavelength with respect to the equation (4). And a five-way simultaneous equation is generated as shown in FIG.

  The skin permeation characteristic analysis unit 63 solves the five-way simultaneous equations to obtain the unit length concentration of the substance for which the extinction coefficient is calculated in the extinction coefficient calculation mode and the reflectance at the interface between the base layer and the dermis layer. Is calculated.

  9G, the unit length extinction coefficient Mn of melanin is 1.47E-5 [mol / L · cm], and the unit length extinction coefficient Hb of reduced hemoglobin is 1.47E-5 [ mol / L · cm]. In addition, the unit length extinction coefficient HbO2 of oxyhemoglobin is 2.52E-5 [mol / L · cm], the unit length extinction coefficient HbA1c of glycated hemoglobin is 0.18E-5 [mol / L · cm], and reflection in the human body interface The rate D is 0.3.

  The concentration calculation unit 64 uses the unit length concentration of the substance calculated by the epidermis permeation characteristic analysis unit 63 to determine the substance (melanin, oxygenated hemoglobin, reduced hemoglobin, glycated hemoglobin) determined as a calculation target in the extinction coefficient calculation mode. Calculate the concentration.

  Specifically, the concentration of melanin is calculated using the unit length concentration of melanin and the average of the distance between the basal layer in the human body and the surface of the human body, for example.

  On the other hand, using the unit length concentrations of the three types of hemoglobin and the average of the distances between the basal layer and the human body surface in the human body, the hemoglobin concentration is calculated. Incidentally, in the human epidermis, capillaries including hemoglobin are in the vicinity of the basal layer, and the basal layer is approximately constant from the surface of the human body.

  When the concentrations of melanin, oxyhemoglobin, reduced hemoglobin, and glycated hemoglobin are calculated, the concentration calculation unit 64 stores these concentrations in the storage unit 47 in association with the date and time of the calculation.

  When the concentration is calculated by the concentration calculation unit 64 or when there is an instruction to present the concentration from the operation input unit 44, the graph presentation unit 65 associates the concentration stored in the storage unit 47 with the concentration. For example, the display screen shown in FIGS. 10 (A) to 10 (D) is displayed on the display unit 46.

  On this display screen, a graph (hereinafter referred to as a concentration transition graph) PGF with the vertical axis as the density at the center of the screen and the horizontal axis as the date and time (hereinafter referred to as a concentration transition graph) is displayed for each type. The upper and lower limits of the range to be shown are shown, and the concentration trend is plotted.

  A comment CM for the overall trend state in the concentration is attached immediately above the concentration transition graph PGF, and when the plot indicating the trend of the concentration is above or below the normal range, the plot position Is marked with a warning mark WM indicating that it is abnormal.

  In this way, the graph presentation unit 65 displays the concentration trend for a plurality of substances in the biological epidermis together with the corresponding normal range as the concentration transition graph PGF, and attaches the warning mark WM to the plot position outside the normal range, The overall trend status is attached as a comment CM.

  Therefore, the user can intuitively grasp the change, quality, measurement frequency, etc. of the substance concentration contained in his / her biological epidermis from the concentration transition graph PGF, the warning mark WM, and the comment CM.

[1-5. Effect]
In the above configuration, the measurement unit 40 solves the unit length concentration of the measurement substance, the unit length concentration of the substance that is about the content of the measurement target in the human epidermis, and the interface where the visible light is regularly reflected in the human body. Generate simultaneous equations as

  Specifically, the wavelength corresponding to the number to be solved using the spectrum of the user's epidermis transmitted light and the three types of hemoglobin and the molar extinction coefficient of melanin which is equal to or higher than the unit length concentration of those hemoglobins Every one meets Lambert-Beer's law (FIG. 9G).

  Rather than generating simultaneous equations by solving the unit length concentrations of the three types of hemoglobin specified as the measurement target, simultaneous equations are generated by adding other elements to the measurement target. Specifically, not only the unit length concentration of the measurement target, but also the unit length concentration of melanin that is higher than the content of the measurement target in the human epidermis and the interfacial interface reflectivity that is largely involved as light that passes through the human epidermis (Reflectance at the interface between the base layer and the dermis layer) is a calculation target.

  Therefore, the measurement part 40 can calculate the unit length density | concentration of the measuring object in a human body skin more correctly.

  By the way, it is known that the content of glycated hemoglobin is less in the blood than oxyhemoglobin or reduced hemoglobin. Specifically, it is about 4-5 [%] of hemoglobin.

  On the other hand, there is a wavelength region that changes sharply in the absorption spectrum of visible light compared to other wavelength regions. The absorption characteristics of glycated hemoglobin are involved in this wavelength range, and the number of wavelengths having a remarkable difference in extinction coefficient between glycated hemoglobin and other hemoglobins (oxygenated hemoglobin and reduced hemoglobin) is 580 [nm] or a number in the vicinity thereof. The inventors have confirmed that the wavelength is present.

  Therefore, even when other elements are added to the measurement target and a simultaneous equation is generated, the accuracy of the unit length concentration of glycated hemoglobin to be calculated increases as the distance from the wavelength reflected in the absorption spectrum based on 580 [nm] increases. Will be reduced.

  However, in this embodiment, the wavelengths to be noted (the wavelengths of the respective values to be adapted to the simultaneous equations) are selected before and after 580 [nm] as a reference. Therefore, the absorption characteristics of glycated hemoglobin having a small content in the human epidermis compared to oxyhemoglobin and reduced hemoglobin can be grasped more sensitively, and as a result, the unit length concentration can be accurately calculated.

  In addition, the measurement unit 40 determines the measurement substance to be used in the simultaneous equations and the content thereof from the reflectance of the color sample corresponding to the measurement material and the material to be measured in the human skin. Calculate the molar extinction coefficient of the substance.

  Therefore, the measurement unit 40 can easily increase the types of the measurement substance that can calculate the unit length concentration in the human epidermis and the substance that is about the content or more from the spectral result of the color sample.

  According to the above configuration, the spectroscopic measurement apparatus 1 that can improve the measurement accuracy can be realized by calculating the unit length concentration of the measurement target in the human epidermis from the simultaneous equations in which other elements are added to the measurement target. The

<2. Other embodiments>
In the above-described embodiment, three kinds of hemoglobin (oxygenated hemoglobin, reduced hemoglobin, and glycated hemoglobin) are designated as the measurement substances to be measured. However, the type of the measurement substance is not limited to hemoglobin. For example, various components in the human body such as collagen and bilirubin can be used as measurement substances.

  Incidentally, it is not an indispensable condition to use all three types of hemoglobin as measurement substances. For example, when only glycated hemoglobin is used as a measurement target, oxyhemoglobin, reduced hemoglobin, and melanin are set as substances that are about the content of the glycated hemoglobin in the human epidermis. As another example, when reduced hemoglobin and glycated hemoglobin are measured, oxyhemoglobin and melanin are set as substances that have a content of about or more than the content of the glycated hemoglobin in the human epidermis.

  In short, in the layer between the interface where the light in the wavelength range used for spectroscopy is regularly reflected in the human body and the surface of the human body, if a substance that is about the content of the substance specified as the measurement target is added, Various components in the human body can be used as measurement substances.

  In addition, the substance which becomes more than the content in the substance designated as the measurement target is set in advance in the above-described embodiment. However, depending on the type of measurement substance specified as the measurement target, the number, type, and all or part of the wavelength to be noticed should be determined. It may be.

  For example, the wavelength range used for spectroscopy, the layer of the interface and the surface of the human body where light in the wavelength range is regularly reflected in the human body, the content of the substance in the layer, and the absorption characteristics of the substance in the layer Is stored in the storage unit 47 as a database. In this way, depending on the type of measurement substance specified as the measurement target, the number and type of substances that are about the content of the measurement substance in the layer or more, and all or part of the wavelength to be noted are determined. can do. Therefore, as a result of reliably selecting a substance having a content level or more in the substance designated as the measurement target, it is possible to improve the measurement accuracy of the unit length concentration of the substance designated as the target.

  In the above-described embodiment, the wavelength range of the light irradiated by the irradiation unit 10 is the visible light range. However, the wavelength range of the light to be irradiated is not limited to the visible light range. Near-infrared light region (780 [nm] to 3 [μm]) may be applied.

  When the near-infrared light region is applied, the near-infrared light mainly passes through the human epidermis, is reflected at the interface between the dermis and the fat layer, and is emitted from the human body surface. Near-infrared light has the property of being particularly absorbed by hemoglobin contained in blood vessels intervening in the dermis. Therefore, the unit length concentration of hemoglobin can be acquired more accurately.

  In addition, the human body interface reflectance D in the equation (4) is the reflectance at the interface between the dermis and the fat layer as described above. In addition, since the dermis contains a large amount of collagen and contains receptors such as patchoni bodies and cell components of fat cells, it is also possible to calculate including the extinction coefficient and unit length concentration of the collagen or fat. .

  In the above-described embodiment, the concentration is calculated from the unit length concentration and the trend of the concentration is presented as necessary. However, it is not an essential condition to calculate the concentration. That is, the unit length density itself may be stored in the storage unit 47 and the trend of the unit length density may be presented.

  In the above-described embodiment, the spectroscopic measurement apparatus 1 that executes the extinction coefficient calculation mode and the concentration measurement mode is applied. However, a system that allows a spectroscopic measurement device that executes only the extinction coefficient calculation mode and a spectroscopic measurement device that executes only the concentration measurement mode to be connected via a wired or wireless communication medium such as a local area network or the Internet is applied. May be.

  The present invention can be used in the bio-industry such as genetic experiments, creation of medicines, or patient follow-up.

  DESCRIPTION OF SYMBOLS 1 ... Spectrometer, 10 ... Irradiation part, 20 ... Spectrometer part, 30 ... Light-receiving part, 40 ... Measuring part, 41 ... CPU, 42 ... ROM, 43 ... RAM, 44 ... Operation Input unit 45... Interface unit 46... Display unit 47... Storage unit 51 .sub.substance determining unit 52 .. drive control unit 53. , 55... Absorption coefficient calculation section, 61... Transmission acquisition section, 62... Absorption coefficient reading section, 63... Skin permeation characteristic analysis section, 64.

Claims (7)

A transmittance calculating means for calculating the transmittance of the light transmitted through the layer of the interface between the interface in which the light in the wavelength range irradiated by the irradiation means is regularly reflected in the human body and the human body surface;
Coefficient reading means for reading a molar extinction coefficient registered in the storage medium;
Concentration calculating means for calculating the concentration per unit optical path length of the measurement substance using the transmittance calculated by the transmittance calculating means and the molar extinction coefficient read from the coefficient reading means,
The concentration calculation means
Using the concentration per unit optical path length of the measurement substance, the concentration per unit optical path length of the substance that is about the content of the measurement substance in the layer, and the reflectance of the interface, the measurement substance, the substance, and For each wavelength corresponding to the number of interfaces, generate a simultaneous equation of the equation that the product of the concentration per unit optical path length and the molar extinction coefficient and the reflectance and sum at the interface are equal to the absorbance of the substance. measuring device. The spectroscopic measurement according to claim 1, wherein the measurement substance includes glycated hemoglobin, and the wavelength is selected by a number corresponding to the number of the measurement substance, the substance, and the interface based on 580 [nm]. apparatus. Calculates the reflectance of the reference color sample, which is the color to be used as a reference, and the contrast color sample, which is the color exhibited when the measured substance and the concentration per unit optical path length of the substance differ from the reference color sample. Reflectivity calculating means,
A density difference acquisition means for acquiring a density difference per unit optical path length between the reference color sample and the contrast color sample;
Using the difference between the reflectance of the reference color sample and the reflectance of the contrast color sample and the concentration difference acquired by the concentration difference acquisition means, the molar extinction coefficient of the measurement substance and the substance is calculated, The spectroscopic measurement apparatus according to claim 2, further comprising: coefficient registration means for registering in a storage medium. The spectroscopic measurement apparatus according to claim 2 or 3, wherein the substance includes melanin. The spectroscopic measurement device according to claim 2 or 3, further comprising a determining unit that designates the measurement substance and determines the number and type of the substances according to the type of the designated measurement substance. A transmittance calculating unit that calculates a transmittance of light that is transmitted through a layer between the interface in which the light in the wavelength range irradiated by the irradiation unit is regularly reflected in the human body and the surface of the human body;
A coefficient reading step for reading the molar extinction coefficient registered in the storage medium;
A concentration calculating step in which the concentration calculating means calculates the concentration per unit optical path length of the measurement substance using the transmittance calculated in the transmittance calculating step and the molar extinction coefficient read in the coefficient reading step; Have
In the concentration calculation step,
Using the concentration per unit optical path length of the measurement substance, the concentration per unit optical path length of the substance that is about the content of the measurement substance in the layer, and the reflectance of the interface, the measurement substance, the substance, and For each wavelength corresponding to the number of interfaces, a system of simultaneous equations is generated where the product of the concentration per unit optical path length and the molar extinction coefficient and the reflectance and sum at the interface are equal to the absorbance of the substance. Spectroscopic measurement method. Against the computer,
Calculating the transmittance of light that is transmitted through a layer between an interface where the light in the wavelength range irradiated by the irradiation means is regularly reflected in the human body and the surface of the human body;
Reading the molar extinction coefficient registered in the storage medium;
A spectroscopic measurement program for executing calculation of a concentration per unit optical path length of a measurement substance using the transmittance calculated by the transmittance calculating means and the molar extinction coefficient read from the coefficient reading means,
The concentration per unit optical path length of the above measured substance is
Using the concentration per unit optical path length of the measurement substance, the concentration per unit optical path length of the substance that is about the content of the measurement substance in the layer, and the reflectance of the interface, the measurement substance, the substance, and For each wavelength corresponding to the number of interfaces, the product of the concentration per unit optical path length and the molar extinction coefficient is calculated from the simultaneous equations of the equation where the reflectance and sum at the interface are equal to the absorbance of the substance. Spectroscopic measurement program.