JP7439456B2 - Biological information measuring device and biological information measuring method - Google Patents

Description

The present application relates to a biological information measuring device and a biological information measuring method.

In recent years, the number of diabetic patients has been increasing around the world, and a non-invasive blood sugar level measurement that does not involve blood sampling is desired. Various methods have been proposed for measuring biological information such as blood sugar levels using light, such as methods using near-infrared light, methods using mid-infrared light, and methods using Raman spectroscopy. Among these, the mid-infrared region is a fingerprint region where glucose absorption is large, and the sensitivity of measurement can be increased more than in the near-infrared region.

In addition, as a technology for measuring biological information, a calibration curve is obtained in advance to correct the influence of changes in the thickness of liquid etc. interposed between the biological body and the optical element, and this is used to calculate the measured values of biological information. An apparatus that performs conversion and correction has been disclosed (see, for example, Patent Document 1).

However, since the device of Patent Document 1 converts measured values using a calibration curve obtained in advance, if the measurement conditions change moment by moment due to the surrounding environment of the device or changes in the temperature of the living body, it may not be possible to accurately convert the biological information. There were cases where measurements could not be made.

An object of the present invention is to accurately measure biological information.

A biological information measuring device according to an aspect of the present invention includes a light source that emits a plurality of probe lights including a first probe light and a second probe light having a different wavelength from the first probe light; a light intensity detection unit that detects the light intensity of the probe light absorbed by the object; and an absorbance acquisition unit that obtains absorbance data of the probe light absorbed by the object based on the light intensity. a data holding unit that temporarily holds a plurality of first absorbance data of the first probe light and a plurality of second absorbance data of the second probe light acquired by the absorbance acquisition unit; and the data Based on information indicating the relationship between the first absorbance and the second absorbance, which is obtained using a plurality of data of the first absorbance and a plurality of data of the second absorbance, which are temporarily held by a holding unit . , an absorbance converter that converts the second absorbance into a converted absorbance that has corrected a deviation in absorbance ; and a biological information output unit that outputs biological information acquired based on the absorbance of the plurality of probe lights including the converted absorbance. , is provided.

According to the present invention, biological information can be accurately measured.

1 is a diagram showing an example of the overall configuration of a blood sugar level measuring device according to a first embodiment. FIG. 3 is a diagram showing the action of an ATR prism. FIG. 2 is a perspective view showing the structure of an ATR prism. FIG. 2 is a perspective view showing the structure of a hollow fiber. FIG. 2 is a block diagram of an example hardware configuration of a processing unit according to an embodiment. FIG. 2 is a block diagram showing an example of a functional configuration of a processing unit according to the first embodiment. It is a figure which shows the example of a switching operation of a probe light, (a) when using a 1st probe light, (b) when using a 2nd probe light, and (c) when using a 3rd probe light. It is. 3 is a timing chart showing an example of switching timing of probe light, in which (a) shows the state of the first shutter, (b) shows the state of the second shutter, (c) shows the state of the third shutter, and (d) shows the state of the photodetector. It is a figure which shows the output signal of. 3 is a flowchart showing an example of the operation of the blood sugar level measuring device according to the first embodiment. FIG. 4 is a diagram showing the probe light intensity changed in three or more steps, where (a) is the probe light intensity of a comparative example, and (b) is the probe light intensity changed in three or more steps. 3A and 3B are diagrams illustrating an example of correcting positional deviation of the probe light, in which (a) is a diagram showing the cross-sectional light intensity distribution of the probe light, (b) is a diagram showing the cross-sectional light intensity distribution of (a) after positional displacement, and (c) is a diagram showing a cross-sectional light intensity distribution of the probe light. ) is a diagram showing the cross-sectional light intensity distribution of the probe light including speckles, and (d) is a diagram showing the cross-sectional light intensity distribution of (c) after the position shift. FIG. 4 is a diagram showing the effect of the incident surface in an ATR prism, in which (a) shows the total reflection of the probe light when the incident surface is a flat surface, and (b) shows the total reflection of the probe light when the incident surface is a diffusing surface. A diagram showing reflection, (c) is the incident surface of the diffusing surface, (d) is the incident surface of the concave surface, and (e) is the incident surface of the convex surface. It is a figure which shows the relative positional shift of the 1st, 2nd hollow optical fiber and ATR prism, (a) is a case where ATR prism is not in contact with a living body, (b) is a figure where the first total reflection surface of ATR prism is attached to a living body. (c) is a case where a living body contacts the second total reflection surface of the ATR prism. It is a figure which shows the support member of 1st, 2nd hollow optical fiber, and ATR prism. FIG. 6 is a diagram illustrating an example of a method for visually recognizing a contact state between an ATR prism and lips. FIG. 2 is a diagram showing an example of the overall configuration of a blood sugar level measuring device according to a second embodiment. It is an enlarged view explaining the contact part of a piezoelectric drive part and a 1st hollow optical fiber. FIG. 6 is a diagram showing the action of the piezoelectric drive unit, in which (a) is a probe light image according to a comparative example, (b) is a cross-sectional light intensity distribution along AA in (a), and (c) is a probe according to a second embodiment. The optical image (d) is the BB cross-sectional light intensity distribution of (c). It is a diagram showing an example of the overall configuration of a blood sugar level measuring device according to a first modification. It is a figure which shows the example of a lens drive. FIG. 7 is a diagram showing an example of the overall configuration of a blood sugar level measuring device according to a second modification. FIG. 4 is a diagram showing an example of driving a mirror, in which (a) is vibrated by a piezoelectric drive unit, (b) is vibrated by a motor, and (c) is vibrated by a MEMS mirror. It is a figure which shows an example of the light source drive current based on a 3rd modification, (a) is a light source drive current of a comparative example, (b) is a high frequency modulated light source drive current. It is a figure which shows the ATR prism based on 3rd Embodiment, (a) When there is a measurement sensitivity area in both the 1st total reflection surface and the 2nd total reflection surface, (b) The center of the 2nd total reflection surface (c) A case where there is a measurement sensitivity region at only one location, and (c) a case where there is a measurement sensitivity region at a plurality of locations on the second total reflection surface. It is a figure which shows the example of a structure of the pressure detection part based on 4th Embodiment, (a) is a case where one pressure detection part is provided, (b) is a case where the pressure detection part is provided at both ends of an ATR prism, (c) is a case where a plurality of pressure detection sections are provided. FIG. 4 is a diagram illustrating the arrangement of the ATR prism on the lips of a living body in the fourth embodiment, (a) shows the state before the ATR prism comes into contact with the lips, and (b) shows the state where the living body holds the ATR prism in its mouth. FIG. 7 is a block diagram showing an example of a functional configuration of a processing unit according to a fourth embodiment. FIG. 6 is a diagram showing an example of the correspondence between the contact pressure between the ATR prism and the lips and the absorbance. FIG. 6 is a diagram showing an example of arrangement of pressure sensors on a support part, in which (a) shows a case where one pressure sensor is provided, (b) shows a case where pressure sensors are provided on both end sides of an ATR prism, and (c) shows a case where a pressure sensor is provided at both ends of the ATR prism. This is a case where a plurality of pressure sensors are provided. FIG. 3 is a diagram illustrating an example of the positional relationship in the thickness direction of a pressure sensor, a support portion, and an ATR prism. FIG. 7 is a diagram illustrating another example of the positional relationship in the thickness direction of the pressure sensor, the support part, and the ATR prism, in which (a) is the case where the pressure sensor is placed on the second total reflection surface side, and (b) is the case where the pressure sensor is placed on the second total reflection surface side; This is a case where pressure sensors are arranged on both sides of the surface side and the second total reflection surface side. FIG. 7 is a block diagram showing an example of a functional configuration of a processing unit according to a fifth embodiment. FIG. 3 is a diagram illustrating an example of a temperature detection result and an acquisition result of blood sugar level data before correction. It is a figure showing the correlation between sublingual body temperature and blood sugar level. FIG. 3 is a diagram illustrating an example of a temperature detection result and an acquisition result of corrected blood sugar level data. FIG. 7 is a block diagram showing an example of the functional configuration of a processing unit according to a sixth embodiment. It is a figure which shows the correlation of a reference|standard light absorbency, 2nd light absorbency, and 3rd light absorbency. It is a figure showing the absorbance in one absorbance measurement. FIG. 7 is a diagram showing the correlation between the reference absorbance, the second absorbance, and the third absorbance in one absorbance measurement.

Hereinafter, embodiments for carrying out the invention will be described with reference to the drawings. In each drawing, the same components are designated by the same reference numerals, and redundant explanations may be omitted.

<Explanation of terms in the embodiment>
(Mid-infrared region)
The mid-infrared region refers to a wavelength region of 2 to 14 μm, and is an example of a specific wavelength region.

(probe light)
Probe light refers to light used for absorbance measurement and biological information measurement. In the embodiment, this corresponds to light that is totally reflected by a total reflection member, attenuated by a living body, and then detected by a light intensity detection unit.

(ATR method)
The ATR (Attenuated Total Reflection) method is a method that refers to the attenuated total reflection or total reflection absorption (ATR) method. A method of obtaining the absorption spectrum of a measured object using evanescent waves.

(absorbance)
Absorbance is a dimensionless quantity that indicates how much light intensity decreases when light passes through an object. In the embodiment, the attenuation by living organisms of the field seeping out from the total reflection surface is measured as absorbance using the ATR (Attenuated Total Reflection) method.

(Blood glucose level)
Blood sugar level refers to the concentration of glucose contained in the blood.

(detected value)
In the embodiment, it refers to a value detected by a light intensity detection section.

Hereinafter, embodiments will be described using a blood sugar level measuring device (an example of a biological information measuring device) that measures a blood sugar level (an example of biological information) based on the absorbance measured using an ATR prism (an example of a total reflection member). explain.

(wave number)
The relationship between wavelength λ (μm) and wave number k (cm −1 ) is k=10000/λ.

[First embodiment]
First, the blood sugar level measuring device 100 according to the first embodiment will be explained.

In this embodiment, multiple probe lights with different wavelengths in the mid-infrared region are incident on a total reflection member provided in contact with a living body, and the absorbance of each of the multiple probe lights is measured based on the ATR method. do.

Further, the light intensity detection section is provided to be able to detect the light intensity of the probe light emitted from the total reflection member, and at least a non-incidence period in which all of the plurality of probe lights are not incident on the total reflection member is provided. , controls the incidence of the probe light on the total reflection member. Then, based on the detection value by the light intensity detection unit in a state where the probe light is incident on the total reflection member and the above detection value in a state where all of the plurality of probe lights are not incident on the total reflection member, the mid-infrared region is determined. Obtain light absorbance data. This reduces the influence of the surrounding environment of the device, temperature changes in the living body, etc. on measurement, and accurately measures absorbance.

<Example of overall configuration of blood sugar level measuring device 100>
FIG. 1 is a diagram showing an example of the overall configuration of a blood sugar level measuring device 100. As shown in FIG. 1, the blood sugar level measuring device 100 includes a measuring section 1 and a processing section 2.

The measurement unit 1 is an optical head for performing the ATR method, and outputs a detection signal of the probe light attenuated by the living body to the processing unit 2. The processing unit 2 is a processing device that calculates absorbance data based on this detection signal, and also calculates and outputs a blood sugar level based on the absorbance data.

The measurement unit 1 includes a first light source 111, a second light source 112, a third light source 113, a first shutter 121, a second shutter 122, and a third shutter 123. It also includes a first half mirror 131, a second half mirror 132, a coupling lens 14, a first hollow optical fiber 151, an ATR prism 16, a second hollow optical fiber 152, and a photodetector 17.

The processing section 2 includes an absorbance acquisition section 21 and a blood sugar level acquisition section 22. The absorbance measurement device 101 includes a measurement section 1 and an absorbance acquisition section 21, as shown surrounded by a broken line.

A first light source 111, a second light source 112, and a third light source 113 in the measurement section 1 are each electrically connected to the processing section 2, and emit laser light in the mid-infrared region according to a control signal from the processing section 2. It is a quantum cascade laser.

In the embodiment, the first light source 111 emits a laser beam with a wave number of 1050 cm-1 as the first probe light, the second light source 112 emits a laser beam with a wave number of 1070 cm-1 as the second probe light, and the third light source 113 emits a laser beam with a wave number of 1100 cm −1 as the third probe beam.

The laser beams with wave numbers of 1050 cm-1, 1070 cm-1, and 1100 cm-1 correspond to the wave numbers of the absorption peak of glucose, respectively, and by measuring the absorbance using these wave numbers, the glucose concentration can be measured based on the absorbance. It can be done with high precision.

Further, the first shutter 121 , the second shutter 122 , and the third shutter 123 are electromagnetic shutters that are electrically connected to the processing section 2 and are controlled to open and close according to control signals from the processing section 2 .

When the first shutter 121 is opened, the first probe light from the first light source 111 passes through the first shutter 121 and reaches the first half mirror 131 . On the other hand, when the first shutter 121 is closed, the first probe light is blocked by the first shutter 121 and does not reach the first half mirror 131.

Further, when the second shutter 122 is opened, the second probe light from the second light source 112 passes through the second shutter 122 and reaches the first half mirror 131. On the other hand, when the second shutter 122 is closed, the second probe light is blocked by the second shutter 122 and does not reach the first half mirror 131.

Similarly, when the third shutter 123 is opened, the third probe light from the third light source 113 passes through the third shutter 123 and reaches the second half mirror 132. On the other hand, when the third shutter 123 is closed, the third probe light is blocked by the third shutter 123 and does not reach the second half mirror 132.

The first half mirror 131 and the second half mirror 132 are optical elements that transmit part of the incident light and reflect the rest. Such an optical element can be constructed by providing a substrate that is transparent to incident light with an optical thin film that transmits part of the incident light and reflects the rest.

However, this is not limited to optical thin films, and may also be constructed by forming a diffraction structure on a substrate that is transparent to incident light and that transmits a portion of the incident light and reflects (diffraction) the rest. good. It is preferable to use a diffraction structure in that light absorption can be suppressed.

The first half mirror 131 transmits the first probe light that has passed through the first shutter 121 and reflects the second probe light that has passed through the second shutter 122 . Further, the second half mirror 132 transmits each of the first probe light and the second probe light, and reflects the third probe light that has passed through the third shutter 123.

It is preferable that the light intensity ratio of the transmitted light and the reflected light in each of the first half mirror 131 and the second half mirror 132 is approximately 1:1, but it depends on the intensity of the probe light emitted from each light source, etc. The above light intensity ratio can also be adjusted.

The first to third probe lights that have passed through the first half mirror 131 or the second half mirror 132 are guided into the first hollow optical fiber 151 via the coupling lens 14 and propagate inside the first hollow optical fiber 151. The light is guided into the ATR prism 16 via the entrance surface 161 of the ATR prism 16.

The ATR prism 16 is an optical prism that propagates the first to third probe lights incident from the incident surface 161 toward the exit surface 164 while totally reflecting them, and emits the lights from the exit surface 164. As shown in FIG. 1, the ATR prism 16 is arranged with the first total reflection surface 162 in contact with a living body S (an example of an object to be measured).

The first to third probe lights guided into the ATR prism 16 are repeatedly totally reflected by the first total reflection surface 162 and the second total reflection surface 163 opposite to the first total reflection surface 162, and are emitted. It is guided into the second hollow optical fiber 152 via the surface 164.

The first to third probe lights guided by the second hollow optical fiber 152 reach the photodetector 17 . The photodetector 17 is a detector capable of detecting light with a wavelength in the mid-infrared region, and photoelectrically converts the received first to third probe lights and processes an electric signal according to the light intensity as a detection signal. Output to section 2. The photodetector 17 includes an infrared PD (Photo Diode), an MCT (Mercury Cadmium Telluride) detection element, a bolometer, and the like. Here, the photodetector 17 is an example of a light intensity detection section. Note that hereinafter, when the first to third probe lights are not distinguished, they may be simply referred to as probe lights.

The processing unit 2 is constructed from an information processing device such as a PC (Personal Computer). The absorbance acquisition section 21 in the processing section 2 acquires absorbance data of each probe light based on the detection signal of the photodetector 17 and outputs it to the blood sugar level acquisition section 22 . The blood sugar level acquisition unit 22 acquires blood sugar level data (blood sugar level information) of the living body based on the absorbance data of each probe light.

In addition, in FIG. 1, in order to clearly show the configuration of the measuring section 1 and the components included in the absorbance measuring device 101, the measuring section 1 is surrounded by a solid line frame, and the absorbance measuring device 101 is surrounded by a broken line frame. However, these do not represent the housing. The ATR prism 16 is not housed in a housing, and at least one of the first total reflection surface 162 and the second total reflection surface 163 can be brought into contact with any part of the living body.

<Function and configuration of ATR prism 16 etc.>
Next, the operation of the ATR prism 16 will be explained with reference to FIG. As shown in FIG. 2, the ATR prism 16 of the measurement unit 1 is placed in contact with the living body S. Each of the probe lights incident on the ATR prism 16 undergoes attenuation corresponding to the infrared absorption spectrum of the living body S. The attenuated probe light is received by a photodetector 17, and the light intensity of each probe light is detected. The detection signal is input to the processing section 2, and the processing section 2 acquires and outputs absorbance data and blood sugar level data based on the detection signal.

Attenuated infrared total reflection (ATR) method is effective for performing spectroscopic detection in the mid-infrared region where the intensity of absorbed light of glucose can be obtained. In the infrared ATR method, infrared probe light is incident on an ATR prism 16 with a high refractive index, and a field "spot" that appears when total reflection occurs at the interface between the ATR prism 16 and the outside world (for example, a living body S) is used. It uses the ``dashi''. If measurement is performed with a living body S, which is an object to be measured, in contact with the ATR prism 16, the seeping field will be absorbed by the living body S.

If infrared light in a wide wavelength range of 2 to 12 μm is used as the probe light, light at a wavelength caused by the molecular vibration energy of the living body S will be absorbed, and light at the corresponding wavelength of the probe light transmitted through the ATR prism 16 will be absorbed. Appears as a dip. This method is particularly advantageous in infrared spectroscopy using probe light with weak power because it can obtain a large amount of energy in the detection light transmitted through the ATR prism 16.

When infrared light is used, the depth at which the light seeps from the ATR prism 16 to the living body S is only about several microns, and the light does not reach the capillaries that exist at a depth of about several hundred microns. However, it is known that components such as plasma in blood vessels exude into skin and mucous membrane cells as tissue fluid (interstitial fluid). Blood sugar levels can be measured by detecting glucose components present in the interstitial fluid.

It is thought that the concentration of glucose components in interstitial fluid increases as it gets closer to capillaries, so the ATR prism is always pressed against the ATR prism at a constant pressure during measurement. To be advantageous for such pressing, the embodiment employs a multi-reflection ATR prism with a trapezoidal cross section.

Here, FIG. 3 is a perspective view showing the structure of the ATR prism according to the embodiment. As shown in FIG. 3, the ATR prism 16 is a trapezoidal prism. As the number of multiple reflections within the ATR prism 16 increases, the detection sensitivity of glucose increases. Furthermore, since the contact area with the living body S can be increased, fluctuations in the detected value due to changes in the pressure pressing the ATR prism 16 can be suppressed to a small level. The length L of the bottom surface of the ATR prism 16 is, for example, 24 mm. The thickness t is set to be thin, such as 1.6 mm or 2.4 mm, so that multiple reflections occur.

Candidates for the material of the ATR prism 16 are those that are not toxic to the human body and exhibit high transmission characteristics at a wavelength of around 10 μm, which is the absorption band of glucose. As an example, a ZnS (zinc sulfide) prism with a refractive index of 2.2 can be used, which allows a large amount of light to seep out, allows detection to be carried out to a deeper part, and has a refractive index of 2.2. Unlike ZnSe (zinc selenide), which is commonly used as an infrared material, ZnS has been shown to be non-carcinogenic, and is also used as a non-toxic dye (Litopone) in dental materials.

In a typical ATR measuring device, since the ATR prism is fixed to a relatively large device, the parts of the living body to be measured are limited to the body surface such as the fingertips and forearm. However, since the skin in these areas is covered with a stratum corneum approximately 20 μm thick, the detected glucose concentration is low. Furthermore, the stratum corneum is affected by the state of sweat and sebum secretion, which limits the reproducibility of measurements. Therefore, the blood sugar level measuring device 100 uses a first hollow optical fiber 151 and a second hollow optical fiber 152 that can transmit probe light, which is infrared light, with low loss, and one end of each fiber is brought into contact with the ATR prism 16. use

The first hollow optical fiber 151 is optically connected to the entrance surface 161 of the ATR prism 16 by bringing one end into contact with the ATR prism 16, so that the light emitted from the first hollow optical fiber 151 is transmitted to the ATR prism 16. The light is made incident on an incident surface 161.

Further, the second hollow optical fiber 152 is optically connected to the output surface 164 of the ATR prism 16 by having one end abutted against the ATR prism 16, so that the output light from the output surface 164 of the ATR prism 16 is The light is guided into two hollow optical fibers 152.

By using the ATR prism 16, it becomes possible to measure earlobes where capillaries exist relatively close to the skin surface and are less affected by sweat and sebum, and oral mucosa where there is no keratin.

FIG. 4 is a perspective view showing an example of the structure of a hollow optical fiber used in the blood sugar level measuring device 100. Mid-infrared light, which has a relatively long wavelength and is used for glucose measurement, cannot be transmitted through a silica glass optical fiber because the light is absorbed by the glass. Until now, various types of optical fibers for infrared transmission using special materials have been developed, but the materials had problems such as toxicity, hygroscopicity, and chemical durability, making it difficult to use them in the medical field. .

On the other hand, in the first hollow optical fiber 151 and the second hollow optical fiber 152, a metal thin film 242 and a dielectric thin film 241 are arranged in this order on the inner surface of a tube 243 made of a harmless material such as glass or plastic. There is. The metal thin film 242 is made of a material with low toxicity such as silver, and is coated with a dielectric thin film 241 to provide chemical and mechanical durability. Furthermore, since the core 245 is made of air that does not absorb mid-infrared light, low-loss transmission of mid-infrared light is possible over a wide wavelength range.

<Configuration of processing unit 2>
Next, the configuration of the processing section 2 will be explained with reference to FIGS. 5 and 6.

FIG. 5 is a block diagram showing an example of the hardware configuration of the processing unit 2 according to the embodiment. As shown in FIG. 5, the processing unit 2 includes a CPU (Central Processing Unit) 501, a ROM (Read Only Memory) 502, a RAM (Random Access Memory) 503, an HD (Hard Disk) 504, and an HDD (Hard Disk). (disk drive) controller 505 and a display 506. Also, an external device connection I/F (Interface) 508, a network I/F 509, a data bus 510, a keyboard 511, a pointing device 512, a DVD-RW (Digital Versatile Disk Rewritable) drive 514, and a media I/F F516, a light source drive circuit 517, a shutter drive circuit 518, and a detection I/F 519.

Among these, the CPU 501 controls the operation of the entire processing section 2. The ROM 502 stores programs used to drive the CPU 501, such as IPL (Initial Program Loader). RAM 503 is used as a work area for CPU 501.

The HD 504 stores various data such as programs. The HDD controller 505 controls reading and writing of various data to the HD 504 under the control of the CPU 501. The display 506 displays various information such as a cursor, menu, window, characters, or images.

External device connection I/F 508 is an interface for connecting various external devices. The external device in this case is, for example, a USB (Universal Serial Bus) memory, a printer, or the like. The network I/F 509 is an interface for data communication using a communication network. The bus line 510 is an address bus, a data bus, etc. for electrically connecting each component such as the CPU 501 shown in FIG. 5.

Further, the keyboard 511 is a type of input means that includes a plurality of keys for inputting characters, numerical values, various instructions, and the like. The pointing device 512 is a type of input means for selecting and executing various instructions, selecting a processing target, moving a cursor, and the like. The DVD-RW drive 514 controls reading and writing of various data on a DVD-RW 513, which is an example of a removable recording medium. Note that it is not limited to DVD-RW, but may be DVD-R or the like. The media I/F 516 controls reading or writing (storage) of data to a recording medium 515 such as a flash memory.

The light source drive circuit 517 is electrically connected to each of the first light source 111, the second light source 112, and the third light source 113, and outputs a drive voltage for causing these to emit infrared light according to a control signal. It is an electrical circuit. The shutter drive circuit 518 is an electric circuit that is electrically connected to each of the first shutter 121, the second shutter 122, and the third shutter 123, and outputs a drive voltage to open and close them according to a control signal.

The detection I/F 519 is an electric circuit such as an A/D (Analog/Digital) conversion circuit that serves as an interface for acquiring the detection signal of the photodetector 17. Note that the detection I/F 519 also has a function as an interface for acquiring detection signals from not only the photodetector 17 but also various sensors such as a pressure sensor and a temperature sensor, which are not shown in FIG.

Next, FIG. 6 is a block diagram showing an example of the functional configuration of the processing section 2 according to the first embodiment. As shown in FIG. 6, the processing section 2 includes an absorbance acquisition section 21 and a blood sugar level acquisition section 22.

The absorbance acquisition section 21 also includes a light source drive section 211, a light source control section 212, a shutter drive section 213, a shutter control section 214, a data acquisition section 215, a data recording section 216, and an absorbance output section 217. .

Among these, the function of the light source drive unit 211 is performed by the light source drive circuit 517 etc., the function of the shutter drive unit 213 is performed by the shutter drive circuit 518 etc., the function of the data acquisition unit 215 is performed by the detection I/F 519 etc., and the function of the data recording unit 216 is performed by the detection I/F 519 etc. These functions are realized by the HD 504 and the like. Further, each function of the light source control section 212, shutter control section 214, and absorbance output section 217 is realized by the CPU 501 executing a predetermined program.

The light source drive unit 211 outputs a drive voltage based on a control signal input from the light source control unit 212, and causes each of the first light source 111, the second light source 112, and the third light source 113 to emit infrared light. The light source control unit 212 controls the emission timing and light intensity of infrared light using a control signal.

The shutter drive unit 213 outputs a drive voltage based on a control signal input from the shutter control unit 214, and drives each of the first shutter 121, second shutter 122, and third shutter 123 to open and close. The shutter control unit 214 controls the timing and period for opening the shutter using a control signal. Here, the shutter control section is an example of an incidence control section.

The data acquisition unit 215 outputs to the data recording unit 216 a detected value of light intensity obtained by sampling the detection signal continuously outputted by the photodetector 17 at a predetermined sampling period. The data recording section 216 records the detected values input from the data acquisition section 215.

The absorbance output unit 217 performs predetermined arithmetic processing based on the detected value read from the data recording unit 216 to acquire absorbance data, and outputs the acquired absorbance data to the blood sugar level acquisition unit 22.

However, the absorbance output unit 217 may output the acquired absorbance data to an external device such as a PC via the external device connection I/F 508, or to an external server etc. via the network I/F 509 and the network. Good too. Alternatively, the data may be output and displayed on the display 506 (see FIG. 5).

Further, the blood sugar level acquisition section 22 includes a biological information output section 221. The biological information output unit 221 performs predetermined arithmetic processing based on the absorbance data input from the absorbance acquisition unit 21 to acquire blood sugar level data, and outputs the acquired blood sugar level data to the display 506 or the like for display.

However, the biological information output unit 221 may output blood sugar level data to an external device such as a PC via the external device connection I/F 508, or may output blood sugar level data to an external server, etc. via the network I/F 509 and the network. You may. Furthermore, the biological information output unit 221 may be configured to output the reliability of blood sugar level measurement as well.

Since the technology disclosed in Japanese Patent Application Publication No. 2019-037752 and the like can be applied to the process for acquiring blood sugar level data from absorbance data, further detailed explanation will be omitted here.

<Example of operation of blood sugar level measuring device 100>
Next, the operation of the blood sugar level measuring device 100 will be explained with reference to FIGS. 7 to 9.

(Example of probe light switching operation)
FIG. 7 is a diagram for explaining an example of a probe light switching operation. (a) shows the state of the measurement unit 1 when the first probe light is used, (b) when the second probe light is used, and (c) when the third probe light is used. .

In this embodiment, since the incidence of probe light from each light source into the ATR prism 16 is controlled by opening and closing each shutter, the first light source 111, the second light source 112, and the third light source 113 are It constantly emits infrared light.

In FIG. 7(a), the first shutter 121 is opened in response to a control signal. The first probe light emitted by the first light source 111 passes through the first shutter 121, passes through each of the first half mirror 131 and the second half mirror 132, and passes through the coupling lens 14 to the first hollow light. The light is guided to fiber 151. After that, the light beam propagates through the first hollow optical fiber 151 and then enters the ATR prism 16.

On the other hand, since the second shutter 122 and the third shutter 123 are each closed, the second probe light and the third probe light do not enter the ATR prism 16. Therefore, in this state, the absorbance of the first probe light due to attenuation by the ATR prism 16 is measured.

In FIG. 7(b), the second shutter 122 is opened in response to the control signal. The second probe light emitted by the second light source 112 passes through the second shutter 122, is reflected by the first half mirror 131, passes through the second half mirror 132, and passes through the coupling lens 14 into the first hollow. The light is guided to an optical fiber 151. After that, the light beam propagates through the first hollow optical fiber 151 and then enters the ATR prism 16.

On the other hand, since the first shutter 121 and the third shutter 123 are each closed, the first probe light and the third probe light do not enter the ATR prism 16. Therefore, in this state, the absorbance of the second probe light due to attenuation by the ATR prism 16 is measured.

In FIG. 7(c), the third shutter 123 is opened in response to the control signal. The third probe light emitted by the third light source 113 passes through the third shutter 123, is reflected by the second half mirror 132, and is guided to the first hollow optical fiber 151 via the coupling lens 14. After that, the light beam propagates through the first hollow optical fiber 151 and then enters the ATR prism 16.

On the other hand, since the first shutter 121 and the second shutter 122 are each closed, the first probe light and the second probe light do not enter the ATR prism 16. Therefore, in this state, the absorbance of the third probe light due to attenuation by the ATR prism 16 is measured.

When all of the first shutter 121, second shutter 122, and third shutter 123 are closed, none of the first probe light, second probe light, and third probe light enters the ATR prism 16, and the light It no longer reaches the detector 17.

In this way, the shutter control unit 214 (see FIG. 6) serving as an entrance control unit controls the opening and closing of each shutter to maintain a state in which the first to third probe lights sequentially enter the ATR prism 16 and a state in which the first to third probe lights sequentially enter the ATR prism 16. - It is possible to switch the state in which all of the third probe light does not enter the ATR prism 16.

(Example of probe light switching timing)
Next, FIG. 8 is a timing chart for explaining an example of switching timing of the first to third probe lights. In FIG. 8, (a) shows the state of the first shutter 121, (b) shows the state of the second shutter 122, (c) shows the state of the third shutter 123, and (d) shows the output signal of the photodetector 17. ing. In each figure, when the signal level is 0, the shutter is closed, and when the signal level is 1, the shutter is opened. Furthermore, signals shown with diagonal hatching are related to the first probe light, signals shown with grid hatching are related to the second probe light, and signals shown without hatching are related to the third probe light. There is.

In FIG. 8A, the shutter control unit 214 opens the first shutter 121 and closes the second shutter 122 and third shutter 123. As shown in FIG. 8D, during a period 81 in which the first shutter 121 is open, the photodetector 17 outputs a detection signal when the first probe light is incident on the ATR prism 16.

Thereafter, at a timing when a predetermined period of time has elapsed, the shutter control unit 214 opens the second shutter 122 at the timing at which the first shutter 121 was closed (FIG. 8(b)). As shown in FIG. 8D, during a period 82 in which the second shutter 122 is open, the photodetector 17 outputs a detection signal when the second probe light is incident on the ATR prism 16.

Thereafter, at a timing when a predetermined period of time has elapsed, the shutter control unit 214 opens the third shutter 123 at the timing at which the second shutter 122 was closed (FIG. 8(c)). As shown in FIG. 8D, during a period 83 in which the third shutter 123 is open, the photodetector 17 outputs a detection signal when the third probe light is incident on the ATR prism 16.

Thereafter, when the shutter control unit 214 closes the third shutter 123 at a timing when a predetermined period of time has elapsed, the first shutter 121, the second shutter 122, and the third shutter 123 are all closed. The photodetector 17 outputs a detection signal in a state where all of the first to third probe lights are not incident on the ATR prism 16, as in the non-incident period 84 shown in FIG. 8(d).

Thereafter, at a timing when a predetermined period has elapsed, the shutter control unit 214 sequentially opens the first shutter 121, second shutter 122, and third shutter 123 for a predetermined time, and then closes them all. Then, such operations are repeated.

In this way, the shutter control unit 214 as an input control unit controls the first to third probe lights so that at least the non-incidence period 84 in which all of the first to third probe lights do not enter the ATR prism 16 is provided. The incidence on the ATR prism 16 can be controlled.

Here, a cycle 85 in FIG. 8(d) indicates one cycle of the control operation by the shutter control unit 214. As shown in FIG. 8(d), this one period includes a period in which the first to third probe lights enter the ATR prism 16 one by one, and a period in which all of the first to third probe lights enter the ATR prism 16. 16 includes a non-incidence period in which no incident occurs.

In each period within the period 85, the photodetector 17 outputs a detection signal of light intensity to the data recording section 216 via the data acquisition section 215. The data recording unit 216 includes a first detection value based on the detection signal of the first probe light, a second detection value based on the detection signal of the second probe light, a third detection value based on the detection signal of the third probe light, and a non-incident detection value. Each of the fourth detection values based on the detection signal of the period is recorded separately.

Here, the effect of the fourth detection value based on the detection signal during the non-incident period will be explained. The detection signal by the photodetector 17 includes the light intensity of the background light around the blood glucose level measuring device 100 as a bias signal, and in the mid-infrared region, the photodetector 17 also detects heat radiation (heat rays). Since it is detected as light intensity, the bias signal contains a large amount of the light intensity of this hot ray.

When the bias signal level changes due to a change in background light intensity, a change in temperature around the device, etc., the absorbance data acquired based on the detection signal of the photodetector 17 changes, causing a measurement error. In particular, the temperature changes from moment to moment due to the surrounding environment of the device, heat emitted by the living body, heat emitted by components such as the light source and photodetector, etc., and therefore changes the bias signal level and becomes a major factor in reducing measurement accuracy.

On the other hand, the detection signal of the photodetector 17 during the non-incident period 84 in FIG. 8 represents a bias signal that does not include the first to third probe light intensities. Therefore, in this embodiment, by subtracting the fourth detection value during the non-incident period 84 from the first to third detection values based on the first to third probe lights, the first to third detection values are calculated. The bias signal components included in each are removed. This makes it possible to obtain absorbance data with reduced effects of the environment around the device, temperature changes in the living body, etc., using the detected values of the first to third probe lights from which bias signal components have been removed.

Additionally, if the time difference becomes large between the probe light detection period and the non-incidence period, changes in the bias signal level due to temperature etc. due to the time difference will become large, and the influence of the bias signal may not be able to be corrected appropriately. . Therefore, in this embodiment, the influence of the bias signal is corrected using the detected value in the non-incident period immediately before the period in which the detected value of the probe light was acquired.

For example, in FIG. 8, the first detected value in the period 86 during which the first probe light is detected is corrected using the fourth detected value in the most recent non-incident period 84 instead of in the non-incident period 88 after the period 86. do. Further, the second detection value in the period 87 during which the second probe light is detected is corrected using the fourth detection value in the most recent non-incident period 84 or non-incident period 88. By doing so, the effects of changes in temperature and the like over time are more suitably reduced.

Here, the period 86 described above is an example of the first incidence period, and the period 87 is an example of the second incidence period. Furthermore, the period 86, the period 87, and the non-incident period 88 are periods included in one cycle. In this manner, the absorbance output unit 217 can output absorbance data corrected for the influence of the bias signal.

(Example of operation of blood sugar level measuring device 100)
FIG. 9 is a flowchart showing an example of the operation of the blood sugar level measuring device 100.

First, in step S91, in response to a control signal from the light source control unit 212, the first light source 111, the second light source 112, and the third light source 113 all emit infrared light. However, in this initial state, the first shutter 121, the second shutter 122, and the third shutter 123 are all closed.

Subsequently, in step S92, the shutter control unit 214 opens the first shutter 121 and closes the second shutter 122 and third shutter 123.

Subsequently, in step S93, the data recording unit 216 records the detection value (first detection value) by the photodetector 17 acquired by the data acquisition unit 215.

Subsequently, in step S94, the shutter control unit 214 opens the second shutter 122 and closes the first shutter 121 and the third shutter 123.

Subsequently, in step S95, the data recording unit 216 records the detection value (second detection value) by the photodetector 17 acquired by the data acquisition unit 215.

Subsequently, in step S96, the shutter control unit 214 opens the third shutter 123 and closes the first shutter 121 and the second shutter 122.

Subsequently, in step S97, the data recording unit 216 records the detection value (third detection value) by the photodetector 17 acquired by the data acquisition unit 215.

Subsequently, in step S98, the shutter control unit 214 closes the first shutter 121, the second shutter 122, and the third shutter 123.

Subsequently, in step S99, the data recording unit 216 records the detection value (fourth detection value) by the photodetector 17 acquired by the data acquisition unit 215.

Subsequently, in step S100, the absorbance output unit 217 corrects each of the first to third detection values read from the data recording unit 216 by subtracting the most recent fourth detection value for each period.

Subsequently, in step S101, the absorbance output unit 217 acquires absorbance data of the first to third probe lights based on the corrected first to third detection values, and outputs them to the biological information output unit 221.

Subsequently, in step S102, the biological information output unit 221 executes predetermined calculation processing based on the absorbance data of the first to third probe lights to obtain blood sugar level data, and displays the obtained blood sugar level data on the display 506 ( (see Figure 5) and display it.

In this way, the blood sugar level measuring device 100 can acquire and output blood sugar level data.

<Operations and effects according to the first embodiment>
The mid-infrared region is a fingerprint region where glucose absorption is large, and is more advantageous than the near-infrared region in terms of improving measurement sensitivity. However, since the mid-infrared region is a wavelength region that matches the radiation spectrum of an object at room temperature, the surrounding environment of the measurement device, the heat emitted by the living body, the heat emitted by the components of the light source and photodetector used in the measurement device, etc. As a result, the detection signal of the photodetector changes moment by moment. In particular, in the method of bringing a living body into contact with a total reflection member such as an ATR prism, the temperature of the total reflection member or the living body changes in a short time due to heat transfer from the living body, which may make it impossible to accurately measure absorbance.

Furthermore, when using light with a single wavelength or a narrow band of wavelengths near a single wavelength, the measurement accuracy of blood sugar levels may decrease (for example, Kasahara.R, Kino.S, Soyama.S, Matsuura. Y. “Noninvasive glucose monitoring using mid-infrared absorption spectroscopy based on a few wavenumbers”, Biomedical optics Express, 2018, 9(1), PP.289-302).

In this embodiment, first to third probe lights having different wavelengths in the mid-infrared region are incident on the ATR prism 16 provided in contact with the living body S, and the first to third probe lights are Measure the absorbance of each of the probe lights.

It also includes a photodetector 17 that is provided to be able to detect the light intensity of the first to third probe lights emitted from the ATR prism 16. The incidence of the first to third probe lights on the ATR prism 16 is controlled so that at least an incident period is provided. Then, the first to third detection values by the photodetector 17 in a state where each of the first to third probe lights is incident on the ATR prism 16, and the fourth detection value by the photodetector 17 during the non-incidence period. Based on this, absorbance data of light in the mid-infrared region is obtained.

This fourth detected value is based on a bias signal due to the environment surrounding the device, the heat of the living body S, etc., so by subtracting and correcting the fourth detected value from the first to third detected values, it is possible to It is possible to reduce the influence of changes in the temperature of the living body, etc. on measurements. Thereby, absorbance can be measured accurately.

Here, in the above correction process, any correction process can be executed based on the first to third detection values and the fourth detection value, but the fourth detection value is subtracted from the first to third detection values. By performing the process, the correction process can be executed more easily.

In this embodiment, the shutter control unit 214 as an input control unit controls the period in which the first to third probe lights are incident on the ATR prism 16 one by one, and the period in which all of the first to third probe lights are injected into the ATR prism 16. It is periodically controlled so that one cycle includes a non-incidence period in which the light does not enter the prism 16.

Thereby, the absorbance data corrected based on the first to third detection values and the fourth detection value can be repeatedly obtained, and the absorbance that changes over time can be accurately measured from time to time.

Furthermore, if the time difference becomes large between the period in which the first to third detected values were obtained and the non-incident period in which the fourth detected value was obtained, changes in temperature, etc. due to the time difference become large, and the influence of the bias signal becomes It may not be possible to correct it appropriately.

Therefore, in the present embodiment, the shutter control unit 214 as an incidence control unit controls the period 86 (first incidence period) during which the first probe light among the first to third probe lights enters the ATR prism 16, and It is periodically controlled so that one cycle includes a period 87 (second incidence period) in which the second probe light among the first to third probe lights is incident on the ATR prism 16 and a non-incidence period 88.

Then, the absorbance output unit 217 acquires first absorbance data based on the first detected value in the period 86 and the fourth detected value in the non-incident period 84 that is closest to the period 86, and also acquires the second detected value in the period 87. and the fourth detected value in the non-incident period 84 or the non-incident period 88 that is closest to the period 87, the second absorbance data is acquired. Here, the first absorbance data is an example of the first absorbance, and the second absorbance data is an example of the second absorbance.

Thereby, it is possible to obtain a detection value based on the bias signal most recent at the time when the detection value by the probe light is obtained, and the influence of temperature changes in the living body etc. can be minimized and the absorbance can be measured more accurately.

Note that in this embodiment, an example has been shown in which the first shutter 121, second shutter 122, and third shutter 123, which are electromagnetic shutters, are controlled to switch the incidence of the probe light onto the ATR prism 16; however, the present invention is not limited to this. It is not something that will be done. The incidence of the probe light into the ATR prism 16 may be switched by controlling the plurality of light sources to be switched on (emission) and off (non-emission). Alternatively, one light source that emits light of a plurality of wavelengths may be used, and the light source may be turned on and off for each wavelength.

Further, in this embodiment, an example is shown in which the first half mirror and the second half mirror are used as elements that transmit a part of the probe light and reflect the rest, but the invention is not limited to this, and the beam splitter Alternatively, a polarizing beam splitter or the like may be used.

Furthermore, a high refractive index material that transmits the probe light, such as germanium, has a high surface reflectance due to its material characteristics. For example, when light polarized perpendicularly to the plane of the substrate (s-polarized light) is incident on the substrate at an incident angle of 45 degrees, the ratio of transmission to reflection is approximately 1:1. Taking advantage of this fact, a germanium plate can be installed at an incident angle of 45 degrees and can be used in place of a half mirror. Note that since there is a 50% reflective component on the back side as well, a non-reflective anti-reflection film is applied to the back side.

<Various modifications of the first embodiment>
Here, since each component in this embodiment can be modified in various ways, various modifications will be described below.

(Timing of non-incident period)
First, in the above-described embodiment, an example is shown in which a period is provided in which the first to third probe lights are sequentially incident on the ATR prism 16 one by one, and a non-incidence period is provided at a subsequent timing.

On the other hand, a non-incidence period is provided after the period in which the first probe light is incident on the ATR prism 16, a non-incidence period is provided after the period in which the second probe light is incident on the ATR prism 16, and the third probe light is injected into the ATR prism 16. A non-incidence period may be provided after the period in which the light is incident on the prism 16. By doing so, it becomes easier to obtain a detection value based on the bias signal most recent at the time when the detection value by the probe light was obtained, and the influence of temperature changes in the living body etc. can be corrected with higher accuracy.

(Suppression of influence of linearity error of photodetector 17)
The photodetector 17 used in the blood sugar level measuring device 100 may include a linearity error, and the linearity error of the photodetector 17 causes a blood sugar level measurement error. Therefore, the influence of the linearity error can be reduced by changing the probe light intensity in three or more predetermined stages and comparing the probe light intensity with the value detected by the photodetector 17.

FIG. 10 is a diagram illustrating an example of the probe light intensity changed in three or more stages as described above, in which (a) is a diagram showing the probe light intensity according to a comparative example, and (b) is a diagram showing three or more stages. It is a figure which shows the probe light intensity changed to the above-mentioned stage. In FIG. 10, the hatched portion represents the first probe light intensity, the grating hatched portion represents the second probe light intensity, and the unhatched portion represents the third probe light intensity.

In FIG. 10(a), the intensity of each probe light is constant, whereas in FIG. 10(b), the intensity of each probe light gradually decreases stepwise in three or more stages. By changing the drive voltage or drive current of the light source into three or more predetermined steps (six steps in FIG. 10(b)), the intensity of the emitted probe light can be changed into three or more steps. . Note that the light intensity of the probe light in this case changes at a cycle shorter than the switching control cycle of the probe light by the shutter control unit 214 (for example, the cycle from steps S92 to S94 in FIG. 9). The switching control cycle of the probe light by the shutter control unit 214 corresponds to the “control cycle by the incidence control unit”.

If the photodetector 17 does not include a linearity error, the detected value by the photodetector 17 changes linearly with respect to changes in the probe light intensity. On the other hand, if the photodetector 17 includes a linearity error, the value detected by the photodetector 17 changes nonlinearly with respect to a change in the probe light intensity.

Therefore, the probe light is emitted while changing the light intensity in three or more stages, the detection value by the photodetector 17 at each stage is acquired, and the emitted probe light intensity data and the detection value by the photodetector 17 are obtained. The light intensity range in which linearity is ensured is determined by comparing the Then, of the probe light intensity that changes in three or more stages, only the portion where linearity is ensured is used to measure the absorbance and blood sugar level. Thereby, the absorbance and blood sugar level can be measured while reducing the influence of linearity errors of the photodetector 17.

The operation of identifying the light intensity range in which linearity is ensured may be performed prior to blood sugar level measurement, or may be performed in real time during blood sugar level measurement.

Furthermore, since there is only one photodetector 17 while there are multiple probe lights, the process of reducing the effect of linearity error of the photodetector 17 does not have to be performed using all of the multiple probe lights. This may be carried out using at least one of a plurality of probe lights.

(Detection of probe light by image sensor)
The photodetector 17 is not limited to one that uses one pixel (light receiving element), but may be a linear image sensor in which pixels are arranged in a line, or an area-shaped image sensor in which pixels are arranged two-dimensionally. An image sensor can also be used.

Here, since the detection signal of the photodetector 17 is an integral value of the received probe light intensity, when the living body S contacts the ATR prism 16 and the optical path of the incident light and the output light in the ATR prism 16 changes, The probe light intensity before and after the change is integrated, resulting in a detection error, which may make it impossible to obtain accurate absorbance data.

FIGS. 11A and 11B show such positional deviation of the probe light, and a region 171 is a region where the photodetector 17 receives the probe light. When the probe light shifts in the direction of the white arrow in FIG. 11(b), the probe light intensity distribution in the region 171 changes, and the detection signal by the photodetector 17 changes.

On the other hand, if an image sensor is used as the photodetector 17, the amount of positional deviation of the probe light can be determined from the probe light image captured by the image sensor, so the integral value of the light intensity distribution of the probe light after the positional deviation is used as the detection signal By doing so, the influence of positional deviation of the probe light can be corrected. An area 172 in FIG. 11(b) indicates an area where an integral value of the light intensity distribution is obtained using the probe light after the positional shift.

Further, when coherent light such as a laser beam is used as the probe light, a fine, patchy light intensity distribution called speckle may be superimposed on the probe light. FIG. 11C shows an example of the cross-sectional light intensity distribution of the probe light including speckles. Reference numeral 174 indicates a singular point of light intensity that may be included in the speckle image, and the singular point 174 is included in the region 173.

FIG. 11(d) shows a case where the probe light in FIG. 11(c) is displaced in the direction of the white arrow. In this state, the singular point 174 is no longer included in the region 173, and the change in the detection signal before and after the positional shift becomes significant. On the other hand, by using the integrated value of the light intensity distribution in the area 175 as a detection signal according to the amount of positional deviation of the probe light detected from the probe light image, the influence of the positional deviation of the probe light can be more appropriately reduced. It can be corrected.

In addition, the contact area between the living body S and the ATR prism 16 is estimated based on the probe light intensity distribution on the image sensor, and the sensitivity distribution within the plane of the ATR prism 16, which has been acquired and stored in advance before starting the measurement, is estimated. By correcting the detection value based on the detection signal of the image sensor, it is also possible to reduce measurement variation errors.

(Incidence surface to total reflection member)
In the embodiment described above, an example was shown in which the entrance surface 161 of the ATR prism 16 is a flat surface, but the invention is not limited to this. It's okay.

As shown in FIG. 12A, when the entrance surface 161 is a flat surface, the traveling direction of the probe light within the ATR prism 16 becomes uniform according to the angle of incidence on the entrance surface 161. Therefore, on the total reflection surface of the ATR prism 16 that the living body S comes into contact with, region dependence may occur in which the measurement sensitivity differs from region to region.

The detection signal of the photodetector 17 depends on the contact state, such as the size of the contact area of the living body S with the ATR prism 16. In particular, when the object to be measured is a living body S such as a lip or a finger, the reproducibility of the contact state tends to be low, so measurement variations may increase due to the region dependence of measurement sensitivity.

On the other hand, by making the incident surface 161 a diffusing surface and randomly changing the traveling direction of the probe light within the ATR prism 16, the area dependence of the measurement sensitivity can be reduced, as shown in FIG. 12(b). This can reduce measurement variations.

In addition to the diffusing surface shown in FIG. 12(c), the incident surface 161 can also be a concave surface shown in FIG. 12(d) or a convex surface shown in FIG. 12(e). The concave surface in FIG. 12(d) and the convex surface in FIG. 12(e) are examples of incidence surfaces having curvature. In this case as well, the optical path of the probe light can be made different as in the case of the diffusing surface, and the region dependence of measurement sensitivity can be alleviated, thereby reducing measurement variations.

Note that the same effect can be obtained by arranging a diffuser plate, lens, etc. on the optical path before the probe light enters the ATR prism 16, but in this case, the number of component parts of the device increases, making assembly difficult. Errors may lead to differences in measured values between devices (machine differences) and increased costs. It is more preferable to make the entrance surface 161 of the ATR prism 16 a diffusing surface or a curved surface because it can reduce such machine differences and increase costs.

(Light guiding part and total reflection member support part)
When the living body S contacts the ATR prism 16, if the relative positions of the first hollow optical fiber 151 and the second hollow optical fiber 152 and the ATR prism 16 shift, the incidence efficiency and output efficiency of the probe light to the ATR prism 16 will be reduced. may vary, increasing measurement dispersion.

FIG. 13 is a diagram illustrating the relative positional deviation between the first hollow optical fiber 151 and the second hollow optical fiber 152 and the ATR prism 16. (a) is when the ATR prism 16 is not in contact with the living body S, (b) is when the living body S is in contact with the first total reflection surface 162 of the ATR prism 16, and (c) is when the second total reflection surface of the ATR prism 16 is The cases in which the living body S comes into contact with the reflective surface 163 are shown.

As shown in FIG. 13(b), when the living body S contacts the first total reflection surface 162 of the ATR prism 16, a pressing force is applied downward as indicated by the white arrow, and the ATR prism 16 shifts downward. As a result, the ATR prism 16' becomes in the state shown, and the relative positions of the first hollow optical fiber 151 and the second hollow optical fiber 152 and the ATR prism 16' change.

Further, as shown in FIG. 13(c), when the living body S contacts the second total reflection surface 163 of the ATR prism 16, a pressing force is applied upward as indicated by the white arrow, and the ATR prism 16 is displaced upward. As a result, the ATR prism 16'' becomes in the state shown, and the relative positions of the first hollow optical fiber 151 and the second hollow optical fiber 152 and the ATR prism 16'' change.

Due to such relative positional deviation, the incidence efficiency and output efficiency of the probe light with respect to the ATR prism 16 fluctuate. In particular, when the object to be measured is a living body, it is not easy to keep the contact pressure constant, so measurement variations due to relative positional deviations are particularly likely to increase.

Therefore, in order to suppress relative positional deviation, it is preferable that the first hollow optical fiber 151, the second hollow optical fiber 152, and the ATR prism 16 be supported by the same support member.

FIG. 14 is a diagram illustrating an example of the configuration of a member that supports the first hollow optical fiber 151, the second hollow optical fiber 152, and the ATR prism 16. The light guiding support member 153 in FIG. 14 is a member that integrally supports the first hollow optical fiber 151 and the ATR prism 16. Further, the output support member 154 is a member that integrally supports the second hollow optical fiber 152 and the ATR prism 16.

By integrally supporting the first hollow optical fiber 151 and the ATR prism 16, even when the living body S comes into contact with the ATR prism 16, the two move together, so that no relative positional deviation occurs. Further, by integrally supporting the second hollow optical fiber 152 and the ATR prism 16, even when the living body S is brought into contact with the ATR prism 16, the two move together, so that no relative positional deviation occurs. Thereby, it is possible to suppress fluctuations in the incidence efficiency and output efficiency of the probe light due to contact of the living body S with the ATR prism 16, and it is possible to reduce measurement variations.

In addition, in the above-mentioned example, the light guide support member 153 and the output support member 154 are made into separate members, but the first hollow optical fiber 151, the second hollow optical fiber 152, and the ATR prism 16 are made into one member. It may be supported by a support member.

Furthermore, even in the case where the light guide section is configured with an optical element such as a mirror or a lens without using the first hollow optical fiber 151 as the light guide section, by integrally supporting the optical element and the ATR prism 16, Effects similar to those described above can be obtained.

Furthermore, by integrally supporting not only the light guide section but also the first light source 111, second light source 112, third light source 113, and photodetector 17 with the same support member, measurement variations can be reduced. It will be done.

(Detection and display of contact status)
When the ATR prism 16 is brought into contact with a living body part (lips, etc.) of a subject that is out of the field of view of the subject whose blood sugar level is to be measured, the state of contact between the living body part and the ATR prism 16 cannot be visually confirmed. Therefore, the contact state changes for each measurement, and measurement variations may increase.

On the other hand, as shown in FIG. 15, there is a camera 40 that photographs the contact area between the lip of the subject (living body S) and the ATR prism 16, and a display unit such as a liquid crystal display that displays the image photographed by the camera 40. 41 can also be added to the configuration of the blood sugar level measuring device 100.

By adjusting the contact state between the lips and the ATR prism 16 while viewing the image displayed on the display unit 41, the subject can improve the reproducibility of the contact state and reduce measurement variations.

[Second embodiment]
Next, a blood sugar level measuring device 100a according to a second embodiment will be explained.

In this embodiment, the first hollow optical fiber 151 (an example of a light guiding section) that guides the probe light to the ATR prism 16 is driven by a driving section. As a result, by time-averaging the detection signal of the probe light by the photodetector 17, absorbance caused by speckle of the probe light, output fluctuation of the light source, positional fluctuation of each component due to vibration of the blood glucose level measuring device, etc. Reduce measurement variation.

FIG. 16 is a diagram illustrating an example of the overall configuration of such a blood sugar level measuring device 100a. As shown in FIG. 16, the blood sugar level measuring device 100a includes a measuring section 1a and a processing section 2a. Furthermore, the measurement section 1a includes a piezoelectric drive section 181 (an example of a drive section) that drives the first hollow optical fiber 151, and the processing section 2a includes a drive control section 23 that controls the piezoelectric drive section 181. Here, the absorbance measurement device 101a is configured to include a measurement section 1a, a drive control section 23, and an absorbance acquisition section 21, as shown surrounded by a broken line.

The piezoelectric drive unit 181 includes a piezoelectric element that expands and contracts in a predetermined direction according to an input drive voltage. This piezoelectric drive unit 181 is arranged in contact with the intermediate portion in the length direction of the first hollow optical fiber 151 so as to expand and contract in a direction intersecting the propagation direction of the probe light by the first hollow optical fiber 151. . Here, the first hollow optical fiber 151 is an example of an "optical fiber", and the location where one end of the first hollow optical fiber 151 is attached to the ATR prism 16 is an example of a "predetermined location".

The drive control unit 23 is an electric circuit that outputs a drive signal to the piezoelectric drive unit 181 to drive the piezoelectric drive unit 181. The drive control section 23 outputs a drive voltage modulated at a predetermined cycle shorter than the detection cycle of the probe light intensity by the photodetector 17 to the piezoelectric drive section 181.

Here, FIG. 17 is an enlarged view for explaining the contact portion between the piezoelectric drive unit 181 and the first hollow optical fiber 151.

As shown in FIG. 17, the piezoelectric drive unit 181 expands and contracts in a direction (in the direction of the white arrow) that intersects the propagation direction of the probe light, and moves the position of the intermediate portion in the length direction of the first hollow optical fiber 151 (white). Change in the direction of the extraction arrow. More specifically, the piezoelectric drive unit 181 vibrates the intermediate portion in the length direction of the first hollow optical fiber 151 in the direction of the white arrow by repeating expansion and contraction according to the drive voltage input from the drive control unit 23. (driving) to periodically and finely change the position of the intermediate portion.

On the other hand, since one end of the first hollow optical fiber 151 is attached to the ATR prism 16, it does not move even if the intermediate portion in the longitudinal direction of the first hollow optical fiber 151 vibrates. Therefore, the piezoelectric drive unit 181 periodically finely changes the position of the intermediate portion in the length direction of the first hollow optical fiber 151 while maintaining the incident position and incident angle of the probe light incident on the ATR prism 16. be able to.

Note that as long as the position of the intermediate portion can be changed, the tip portion of the piezoelectric drive unit 181 and the intermediate portion may be connected by adhesive or the like, or they may not be connected and may be brought into contact with each other periodically to generate vibrations. It may be made possible.

Further, the frequency of vibration by the piezoelectric drive unit 181 is, for example, 130 Hz. However, the present invention is not limited to this, and it is sufficient to vibrate at a frequency sufficiently higher than the detection frequency of the probe light intensity by the photodetector 17, and it is preferable to determine an appropriate frequency according to the weight of the driven object. In the case of a lightweight object such as the first hollow optical fiber 151, the frequency can be as high as 100 kHz or more. Further, the detection frequency of the probe light intensity by the photodetector 17 is, for example, 2 to 3 Hz.

Further, the vibration amplitude caused by the piezoelectric drive unit 181 is preferably about 1/10 to about the same size as the beam diameter of the probe light. By vibrating the first hollow optical fiber 151 with this amplitude, the pattern of the probe light on the photodetector 17 changes, and the light intensity is integrated on the photodetector 17 to obtain a time-averaged effect. I can do it.

FIG. 18 is a diagram for explaining the action of such a piezoelectric drive section 181. (a) is a probe light image according to a comparative example, (b) is an AA cross-sectional light intensity distribution in (a), (c) is a probe light image according to this embodiment, (d) is B in (c) -B cross-sectional light intensity distributions are shown.

The probe light images in FIGS. 18(a) and 18(c) are images of the probe light emitted from the second hollow optical fiber 152 taken with an infrared camera, and the light intensity of the probe light detected by the photodetector 17 This is to explain the distribution.

In the probe light image shown in FIG. 18A, the piezoelectric drive unit 181 is not driven, and the first hollow optical fiber 151 is not vibrated. In this state, the probe light image has a noticeable mottled pattern due to speckles. The AA cross-sectional light intensity distribution in (a) shown in FIG. The intensity distribution variation width 177 is relatively large, ranging from 140 to 240 gradations.

On the other hand, in the probe light image according to the present embodiment shown in FIG. 18(c), the piezoelectric drive unit 181 is driven and the first hollow optical fiber 151 is vibrating. In this state, the probe light image varies minutely due to the vibration of the first hollow optical fiber 151 within the imaging period of the infrared camera, and a time-averaged probe light image is captured within the imaging period of the infrared camera. The light intensity distribution is smoothed by this time averaging effect, and the variation width 178 of the light intensity distribution within the detection area 176 shown in FIG. 18(d) is reduced to 180 to 230 gradations. Note that since the first hollow optical fiber 151 is vibrated while maintaining the incident position and angle of incidence of the probe light on the ATR prism 16, a time-averaged effect is obtained without changing the position of the probe light on the photodetector 17. be able to.

By reducing the width of variation in the light intensity distribution, variation in the values detected by the photodetector 17 is also reduced.

On the other hand, the detection value by the photodetector 17 may vary due to output variation of the light source that emits the probe light, and measurement variations may increase. Further, the position of each component of the blood glucose level measuring device changes due to vibration of the device, and the position of the probe light on the photodetector 17 changes, which may increase measurement variations. In these cases as well, variations in detected values can be reduced by the time averaging effect of the probe light due to the vibration of the first hollow optical fiber 151.

<Operations and effects according to the second embodiment>
As described above, in this embodiment, the first hollow optical fiber 151 that guides the probe light to the ATR prism 16 is driven by the piezoelectric drive unit 181. As a result, the detection signal from the photodetector 17 is time-averaged, thereby measuring the absorbance caused by speckles of the probe light, fluctuations in the output of the light source, fluctuations in the position of each component due to vibrations of the blood sugar level measuring device, etc. Variations can be reduced. Then, the absorbance can be accurately measured and the blood sugar level can be accurately measured.

If a probe light with low coherence is used, the variation in detected values due to speckles will be reduced, but even in this case, variations in the output of the light source, variations in the position of each component due to vibrations of the blood sugar level measuring device, etc. The effect of reducing measurement variations can be obtained.

In this embodiment, an example is shown in which the intermediate portion in the length direction of the first hollow optical fiber 151 is vibrated; however, the present invention is not limited to this, and the position of at least a portion of the first hollow optical fiber 151 is vibrated. may be changed. However, if the position of the intermediate portion is changed, the incident position and incident angle of the probe light to the ATR prism 16 can be maintained, so that the probe light intensity fluctuation due to the change in the incident position and incident angle of the probe light to the ATR prism 16 can be maintained. This is preferable because measurement errors caused by such factors can be suppressed.

Further, the direction changed by the piezoelectric drive unit 181 is not limited to the direction perpendicular to the propagation direction of the probe light by the first hollow optical fiber 151, and the position of at least a part of the first hollow optical fiber 151 is changed. It may be in any direction if possible. Further, the direction is not limited to one direction, and may be changed in a plurality of directions, or the direction of change may be changed two-dimensionally over time.

Further, in this embodiment, an example of a piezoelectric drive unit is shown as the drive unit, but the drive unit is not limited to this. As long as at least one of the position or angle of the light guiding section can be changed, an ultrasonic vibrator, a voice coil motor, or the like can be used as the driving section.

Note that effects other than the above are similar to those described in the first embodiment.

<Various modifications of the second embodiment>
Here, since each component in this embodiment can be modified in various ways, various modifications will be described below.

(First modification)
In this modification, a light guiding section that guides the probe light to the ATR prism 16 is configured to include a mirror (an example of a deflection section) and a lens (an example of a condensing section). Furthermore, the detection signal from the photodetector 17 is averaged over time by driving the lens included in the light guide section. This reduces measurement variations in absorbance caused by speckles of the probe light, fluctuations in the output of the light source, fluctuations in the position of each component due to vibrations of the blood sugar level measuring device, and the like.

FIG. 19 is a diagram illustrating an example of the overall configuration of a blood glucose level measuring device 100b according to this modification. As shown in FIG. 19, the blood sugar level measuring device 100b includes a measuring section 1b and a processing section 2b. The measurement unit 1b also includes a deflection mirror 191 that deflects the first to third probe lights toward the ATR prism 16, and a first condenser lens 192 and a second condenser lens 193 that condense the polarized light by the deflection mirror 191. and a piezoelectric drive unit 181b that drives the second condensing lens 193. Here, the configuration including the deflection mirror 191, the first condensing lens 192, and the second condensing lens 193 is an example of a light guide section. Further, it is preferable to use a material for the deflection mirror 191 made of gold or silver, which has a high reflectance for infrared light. It is preferable that the first condensing lens 192 and the second condensing lens 193 also have high condensing efficiency for light in the mid-infrared region.

Furthermore, the processing section 2b includes a drive control section 23b that controls the piezoelectric drive section 181b. The absorbance measurement device 101b includes a measurement section 1b, a drive control section 23b, and an absorbance acquisition section 21, as shown surrounded by a broken line.

The piezoelectric drive unit 181b includes a piezoelectric element that expands and contracts in a predetermined direction according to an input drive voltage. This piezoelectric drive unit 181b is arranged in contact with the side of the second condenser lens 193 so as to expand and contract in a direction intersecting the optical axis of the second condenser lens 193.

The drive control section 23b is an electric circuit that outputs a drive voltage for driving the piezoelectric drive section 181b to the piezoelectric drive section 181b. The drive control section 23b outputs a drive voltage modulated at a predetermined cycle shorter than the detection cycle of the probe light intensity by the photodetector 17 to the piezoelectric drive section 181b.

Here, FIG. 20 is an enlarged view for explaining an example of driving the second condensing lens 193. As shown in FIG. 20, the piezoelectric drive unit 181b expands and contracts in a direction intersecting the optical axis of the second condenser lens 193 (in the direction of the white arrow), and moves the position of the second condenser lens 193 in the direction of the white arrow. change. More specifically, the piezoelectric drive unit 181b vibrates (drives) the side part of the second condensing lens 193 in the direction of the white arrow by repeating expansion and contraction according to the drive voltage input from the drive control unit 23b. , the position of the second condensing lens 193 is periodically and minutely changed. As a result, the position of the probe light on the photodetector 17 changes periodically by periodically changing the incident position of the probe light on the ATR prism 16.

Note that as long as the position of the second condensing lens 193 can be changed, the tip portion of the piezoelectric drive unit 181b and the side portion of the second condensing lens 193 may be connected by adhesive or the like, or may not be connected. It may be brought into a state where it can be vibrated by periodically contacting it.

Further, the frequency of vibration caused by the piezoelectric drive unit 181b is, for example, 130 Hz. However, the present invention is not limited to this, and it is sufficient to vibrate at a frequency sufficiently higher than the detection frequency of the probe light intensity by the photodetector 17, and it is preferable to determine an appropriate frequency according to the weight of the driven object.

Since the second condensing lens 193 is heavier than the first hollow optical fiber 151 according to the second embodiment (see FIG. 16), it is preferable that the frequency be lower than the frequency at which the first hollow optical fiber 151 is vibrated.

Here, in the second embodiment described above, since the probe light is vibrated while maintaining the incident position and incident angle of the probe light to the ATR prism 16, even if the first hollow optical fiber 151 vibrates, the probe light on the photodetector 17 The position of the light did not change. However, in this modification, the position of incidence of the probe light on the ATR prism 16 changes due to the vibration of the second condensing lens 193, so the position of the probe light on the photodetector 17 changes with this change. .

In contrast, by setting the amplitude of the vibration caused by the piezoelectric drive unit 181b from 1/10 of the beam diameter of the probe light to about the same size as the beam diameter, even if the second condensing lens 193 vibrates, the photodetector 17 The probe light beams are partially overlapped at the top. Thereby, a time average effect can be obtained in the area where the probe lights on the photodetector 17 overlap.

The effects of the blood glucose level measuring device 100b according to this modification are the same as those described in the second embodiment, and therefore, redundant explanation will be omitted here.

In this modification, an example was shown in which the piezoelectric drive unit 181b contacts the side part of the second condenser lens 193 to vibrate the second condenser lens 193, but the piezoelectric drive unit 181b The second condensing lens 193 may be vibrated by contacting a holding part (not shown) that holds the lens 193.

Further, in this modification, an example of a piezoelectric drive unit is shown as the drive unit, but the invention is not limited to this. As long as at least one of the position or angle of the light guiding section can be changed, an ultrasonic vibrator, a voice coil motor, or the like can be used as the driving section.

(Second modification)
In the first modification, the second condensing lens 193 included in the light guide section was driven, but in this modification, the deflection mirror 191 included in the light guide section was driven to generate the probe light from the photodetector 17. The detection signal is time-averaged. This reduces measurement variations in absorbance caused by speckles of the probe light, fluctuations in the output of the light source, fluctuations in the position of each component due to vibrations of the blood sugar level measuring device, and the like.

FIG. 21 is a diagram illustrating an example of the overall configuration of a blood glucose level measuring device 100c according to this modification. As shown in FIG. 21, the blood sugar level measuring device 100c includes a measuring section 1c and a processing section 2c. The measurement unit 1c also includes a deflection mirror 191 that deflects the first to third probe lights toward the ATR prism 16, and a first condenser lens 192 and a second condenser lens 193 that condense the deflected light by the deflection mirror 191. , and a piezoelectric drive unit 1820 that drives the deflection mirror 191.

Furthermore, the processing section 2c includes a drive control section 23c that controls the piezoelectric drive section 181c. The absorbance measurement device 101c includes a measurement section 1c, a drive control section 23b, and an absorbance acquisition section 21, as shown surrounded by a broken line.

The piezoelectric drive unit 181c includes a piezoelectric element that expands and contracts in a predetermined direction according to an input drive voltage. The piezoelectric drive unit 181c is placed in contact with the back of the deflection mirror 191 so as to expand and contract in a direction perpendicular to the mirror surface of the deflection mirror 191.

The drive control section 23c is an electric circuit that outputs a drive voltage to the piezoelectric drive section 1820 to drive the piezoelectric drive section 1820. The drive control unit 23c outputs a drive voltage modulated at a predetermined cycle shorter than the detection cycle of the probe light intensity by the photodetector 17 to the piezoelectric drive unit 1820.

Here, FIG. 22 is a diagram illustrating an example of driving the deflection mirror 191. (a) shows the case where the piezoelectric drive unit 1820 is vibrated by the drive source, (b) shows the case where the motor 1821 is vibrated by the drive source, and (c) shows the case where the vibration is made by the MEMS (Micro Mechanical Electro System) mirror 1822. There is.

As shown in FIG. 22A, the piezoelectric drive unit 1820 expands and contracts in a direction perpendicular to the mirror surface of the deflection mirror 191 (in the direction of the outlined arrow), thereby changing the position of the deflection mirror 191 in the direction of the outlined arrow. The piezoelectric drive unit 1820 vibrates (drives) the deflection mirror 191 in the direction of the white arrow by repeating expansion and contraction according to the drive voltage input from the drive control unit 23c, and periodically changes the position of the deflection mirror 191 finely. let As a result, the incident position of the probe light on the ATR prism 16 changes, and the position of the probe light on the photodetector 17 changes periodically and finely.

Note that as long as the position of the second condensing lens 193 can be changed, the tip portion of the piezoelectric drive unit 181b and the side portion of the second condensing lens 193 may be connected by adhesive or the like, or may not be connected. It may be brought into a state where it can be vibrated by periodically contacting it.

Further, as shown in FIG. 22(b), the motor 1821 vibrates in a direction perpendicular to the mirror surface of the deflection mirror 191 (in the direction of the white arrow), and changes the position of the deflection mirror 191 in the direction of the white arrow. Here, the motor 1821 is a motor such as an annular (hollow) voice coil motor. The motor 1821 holds the deflection mirror 191 inside the ring and vibrates in the direction of the outline arrow in accordance with the drive voltage input from the drive control unit 23c, thereby vibrating the deflection mirror 191 in the direction of the outline arrow. The position of the deflection mirror 191 is periodically and minutely changed. As a result, the incident position of the probe light on the ATR prism 16 changes, and the position of the probe light on the photodetector 17 changes periodically and finely.

Further, as shown in FIG. 22(c), the MEMS mirror 1822 is a mirror in which a drive section such as a piezoelectric drive section is integrally formed by a semiconductor process. The piezoelectric drive unit deforms in accordance with the drive voltage input from the drive control unit 23c to rotate the deflection mirror 191 around an axis parallel to the mirror surface (for example, an axis perpendicular to the plane of the paper in FIG. 22), The angle of the deflection mirror 191 is changed. As a result, the deflection angle of the probe light by the deflection mirror 191 changes, the incident position of the probe light on the ATR prism 16 changes, and the position of the probe light on the photodetector 17 changes periodically and finely.

These driving frequencies, driving amplitudes, and effects are the same as those described in the first modification, so redundant explanations will be omitted here.

In this modification, examples of the drive unit include a piezoelectric drive unit, a voice coil motor, a MEMS mirror, etc., but the drive unit is not limited to these. As long as at least one of the position or angle of the light guiding section can be changed, an ultrasonic vibrator, an acousto-optic element, a polygon mirror, etc. may be used as the driving section.

(Third modification)
In the first and second modified examples, an example was shown in which the light guide section is driven to reduce measurement variations caused by speckles of the probe light. Since this speckle is generated by interference of scattered light of the probe light, etc., the generation of speckle can be suppressed by reducing the coherence of the probe light. Therefore, in this modification, by superimposing a high-frequency modulation component on the current that drives the light source, the coherency of the light source included in the blood glucose level measuring device is reduced, and the measurement variation in absorbance due to speckle of the probe light is reduced. Reduce.

FIG. 23 is a diagram illustrating an example of the light source drive current according to the present modification, in which (a) shows the light source drive current according to the comparative example, and (b) shows the high-frequency modulated light source drive current according to the present modification. It shows.

The light source control unit 212 (see FIG. 6) periodically outputs a pulsed drive current as shown in FIG. 23(a) to each of the first light source 111, the second light source 112, and the third light source 113. This causes them to emit pulsed probe light.

In this modification, a high frequency modulation component is superimposed on the pulsed drive current shown in FIG. The waveform of the high frequency modulation component may be sinusoidal or rectangular. Any modulation frequency from 1 MHz (megahertz) to several GHz (gigahertz) can be selected.

By superimposing high-frequency modulation components, the first light source 111, the second light source 112, and the third light source 113 can each emit pseudo-multimode laser light as probe light, and the coherence of the probe light increases. can be lowered. As a result, speckles of the probe light are reduced due to a decrease in coherence, and measurement variations due to speckles are reduced.

Although the second embodiment and the first to third modifications have been described above, it is also possible to realize an absorbance measuring device or a blood sugar level measuring device by combining some of them.

Further, in the example described above, an example was shown in which the present embodiment is applied to a blood sugar level measuring device, but the present invention is not limited to this. The embodiments can also be applied to a light guide device including a light guide section that guides probe light, a drive section that drives the light guide section, and a control section that controls the drive section. With such a light guiding device, it is possible to obtain the same effect as the absorbance measuring device described above.

[Third embodiment]
Next, a blood sugar level measuring device according to a third embodiment will be described.

In this embodiment, by limiting the measurement sensitivity region of the ATR prism 16, variations in absorbance measurement caused by variations in the contact area (contact area) between the ATR prism 16 and the living body S from measurement to measurement are reduced.

Here, the measurement sensitivity area refers to an area on the total reflection surface that has measurement sensitivity for measurement based on the ATR method. More specifically, it refers to a region in which a field attenuates by a living body due to the field seeping out from the total reflection surface.

FIG. 24 is a diagram illustrating a configuration example of the ATR prism 16d in which a measurement sensitivity region according to the present embodiment is defined. Each figure in FIGS. 24(a) to 24(c) shows three examples with different measurement sensitivity regions. In (a) to (c), the probe light P indicated by the dashed arrow enters the ATR prism 16d from the incident surface 161, is totally reflected four times by the first total reflection surface 162, and is totally reflected three times by the second total reflection surface 163. After total reflection, the light is emitted from the exit surface 164.

In each figure, a part of the first total reflection surface 162 is provided with a reflective film 162m made of gold or silver, which has a high reflectivity for infrared rays. Similarly, a part of the second total reflection surface 163 is also provided with a reflective film 163m made of a gold material or a silver material that has a high reflectivity for infrared rays. Such reflective films 162m and 163m can be formed by depositing gold or silver on the total reflection surface. Further, by using a mask during vapor deposition, gold or silver can be vapor-deposited in areas other than the masked area.

In the areas where the reflective films 162m and 163m are provided on the first total reflection surface 162 and the second total reflection surface 163, total reflection does not occur and the field does not seep out, so the field attenuation effect by the living body S cannot be obtained. It no longer falls under the measurement sensitivity area. In other words, each of the reflective films 162m and 163m has a function of defining a measurement sensitivity region on the total reflection surface. The reflective films 162m and 163m are examples of area defining parts. The areas where the reflective films 162m and 163m are provided on the first total reflection surface 162 and the second total reflection surface 163 are an example of "areas other than the measurement sensitivity area", and the reflective films 162m and 163m are not provided. The area is an example of "area other than the edge."

FIG. 24A shows a case where measurement sensitivity regions are provided on both the first total reflection surface 162 and the second total reflection surface 163. On either surface, reflective films 162m and 163m are provided in the area excluding the central portion. The central portion where the reflective films 162m and 163m are not provided corresponds to the measurement sensitivity region.

A field 162k indicated by diagonal hatching represents a field seeping out from the first total reflection surface 162. Because it is totally reflected twice, fields are generated in two places. Similarly, a field 163k represents a field seeping out from the second total reflection surface 163. Because it undergoes one total reflection, a field is generated at one location.

FIG. 24(b) shows a case where there is a measurement sensitivity region at one location in the center of the second total reflection surface 163. Since the first total reflection surface 162 is provided with a reflection film 162m over its entire surface, the first total reflection surface 162 does not have a measurement sensitivity region. A reflective film 163m is provided on the second total reflection surface 163 except for the central portion. A field 163k is generated in the central portion, and this portion becomes the measurement sensitivity region.

FIG. 24C shows a case where there are measurement sensitivity regions at a plurality of locations (here, three locations) on the second total reflection surface 163. Since the first total reflection surface 162 is provided with a reflection film 162m over its entire surface, the first total reflection surface 162 does not have a measurement sensitivity region. Reflective films 163m are provided on the second total reflection surface 163 except for three locations. A field 163k is generated at three locations where the reflective film 163m is not provided, and these locations become measurement sensitivity regions.

Here, in the blood sugar level measurement using the ATR prism, the subject uses the ATR prism so that the first total reflection surface 162 contacts the upper lip of the living body S, and the second total reflection surface 163 contacts the lower lip of the living body S. Measurements may be performed while holding the prism 16d in the user's mouth. In this case, since the central portion of the lips can easily apply a sucking force, the lips can be brought into relatively stable contact with the ATR prism. On the other hand, it is relatively difficult to apply a sucking force near both ends of the lips, and there are individual differences in the size of the mouth, so the contact area may vary and measurement variations may increase.

On the other hand, in the example of FIG. 24(a), the measurement sensitivity area near both ends of the ATR prism 16d that contacts both ends of the lips is defined by the reflective films 162m and 163m, and the contact area is an area where the contact area is likely to fluctuate. can be made so that it is not used in the measurement.

The regions where the reflective film 162m is provided in FIG. 24(a) correspond to both ends of the first total reflection surface 162. However, a configuration may be adopted in which a reflective film 162m is provided at either end. Further, the regions where the reflective film 163m is provided in FIG. 24(a) correspond to both ends of the second total reflection surface 163. However, a configuration may be adopted in which a reflective film 163m is provided at either end.

Furthermore, since the lower lip is easier to apply a gripping force to the ATR prism 16d than the upper lip, the variation in absorbance measurement may be reduced by using only the second total reflection surface 163 that the lower lip contacts. .

On the other hand, in the example of FIG. 24(b), the measurement sensitivity area is the entire surface of the first total reflection surface 162 that contacts the upper lip and the vicinity of both ends of the second total reflection surface 163 that contacts both ends of the lower lip. It is defined by the reflective films 162m and 163m that only the area in which the contact area is less likely to fluctuate is used for measurement.

Furthermore, the greater the number of total reflections on the total reflection surface, the greater the attenuation by the living body S, and the higher the measurement sensitivity. On the other hand, in the example of FIG. 24(c), regions where the reflective film 163m is not formed are provided at three locations where total reflection occurs on the second total reflection surface 163 with which the lower lip contacts. As a result, the blood sugar level can be measured with a greater number of total reflections (3 times) than the number of total reflections (1 time) in FIG. 24(b), and highly accurate measurement with higher measurement sensitivity is possible.

Note that the blood glucose level measuring device 100 according to the first embodiment can be applied to the overall configuration of the blood glucose level measuring device according to the present embodiment by replacing the ATR prism 16 with an ATR prism 16d.

Further, the regions where total reflection occurs on the first total reflection surface 162 and the second total reflection surface 163 can be specified by experiment or simulation based on the angle of incidence of the probe light on the ATR prism 16. Reflective films 162m and 163m can be provided in areas other than the specified areas where total reflection occurs.

<Operations and effects according to the third embodiment>
The generation area of the field seeping out from the total reflection surface of the ATR prism changes depending on the contact area (contact area) of the living body with the ATR prism. When measuring blood sugar levels, it is preferable that the contact area is constant, but in reality it is difficult to exactly match the contact area of the living body to the ATR prism for each measurement, so the contact area for each measurement is The measurement variation in absorbance may increase due to changes in the contact area. In particular, when using the lips as the measurement site, the contact area tends to change near the end of the lips depending on individual differences in lip size and the degree of force applied to hold the ATR prism, and measurement variations are likely to occur. .

In this embodiment, the measurement sensitivity region of the ATR prism 16d is defined by reflective films 162m and 163m as region defining portions. As a result, the contact area of the ATR prism 16d does not use the area where the contact area tends to fluctuate for measurement, and only the area where the contact area is relatively hard to fluctuate can be used for measurement. As a result, it is possible to reduce measurement variations in absorbance due to variations in the contact area between the ATR prism 16d and the living body S, and it is possible to reduce measurement variations in blood sugar levels.

[Fourth embodiment]
Next, a blood sugar level measuring device according to a fourth embodiment will be described.

In this embodiment, the contact pressure (pressure) of the living body S with respect to the ATR prism 16 is detected by a pressure sensor (an example of a pressure detection unit). By acquiring absorbance data of the probe light based on the light intensity of the probe light and the contact pressure detected by the pressure sensor, variations in absorbance measurement caused by fluctuations in contact pressure from measurement to measurement are reduced. Reduces blood sugar level measurement variations.

<Example of arrangement of pressure sensor 30>
FIG. 25 is a diagram illustrating an example of arrangement of the pressure sensor 30 on the ATR prism 16. Each of the figures in FIGS. 25(a) to 25(c) shows three examples in which the arrangement positions and numbers of pressure sensors 30 are different. 25(a) shows a case where one pressure sensor 30 is provided, FIG. 25(b) shows a case where a pressure sensor 30 is provided at both ends of the ATR prism 16, and FIG. 25(c) shows a case where a plurality of (three in this case) pressure sensors 30 are provided. This shows the case where .

As shown in each figure, the total reflection support part 31 supports the ATR prism 16 by contacting one side surface part of the ATR prism 16 (a surface other than the probe light incident surface and output surface), and also supports the ATR prism 16 for the first total reflection The pressure sensor 30 is placed on the surface 162 to support the pressure sensor 30.

The pressure sensor 30 is fixed by adhesive or the like in contact with at least one of the ATR prism 16 or the pressure sensor 30. The pressure sensor 30 is a sensor that detects the contact pressure Pr that the ATR prism 16 receives from the lips when the subject as the living body S holds the ATR prism 16 in the mouth. Various types of pressure sensors can be used as the pressure sensor 30, such as a capacitance type sensor, a strain gauge type sensor, a pressure sensitive resistance type sensor whose resistance value changes depending on pressure, and a pressure sensor using MEMS technology.

Although FIG. 25 shows an example in which the pressure sensor 30 is disposed only on the first total reflection surface 162 of the ATR prism 16, the pressure sensor 30 is It can be placed on at least one of the reflective surfaces 163.

If pressure sensors 30 are provided near both ends of the ATR prism 16 as shown in FIG. It is possible to detect pressure near both ends of the lips, where pressure tends to fluctuate. Moreover, if three pressure sensors 30 are provided as shown in FIG. 25(c), the distribution of contact pressure can be detected.

When the pressure sensor 30 is placed on the total reflection surface, the field does not seep out from the total reflection surface in the area where the pressure sensor 30 is placed, and the field attenuating effect by the living body S is no longer obtained. The area is no longer the measurement sensitivity area.

Therefore, the pressure sensor 30 can also have the function of the area defining section described in the third embodiment, and the pressure sensor 30 can be placed in an area where the contact area is likely to fluctuate, such as near both ends of the ATR prism 16. This makes it possible to reduce variations in absorbance measurement caused by variations in the contact area.

However, if the pressure sensor 30 is placed in all the areas where total reflection occurs in the ATR prism 16, measurement based on the ATR method will not be possible, so the pressure sensor 30 should not be placed in at least part of the area where total reflection occurs. It is preferable to ensure a measurement sensitivity range.

FIG. 26 is a diagram illustrating an example of the arrangement of the ATR prism 16 and the pressure sensor 30 on the lips, in which (a) shows the state before contact with the lips, and (b) shows the state in which a person holds the ATR prism 16 in their mouth. ing.

As can be seen from FIG. 26, the size of the ATR prism 16 is small compared to the lips of the subject as the living body S. Therefore, when the subject holds the ATR prism 16 in their mouth, their lips can come into contact with both the ATR prism 16 and the total reflection support section 31. Therefore, although FIG. 25 shows an example in which the pressure sensor 30 is placed across both the total reflection surface of the ATR prism 16 and the total reflection support part 31, the pressure sensor 30 is placed only on the total reflection support part 31. It may also be fixed.

<Functional configuration of processing unit 2d>
Next, the functional configuration of the processing section 2d included in the blood sugar level measuring device according to this embodiment will be explained. FIG. 27 is a block diagram illustrating an example of the functional configuration of the processing section 2d. As shown in FIG. 27, the processing section 2d includes an absorbance acquisition section 21d, and the absorbance acquisition section 21d includes a data acquisition section 215d, a notification section 218, and an absorbance output section 217d. Further, the absorbance output section 217d includes a pressure correction section 219.

Among these, the function of the data acquisition section 215d is realized by the detection I/F 519 (see FIG. 5), and the function of the notification section 218 is realized by the display 506 and the like. Further, the functions of the absorbance output section 217d and the pressure correction section 219 are realized by the CPU 501 executing a predetermined program.

The data acquisition unit 215d samples the detection signal continuously outputted by the photodetector 17 at a predetermined sampling period, and outputs the detected value of the light intensity acquired to the data recording unit 216. At the same time, contact pressure data obtained by sampling the detection signal continuously outputted by the pressure sensor 30 at a predetermined sampling period is output to the notification unit 218. However, the data acquisition section 215d may output the contact pressure data to the notification section 218 via the data recording section 216.

The notification unit 218 displays the contact pressure data on the display 506 so that the subject who holds the ATR prism 16 in his/her mouth can visually confirm the contact pressure data. The subject holding the ATR prism 16 in his/her mouth can adjust the contact pressure between the ATR prism 16 and his or her own lips while visually checking the contact pressure data displayed on the display 506.

However, the notification of contact pressure by the notification unit 218 is not limited to this. When the contact pressure data exceeds a predetermined contact pressure threshold, it is notified by emitting a beep or displaying a message on the display 506 to notify that the contact pressure has exceeded the threshold. Good too.

The absorbance output unit 217d performs predetermined calculation processing based on the detected value of the probe light intensity read from the data recording unit 216 to obtain absorbance data. Further, the pressure correction unit 219 in the absorbance output unit 217d corrects the absorbance data by referring to a table showing the correspondence between contact pressure and absorbance obtained in advance. The absorbance output section 217d outputs the corrected absorbance data to the blood sugar level acquisition section 22. This absorbance output section 217d is an example of "an absorbance output section that outputs the absorbance of the probe light obtained based on the light intensity of the probe light and the pressure."

The notification by the notification unit 218 and the correction of the absorbance data by the pressure correction unit 219 may be performed either alone or in combination.

FIG. 28 is a diagram showing an example of the correspondence between the contact pressure between the ATR prism 16 and the lips and the absorbance. The horizontal axis in FIG. 28 represents contact pressure, and the vertical axis represents absorbance. Further, this correspondence relationship is data obtained in advance through experiments. Note that the pressure sensor used in this experiment was of a pressure-sensitive resistance type.

A table corresponding to the data shown in FIG. 28 is stored in a storage device such as the HD 504 (see FIG. 5), and the pressure correction unit 219 corrects the absorbance data by referring to this table based on the contact pressure data. .

Furthermore, as shown in FIG. 28, since there is a linear relationship between the two, a linear equation corresponding to this linear relationship is stored in the HD 504, and the pressure correction unit 219 uses this linear equation based on the contact pressure data. The absorbance data may be corrected by referring to .

<Example of arrangement of pressure sensor on total reflection support part 31>
As described above, since the ATR prism 16 is smaller than the subject's lips, when the subject holds the ATR prism 16 in his or her mouth, the lips can come into contact with both the ATR prism 16 and the total reflection support section 31. . Therefore, the pressure sensor 30 is not placed across both the ATR prism 16 and the total reflection support part 31, but the pressure sensor 30 is placed only on the total reflection support part 31 to measure the contact pressure between the lips and the ATR prism 16. It can also be detected.

FIG. 29 is a diagram illustrating an example in which the pressure sensor 30 is arranged only on the total reflection support section 31. Each of the figures in FIGS. 29(a) to 29(c) shows three examples in which the arrangement positions and numbers of pressure sensors 30 are different. 29(a) shows a case in which one pressure sensor 30 is provided, FIG. 29(b) shows a case in which a pressure sensor 30 is provided at both ends of the ATR prism 16, and FIG. 29(c) shows a case in which a plurality of (three in this case) pressure sensors are provided. 30 is provided.

If pressure sensors 30 are provided at both ends of the ATR prism 16 as shown in FIG. It is possible to detect contact pressure near both ends of the lips, where pressure tends to fluctuate. Moreover, if three pressure sensors 30 are provided as shown in FIG. 29(c), the distribution of contact pressure can be detected.

Next, FIG. 30 is a diagram illustrating an example of the positional relationship in the thickness direction of the pressure sensor 30, the total reflection support part 31, and the ATR prism 16. FIG. 30 shows a state in which the pressure sensor 30 is placed on the total reflection support part 31 and one side of the ATR prism 16 is brought into contact with the total reflection support part 31 and fixed. The figure shows the view from the direction (along the direction).

In FIG. 30, t _atr represents the thickness of the ATR prism 16, t _sen represents the thickness of the pressure sensor 30, and t _sup represents the thickness of the total reflection support portion 31.

In this case, it is preferable to determine the thickness of each part so as to satisfy the following equation (1).

この関係を満たすことで、唇とＡＴＲプリズム１６の全反射面との接触を全反射支持部３１が阻害せず、唇とＡＴＲプリズム１６の全反射面を密着させることができる。

By satisfying this relationship, the total reflection support portion 31 does not interfere with the contact between the lips and the total reflection surface of the ATR prism 16, and the lips and the total reflection surface of the ATR prism 16 can be brought into close contact.

In addition, when the center line 16c of the ATR prism 16 in the thickness direction and the center line 21c of the total reflection support part 31 in the thickness direction are made to match, the thickness of each part is determined so that the following equation (2) is satisfied. Then, it is suitable.

この関係を満たすことで、圧力センサ３０のセンサ面をＡＴＲプリズム１６の第１全反射面１６２に対して、厚み方向にわずかに突出させることができ、唇のＡＴＲプリズム１６への接触圧を圧力センサ３０により好適に検出可能になる。

By satisfying this relationship, the sensor surface of the pressure sensor 30 can be made to slightly protrude in the thickness direction with respect to the first total reflection surface 162 of the ATR prism 16, and the contact pressure of the lips to the ATR prism 16 can be reduced to The sensor 30 enables suitable detection.

However, if the amount of protrusion is too large, the lips will not be able to properly contact the ATR prism 16, so it is more preferable to determine the thickness of each part so as to satisfy the following equation (3).

この関係を満たすことで、圧力センサ３０のセンサ面がＡＴＲプリズム１６の第１全反射面１６２に対して厚み方向に突出しすぎることを防ぎ、唇のＡＴＲプリズム１６への接触圧を圧力センサ３０によりさらに好適に検出可能になる。

By satisfying this relationship, the sensor surface of the pressure sensor 30 is prevented from protruding too much in the thickness direction with respect to the first total reflection surface 162 of the ATR prism 16, and the contact pressure of the lips to the ATR prism 16 is controlled by the pressure sensor 30. Detection becomes even more convenient.

FIG. 31 is a diagram illustrating another example of the positional relationship in the thickness direction of the pressure sensor 30, the total reflection support part 31, and the ATR prism 16. Similar to FIG. 30, FIG. 31 shows a state in which the pressure sensor 30 is placed on the total reflection support part 31 and one side of the ATR prism 16 is brought into contact with the total reflection support part 31 and fixed, and the pressure sensor 30 is shown in the side ( 3 shows a view seen from the longitudinal direction of the ATR prism 16.

31(a) shows a case where the pressure sensor 30 is arranged on the second total reflection surface 163 side, and FIG. A case where a pressure sensor 30 is arranged is shown.

In the arrangement shown in FIG. 31 as well, it is preferable to determine the thickness of each part so as to satisfy equations (1) to (3), as in the case described above.

<Operations and effects according to the fourth embodiment>
As explained above, in this embodiment, the contact pressure of the living body S with respect to the ATR prism 16 is detected by the pressure sensor 30, and based on the detected value of the probe light intensity by the photodetector 17 and this contact pressure, the probe Obtain light absorbance data.

More specifically, in this embodiment, the contact pressure data is displayed on the display 506 and reported so that the subject who holds the ATR prism 16 in his/her mouth can visually recognize it. Thereby, the subject holding the ATR prism 16 in their mouth can adjust the contact pressure between the ATR prism 16 and their own lips while visually checking the contact pressure data displayed on the display 506. As a result, it is possible to suppress variations in contact pressure from measurement to measurement, reduce measurement variations in absorbance due to variations in contact pressure, and reduce measurement variations in blood sugar levels.

Further, in this embodiment, the absorbance data is corrected with reference to data indicating the correspondence between contact pressure and absorbance acquired in advance, and the corrected absorbance data is output to the blood sugar level acquisition unit 22. Thereby, it is possible to suppress fluctuations in the contact pressure from measurement to measurement, reduce measurement variations in absorbance caused by the fluctuations, and reduce measurement variations in blood sugar levels.

Furthermore, by both reporting the contact pressure and correcting the absorbance data based on the contact pressure data, variations in absorbance measurement caused by fluctuations in contact pressure from measurement to measurement are reduced, and measurement variations in blood sugar levels are reduced. Can be reduced. By doing both, it is possible to shorten the time required for the subject to adjust the contact pressure, and to ensure correction accuracy by reducing the amount to be corrected.

Note that the pressure sensor 30 may be provided on at least one of the ATR prism 16 and the total reflection support section 31.

[Fifth embodiment]
Next, a blood sugar level measuring device according to a fifth embodiment will be described.

In this embodiment, by acquiring blood sugar level data based on the light intensity of the probe light and the temperature of at least one of the living body S or the ATR prism 16, the influence of the heat of the ATR prism 16 on the living body S and the living body To accurately measure the blood sugar level by suppressing the influence of the heat of S on the ATR prism 16.

<Functional configuration of processing unit 2e>
The functional configuration of the processing section 2e included in the blood glucose level measuring device according to this embodiment will be described with reference to FIG. 32. FIG. 32 is a block diagram illustrating an example of the functional configuration of the processing section 2e. As shown in FIG. 32, the processing section 2e includes an absorbance acquisition section 21e and a blood sugar level acquisition section 22e. The absorbance acquisition section 21e includes a data acquisition section 215e, and the blood sugar level acquisition section 22e includes a biological information output section 221e. Furthermore, the biological information output section 221e includes a temperature correction section 222.

Among these, the function of the data acquisition unit 215e is realized by the detection I/F 519 (see FIG. 5), etc., and the function of the biological information output unit 221e and the temperature correction unit 222 is realized by the CPU 501 executing a predetermined program, etc. This is realized by

The data acquisition unit 215e samples the detection signal continuously output by the photodetector 17 at a predetermined sampling period, and outputs the detected value of the light intensity to the data recording unit 216. At the same time, temperature data obtained by sampling the detection signal continuously outputted by the temperature sensor 50 at a predetermined sampling period is output to the data recording section 216. Here, the temperature sensor 50 is placed under the tongue of the subject corresponding to the living body S, and can output a detection signal of the sublingual body temperature to the data acquisition unit 215e. Furthermore, the temperature sensor 50 is an example of a temperature detection section.

The biological information output unit 221e performs predetermined calculation processing based on the absorbance data input from the absorbance output unit 217 to obtain blood sugar level data. Furthermore, the temperature correction unit 222 corrects the blood sugar level data based on the correspondence between the temperature and the blood sugar level that has been acquired in advance. This biological information output section 221e is an example of "a biological information output section that outputs biological information acquired based on the light intensity of the probe light and the temperature of at least one of the object to be measured and the total reflection member."

<Effect of temperature-based correction>
Here, the effect of correcting blood sugar level data based on temperature will be explained. First, the correlation between the temperature detected by the temperature sensor 50 (sublingual body temperature here) and the blood sugar level will be described.

In order to investigate this correlation, we conducted an experiment in which we measured the absorbance of subjects and detected their sublingual body temperature over a period of time from about 1 hour before the subject's meal to about 5 hours after the meal. Ta.

A normalized MLR (Multiple Linear Regression) model that performs normalization at a certain wave number was used as a model for acquiring (calculating) the blood sugar level based on the absorbance measurement results. Furthermore, 1000 cm-1 was used as the normalized wave number in the normalized MLR model. The calculation formula for the normalized MLR model is shown in equation (4) below.

（４）式において、ｙは、温度補正部２２２による補正を行っていない血糖値データ（補正前の血糖値データ）を表し、ｘ（ｋ）は波数ｋで測定された正規化前の吸光度データを表している。血糖値データは、吸光度データに基づいて上記の（４）式を用いて取得できる。

In equation (4), y represents blood sugar level data that has not been corrected by the temperature correction unit 222 (blood sugar level data before correction), and x(k) is absorbance data before normalization measured at wave number k. represents. Blood sugar level data can be obtained using the above equation (4) based on absorbance data.

FIG. 33 is a diagram illustrating an example of temperature detection results and blood sugar level data acquisition results. The horizontal axis in FIG. 33 indicates time, the first vertical axis (left axis) indicates the blood sugar level, and the second vertical axis (right axis) indicates the temperature detected by the temperature sensor 50. ing. The time of 0 (minutes) on the horizontal axis represents the time at which the subject ate, with the negative side representing before the meal and the positive side representing after the meal.

Further, the "○" mark in FIG. 33 indicates the acquired blood sugar level, and the small "•" mark indicates the detected sublingual body temperature. Note that the "○" mark in FIG. 33 is blood sugar level data before correction.

Blood sugar levels are generally considered to be low when fasting before a meal, and high after a meal; however, in FIG. 33, the blood sugar level is relatively high before a meal. On the other hand, sublingual body temperature before meals is low. Therefore, FIG. 33 suggests that there is a correlation between sublingual body temperature and blood sugar level.

FIG. 34 shows the results of investigating the correlation between sublingual body temperature and blood sugar level using the data in FIG. 33. The horizontal axis in FIG. 34 shows sublingual body temperature, and the vertical axis shows blood sugar level. Blood sugar level and sublingual body temperature should be unrelated, but as shown in FIG. 34, it can be seen that there is a negative correlation. The slope of the regression line in this negative correlation is -21 (mg/dl/deg). Therefore, by correcting the blood sugar level data acquired based on the absorbance data using the slope of this regression line, more accurate blood sugar level data can be acquired. A correction equation for blood sugar level data using the slope of the regression line is as shown in equation (5) below.

（５）式におけるｙ_ｃは補正後の血糖値データ、ｙは補正前の血糖値データ、Ｔは検出された舌下体温を表している。なお、切片の「－７６５」は、補正後の血糖値データが温度によらずほぼ同じ値になるように調整されている。

In equation (5), y_c represents the blood sugar level data after correction, y represents the blood sugar level data before correction, and T represents the detected sublingual body temperature. Note that the intercept "-765" is adjusted so that the corrected blood sugar level data will be approximately the same value regardless of temperature.

FIG. 35 is a diagram illustrating an example of the temperature detection result and the acquisition result of blood sugar level data when the blood sugar level data is corrected using equation (5). Since the view of FIG. 35 is the same as that of FIG. 33, redundant explanation will be omitted here.

Compared with FIG. 33 before correction, in FIG. 35, the blood sugar level data at the time before the meal is small, and the blood sugar level data is also small even after a long time has passed after the meal. Therefore, it can be seen that the blood sugar level data is corrected so as to follow the tendency for blood sugar levels to be lower when fasting before a meal or after a long period of time after a meal.

In addition, in this embodiment, an example of correction based on the correlation between the sublingual body temperature of the living body S and the blood sugar level data was shown, but the temperature of the ATR prism 16 is detected instead of the body temperature of the living body S, and the temperature of the ATR prism 16 is A similar effect was obtained even when correction was performed based on the correlation between temperature and blood sugar level data.

<Operations and effects according to the fifth embodiment>
When measuring the blood sugar level by bringing the ATR prism 16 into contact with the living body S, the acquired blood sugar level data may change depending on the temperature of the part of the living body S that the ATR prism 16 comes into contact with and the temperature of the ATR prism 16.

A possible reason for this is that the ATR prism 16 itself becomes warm due to the temperature of the part of the living body S that comes into contact with it, and the amount of mid-infrared light emitted by the ATR prism 16 itself changes, which affects the measurement. It is also conceivable that the temperature of the part of the living body S changes due to contact with the ATR prism 16, and the metabolism in the body and the emission of mid-infrared light from the part of the living body S change.

In the conventional technology, since the measurement is performed without bringing the optical measurement unit such as the ATR prism 16 into contact with the object to be measured, the temperature of the part of the living body S that the ATR prism 16 comes into contact with and the temperature of the ATR prism 16 may cause In some cases, blood sugar levels could not be measured accurately.

In this embodiment, blood sugar level data is acquired based on the light intensity of the probe light and the temperature of at least one of the living body S and the ATR prism 16. More specifically, blood sugar level data is acquired based on absorbance data acquired based on the light intensity of the probe light, and the blood sugar level data is corrected based on the temperature of the living body S detected by the temperature sensor 50.

To correct this blood sugar level data, a correction formula based on the correspondence between temperature and blood sugar level obtained in advance is used. Thereby, the influence that the heat of the ATR prism 16 has on the living body S and the influence that the heat of the living body S has on the ATR prism 16 can be suppressed, and the blood sugar level can be accurately measured.

In addition, although the present embodiment has shown an example in which the temperature sensor 50 detects the sublingual body temperature of the subject corresponding to the living body S, the present invention is not limited to this. The temperature sensor 50 may be placed on any part of the subject's body to detect the temperature of the part, or the temperature sensor 50 may be placed on the ATR prism 16 to detect the temperature of the ATR prism 16 or the temperature of the ATR prism 16. The temperature of the part of the subject that came into contact with the subject may be detected. However, it is preferable to obtain a correction formula based on the correspondence between temperature and blood sugar level in advance for each position of the temperature sensor 50, and use the correction formula corresponding to the position of the temperature sensor 50 during measurement.

When the temperature sensor 50 is placed on the ATR prism 16, placing it at the end of the total reflection surface where the living body S and the ATR prism 16 come into contact prevents the temperature sensor 50 from blocking the probe light and interfering with absorbance measurement. This is suitable because it can be done.

Furthermore, when using the body temperature data of the living body S, it is preferable to detect the temperature of the part of the living body S that contacts the ATR prism 16 because the blood sugar level data can be corrected more accurately. For example, when measuring by bringing the ATR prism 16 into contact with the lips, it is preferable to arrange the temperature sensor 50 to detect the temperature of the lips. However, it is also possible to measure the blood sugar level by bringing the ATR prism 16 into contact with various parts other than the lips, such as the earlobe and fingers.

Further, in this embodiment, an example is shown in which correction is performed using a correction formula based on the correspondence between temperature and blood sugar level, but the present invention is not limited to this. A table showing the correspondence between temperature and blood sugar level is created in advance and stored in a storage device such as the HD504, and corrected blood sugar level data is obtained by referring to this table based on the temperature detected at the time of measurement. You may also do so.

Further, although the present embodiment has shown an example using a linear correction equation, correction may be performed using a nonlinear polynomial as the correction equation. By using a nonlinear polynomial, more detailed correction becomes possible.

[Sixth embodiment]
Next, a blood sugar level measuring device according to a sixth embodiment will be described.

In this embodiment, among a plurality of probe lights including a first probe light and a second probe light having a different wavelength from the first probe light, the first absorbance of the first probe light and the second probe light The second absorbance is converted into a converted absorbance based on the relationship with the second absorbance. Then, blood sugar level data is acquired based on the absorbance of a plurality of probe lights including this converted absorbance. As a result, the blood sugar level can be accurately measured without acquiring data for conversion (correction) in advance, while suppressing the influence of the environment around the device, temperature changes in the living body, and the like.

<Functional configuration of processing unit 2f>
First, the functional configuration of the processing section 2f included in the blood sugar level measuring device according to this embodiment will be described with reference to FIG. 36. FIG. 36 is a block diagram illustrating an example of the functional configuration of the processing section 2f. As shown in FIG. 36, the processing section 2f includes a blood sugar level acquisition section 22f. Further, the blood sugar level acquisition section 22f includes a data holding section 223 and an absorbance conversion section 224.

Among these, the function of the data holding unit 223 is realized by the HD 504 (see FIG. 5), and the function of the absorbance converting unit 224 is realized by the CPU 501 executing a predetermined program.

The data holding unit 223 temporarily holds each of the first absorbance data of the first probe light, the second absorbance data of the second probe light, and the third absorbance data of the third probe light input from the absorbance output unit 217. The data holding unit 223 can overwrite and hold the newly input first to third absorbance data after a predetermined period of time has elapsed.

The absorbance conversion unit 224 reads out the first to third absorbance data temporarily held by the data holding unit 223, uses the first absorbance data as reference absorbance data, and converts the first absorbance data into the second absorbance data based on the relationship between the reference absorbance data and the second absorbance data. Converting the absorbance data to second converted absorbance data. Further, the third absorbance data is converted into third converted absorbance data based on the relationship between the reference absorbance data and the third absorbance data. Here, the second converted absorbance data and the third converted absorbance data are each an example of converted absorbance.

Further, in this embodiment, as an example, a probe light with a wave number of 1100 cm-1 is used as the first probe light, a probe light with a wave number of 1050 cm-1 is used as the second probe light, and a probe light with a wave number of 1070 cm-1 is used as the first probe light. 3 probe lights.

After that, the absorbance converting section 224 outputs each of the first absorbance data, the second converted absorbance data, and the third converted absorbance data to the biological information output section 221. The biological information output unit 221 uses these as input data to acquire blood sugar level data based on the normalized MLR model of equation (4) described above. The normalized MLR model expressed by equation (4) is an example of a linear model.

<Action of the absorbance converter 224>
Next, the function of the absorbance converter 224 will be explained. First, the correlation between the second absorbance and the third absorbance with respect to the reference absorbance will be described.

In order to investigate this correlation, the first to third absorbances were measured using the subject's lips, which corresponds to the living body S, several dozen times from before the meal until 3 hours had passed after the meal. did. FIG. 37 is a diagram showing the correlation between the second absorbance and the third absorbance with respect to the reference absorbance. The horizontal axis in FIG. 37 indicates the reference absorbance. Moreover, the plot of black dots indicates the second absorbance, and the plot of white dots indicates the third absorbance.

The measured absorbance varies depending on the contact state between the living body S and the ATR prism 16, the detection sensitivity of the photodetector 17, etc., but on average, the second absorbance and the third absorbance are each proportional to the reference absorbance. It is thought that then. However, as shown in FIG. 37, the regression line 371 (solid regression line) of the second absorbance with respect to the standard absorbance and the regression line 372 (broken line regression line) of the third absorbance with respect to the standard absorbance have different intercept values. There is. Specifically, the intercept of the regression line of the second absorbance is 0.187, and the intercept of the regression line of the third absorbance is 0.217.

It is thought that such a deviation of the intercept is caused by factors such as the temperature of the surrounding environment of the apparatus, the difference in sensitivity of the photodetector 17 due to the difference in wavelength, and the drift of the zero point. Therefore, in this embodiment, the second and third absorbance data are converted so as to correct this deviation of the intercept.

Furthermore, in the normalized MLR model, if the measurement sensitivity differs depending on the wavelength of the probe light, the blood glucose level data acquired based on the absorbance will change. This measurement sensitivity corresponds to the slope of the regression line, and in the example of FIG. 37, the slope of the regression line 371 is 0.883, and the slope of the regression line 372 is 0.872, indicating that the measurement sensitivity is different. . Therefore, in this embodiment, the second and third absorbance data are converted so as to correct this deviation in slope.

The following equations (6) and (7) show conversion formulas for performing a conversion process to correct such a deviation between the intercept and the slope.

但し、（６）式におけるａ１０５０_ｃは変換後の第２吸光度データ（第２変換吸光度データ）、ａ_１０５０は変換前の第２吸光度データ、ｃ１０５０は回帰直線３７１の切片、ｋ１０５０は回帰直線３７１の傾きをそれぞれ表している。また、（７）式におけるａ１０７０_ｃは変換後の第３吸光度データ（第３変換吸光度データ）、ａ_１０７０は変換前の第３吸光度データ、ｃ１０７０は回帰直線３７２の切片、ｋ１０７０は回帰直線３７２の傾きをそれぞれ表している。

However, a1050_c in equation (6) is the second absorbance data after conversion (second converted absorbance data), a_1050 is the second absorbance data before conversion, c1050 is the intercept of the regression line 371, and k1050 is the slope of the regression line 371. each represents. In addition, a1070_c in equation (7) is the third absorbance data after conversion (third converted absorbance data), a_1070 is the third absorbance data before conversion, c1070 is the intercept of the regression line 372, and k1070 is the slope of the regression line 372. each represents.

This second converted absorbance data and third converted absorbance data are input into the normalized MLR model. Note that the coefficients of each term in the normalized MLR model of equation (4) are determined in advance to correspond to the converted absorbance data.

Here, in FIG. 37, an example is shown in which the absorbance was measured several dozen times from before the meal to 3 hours after the meal in order to obtain correlation data of the second absorbance and the third absorbance with respect to the reference absorbance. Indicated. However, even if the absorbance is measured a smaller number of times, it is possible to obtain correlation data of each of the second absorbance and the third absorbance with respect to the reference absorbance.

FIG. 38 is a diagram showing the reference absorbance, second absorbance, and third absorbance in one absorbance measurement. Absorbance data is sampled multiple times in one absorbance measurement, and the horizontal axis in FIG. 38 shows the number of samplings, and the vertical axis shows the absorbance. In the example shown in FIG. 38, the number of samplings in one absorbance measurement is approximately 120 times. Moreover, the graph of FIG. 38 shows the measurement results of the reference absorbance, the second absorbance, and the third absorbance in a mixed manner.

When the number of samplings is about 15, the ATR prism 16 comes into contact with the lips, and the absorbance increases thereafter. However, the absorbance does not remain constant after contact, but gradually increases. This is due to a change in the contact state between the ATR prism 16 and the lips, or a change in temperature of the ATR prism 16 or the lips due to the ATR prism 16 coming into contact with the lips. Note that the time required for this one measurement is about 1 minute.

FIG. 39 shows the respective correlations of the second absorbance and the third absorbance with respect to the reference absorbance, which were obtained using the measurement results of FIG. 38. Since the view of FIG. 39 is the same as that of FIG. 37, redundant explanation will be omitted here.

As shown in FIG. 39, a regression line 371 of the second absorbance and a regression line 372 of the third absorbance can be obtained even with one absorbance measurement. Second converted absorbance data can be obtained using the slope and intercept of the regression line 371, and third converted absorbance data can be obtained using the slope and intercept of the regression line 372.

In the blood sugar level measurement in this embodiment, the absorbance conversion unit 224 reads out the plurality of first to third absorbance data temporarily held by the data holding unit 223. Then, second converted absorbance data is obtained using the slope and intercept of the regression line 371 of the second absorbance data obtained using the first absorbance data as reference absorbance data. Further, third converted absorbance data is obtained using the slope and intercept of the regression line 372 of the third absorbance data obtained using the first absorbance data as reference absorbance data.

In this way, the effects of the temperature of the surrounding environment of the device, the sensitivity difference of the photodetector 17 due to the difference in wavelength, the drift of the 0 point, etc. can be eliminated without acquiring data for conversion (correction) in advance. Absorbance data can be transformed to correct.

<Operations and effects according to the sixth embodiment>
As explained above, in the present embodiment, the first probe light of the first probe light is selected from among the plurality of probe lights including the first probe light and the second probe light having a different wavelength from the first probe light. Using the absorbance data and the second absorbance data of the second probe light, a regression line 371 as an example of the first absorbance and the second absorbance is determined. Then, the second absorbance data is converted to second converted absorbance data using the slope and intercept of the regression line 371, and the blood sugar level is measured based on the absorbance data of the plurality of probe lights including the second converted absorbance data.

Since data for conversion (correction) obtained in advance is not used, even if the measurement conditions change moment by moment due to changes in the surrounding environment of the device or the temperature of the living body, the temperature of the surrounding environment of the device or the living body will be adjusted accordingly. The second absorbance data can be converted to second converted absorbance data to correct for changes and the like. This makes it possible to suppress the effects of changes in the environment around the device and the temperature of the living body, and to accurately measure blood sugar levels.

Here, in this embodiment, an example of the conversion process using the slope and intercept of the regression line has been shown, but the present invention is not limited to this. Some photodetectors 17 have nonlinear sensitivity characteristics, so in such cases, conversion is performed using at least one of the coefficients of each term in a regression polynomial such as a quadratic or cubic equation. Processing can also be performed. As a result, even if the photodetector 17 has nonlinear sensitivity characteristics, it is possible to more precisely suppress the influence of the surrounding environment of the device, temperature changes in the living body, etc., and accurately measure the blood sugar level.

Further, in the present embodiment, an example has been shown in which the blood sugar level acquisition unit 22f includes the data holding unit 223, but the present invention is not limited to this, and the functions of the data holding unit 223 can be transferred to the data recording unit 216 or an external storage device. etc. may be prepared.

Further, in this embodiment, an example was shown in which the conversion process is performed using both the slope and the intercept, but the conversion process may be performed using at least one of the slope and the intercept.

Although the embodiments have been described above, the present invention is not limited to the above specifically disclosed embodiments, and various modifications and changes can be made without departing from the scope of the claims. be.

In the embodiment, an example has been shown in which one processing section 2 implements the functions of the absorbance acquisition section 21, the blood sugar level acquisition section 22, the drive control section 23, etc., but the present invention is not limited to this. These functions may be realized by separate processing sections, or the functions of the absorbance acquisition section 21 and the blood sugar level acquisition section 22 may be realized by being distributed among a plurality of processing sections. Further, it is also possible to adopt a configuration in which the functions of the processing unit and the functions of the storage device such as the data recording unit 216 are realized by an external device such as a cloud server.

Further, in the embodiment, an example has been shown in which the first light source 111, the second light source 112, and the third light source 113 are provided as a plurality of light sources, and each of them emits light of a different wavelength in the mid-infrared region. It is not limited. One light source may emit light of multiple wavelengths.

Furthermore, although a quantum cascade laser is shown as an example of a light source, it is not limited to this, and light sources other than lasers such as infrared lamps, LEDs (Light Emitting Diodes), and SLDs (Super Luminescent Diodes) may also be used. can. In this case, it is preferable to make the probe light enter a total reflection member such as the ATR prism 16 via a wavelength filter that extracts only the desired wavelength. Alternatively, it is preferable that the photodetector 17 receives the probe light through a wavelength filter.

Further, in the embodiment, an example of measuring blood sugar level as biological information is shown, but the embodiment is not limited to this, and as long as it can be measured based on absorbance, the embodiment can be applied to measurement of other biological information. can.

In addition, an optical element such as a beam splitter that splits a part of the probe light after it is emitted from a light source or a hollow optical fiber, and a detection element that detects the intensity of the part of the branched probe light are used. The drive voltage or drive current of the light source may be feedback-controlled so as to suppress fluctuations in probe light intensity. This suppresses fluctuations in the output of the light source and enables more accurate measurement of biological information.

Further, although an example has been shown in which the total reflection member is composed of the ATR prism 16, the present invention is not limited to this. The total reflection member may be constructed using a parallel plate, an optical fiber, or the like, as long as it can cause total reflection and allow the field to seep out during total reflection.

Further, although an example has been described in which the second to sixth embodiments are applied to the configuration of the blood glucose level measuring device 100 according to the first embodiment, the present invention is not limited thereto. The second to fourth embodiments can also be applied to the case where the blood glucose level measuring device includes one light source and the first to third probe lights having different wavelengths are emitted from the one light source to perform measurement. In that case, since there is no need to switch the incidence of the first to third probe lights onto the ATR prism 16, the blood sugar level measuring device uses the first shutter 121, the second shutter 122, the third shutter 123, and the first half mirror 131. Also, the second half mirror 132 may not be provided.

Further, each of the second to fifth embodiments can be applied to the case where the blood sugar level measuring device includes one light source and the measurement is performed by emitting probe light of one wavelength from the one light source.

Further, the second to sixth embodiments are also applied to absorbance measurement and biological information measurement when the light intensity of the first to third probe lights is not corrected using the detected value by the photodetector 17 during the non-incidence period. be able to.

Furthermore, a blood glucose level measuring device may be configured by combining a plurality of the first to sixth embodiments.

Embodiments also include a method of measuring absorbance. For example, the absorbance measuring method includes a step of emitting a plurality of probe lights having different wavelengths in a specific wavelength region, a step of totally reflecting the incident probe light by a total reflection member while in contact with the object to be measured, and a step of controlling the incidence of the probe light on the total reflection member so that there is at least a period in which all of the plurality of probe lights do not enter the total reflection member; and the probe light emitted from the total reflection member. a process using a light intensity detection unit provided to be able to detect the light intensity of the probe light, a detected value by the light intensity detection unit in a state in which the probe light is incident on the total reflection member, and a detection value of all of the plurality of probe lights. and outputting an absorbance obtained based on the detected value in a state where the light does not enter the total reflection member. With such an absorbance measuring method, it is possible to obtain the same effects as the absorbance device according to the first embodiment.

Further, the absorbance measurement method includes a step of emitting probe light in a specific wavelength range, a step of totally reflecting the incident probe light by a total reflection member while in contact with the object to be measured, and a step of A step of guiding each probe light to the total reflection member, a step of driving the light guide section, a step of controlling the drive of the light guide section, and a step of light of the probe light emitted from the total reflection member. A detection step of detecting the intensity and a step of outputting the absorbance of the probe light obtained based on the light intensity are performed. With such an absorbance measuring method, it is possible to obtain the same effects as the absorbance device according to the second embodiment.

Further, the biological information measuring method includes a step of emitting probe light in a specific wavelength range, a step of totally reflecting the incident probe light by a total reflection member while in contact with a measured object, and a step of totally reflecting the incident probe light from the total reflection member. a step of detecting the light intensity of the emitted probe light; and a step of outputting biological information acquired based on the light intensity and the temperature of at least one of the object to be measured or the total reflection member. conduct. With such a biological information measuring method, it is possible to obtain the same effects as the biological information measuring device according to the fifth embodiment.

Further, the biological information measuring method includes a step of emitting a plurality of probe lights including a first probe light and a second probe light having a different wavelength from the first probe light, and a step of emitting a plurality of probe lights including a first probe light and a second probe light having a different wavelength from the first probe light, and a step of detecting a light intensity of the probe light; a step of obtaining an absorbance of the probe light based on the light intensity; a first absorbance of the first probe light; and a second absorbance of the second probe light. Based on the relationship, a step of converting the second absorbance to a converted absorbance, and a step of outputting biological information acquired based on the absorbance of the plurality of probe lights including the converted absorbance are performed. With such a biological information measuring method, it is possible to obtain the same effects as the biological information measuring device according to the sixth embodiment.

Moreover, each function of the embodiment described above can be realized by one or more processing circuits. Here, the term "processing circuit" as used herein refers to a processor programmed to execute each function by software, such as a processor implemented by an electronic circuit, or a processor designed to execute each function explained above. This includes devices such as ASICs (Application Specific Integrated Circuits), DSPs (digital signal processors), FPGAs (field programmable gate arrays), and conventional circuit modules.

1 Measuring unit 100 Blood sugar level measuring device (an example of a biological information measuring device)
101 Absorbance measuring device 111 First light source (an example of a light source)
112 Second light source (an example of a light source)
113 Third light source (an example of a light source)
121 First shutter 122 Second shutter 123 Third shutter 131 First half mirror 132 Second half mirror 14 Coupling lens 151 First hollow optical fiber (an example of a light guiding part)
152 Second hollow optical fiber 153 Light guide support member 154 Output support member 16 ATR prism (an example of a total reflection member)
161 Incident surface 162 First total reflection surface 162m, 163m Reflective film (an example of area defining part)
162k, 163k Field 163 Second total reflection surface 164 Output surface 17 Photodetector (an example of a light intensity detection section)
181 Piezoelectric drive unit (an example of a drive unit)
1820 Piezoelectric drive unit (an example of a drive unit)
1821 Motor (an example of a drive part)
1822 MEMS mirror (an example of a driving part)
191 Deflection mirror (an example of a deflection part)
192 First condensing lens 193 Second condensing lens (an example of a condensing part)
2 Processing unit 21 Absorbance acquisition unit 211 Light source drive unit 212 Light source control unit 213 Shutter drive unit 214 Shutter control unit (an example of an incident control unit)
215 Data acquisition section 216 Data recording section 217 Absorbance output section 218 Notification section 219 Pressure correction section 22 Blood sugar level acquisition section 221 Biological information output section 222 Temperature correction section 223 Data holding section 224 Absorbance conversion section 23 Drive control section 30 Pressure sensor (pressure Example of detection part)
31 Total reflection support part 50 Temperature sensor (an example of a temperature detection part)
501 CPU
506 Display 519 Detection I/F
85 cycle (example of 1 cycle)
86 period (an example of the first incident period)
87 Period (an example of the second incident period)
84, 88 Non-incident period S Living body (example of object to be measured)
P Probe light Pr Contact pressure (an example of pressure)
y Blood sugar level data before correction y_c Blood sugar level data after correction T Sublingual body temperature

JP2004-329888A

Claims (22)

a light source that emits a plurality of probe lights including a first probe light and a second probe light having a different wavelength from the first probe light;
a light intensity detection unit that detects the light intensity of the probe light absorbed by the object to be measured;
an absorbance acquisition unit that acquires absorbance data of the probe light absorbed by the object to be measured based on the light intensity;
a data holding unit that temporarily holds a plurality of first absorbance data of the first probe light and a plurality of second absorbance data of the second probe light acquired by the absorbance acquisition unit;
Information indicating a relationship between the first absorbance and the second absorbance, which is obtained using a plurality of data on the first absorbance and a plurality of data on the second absorbance, which are temporarily held by the data holding unit . an absorbance conversion unit that converts the second absorbance into a converted absorbance that corrects the absorbance shift based on;
A biological information measuring device comprising: a biological information output section that outputs biological information acquired based on the absorbance of the plurality of probe lights including the converted absorbance. The information indicating the relationship between the first absorbance and the second absorbance includes a regression line between the first absorbance and the second absorbance,
The biological information measuring device according to claim 1 , wherein the absorbance converter converts the second absorbance into the converted absorbance based on at least one of a slope or an intercept in the regression line. The information indicating the relationship between the first absorbance and the second absorbance includes a regression polynomial of the first absorbance and the second absorbance,
The biological information measuring device according to claim 1 , wherein the absorbance converter converts the second absorbance into the converted absorbance based on at least one of the coefficients of each term in the regression polynomial. The biological information output section includes:
The biological information measuring device according to any one of claims 1 to 3 , which outputs the biological information acquired based on a linear model using the absorbance of the plurality of probe lights as input data. The biological information measuring device according to any one of claims 1 to 4 , further comprising a temperature detection section that detects the temperature of the object to be measured. comprising a total reflection member that totally reflects the probe light that is incident while in contact with the object to be measured;
The biological information measuring device according to any one of claims 1 to 5 , wherein the light intensity detection section detects the light intensity of the probe light emitted from the total reflection member. comprising an entrance control unit that controls the incidence of the probe light on the total reflection member so that there is at least a period in which all of the plurality of probe lights do not enter the total reflection member;
The light intensity detection unit is provided to be able to detect the light intensity of the probe light emitted from the total reflection member,
The biological information output unit is configured to detect the biological information obtained based on the light intensity of the probe light and a detection value by the light intensity detection unit in a state in which all of the plurality of probe lights do not enter the total reflection member. The biological information measuring device according to claim 6 , which outputs information. 8. The biological information measuring device according to claim 6, wherein the total reflection member includes an area defining section that defines a measurement sensitivity area on the total reflection surface that the object to be measured comes into contact with . The biological information measuring device according to claim 8 , wherein the region defining section defines the measurement sensitivity region by totally reflecting the probe light in the measurement sensitivity region. The biological information measuring device according to claim 8 or 9 , wherein the area defining section defines the measurement sensitivity area provided in an area other than an end of the total reflection surface. a light guide section that guides the probe light to the total reflection member;
a driving section that drives the light guide section;
The biological information measuring device according to any one of claims 6 to 10 , further comprising a drive control section that controls the drive section. The biological information measuring device according to claim 11 , wherein the drive section changes at least one of a position or an angle of the light guide section. The biological information measuring device according to claim 11 or 12 , further comprising a light guide support section that supports the total reflection member and the light guide section. The total reflection member includes an entrance surface on which the probe light enters,
The biological information measuring device according to any one of claims 6 to 13 , wherein the incident surface is a diffusing surface. The total reflection member includes an entrance surface on which the probe light enters,
The biological information measuring device according to any one of claims 6 to 14 , wherein the entrance surface has a curvature. comprising a pressure detection unit that detects the pressure of the object to be measured with respect to the total reflection member,
The biological information output unit outputs the biological information acquired based on the light intensity and the pressure.
The biological information measuring device according to any one of claims 6 to 15. The biological information measuring device according to any one of claims 1 to 16, wherein the light source changes the light intensity of at least one of the plurality of probe lights at a predetermined period. The biological information measuring device according to any one of claims 1 to 17 , wherein the light source changes the light intensity of at least one of the plurality of probe lights in three or more stages. The biological information measuring device according to any one of claims 1 to 18 , wherein the biological information is blood sugar level information. The biological information measuring device according to claim 19 , wherein the wave number of the probe light includes at least one of 1050 cm-1, 1070 cm-1, and 1100 cm-1. The biological information output section includes:
The biological information measuring device according to any one of claims 1 to 20 , which outputs the biological information acquired based on the absorbance and the temperature of the object to be measured. emitting a plurality of probe lights including a first probe light and a second probe light having a different wavelength from the first probe light;
detecting the light intensity of the probe light absorbed by the object to be measured;
acquiring absorbance data of the probe light absorbed by the object to be measured based on the light intensity by an absorbance acquisition unit;
Temporarily holding, by a data holding unit, a plurality of first absorbance data of the first probe light and a plurality of second absorbance data of the second probe light, which are acquired by the absorbance acquisition unit; ,
Information indicating a relationship between the first absorbance and the second absorbance, which is obtained using a plurality of data on the first absorbance and a plurality of data on the second absorbance, which are temporarily held by the data holding unit . Converting the second absorbance to a converted absorbance in which the absorbance shift is corrected based on
A biological information measuring method that performs the step of outputting biological information acquired based on the absorbance of the plurality of probe lights including the converted absorbance.

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