JP2007144103A - Biological component concentration measuring device - Google Patents

Abstract

A biological component concentration measuring apparatus capable of sufficiently measuring emitted light from the eardrum and capable of improving the measurement accuracy of biological information.
An insertion probe 104 to be inserted into an ear canal, an optical path changing element 105 provided at a distal end portion of the insertion probe 104 and having an incident surface on which infrared light emitted from the eardrum is incident, and the infrared light For each wavelength, an infrared detector for detecting the infrared light dispersed by the spectroscopic element, and a biological component concentration calculation unit for converting the output of the infrared detector into a biological component concentration The optical path changing element 105 changes the optical path of the infrared light so that the infrared light passes through the insertion probe 104.
[Selection] Figure 1

Description

  The present invention relates to a biological component concentration measuring apparatus that non-invasively measures a concentration of a biological component, for example, a glucose concentration, without collecting blood.

Conventionally, as a biological information measuring device, a noninvasive blood glucose meter has been proposed that measures the emitted light from the eardrum and calculates the glucose concentration (see, for example, Patent Documents 1, 2, or 3). For example, Patent Document 1 includes a mirror that is large enough to fit in the ear canal. Through the mirror, the eardrum is irradiated with near-infrared rays or heat rays, and light reflected from the eardrum is detected. A non-invasive blood glucose meter for calculating the value is disclosed. Patent Document 2 includes a probe that is inserted into the ear canal, and detects infrared rays generated from the inner ear and emitted from the eardrum through the probe in a state where the eardrum and the ear canal are cooled. A non-invasive blood glucose meter that obtains a glucose concentration by spectroscopic analysis is disclosed. Further, Patent Document 3 includes a reflecting mirror inserted into the ear canal, detects the emitted light from the eardrum using the reflecting mirror, and obtains the glucose concentration by spectroscopic analysis of the detected emitted light. An invasive blood glucose meter is disclosed.
JP 05-506171 JP-T-2002-513604 JP-T-2001-503999

  However, the conventional configuration has a problem that it is difficult to sufficiently detect the emitted light from the eardrum existing behind the ear canal because the ear canal is bent behind the ear canal.

  In view of the above-described conventional problems, the present invention provides a biological component concentration measuring apparatus that can sufficiently measure the emitted light from the eardrum and can improve the measurement accuracy of the biological component concentration. Objective.

  In order to solve the above-described conventional problems, the biological component concentration measuring apparatus of the present invention is provided with an insertion probe to be inserted into the ear canal and an infrared light emitted from the eardrum, which is provided at the distal end of the insertion probe. An optical path changing element having an incident surface, a spectroscopic element that divides the infrared light for each wavelength, an infrared detector that detects the infrared light dispersed by the spectroscopic element, and an output of the infrared detector A biological component concentration calculation unit that converts the concentration into a component concentration, and the optical path changing element changes an optical path of the infrared light so that the infrared light passes through the insertion probe.

  According to the biological component concentration measuring apparatus of the present invention, it is possible to sufficiently measure the emitted light from the eardrum and improve the measurement accuracy of the biological component concentration.

  The biological component concentration measuring apparatus of the present invention includes an insertion probe that is inserted into an ear canal, an optical path changing element that is provided at a distal end portion of the insertion probe and has an incident surface on which infrared light emitted from the eardrum is incident, A spectroscopic element that splits infrared light into each wavelength, an infrared detector that detects the infrared light split by the spectroscopic element, and a biocomponent concentration calculation unit that converts the output of the infrared detector into a biocomponent concentration The optical path changing element changes the optical path of the infrared light so that the infrared light passes through the insertion probe.

  With this configuration, since the optical path of infrared light emitted from the eardrum is changed by the optical path changing element so as to pass through the insertion probe, more infrared light is transmitted by infrared rays than when no optical path changing element is provided. Since it reaches the detector, the infrared light emitted from the eardrum can be sufficiently measured, and the measurement accuracy of the biological component concentration can be improved.

  The optical path changing element has a refractive index higher than that of air, and refracts the infrared light at the incident surface, thereby changing the optical path of the infrared light so that the infrared light passes through the insertion probe. It may be changed.

  In this case, as the material of the optical path changing element, a material transparent in the infrared region, such as ZnSe, diamond, AgClBr, can be used.

  Here, the incident surface on which the infrared light emitted from the eardrum enters the optical path changing element and the outgoing surface from which the optical path changing element exits are not parallel to each other, and the angle θ formed by both surfaces may be greater than 0 degrees. preferable.

  The optical path changing element preferably has a plurality of incident surfaces. In this case, since the volume is reduced as compared with the optical path changing element having one incident surface, the cost of the biological component concentration measuring apparatus can be reduced.

  The optical path changing element further includes a reflecting surface, and the infrared light incident from the incident surface is reflected by the reflecting surface, so that the infrared light passes through the insertion probe. The optical path of infrared light may be changed.

  In this case, as the material of the optical path changing element, resin molding is easy and a transparent material in the infrared region and the visible region is preferable. For example, polycarbonate, polypropylene, polyethylene, or the like can be used.

  Here, it is preferable that the optical path changing element has a projection having a triangular or trapezoidal cross section, and a reflecting mirror is provided on one side of the projection to reflect infrared light. The reflecting mirror can be formed by coating a material such as gold or aluminum after the optical path changing element is formed by resin formation.

  The biological component concentration measuring apparatus of the present invention further includes a support portion that holds the optical path changing element, and the optical path changing element is arranged at the distal end portion of the insertion probe by attaching the support portion to the distal end portion of the insertion probe. It is preferable. If it does in this way, an optical path changing element can be easily arranged at the tip part of an insertion probe.

  It is preferable that the optical path changing element and the holding base have an integral structure. In this way, the number of parts is reduced, which is useful for mass production.

  The infrared detector is not particularly limited as long as it can detect light having a wavelength in the infrared region. For example, a pyroelectric sensor, a thermopile, a bolometer, an HgCdTe (MCT) detector, a Golay cell, or the like can be used.

  As the biological component concentration calculation unit, for example, a microcomputer such as a CPU (Central Processing Unit) can be used.

  The insertion probe may be any probe that can guide infrared rays. For example, a hollow tube or an optical fiber that transmits infrared rays can be used. When using a hollow tube, it is preferable to have a gold layer on the inner surface of the hollow tube. This gold layer can be formed by performing gold plating on the inner surface of the hollow tube or by depositing gold.

  When an optical fiber is used, it is preferably a transparent material from visible light to infrared wavelengths in the mid-infrared region. An example of such a material is an AgCl-AgBr solid solution. When using an optical fiber, it is preferable to use a bundle fiber obtained by bundling a plurality of optical fibers and bonding and polishing the end portions of the optical fibers. In this case, since the number of optical fibers is increased, the eardrum can be imaged with a resolution corresponding to the number of optical fibers when the eardrum is imaged by the imaging device.

  The biological component concentration measuring apparatus according to the present invention includes a light source that emits light for illuminating the inside of the ear canal, an image sensor that images the light emitted from the light source and reflected in the ear canal, and the image sensor. From the obtained imaging information, an imaging information detection unit that detects imaging information of the eardrum, and infrared light emitted from the eardrum is selected based on the imaging information of the eardrum detected by the imaging information detection unit And an optical path control element that controls the optical path so as to transmit light.

  With this configuration, infrared light emitted from the eardrum passes through the optical path control element and reaches the infrared detector, and infrared light emitted from the ear canal is blocked by the optical path control element and does not reach the infrared detector. Can be removed, and highly accurate measurement can be performed.

  As the light source, for example, a visible light laser such as a red laser, a white LED, or the like can be used. Among these, a white LED is preferable because it generates less heat when it emits light than a halogen lamp, and thus has little influence on the temperature of the eardrum or ear canal.

  As the image pickup element, for example, an image element such as a CMOS or a CCD can be used.

  As the optical path control element, a liquid crystal shutter, a mechanical shutter, or the like can be used. As the liquid crystal shutter, for example, it is preferable that the liquid crystal shutter includes a TFT, and can control infrared light in a specific region or can be shielded by controlling using a TFT (Thin Film Transistor).

  As the mechanical shutter, for example, a digital mirror device (hereinafter abbreviated as DMD) in which micro mirror surfaces (micro mirrors) are arranged in a plane can be used. The DMD can be manufactured using a known MEMS (Micro Electro Mechanical System) technique. Each micromirror can be controlled to two states, ON and OFF, by driving an electrode provided in the lower part of the mirror surface. When the micromirror is ON, the infrared light emitted from the eardrum is reflected and projected toward the infrared detector. When the micromirror is OFF, the infrared light is reflected toward the absorber provided inside the DMD. However, it is not projected toward the infrared detector. Therefore, by individually driving each micromirror, it is possible to control the projection of infrared light for each minute region.

  As the imaging information detection unit, for example, a microcomputer such as a CPU (Central Processing Unit) can be used.

  As a method for the imaging information detection unit to detect imaging information of the eardrum from imaging information obtained by the imaging device, image processing of the imaging information obtained by the imaging device is performed, and a color difference between the eardrum and the ear canal is calculated. A method for recognizing an image of the eardrum by using it is mentioned.

  The biological component concentration measuring apparatus of the present invention may further include a light splitting element that transmits one of the light reflected in the ear canal and the infrared light emitted from the eardrum and reflects the other. .

  Here, the spectroscopic element may be arranged between the infrared detector and the light splitting element.

In the present invention, as the light splitting element, for example, a half mirror having a function of transmitting one of visible light and infrared light and reflecting the other can be used. In the case of reflecting visible light and transmitting infrared light, for example, ZnSe, CaF ₂ , Si, Ge, or the like can be used as the material of the half mirror. Moreover, you may use what provided the layer which consists of aluminum and gold | metal | money of several nanometers thickness on resin transparent with respect to infrared rays. Examples of the resin that is transparent to infrared rays include polycarbonate.

  Any spectroscopic element may be used as long as it can divide infrared rays by wavelength. For example, an optical filter that transmits infrared rays in a specific wavelength region, a Michelson interferometer, a diffraction grating, or the like can be used.

  The imaging information detection unit calculates a ratio of the imaging information of the eardrum in the imaging information obtained by the imaging element, and the biological component concentration calculation unit uses the ratio to output the output of the infrared detector. It is preferable to correct. The intensity of infrared light emitted from a living body depends on the area of the portion where infrared light is emitted. Therefore, even when the area of the eardrum imaged by the image sensor varies, this correction reduces the variation in the measurement result and enables more accurate measurement.

  The biological component concentration measuring apparatus of the present invention preferably further includes a warning output unit that outputs a warning when the ratio is equal to or less than a threshold value. With this configuration, it is possible to notify the user that the position of the biological component concentration measuring device is inappropriate.

  Here, examples of the warning output unit include a display that displays a warning, a speaker that outputs a warning by voice, and a buzzer that generates a warning sound.

  The biological component concentration measuring apparatus of the present invention may further include an audio output unit that outputs audio when imaging information of the eardrum is detected by the imaging element. Here, it is preferable that the sound output unit changes the frequency or intensity of the sound in accordance with the size of the area of the eardrum imaged by the image sensor.

  The biological component concentration measuring apparatus of the present invention includes a storage unit that stores correlation data indicating the correlation between the output signal of the infrared detector and the biological component concentration, and a display that displays the concentration of the biological component converted by the biological component concentration calculation unit. And a power source for supplying power for operating the biological component concentration measuring apparatus.

  The biological component concentration calculation unit may convert the output signal of the infrared detector into the concentration of the biological component by reading the correlation data from the storage unit and referring to the correlation data.

  The correlation data indicating the correlation between the output signal of the infrared detector and the biological component concentration is obtained by measuring the output signal of the infrared detector for a patient having a known biological component concentration (for example, blood glucose level), for example. It can be obtained by analyzing the correlation between the output signal of the detector and the concentration of the biological component.

  In the present invention, for example, a memory such as a RAM or a ROM can be used as the storage unit.

  As the display unit, for example, a display such as a liquid crystal can be used.

  As the power source, for example, a battery or the like can be used.

  Examples of the biological component concentration measured by the biological component concentration measuring apparatus of the present invention include glucose concentration (blood glucose level), hemoglobin concentration, cholesterol concentration, and neutral fat concentration.

  By measuring infrared light emitted from a living body, biological information, for example, blood glucose level can be measured. Radiant energy W of infrared radiation from a living body is expressed by the following mathematical formula.

here,
W: radiant energy of infrared radiation from a living body,
ε (λ): emissivity of a living body at wavelength λ,
W ₀ (λ, T): wavelength λ, blackbody radiation intensity density at temperature T,
h: Planck's constant (h = 6.625 × 10 ⁻³⁴ (W · S ² )),
c: speed of light (c = 2.998 × 10 ¹⁰ (cm / s)),
λ ₁ , λ ₂ : wavelength of infrared radiation from the living body (μm),
T: temperature of living body (K),
S: Detection area (cm ² )
k: Boltzmann constant,
It is.

  As can be seen from (Equation 1), when the detection area S is constant, the radiation energy W of the infrared radiation from the living body depends on the emissivity ε (λ) of the living body at the wavelength λ. From Kirchhoff's law of radiation, the emissivity and absorptivity at the same temperature and wavelength are the same.

here,
α (λ): Absorption rate of living body at wavelength λ,
It is.

  Therefore, it can be seen that the absorptance should be considered when considering the emissivity. From the law of conservation of energy, the following relationship holds for the absorptance, transmittance, and reflectance.

here,
r (λ): Biological reflectance at wavelength λ t (λ): Biological transmittance at wavelength λ Therefore, emissivity is calculated using transmittance and reflectance.

It is expressed.

  The transmittance is represented by the ratio between the incident light amount and the transmitted light amount when it passes through the measurement object. The amount of incident light and the amount of light transmitted through the object to be measured are expressed by the Lambert-Beer law.

here,
I _t: the amount of transmitted light,
I ₀ : incident light quantity,
d: thickness of the living body,
k (λ): extinction coefficient of living body at wavelength λ,
It is. The extinction coefficient of a living body is a coefficient representing light absorption by the living body.

  Therefore, the transmittance is

It is expressed.

  Next, the reflectance will be described. As the reflectance, it is necessary to calculate an average reflectance in all directions, but here, for simplicity, the reflectance with respect to normal incidence is considered. The reflectivity for normal incidence is 1 for the refractive index of air.

It is expressed.

here,
n (λ): refractive index of the living body at wavelength λ,
It is.

  From the above, the emissivity is

It is expressed.

  When the concentration of the component in the living body changes, the refractive index and extinction coefficient of the living body change. The reflectance is usually as small as about 0.03 in the infrared region, and, as can be seen from (Equation 8), does not depend much on the refractive index and the extinction coefficient. Therefore, even if the refractive index and extinction coefficient change due to changes in the concentration of components in the living body, the change in reflectance is small.

  On the other hand, the transmittance greatly depends on the extinction coefficient, as can be seen from (Equation 7). Therefore, the transmittance changes when the extinction coefficient of the living body, that is, the degree of light absorption by the living body, changes due to the change in the concentration of the components in the living body.

  From the above, it can be seen that the radiant energy of infrared radiation from a living body depends on the concentration of components in the living body. Therefore, the concentration of the component in the living body can be obtained from the radiant energy intensity of the infrared radiation from the living body.

  Further, as can be seen from (Equation 7), the transmittance depends on the thickness of the living body. The thinner the living body is, the greater the degree of change in the transmittance with respect to the change in the extinction coefficient of the living body, making it easier to detect changes in the concentration of components in the living body. Since the eardrum is as thin as about 60 to 100 μm, it is suitable for measuring the concentration of components in the living body using infrared radiation.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment 1)
FIG. 1 is a perspective view showing an appearance of a biological component concentration measuring apparatus 100 according to the first embodiment.

  The biological component concentration measuring apparatus 100 includes a main body 102, an insertion probe 104 provided on a side surface of the main body 102, and an optical path changing element 105 provided at a distal end portion of the insertion probe 104. The optical path changing element 105 is fixed inside a cylindrical support part 107. The support 107 is attached to the distal end of the insertion probe 104 by fitting the wider opening of the support 107 to the distal end of the insertion probe 104. As a material of the optical path changing element 105, for example, a material transparent in the infrared region and the visible region, such as ZnSe, diamond, AgClBr, is preferable.

  The main body 102 has a display 114 for displaying the measurement result of the concentration of the biological component, a power switch 101 for turning on / off the power of the biological component concentration measuring apparatus 100, and a measurement start switch 103 for starting the measurement. Is provided.

  Here, the display 114 corresponds to a display unit in the present invention.

  Next, the internal structure of the main body of the biological component concentration measuring apparatus 100 will be described with reference to FIGS. FIG. 2 is a diagram showing a configuration of the biological component concentration measuring apparatus 100 according to the first embodiment, and FIG. 3 is a perspective view showing the optical filter wheel 106 in the biological component concentration measuring apparatus 100 according to the first embodiment. is there.

  Inside the main body of the biological component concentration measuring apparatus 100 are a chopper 118, a liquid crystal shutter 120, an optical filter wheel 106, an infrared detector 108, a preamplifier 130, a band filter 132, a synchronous demodulator 134, a low pass filter 136, and analog / digital. Converter (hereinafter abbreviated as A / D converter) 138, microcomputer 110, memory 112, display 114, power supply 116, light source 140, first half mirror 142, second half mirror 144, condenser lens 146, imaging An element 148, an actuator 150, a lens frame 152, a position sensor 154, a timer 156, and a buzzer 158 are provided.

  Here, the microcomputer 110 corresponds to an imaging information detection unit and a biological component concentration calculation unit in the present invention.

  The power source 116 supplies AC or DC power to the microcomputer 110. A battery is preferably used as the power source 116.

  The chopper 118 radiates from the eardrum 202, changes the optical path by the optical path changing element 105, enters the insertion probe 104, is guided into the main body 102 by the insertion probe 104, and then moves the second half mirror 144. It has a function of chopping the transmitted infrared light and converting the infrared light into a high-frequency infrared signal. The operation of the chopper 118 is controlled based on a control signal from the microcomputer 110.

  The infrared light chopped by the chopper 118 reaches the optical filter wheel 106.

  As shown in FIG. 3, the optical filter wheel 106 has a first optical filter 122 and a second optical filter 124 fitted in a ring 123. In the example shown in FIG. 3, the first optical filter 122 and the second optical filter 124 that are both semicircular are fitted into the ring 123 to form a disk-shaped member. A shaft 125 is provided at the center. By rotating the shaft 125 as shown by the arrow in FIG. 3, the optical filter through which the infrared light chopped by the chopper 118 passes is switched between the first optical filter 122 and the second optical filter 124. be able to. The rotation of the shaft 125 is controlled by a control signal from the microcomputer 110. The rotation of the shaft 125 is preferably synchronized with the rotation of the chopper 118 and controlled to rotate the shaft 125 180 degrees while the chopper 118 is closed. In this way, when the chopper 118 is opened next, the optical filter through which the infrared light chopped by the chopper 118 passes can be switched to another optical filter. The optical filter wheel 106 corresponds to the spectroscopic element in the present invention.

As a method for producing the optical filter, a known technique can be used without any particular limitation. For example, a vacuum deposition method can be used. The optical filter can be manufactured by stacking ZnS, MgF ₂ , PbTe, or the like on the substrate by vacuum deposition using Si or Ge as the substrate.

  Here, an optical filter having a desired wavelength characteristic is manufactured by controlling the light interference in the laminated thin film by adjusting the film thickness of each layer laminated on the substrate, the order of lamination, the number of laminations, and the like. can do.

  The infrared light transmitted through the first optical filter 122 or the second optical filter 124 reaches the infrared detector 108 including the detection region 126. The infrared light reaching the infrared detector 108 enters the detection region 126 and is converted into an electrical signal corresponding to the intensity of the incident infrared light.

  The electrical signal output from the infrared detector 108 is amplified by the preamplifier 130. From the amplified electrical signal, signals other than the frequency band having the chopping frequency as the center frequency are removed by the band filter 132. Thereby, noise resulting from statistical fluctuations such as thermal noise can be minimized.

  The electric signal filtered by the band filter 132 is demodulated into a DC signal by synchronizing and integrating the chopping frequency of the chopper 118 and the electric signal filtered by the band filter 132 by the synchronous demodulator 134.

  The low-frequency band signal is removed from the electrical signal demodulated by the synchronous demodulator 134 by the low-pass filter 136. Thereby, noise can be further removed.

  The electrical signal filtered by the low-pass filter 136 is converted into a digital signal by the A / D converter 138 and then input to the microcomputer 110. Here, the electrical signal from the infrared detector 108 corresponding to each optical filter is an electrical signal corresponding to the infrared light transmitted through which optical filter by using the control signal of the shaft 125 as a trigger. Can be identified. The period from when the microcomputer outputs a control signal for the shaft 125 to when the next shaft control signal is output is an electrical signal corresponding to the same optical filter. Since the noise is further reduced by calculating the average value after integrating the electrical signals corresponding to the respective optical filters on the memory 112, it is preferable to integrate the measurements.

  In the memory 112, the electrical signal corresponding to the intensity of the infrared light transmitted through the first optical filter 122, the electrical signal corresponding to the intensity of the infrared light transmitted through the second optical filter 124, and the concentration of the biological component are stored. Correlation data indicating the correlation is stored. The microcomputer 110 reads the correlation data from the memory 112, refers to the correlation data, and converts the digital signal per unit time calculated from the digital signal stored in the memory 112 into the concentration of the biological component. The memory 112 corresponds to the storage unit of the present invention.

  The concentration of the biological component converted in the microcomputer 110 is output to the display 114 and displayed.

  The first optical filter 122 has, for example, a spectral characteristic that transmits infrared light in a wavelength band (hereinafter, abbreviated as a measurement wavelength band) including a wavelength that is absorbed by a biological component to be measured. On the other hand, the second optical filter 124 has a spectral characteristic different from that of the first optical filter 122. The second optical filter 124 is, for example, a wavelength band (hereinafter referred to as a reference wavelength) that includes a wavelength that is not absorbed by a biological component that is a measurement target and that is absorbed by another biological component that interferes with the measurement of the target component. It has a spectral characteristic that transmits infrared light (abbreviated as a band). Here, as such other biological components, those having a large amount of components in the living body other than the biological component to be measured may be selected.

  For example, glucose shows an infrared absorption spectrum having an absorption peak near 9.6 μm. Therefore, when the biological component to be measured is glucose, it is preferable that the first optical filter 122 has a spectral characteristic that transmits infrared light in a wavelength band including 9.6 μm.

  On the other hand, proteins that are abundant in the living body absorb infrared light around 8.5 micrometers, and glucose does not absorb infrared light around 8.5 μm. Therefore, it is preferable that the second optical filter 124 has a spectral characteristic that transmits infrared light in a wavelength band including 8.5 μm.

  The electrical signal corresponding to the intensity of the infrared light transmitted through the first optical filter 122 and the electrical signal corresponding to the intensity of the infrared light transmitted through the second optical filter 324 and the biological component stored in the memory 112 Correlation data indicating the correlation with the concentration of can be obtained, for example, by the following procedure.

  First, infrared light emitted from the eardrum is measured for a patient having a known biological component concentration (for example, blood glucose level). At this time, an electrical signal corresponding to the intensity of infrared light in the wavelength band transmitted by the first optical filter 122 and an electrical signal corresponding to the intensity of infrared light in the wavelength band transmitted by the second optical filter 124 Ask for. By performing this measurement for a plurality of patients having different biological component concentrations, the electrical signal corresponding to the intensity of infrared light in the wavelength band transmitted by the first optical filter 122 and the second optical filter 124 are transmitted. It is possible to obtain a data set including an electrical signal corresponding to the intensity of infrared light in the wavelength band and a corresponding biological component concentration.

  Next, the data set thus obtained is analyzed to obtain correlation data. For example, an electrical signal corresponding to the intensity of infrared light in the wavelength band transmitted by the first optical filter 122, and an electrical signal corresponding to the intensity of infrared light in the wavelength band transmitted by the second optical filter 124; Wavelengths transmitted by the first optical filter 122 by performing multivariate analysis using a multiple regression analysis method such as a PLS (Partial Least Squares Regression) method, a neural network method, or the like with respect to biological component concentrations corresponding to them. A function indicating the correlation between the electrical signal corresponding to the intensity of infrared light in the band and the electrical signal corresponding to the intensity of infrared light in the wavelength band transmitted by the second optical filter 124 and the corresponding biological component concentration Can be requested.

  The first optical filter 122 has spectral characteristics that allow infrared light in the measurement wavelength band to pass therethrough, and the second optical filter 124 has spectral characteristics that allow infrared light in the reference wavelength band to pass therethrough. , The electrical signal corresponding to the intensity of infrared light in the wavelength band transmitted by the first optical filter 122 and the electrical signal corresponding to the intensity of infrared light in the wavelength band transmitted by the first optical filter 324 And correlation data indicating the correlation between the difference and the corresponding biological component concentration may be obtained. For example, it can be obtained by performing a linear regression analysis such as a least square method.

  Next, a configuration for imaging the eardrum 202 will be described.

  The light source 140 emits visible light for illuminating the eardrum 202. Visible light emitted from the light source 140 and reflected by the first half mirror 142 is reflected by the second half mirror 144 and then guided through the insertion probe 104 into the ear canal 204 to illuminate the eardrum 202. .

  As the light source 140, for example, a visible light laser such as a red laser, a white LED, or the like can be used. Among these, a white LED is preferable because it generates less heat when it emits light than a halogen lamp, and thus has little influence on the temperature of the eardrum 202 and the ear canal 204.

  The first half mirror 142 has a function of reflecting part of visible light and transmitting the rest.

The second half mirror 144 reflects visible light and transmits infrared light. The material of the second half mirror 144 is preferably a material that does not absorb infrared light, transmits it, and reflects visible light. As a material of the second half mirror 144, for example, ZnSe, CaF ₂ , Si, Ge, or the like can be used. Moreover, you may use what provided the layer which consists of aluminum and gold | metal | money of several nanometers thickness on resin transparent with respect to infrared rays. Examples of the resin transparent to infrared rays include polycarbonate, polypropylene, and polyethylene. Here, the second half mirror 144 corresponds to the light splitting element in the present invention.

  On the other hand, visible light that has entered the insertion probe 104 from the eardrum 202 through the ear canal 204 is reflected by the second half mirror 144, and part of the visible light passes through the first half mirror 142. The visible light that has passed through the first half mirror 142 is collected by the condenser lens 146 held by the lens frame 152 and reaches the image sensor 148.

  As the image sensor 148, for example, an image element such as a CMOS or a CCD is used.

  The biological component concentration measuring apparatus 100 detects the distance from the image sensor 148 to the eardrum 202, drives the condenser lens 146 held by the lens frame 152, and correctly forms an optical image on the image sensor 148. Provide mechanism.

  The actuator 150 is driven by a control signal from the microcomputer 110, and can move the condenser lens 146 in the direction of the optical axis (the direction of the arrow in FIG. 2). At this time, the position sensor 154 detects the position of the condenser lens 146 and outputs it to the microcomputer 110.

  On the other hand, the microcomputer 110 extracts a high-frequency component of a signal from a pixel included in a focusing area near the center of the image sensor 148 using a bandpass filter, and contrasts the extracted component from the magnitude of the extracted component. Detect the amount. The microcomputer 110 controls the actuator 150 so that the condenser lens 146 moves to a position where the contrast amount is maximized.

  In this way, even if the distance to the eardrum 202 changes, an optical image of the eardrum 202 can be correctly formed on the image sensor 148. In this mechanism, the distance to the eardrum 202 is not directly measured, but the distance to the eardrum 202 is indirectly measured from the positional information of the condenser lens 146.

  As the actuator 150 and the position sensor 154, those similar to those used in an autofocus device mounted on a known video camera or digital still camera can be used. For example, the actuator 150 can be composed of a coil provided on the lens frame 152, a yoke fixed to the main body 102 side, and a driving magnet attached to the yoke. When the lens frame 152 is supported by two guide poles so as to be movable in the optical axis direction, and a current is supplied to a coil provided in the lens frame 152, a magnetic circuit formed by a yoke and a driving magnet. A magnetic driving force in the optical axis direction is generated with respect to the coil inside, and the lens frame 152 moves in the optical axis direction. The positive / negative direction of the driving force can be controlled by the direction of the current supplied to the coil.

  The position sensor 154 includes, for example, a sensor magnet that is magnetized at a constant pitch and attached to the lens frame 152, and a magnetoresistive sensor (hereinafter abbreviated as an MR sensor) fixed to the main body 102 side. Can do. The position of the condenser lens 146 can be detected by detecting the position of the sensor magnet attached to the lens frame 152 by the MR sensor fixed on the main body 102 side.

  Next, a method for recognizing the position of the eardrum 202 from an image photographed by the image sensor 148 will be described.

  FIG. 4 is an image diagram showing an image when the inside of the ear canal 200 is observed using the image sensor 148. Although there are individual differences in the shape of the ear canal, it is often bent. FIG. 4 shows an example of imaging the eardrum of a person whose outer ear canal is bent. The left side of the image is the eardrum 202, and the right ear is the ear canal 204. The position and size at which the eardrum 202 is visible vary depending on the individual, but also varies depending on the insertion position of the insertion probe 104.

  The ear canal color is skin color, and the eardrum color is white or colorless and transparent. By recognizing the color difference between the ear canal and the eardrum by the imaging information detection unit, the two can be distinguished and recognized. The image information obtained by the image sensor 148 is subjected to image processing in the microcomputer 110 to extract the region of the eardrum 202 from the image information. As the image processing, for example, the following region extraction technique using threshold processing and labeling processing can be used.

  First, threshold processing is performed on image information. Each pixel of the image has an RGB value, and the average value of the RGB values is the brightness of each pixel. A constant reference value (threshold value) is set for the brightness of the pixel, and the process of converting the brightness of each pixel into two values of black and white by the threshold value is performed. For example, if the brightness of the pixel is equal to or higher than the set threshold, white is set for the pixel, and black is set for the pixel in other cases. Since the pixel of the portion corresponding to the eardrum 202 is brighter than the pixel of the portion corresponding to the ear canal 204, the threshold value is set between the brightness of the pixel corresponding to the eardrum and the brightness of the pixel corresponding to the ear canal. Then, the pixel corresponding to the eardrum 202 is set to white and the pixel corresponding to the ear canal 204 is set to black by the above processing.

  Next, a labeling process is performed on the image information subjected to the above threshold process. For example, all pixels in the threshold-processed image information are scanned, and the same label is added as an attribute to the pixels set to white.

  Through the above processing, the region corresponding to the pixel to which the label is added can be recognized as the eardrum 202. The ratio of the region of the eardrum 202 in the captured image can be obtained by calculating the ratio of the number of pixels with labels to the total number of pixels by the microcomputer 110.

  The liquid crystal shutter 120 has a structure in which a plurality of liquid crystal cells are arranged in a matrix, and each liquid crystal cell is individually divided into a state where light is transmitted and a state where light is blocked by a voltage applied to each liquid crystal cell. Can be controlled. When the microcomputer 110 recognizes an image corresponding to the eardrum 202 from the image information captured by the image sensor 148 by the image processing described above, the microcomputer 110 controls the voltage applied to each liquid crystal cell of the liquid crystal shutter 120 to The liquid crystal cell in which the infrared light is incident is set in a state in which the light is transmitted, and the liquid crystal cell in which the infrared light from other than the eardrum 202 is incident is set in a state in which the light is blocked.

  Thereby, the infrared light emitted from the eardrum 202 can be selectively incident on the infrared detector 108. Here, the liquid crystal shutter 120 corresponds to an optical path control element in the present invention.

  Next, the operation of the biological component concentration measuring apparatus 100 in the present embodiment will be described.

  First, when the user presses the power switch 101 of the biological component concentration measuring apparatus 100, the power supply in the main body 102 is turned on, and the biological component concentration measuring apparatus 100 is in a measurement preparation state.

  Next, the user holds the main body 102 and inserts the insertion probe 104 into the ear hole 200. Since the insertion probe 104 is a conical hollow tube whose diameter increases from the distal end portion of the insertion probe 104 toward the connection portion with the main body 102, the outer diameter of the insertion probe 104 is equal to the inner diameter of the ear hole 200. The insertion probe 104 is not inserted beyond a certain position. At this time, as shown in FIG. 2, the sizes of the insertion probe 104 and the optical path changing element 105 are set so that the optical path changing element 105 arranged at the distal end portion of the insertion probe 104 is positioned in the vicinity of the bent portion of the ear canal 204. It is preferable.

  Next, when the user presses the measurement start switch 103 of the biological component concentration measuring apparatus 100 while holding the biological component concentration measuring apparatus 100 at a position where the outer diameter of the insertion probe 104 is equal to the inner diameter of the ear hole 200, the main body The light source 140 in 102 is turned on, and imaging by the imaging element 148 is started.

  Next, the step of recognizing the position of the eardrum 202 from the image photographed by the image sensor 148 is performed by the above method. As a result of the image recognition, if the microcomputer 110 determines that there is no image corresponding to the eardrum 202 in the image taken by the image sensor 148, a message indicating that the insertion direction of the insertion probe 104 is deviated from the eardrum 202. Is displayed on the display 114, the buzzer 158 is sounded, or the sound is output from a speaker (not shown) to notify the user of an error. Here, when the ratio of the eardrum region in the captured image calculated by the microcomputer 110 is equal to or less than the threshold, the user may be notified of an error. When an error indicating that the position of the eardrum 202 cannot be recognized is notified, the user may adjust the insertion direction of the insertion probe 104 by moving the biological component concentration measuring apparatus 100.

  Here, the display 114, the buzzer 158, and the speaker each correspond to a warning output unit in the present invention.

  When the microcomputer 110 determines that the position of the eardrum 202 has been recognized in the image captured by the image sensor 148 as a result of the image recognition, a message indicating that the position of the eardrum 202 has been recognized is displayed. The information is displayed on the screen 114, the buzzer 158 is sounded, or the sound is output from a speaker (not shown) to notify the user. When the position of the eardrum 202 is recognized, measurement of infrared rays emitted from the eardrum 202 is automatically started. By notifying the user that the position of the eardrum 202 has been recognized, the user can grasp that the measurement has been started. Can be recognized as good.

  Here, the speaker corresponds to an audio output unit in the present invention.

  When the microcomputer 110 determines that the position of the eardrum 202 has been recognized in the image captured by the image sensor 148, the voltage applied to each liquid crystal cell of the liquid crystal shutter 120 is controlled to detect red from the eardrum 202. The liquid crystal cell in which external light is incident is set in a state where light is transmitted, and the liquid crystal cell in which infrared light from other than the eardrum 202 is incident is set in a state where light is blocked. Further, when the microcomputer 110 starts the operation of the chopper 118, measurement of infrared light emitted from the eardrum 202 is started.

  Even after the measurement of infrared light is started, the process for recognizing the position of the eardrum in the image photographed by the image sensor 148 is continued. If the user removes the insertion probe 104 from the ear canal 200 or moves the direction of the insertion probe 104 greatly during measurement, the microcomputer 110 captures an image captured by the image sensor 148. When it is determined that there is no image corresponding to the eardrum 202, an erroneous operation of the user is detected. Along with this detection, the microcomputer 110 displays a message on the display 114 that the insertion direction of the insertion probe 104 is deviated from the eardrum 202, sounds a buzzer 158, and outputs sound from a speaker (not shown). To notify the user of an error. Further, the microcomputer 110 automatically stops the measurement by controlling the chopper 118 to block infrared light reaching the optical filter wheel 106. Here, when the ratio of the eardrum region in the captured image calculated by the microcomputer 110 is equal to or less than the threshold, the user may be notified of an error.

  When an error indicating that the position of the eardrum 202 cannot be recognized is notified, the user moves the biological component concentration measuring apparatus 100 to reinsert the insertion probe 104 into the ear canal 200 or change the insertion direction of the insertion probe 104. After the adjustment, the measurement is started again by pressing the measurement start switch 103.

  When the microcomputer 110 determines that a certain time has elapsed from the start of measurement based on the time signal from the timer 156, the microcomputer 110 controls the chopper 118 to block infrared light reaching the optical filter wheel 106. As a result, the measurement automatically ends. At this time, the microcomputer 110 controls the display 114 and the buzzer 158 to display a message indicating that the measurement is completed on the display 114, to sound the buzzer 158, and to output the sound from a speaker (not shown). To notify the user that the measurement is completed. As a result, the user can confirm that the measurement has been completed, so the insertion probe 104 is taken out of the ear canal 200.

  The electric signal output from the A / D converter 138 is corrected by the microcomputer 110 using the proportion of the eardrum region in the captured image obtained by the above method. The microcomputer 110 transmits an electrical signal corresponding to the intensity of the infrared light transmitted through the first optical filter 122 and an electrical signal corresponding to the intensity of the infrared light transmitted through the second optical filter 124 from the memory 112 and the living body. Correlation data indicating the correlation with the component concentration is read, and the corrected electrical signal is converted into the concentration of the biological component with reference to the correlation data. The obtained concentration of the biological component is displayed on the display 114.

  The method of correcting the electrical signal based on the proportion of the eardrum region in the captured image can be selected according to the content of the electrical signal in the correlation data stored in the memory 112. For example, if the electrical signal in the correlation data stored in the memory 112 is a signal per unit area, the measured electrical signal per unit area is calculated using the ratio of the tympanic region in the captured image. What is necessary is just to correct | amend to a signal. In this way, the measured signal can be corrected by the area of the eardrum from which the measured infrared light has been emitted.

  Next, the optical path changing element 105 will be described in more detail with reference to FIG. FIG. 5 is a cross-sectional view of the optical path changing element in the biological component concentration measuring apparatus according to the present embodiment. In FIG. 5, the arrow indicates the optical path of infrared light. An example in which ZnSe is used as the material of the optical path changing element 105 will be described.

  The optical path changing element 105 of the biological component concentration measuring apparatus according to this embodiment has a cross section perpendicular to the incident surface 502 on which infrared light emitted from the eardrum 202 is incident and the emission surface 504 from which infrared light is emitted. It has a trapezoidal shape. That is, the incident surface 502 and the exit surface 504 are not parallel, and the angle formed by both surfaces is greater than 0 degrees.

Since the refractive index of ZnSe is about 2.4, when light enters the ZnSe from the air due to the difference in refractive index from air having a refractive index of 1, the interface between air and ZnSe, that is, the incident surface 502 The light is refracted at. This refraction angle follows the following relational expression (Equation 10) according to Snell's law. Here, n ₁ is the refractive index of air, n ₂ is the refractive index of ZnSe, θ ₁ is the incident angle, and θ ₂ is the refractive angle.

In general, the curve of the bent portion of the bony portion in the external auditory canal 204 is bent toward the back of the head by about 56 degrees on average. Accordingly, it is preferable to refract the optical path by about 56 degrees using the optical path changing element 105 so that the optical path of the infrared light emitted from the eardrum 202 passes through the insertion probe 104. That is, it is preferable to set the angle (angle of the slope in FIG. 5) θ between the incident surface 502 and the exit surface 504 so that the angle θ ₃ in FIG. 5 is about 56 degrees.

As can be seen from FIG. 5, the incident angle θ ₁ is equal to the sum of the refraction angles θ ₂ and θ _3, and θ is equal to the refraction angle θ ₂ . From these relationships, calculation using the formula (Equation 10) shows that the angle θ formed by the incident surface 502 and the exit surface 504 may be set to about 24 degrees.

  FIG. 6 is a cross-sectional view showing a state where the optical path changing element 105 is attached to the distal end portion of the insertion probe 104. The optical path changing element 105 is held by a support portion 107 and can be easily mounted by fitting it into the distal end portion of the insertion probe 104.

  According to the biological component concentration measuring apparatus 100 according to the present embodiment, the infrared light emitted from the eardrum 202 is refracted when entering the incident surface 502 of the optical path changing element 105, thereby proceeding straight through the insertion probe 104. The optical path is changed as follows. Therefore, according to the biological component concentration measuring apparatus 100 according to the present embodiment, more infrared light reaches the infrared detector 108 than when the optical path changing element 105 is not provided. The emitted infrared light can be sufficiently measured, and the measurement accuracy of the biological component concentration can be improved.

  Moreover, according to the biological component concentration measuring apparatus 100 according to the present embodiment, the infrared light emitted from the eardrum 202 is selected by blocking the infrared light emitted from other than the eardrum 202 using the liquid crystal shutter 120. Therefore, the influence of the external auditory canal 204 can be removed, and more accurate measurement can be performed. Further, the measurement accuracy can be further improved by correcting the measured signal by the area of the eardrum from which the measured infrared light is emitted.

(Embodiment 2)
Next, a second embodiment of the present invention will be described. In the present embodiment, the shape of the optical path changing element is different from that of the first embodiment. Other configurations and operations of the biological component concentration measuring apparatus are the same as those in the first embodiment, and the description thereof is omitted.

  FIG. 7 is a cross-sectional view of the optical path changing element in the biological component concentration measuring apparatus according to the present embodiment. In FIG. 7, arrows indicate the optical path of infrared light.

  The optical path changing element 700 of the biological component concentration measuring apparatus according to the present embodiment has a plurality of incident surfaces 702. In this case, since the volume is smaller than that of the optical path changing element 105 in the first embodiment, the cost of the biological component concentration measuring apparatus can be reduced.

  The optical path changing element 700 in the present embodiment can be manufactured by processing, for example, ZnSe. If the refractive index of ZnSe is about 2.4, the angle (slope angle) formed by the incident surface 702 and the exit surface 704 may be about 24 degrees.

  FIG. 8 is a cross-sectional view showing a state where the optical path changing element 700 is attached to the distal end portion of the insertion probe 104. The optical path changing element 700 is held by a support portion 706, and can be easily mounted by fitting it into the distal end portion of the insertion probe 104.

  According to the biological component concentration measuring apparatus according to the present embodiment, as in the first embodiment, more infrared light reaches the infrared detector 108 than when the optical path changing element 700 is not provided. Therefore, the infrared light emitted from the eardrum 202 can be sufficiently measured, and the measurement accuracy of the biological component concentration can be improved.

  In the above embodiment, the example in which the optical path changing element is held by the support portion which is a separate member has been shown. It is good also as one member. In this way, the number of parts is reduced, which is useful for mass production.

(Embodiment 3)
Next, a third embodiment of the present invention will be described. The biological component concentration measuring apparatus according to the present embodiment is different from the first and second embodiments in that the optical path changing element has a reflecting surface and does not include a support portion. Other configurations and operations of the biological component concentration measuring apparatus are the same as those in the first embodiment, and the description thereof is omitted.

  The optical path changing element 800 in the biological component concentration measuring apparatus according to the present embodiment will be described with reference to FIG. FIG. 9A is a cross-sectional view of the optical path changing element 800, and FIG. 9B is a right side view. In FIG. 9, the arrow indicates the optical path of infrared light.

  The optical path changing element 800 has a disk shape having a concave portion 808 on one surface, and five protrusions having a triangular cross section are formed in parallel to each other on the other surface. One surface of each projection functions as an incident surface 802, the other surface functions as a reflective surface 806, and the bottom surface of the recess 808 functions as an output surface 804, and infrared light emitted from the eardrum 202 is incident from the incident surface 802, The light path is reflected by reflection at the reflection surface 806, and the light is emitted from the emission surface 804 toward the insertion probe 104. In order to increase the reflectance of infrared light on the reflecting surface 806, a reflecting mirror is preferably provided on the reflecting surface 806.

  The outer diameter of the optical path conversion element 800 may be smaller than the inner diameter of the human ear canal, and is set to about 3 mm to 8 mm. The width of each protrusion is set to about 10 μm to 3 mm.

  Similarly to the first embodiment, in order to refract the optical path by about 56 degrees using the optical path changing element 800, the apex angle of the triangle in the cross section of the protrusion may be set to 56 degrees. Further, the apex angle of the triangle in the cross section of the protrusion may be optimized for each individual according to the degree of bending of the user's external auditory canal 204.

  The material for the optical path changing element 800 is preferably transparent in the infrared region, and for example, polycarbonate, polypropylene, polyethylene, or the like can be used. Moreover, you may form combining a some material. For example, high-strength polycarbonate may be used for the outer peripheral portion, and polyethylene may be used for the portion through which infrared light passes. The optical path changing element 800 can be manufactured by a known resin molding technique using a mold.

  As a material for the reflecting mirror formed on the reflecting surface 806, any material that reflects infrared light and has no toxicity can be used without particular limitation. For example, the reflecting mirror 806 can be formed by coating an optical path changing element 800 by forming a resin and then coating a material such as gold or aluminum.

  Although FIG. 9 illustrates an example in which five protrusions are formed, the number of protrusions is not particularly limited, and may be one. The cross-sectional shape of the protrusion may be a trapezoidal shape.

  FIG. 10 is a cross-sectional view showing a state where the optical path changing element 800 is attached to the distal end portion of the insertion probe 104. By fitting the recess 808 of the optical path changing element 800 into the distal end portion of the insertion probe 104, the optical path changing element 800 can be easily attached to the distal end portion of the insertion probe 104.

  Next, a method of forming a reflecting mirror on the optical path changing element 800 will be described with reference to FIG. FIG. 11 is a cross-sectional view showing the structure of a vacuum vapor deposition apparatus 900 used when forming a reflecting mirror on the optical path changing element 800.

  The optical path changing element 800 produced by resin formation is placed on a holder 902 provided in the bell jar 901 of the vacuum vapor deposition apparatus 900 so that one side of the protrusion (reflecting surface 806) faces downward, and the inside of the bell jar 901 is vacuumed. The pressure is reduced by the pump 905.

  Next, by irradiating a crucible 903 filled with a metal such as gold or aluminum with an electron beam generated from an electron gun 904, the metal in the crucible 903 is melted and evaporated, and the projection of the optical path changing element 800 is formed. A reflecting mirror is formed on the reflecting surface 806.

  According to the biological component concentration measuring apparatus according to the present embodiment, as in the first embodiment, more infrared light reaches the infrared detector 108 than when the optical path changing element 800 is not provided. Therefore, the infrared light emitted from the eardrum 202 can be sufficiently measured, and the measurement accuracy of the biological component concentration can be improved.

  Further, according to the biological component concentration measuring apparatus according to the present embodiment, the volume is reduced by providing a plurality of reflecting surfaces as compared with the optical path changing element 105 in the first embodiment. Cost can be reduced. In addition, since a resin that is less expensive than ZnSe or diamond and can be easily processed can be used, the biological component concentration measuring apparatus can be further reduced in cost.

(Embodiment 4)
Next, a fourth embodiment of the present invention will be described. The biological component concentration measurement apparatus according to the present embodiment is different from the first embodiment in that the insertion probe has a bent portion and a reflection mirror is provided inside the insertion probe. Other configurations and operations of the biological component concentration measuring apparatus are the same as those in the first embodiment, and the description thereof is omitted.

  The insertion probe 950 and the optical path changing element 970 in the biological component concentration measuring apparatus according to the present embodiment will be described with reference to FIG. FIG. 12 is a cross-sectional view showing a state where the insertion probe 950 is inserted into the ear canal 200 in the biological component concentration measuring apparatus according to the present embodiment. In FIG. 12, the arrow indicates the optical path of infrared light.

  The insertion probe 950 has a bent portion 960, and the bent portion 960 is bent along the external auditory canal 204. A reflecting mirror 990 is provided on the inner surface of the insertion probe 950 and between the bent portion 960 and the opening on the eardrum 202 side. An optical path changing element 970 supported by a support portion 980 is attached to the distal end portion of the insertion probe 950.

  The infrared light emitted from the eardrum 202 is once changed in the optical path by the optical path changing element 970 and incident on the insertion probe 950, and then reflected by the reflecting mirror 990 provided in the insertion probe 950. The optical path is changed, and the light travels straight through the insertion probe 104.

  According to the biological component concentration measuring apparatus according to the present embodiment, as in the first embodiment, more infrared light reaches the infrared detector 108 than when no optical path changing element 970 is provided. Therefore, the infrared light emitted from the eardrum 202 can be sufficiently measured, and the measurement accuracy of the biological component concentration can be improved. Compared with the biological component concentration measuring apparatus according to the first embodiment, the optical path can be changed not only by the optical path changing element 970 but also by the reflecting mirror 990 provided in the insertion probe 950, so that the optical path is changed more greatly. can do. Therefore, it is particularly useful when used for a person whose outer ear canal is greatly bent.

  The present invention is useful for non-invasive measurement of biological component concentration, for example, measuring glucose concentration without collecting blood.

Schematic which shows the structure of the biological component concentration measuring apparatus in one embodiment of this invention. The figure which shows the structure of the same biological component concentration measuring apparatus The perspective view which shows the optical filter wheel in the same biological component density | concentration measuring apparatus The image figure which shows the image when the inside of an ear canal is observed using the living body component concentration measuring device Sectional drawing of the optical path changing element in the same biological component concentration measuring apparatus Sectional drawing which shows the state which mounted | worn the optical path change element at the front-end | tip part of the insertion probe Sectional drawing of the optical path change element in the biological component concentration measuring apparatus which concerns on other embodiment of this invention. Sectional drawing which shows the state which mounted | worn the optical path change element at the front-end | tip part of the insertion probe (A) Sectional drawing of the optical path changing element in the biological component concentration measuring apparatus which concerns on other embodiment of this invention, (b) Right view Sectional drawing which shows the state which mounted | worn the optical path change element at the front-end | tip part of the insertion probe Sectional drawing which shows the structure of the vacuum evaporation machine used when forming a reflective mirror in the same optical path changing element Sectional drawing which shows the state which inserted the insertion probe in the biological component concentration measuring apparatus which concerns on other embodiment of this invention in the ear hole.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Biological component concentration measuring apparatus 101 Power switch 102 Main body 103 Measurement start switch 104,950 Insertion probe 105,700,800,970 Optical path changing element 106 Optical filter wheel 107,706,980 Support part 108 Infrared detector 110 Microcomputer 112 Memory 114 Display 116 Power Supply 118 Chopper 120 Liquid Crystal Shutter 122 First Optical Filter 123 Ring 124 Second Optical Filter 125 Shaft 126 Detection Area 130 Preamplifier 132 Band Filter 134 Synchronous Demodulator 136 Low Pass Filter 138 A / D Converter 140 Light Source 142 First half mirror 144 Second half mirror 146 Condensing lens 148 Image sensor 150 Actuator 152 Lens frame 1 54 Position sensor 156 Timer 158 Buzzer 200 Ear hole 202 Tympanic membrane 204 External auditory canal 502,702,802 Entrance surface 504,704,804 Exit surface 806 Reflection surface 808 Concavity 900 Vacuum vapor deposition machine 901 Belger 902 Holder 903 Crucible 904 Electron gun 905 Vacuum pump 960 Vacuum pump 960 990 Reflector

Claims (5)

An insertion probe for insertion into the ear canal;
An optical path changing element provided at the distal end of the insertion probe and having an incident surface on which infrared light emitted from the eardrum is incident;
A spectroscopic element for dispersing the infrared light for each wavelength;
An infrared detector for detecting the infrared light dispersed by the spectroscopic element;
A biological component concentration calculator that converts the output of the infrared detector into a biological component concentration;
The biological component concentration measuring device, wherein the optical path changing element changes an optical path of the infrared light so that the infrared light passes through the insertion probe. The optical path changing element is
Has a higher refractive index than air,
The biological component concentration measurement apparatus according to claim 1, wherein an optical path of the infrared light is changed so that the infrared light passes through the insertion probe by refracting the infrared light on the incident surface. The biological component concentration measuring apparatus according to claim 2, wherein the optical path changing element has a plurality of incident surfaces. The optical path changing element is
A reflective surface;
The living body according to claim 1, wherein the infrared light incident from the incident surface is reflected by the reflecting surface to change the optical path of the infrared light so that the infrared light passes through the insertion probe. Component concentration measuring device. The insertion probe has a bent portion;
A reflection mirror provided on the inner surface of the insertion probe and provided between the bent portion and the tip portion;
The infrared light that has entered the insertion probe through the optical path changing element is reflected by the reflecting mirror, so that the optical path of the infrared light is changed so that the infrared light passes through the insertion probe. The biological component concentration measuring apparatus according to claim 1, wherein

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