JP2007195653A - Radiation spectral densitometer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radiation spectral densitometer capable of precisely detecting radiation light alone from a measuring object. <P>SOLUTION: This radiation spectral densitometer is provided with an infrared radiation body, an infrared waveguide, a spectrum filter, an infrared detector for detecting infrared light from the infrared radiation body transmitting through the infrared waveguide, a means for calculating the density of an object component inside the infrared radiation body from the output of the infrared detector, and a display retaining means displaying and retaining the density. This radiation spectral densitometer which, after inserting an insertion guide 2 into the auditory meatus, transmits the infrared light from the drum membrane 1 to be radiated by the body temperature by the infrared waveguide 3, diffracts it by the spectrum filter 5, detects it by the infrared detector 6, calculates the glucose concentration inside the drum membrane 1, and displays the blood glucose level, captures and tracks the drum membrane 1 by a solid angle transition mechanism 8. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a radiation spectral densitometer for non-invasively and noninvasively measuring blood component and tissue component concentrations of a human body, and more particularly to a device for measuring radiated light from the eardrum.

  As a device for noninvasive detection of the concentration of an analyte (for example, glucose) in human tissue such as blood, there is one proposed in Patent Document 1, for example. FIG. 10 schematically shows the configuration of a radiation spectral densitometer proposed in Patent Document 1. As shown in FIG. 10, the conventional radiation spectral densitometer includes a plastic cover 62, a reflecting mirror 63, an infrared waveguide 64, an optical valve 65, an infrared filter set 66, a detector 67, an electronic circuit 68, a microcomputer 69 and A display device 60 is included.

  Infrared rays from the human eardrum 61 pass through an infrared waveguide 64 in a reflecting mirror 63 having a plastic cover 62 inserted into the ear canal, and in order to start the measurement of infrared rays, the infrared rays pass according to time. Pass through an optical valve 5 that can be turned on or off. Thereafter, the infrared ray is detected by a detection device 67 having sensitivity to the infrared ray.

  The detection device 67 is provided with an infrared filter set 66, and an infrared spectrum is selected by the infrared filter set 66. The detection device 67 generates an electrical signal indicating the intensity of the received infrared light, and the electronic circuit 68 and the microcomputer 69 determine the correlation between the spectral intensity of the infrared light emitted from the human body and the concentration of the analyte, and the analyte. Calculate the concentration of. The obtained concentration of the analyte is displayed on the display device 60.

  The eardrum of the human body is at the back of the ear canal, but the shape of the ear canal is not simple, and there are first and second curves from the outside. The shape of this curve varies greatly from person to person. The angle of the curve in the horizontal direction is about 90 degrees in the occipital region in the first curve and about 90 degrees in the second curve, indicating the S-curve shape. The vertical direction is upward between the first curve and the second curve, and substantially horizontal after the second curve.

  The tissue that forms the external auditory canal is roughly a cartilage tissue that does not feel pain until the second curve, but after the second curve is a bony tissue, it is a tissue that feels pain strongly. For this reason, it is difficult to insert the second and subsequent curves when using a linear probe. Even when a curved probe created for each individual is used, the probe is always in contact with the person's posture and jaw movement. It is difficult to make the front face face the eardrum.

An ear canal thermometer is widely used to measure the tympanic radiation, but it also measures the radiation from the ear canal near the tympanic membrane. This is because the temperature difference between the eardrum and the ear canal is as small as about 0.1 to 0.2 degrees, and the measurement principle is to measure the radiation of the quasi-blackbody cavity formed from the eardrum and the ear canal near the eardrum. .
JP-T-2001-503999

  However, in the conventional spectroradiometer, the eardrum is very thin with a thickness of 0.1 mm or less, and skin tissue and blood vessels are present in the eardrum, and the blood vessels are near the surface of the eardrum. Similar to the site, the blood vessels are deeper than the tympanic membrane, so the information in the blood cannot be obtained from the emitted light. In other words, unlike the ear hole thermometer, this radiation spectral densitometer needs to detect only the radiation from the eardrum more accurately.

  The present invention has been made to solve the above-described conventional problems, and an object thereof is to provide a radiation spectral densitometer capable of accurately detecting only radiation light from the eardrum.

  A radiation spectral densitometer according to the present invention includes an infrared waveguide, a spectral filter, an infrared detector for detecting infrared rays from an infrared radiator transmitted through the infrared waveguide, and an output of the infrared detector. A means for calculating the concentration of the target component in the infrared radiator, and a display storage means for displaying and storing the concentration, wherein the infrared waveguide has a function of determining and recognizing the infrared radiator. It has the structure.

  With this configuration, it is possible to always measure the infrared rays of the infrared radiator regardless of external fluctuations.

  The radiation spectral densitometer of the present invention has a configuration in which the function of determining and recognizing the infrared radiator is adjustment with a viewing angle with the end of the infrared waveguide on the infrared radiator side as a fulcrum. is doing.

  With this configuration, it is possible to always measure the infrared rays of the infrared radiator while keeping the distance from the infrared radiator constant.

  The radiation spectral densitometer of the present invention has a configuration in which a part or total integral of the infrared radiation spectrum of the infrared radiator is used for capturing and tracking the infrared radiator.

  With this configuration, the infrared radiator can be accurately tracked with the highest signal amount as a detection signal.

  In the radiation spectral densitometer of the present invention, an infrared chopper having at least two openings is disposed between the infrared waveguide and the infrared detector, and the spectral filter is disposed in one opening of the infrared chopper. It has an arrangement.

  With this configuration, it is possible to obtain a signal for capturing and tracking an infrared emitter and a spectral signal for calculating the target component concentration with one infrared detector.

  The present invention relates to an infrared waveguide, a spectral filter, an infrared detector for detecting infrared rays from an infrared radiator that has passed through the infrared waveguide, and an output from the infrared detector in the infrared radiator. A means for calculating the concentration of the target component; and a display storage means for displaying and storing the concentration, and at least the infrared waveguide is provided with a function of capturing and tracking the infrared radiator, thereby providing external fluctuations. Therefore, it is possible to provide a radiation spectral densitometer having an effect that the infrared rays of the infrared radiator can always be measured.

  First, the operation principle of the present invention will be described.

  In general, an object of a certain temperature exchanges heat with the external environment (heat transfer), and there are three forms. The first is conduction, which is a phenomenon in which heat is transferred by exchanging momentum due to contact of particles in an object, which is called heat conduction. The second is convection, which is a phenomenon in which heat is transferred between the solid surface and the fluid by the movement of fluid particles, and is called convection heat transfer. The third is radiation, which means that all objects radiate or absorb energy from electromagnetic waves according to temperature, and the heat exchange phenomenon due to that energy is called thermal radiation or thermal radiation. . These heat transfer phenomena rarely occur independently, and in reality, two or three phenomena occur simultaneously.

  The living body also has the same heat transfer phenomenon as described above. For example, the human body temperature (body temperature) has a deep body temperature that is not changed by the environmental temperature, and is carried to various parts of the body by blood circulation. As the skin temperature increases, the blood flow of the skin increases as the skin blood vessels expand, and the amount of heat (heat dissipation) released to the outside increases. Conversely, if the skin blood vessels contract, the heat dissipation becomes smaller. The skin temperature rises when the skin blood vessels expand and the blood flow increases, and decreases when it contracts. In other words, heat is exchanged with the external environment on the skin surface, which is the boundary with the outside world, and is balanced with changes in the external environment by heat conduction, convection heat transfer, and heat radiation.

  Thermal radiation is radiation or absorption of energy by electromagnetic waves, but since the deep temperature of the human body is around 37 degrees, electromagnetic waves in the infrared region over a wavelength range of 8-12 μm correspond. In general, the average emissivity, which is the radiation (absorption) ability of the skin, is as high as about 0.98 when the ideal black body, which is the theoretical limit, is 1, and is a good radiation (absorption) body.

  On the other hand, an object has radiation (absorption) characteristics for electromagnetic waves according to the type and composition ratio (concentration) of its constituent substances. The atomic spectrum and molecular spectrum correspond to this. The infrared region is divided into a near infrared region up to a wavelength of 2.5 μm and a mid infrared region from 2.5 μm to 10 μm. The mid-infrared region corresponds to the fundamental molecular vibration level unique to characteristic chemical bonds, and has a sharp and strong absorption characteristic compared to the complex and non-sharp complex and weak absorption characteristic of the near-infrared region. Therefore, the target molecule is highly recognizable.

For example, blood sugar (glucose), which is a blood component, is a molecule represented by C ₆ H ₁₂ O ₆ , and the level of stretching vibration and bending vibration of CC, C—H, and OH in the mid-infrared region. In particular, in the wavelength range of 8 to 12 μm, which is the wavelength band of radiation emitted from the human body, there are levels of C-H variable vibration and C-O-H variable vibration. The radiation spectrum is modulated by the presence and concentration of glucose in the blood and tissue interstitial fluid. By observing the radiation spectrum due to the body temperature (skin temperature) of the human body, blood components can be measured noninvasively. I can do it.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected to the same or an equivalent part, and the overlapping description may be abbreviate | omitted.

  FIG. 1 is a schematic diagram showing a configuration of a preferred embodiment of a radiation spectral densitometer of the present invention. In the present embodiment, a case will be described in which a tympanic membrane, which is a part of a living body, is used as an infrared radiator, and a blood glucose level is measured as the concentration of a target component to be analyzed.

  As shown in FIG. 1, the radiation spectral densitometer 20 of the present embodiment emits infrared rays due to the body temperature of the insertion guide 2 a and the external cover 2 b and the eardrum 1 for insertion into the ear canal of the ear with a part of the body cover 2. Infrared waveguide 3 for transmitting and an infrared chopper 4 including a rotating plate 4a that can be rotated by a motor 4b, a single infrared sensor 6, an infrared waveguide 3, an infrared chopper 4, and an infrared sensor sensitive to infrared rays 6 and a solid angle changing mechanism 8 having a mechanism for changing the solid angle relationship between these and the eardrum 1. Then, the infrared waveguide 3, the infrared chopper 4, and the infrared ray are arranged so that the normal direction of the main surface of the rotating plate 4 a substantially coincides with the length direction of the infrared waveguide 3 and the light beam direction from the infrared sensor 6. The positional relationship with the sensor 6 is set.

  Here, FIG. 2 is a front view of the infrared chopper 4 seen from the normal direction of the main surface of the rotating plate 4a in FIG. 1, and FIG. 3 is a diagram showing a cross section taken along line AA in FIG. As shown in FIG. 1 and FIG. 2, the rotating plate 4a of the infrared chopper 4 is provided with four openings 5. In these openings 5, spectral filters 5a, 5b and 5c have spectral characteristics. There is no filter 5d.

  The radiation spectrodensitometer 20 includes an electronic circuit 7 for driving and controlling the infrared sensor 6, the infrared chopper 4 and the solid angle changing mechanism 8, and further amplifying the output signal of the infrared sensor 6. A signal processing device (not shown) for converting the output signal of the infrared sensor 6 into the concentration of the target component, and a display storage means (not shown) for displaying the result of the signal processing device to the user and storing it together with the measurement date and time, etc. including.

  The operation method of the radiation spectral densitometer of the present embodiment having the above configuration will be described below.

  First, the eardrum 1 is an infrared radiator that emits infrared light at that temperature. There is a physical fact that an object other than an absolute temperature of 0 Kelvin emits electromagnetic waves, and the relationship between the amount of radiation, absolute temperature, and wavelength is known as Planck's law. In this Frank's law, the radiation amount of an actual object changes based on the emissivity ε (0 <ε ≦ 1), which is a coefficient based on an ideal black body, but the emissivity ε of a human skin is It has a high emissivity of about 0.98.

  In addition, the change of the wavelength-dependent radiation spectrum with respect to the ideal black body can be expressed using the monochromatic emissivity εi that indicates the emissivity ε for each wavelength. The radiation spectrum in the eardrum 1 varies depending on the components contained in the blood in the eardrum 1 and the tissue components of the eardrum 1, and is directly correlated with the component concentration.

  Here, since the temperature of the eardrum 1 reflects the temperature of the hypothalamus, which controls the body temperature of the brain, it can be said that the deep body temperature, which is the highest temperature in the human body, is exposed outside the body. In addition, the infrared radiation intensity of the eardrum 1 increases as the temperature rises, and is also the part that exhibits the strongest infrared radiation intensity in the human body. Furthermore, the eardrum 1 is very thin with a thickness of about 0.1 mm, and includes a skin layer, a proper layer and a mucous membrane layer in this thickness direction, and also has blood vessels, so it is the most compact compared to other places. This is a place where blood vessels and tissues including blood are formed.

  At least a radiation spectrum having information on the concentration of the target component (glucose) in the blood, that is, information on the blood glucose level, is emitted as infrared rays from the eardrum 1 due to body temperature. The radiation of an ideal black body in the normal body temperature range has a maximum intensity distribution at a wavelength of 8 μm to 11 μm. The blood glucose level is the glucose concentration in the blood. Wavelengths that can identify glucose include 8.00 μm, 9.29 μm, 9.55 μm, 9.75 μm, 9.89 μm, and 10.98 μm. Is available.

  Infrared rays from the eardrum 1 are inserted into the eardrum 1 side of the infrared waveguide 3 inserted to the vicinity of the second curve in a tissue part that does not feel pain strongly in the external auditory canal (not shown) with the insertion guide 2a. The light is incident directly from the inside and repeatedly reflected inside or propagates in the infrared waveguide 3 to reach the other end 3b. As a material constituting the insertion guide 2, for example, a thermoplastic resin such as polyacrylic acid, polystyrene, polyester, polyvinyl chloride, polycarbonate and polypropylene can be used.

  As a material constituting the infrared waveguide 3, a metal having a low emissivity ε such as aluminum, copper, and stainless steel can be used. In this case, a coating made of, for example, gold, silver, or copper having a lower emissivity ε may be provided on at least the inner surface of the infrared waveguide 3 by, for example, vapor deposition, sputtering, or plating.

  The infrared waveguide 3 can be made of a material other than these metals, for example, a thermoplastic resin such as polyacrylic acid, polystyrene, polyester, polyvinyl chloride, polycarbonate and polypropylene. In this case, it is preferable to provide a coating made of, for example, gold, silver, or copper having a lower emissivity ε, for example, by vapor deposition, sputtering, plating, or the like on at least the inner surface of the infrared waveguide 3.

  Infrared rays radiated from the eardrum 1 and passed through the infrared waveguide 3 are transmitted through the spectral filters 5a, 5b, 5c or the filter 5d installed in the opening 5 of the infrared chopper 4, and the radiation spectrum of a specific wavelength of the infrared rays , The emission spectra of all wavelengths are respectively incident on the infrared sensor 6 and converted into electrical signals proportional to the intensity of the incident radiation spectrum.

  Here, the infrared chopper 4, the spectral filters 5a, 5b, 5c and the filter 5d will be described in more detail with reference to FIGS. As shown in FIGS. 2 and 3, the infrared chopper 4 has a rotating plate 4a and rotating means 4b such as a motor, and the rotating plate 4a can be rotated in the direction of arrow Y by the rotating means 4b. .

  Four openings 5 are provided at equiangular intervals on a concentric circle from the center of the rotating plate 4a, and spectral filters 5a, 5b, 5c and a filter 5d are disposed in these openings 5.

  The infrared chopper 4 has an opening 5 of the rotating plate 4a in such a positional relationship that the infrared waveguide 3 and the infrared sensor 6 can be optically connected. That is, when the opening 5 reaches the position shown in FIG. 1 due to the rotation of the rotating plate 4a, it is indicated by a line P from the infrared sensor 6 through the infrared waveguide 3 to the eardrum 1 through the opening 5. Light can pass through.

  Here, as a material constituting the rotating plate 4a, a metal having a low emissivity ε, such as aluminum, copper, and stainless steel, can be used. In this case, a film made of, for example, gold, silver, or copper having a lower emissivity ε may be provided on at least the surface of the rotating plate 4a by, for example, vapor deposition, sputtering, or plating.

  The rotating plate 4a can be made of a material other than these metals, for example, a thermoplastic resin such as polyacrylic acid, polystyrene, polyester, polyvinyl chloride, polycarbonate, and polypropylene. In this case, it is preferable to provide a coating made of gold, silver, copper, or the like having a lower emissivity ε, for example, by vapor deposition, sputtering, plating, or the like on at least the surface of the rotating plate 4a.

  Further, as the rotating means 4b, for example, a motor such as a DC motor, an AC motor, a stepping motor, a servo motor, and a voice coil motor can be used. In this embodiment, the rotating plate 4a is circular and rotates. However, the rotating plate 4a may be semicircular or fan-shaped, and may be repeatedly moved.

  The rotational speed of the rotating plate 4a depends on the specifications of the infrared sensor 6, but the rotating plate 4a is preferably rotated at, for example, several Hz to several tens Hz. This is because the sensitivity of a thermopile or pyroelectric sensor suitably used as the infrared sensor 6 has frequency dependence, and particularly has high sensitivity at several Hz to several tens Hz, and can be detected with high accuracy. .

  Various spectral filters can be used as the spectral filters 5a, 5b, and 5c. For example, a narrowband filter manufactured by JDS Uniphase of the United States or Spectrogen of Sweden can be preferably used. This preferable narrow band filter is obtained by laminating a plurality of layers having different refractive indexes by vapor deposition or sputtering on a substrate transparent to a spectral wavelength composed of, for example, Si, Ge, or ZnSe. Is.

  In the present embodiment, the spectral filters 5a, 5b, and 5c are selected so as to be able to separate wavelengths capable of identifying glucose, and the filter 5d is made of a single material that transmits all infrared rays. A substrate is used. As such substrates, silicon, germanium, barium fluoride, thallium bromoiodide, thallium bromochloride, sodium chloride, potassium bromide, potassium chloride, cesium iodide, zinc selenide, and zinc sulfide can be used. Further, the opening 5 may be used as it is without providing the filter 5d.

  Various infrared sensors 6 can be used. For example, a thermopile and a pyroelectric sensor having sensitivity to infrared rays can be used. As a commercially available product, for example, a product of Nippon Ceramic Co., Ltd. or US PerkinElmer can be suitably used. In the present embodiment, a thermopile is used.

  Here, FIG. 9 shows an example of an output pattern obtained from the infrared sensor 6 when the radiation spectral densitometer 20 of the present embodiment having the configuration shown in FIG. 1 is operated. In FIG. 9, the horizontal axis represents time (unit is arbitrary), and the vertical axis is the intensity (unit is arbitrary) of the output electric signal of the infrared sensor 6. The rotational movement of the infrared chopper 4 is controlled by an electronic circuit 7, and the infrared rays from the infrared waveguide 3 are transmitted from the infrared sensor 6 and the infrared waveguide by the spectral filters 5a, 5b, 5c and the filter 5d at a certain time interval. 3 is incident on the infrared sensor 6 only at the moment when it is optically connected to 3 and outputs an electrical signal proportional to the incident intensity.

  In addition, since an electrical signal is periodically output by the rotational movement of the rotating plate 4a of the infrared chopper 4, it is preferable to obtain a waveform indicating an average value of a plurality of electrical signals using the electronic circuit 7. The peak A in FIG. 4 corresponds to the average waveform of the infrared sensor 6 corresponding to the infrared ray that has passed through the filter 5d. Similarly, peak B corresponds to the spectral filter 5a, peak C corresponds to the spectral filter 5b, and peak D corresponds to the spectral filter 5c.

  The signal processing device calculates the glucose concentration, which is a blood glucose level, from the peak value of the electrical output signal of the infrared sensor corresponding to each of the spectral filters 5a, 5b, 5c and the filter 5d obtained as described above. To do.

  First, the peak A indicating the infrared intensity transmitted through the filter 5d has a direct correlation with the temperature of the eardrum 1. Like the ear-type thermometer and the non-contact radiation thermometer, the relationship between the integral value of the radiation spectrum of the ideal black body and the integral value of the radiation spectrum of the eardrum 1 is the relationship shown in the Stefan-Boltzmann law. Therefore, the temperature of the eardrum 1 can be calculated from the peak A.

  In addition, the radiation spectrum intensity of an ideal black body is given by Planck's law. From Kirchhoff's law showing the relationship between the absorptance and emissivity, the absorptance increases as the glucose concentration increases, and at the same time the monochromatic emissivity εi Will also be higher. That is, the peaks B and C, which are infrared intensities transmitted through the spectral filters 5a, 5b and 5c, which are narrow-band filters in a wavelength band capable of recognizing glucose, and the radiation of the ideal black body at the temperature of the eardrum 1 By calculating the monochromatic emissivity εi, which is the ratio of the spectral intensity, the glucose concentration, which is a blood glucose level, can be obtained.

  Here, the monochromatic emissivity εi is calculated from each of the three spectral filters. The average value of the emissivity εi is the glucose concentration, and the ideal black body at the total intensity of the three peak values and the wavelengths of the three spectral filters. It is also possible to calculate the glucose concentration from the combined monochromatic emissivity with the total emission spectrum intensity.

  In general, the bandwidth of a narrow-band filter, which is a spectral filter, is about ± 1% of the center wavelength at the half-value width of the transmittance. For example, when the center wavelength is 10 μm, the half width is ± 0.1 μm. In other words, in the case of a spectral filter, the infrared radiation spectrum other than the wavelength at which glucose can be recognized is transmitted, which reduces the recognition accuracy. Therefore, it is beneficial to install a plurality of spectral filters as in this embodiment to improve recognition accuracy.

  Alternatively, in order to correct the degree of influence of components other than glucose, such as albumin, which is also a blood component, entering the bandwidth of a narrow band filter that is a spectral filter capable of recognizing glucose, at least one of the three spectral filters. It is possible to obtain more than one sheet by using a spectral filter that can recognize the component concentration.

  Here, four openings 5 are provided in the infrared chopper 4, one is used for measuring the temperature of the eardrum 1, and the remaining three are provided with a spectral filter capable of recognizing glucose. In addition, one or more spectral filters capable of recognizing the target component are sufficient.

  The sensitivity of the thermopile used for the infrared sensor 6 varies depending on the temperature of the thermopile, and the output electrical signal for the incident infrared intensity varies. Therefore, when using a thermopile, although not shown, it is also useful to detect the temperature of the thermopile by installing a thermistor, resistance temperature detector, or thermocouple, and thereby correct the thermopile sensitivity. The same applies when using a pyroelectric sensor. However, in the case of a pyroelectric sensor, the electrical signal is output only at the moment when the incident infrared intensity changes.

  That is, when the thermopile is used as the infrared sensor 6, the infrared ray from the rotating plate 4a is detected when the rotating plate 4a of the infrared chopper 4 faces the thermopile. As described above, since at least the surface of the rotating plate 4a is made of a low emissivity material, it hardly emits infrared rays, but outputs an electrical signal corresponding to the rotating plate 4a.

  On the other hand, when the pyroelectric sensor is used as the infrared sensor 6, the infrared ray from the rotating plate 4a is not detected even if the rotating plate 4a of the infrared chopper 4 faces the pyroelectric sensor. However, when the pyroelectric sensor changes from the time point facing the rotating plate 4a to the time point facing the spectral filter (that is, when the pyroelectric sensor faces the boundary between the rotating plate 4a and the spectral filter) , When the pyroelectric sensor changes from the time when it faces the spectral filter to the time when it faces the rotating plate 4a (that is, when the pyroelectric sensor faces the boundary between the spectral filter and the rotating plate 4a), An electrical signal is output to

  The above is a description of the case where the radiant infrared of the eardrum 1 is accurately measured. However, as described above, the radiant infrared from the ear canal other than the eardrum 1 depends on individual differences in the shape of the ear canal and the movement and posture of the person. The operation of capturing and tracking the eardrum 1 by changing the solid angle so as not to enter the infrared waveguide 3 will be described.

  FIG. 4 is a schematic configuration diagram illustrating the solid angle changing mechanism 8 in FIG. 1 in detail. The infrared waveguide 3, the infrared chopper 4, and the infrared sensor 6 are mechanically connected to each other. Moving shaft 9 on the back, spring 11a and wire 12a connected to moving shaft 9, block 10a on external cover 2b connected to spring 11a, motor 13a on external cover 2b connected to wire 12a, infrared waveguide 3 Connected to the end of the insertion guide 2a and partially in contact with the end of the insertion guide 2a. The bibot sphere 14 serves as a fulcrum when the solid angle changing mechanism 8 moves, and changes the solid angle of the optical axis formed by the infrared waveguide 3, the infrared chopper 4, and the infrared sensor 6.

  5 is a schematic diagram showing the solid angle changing mechanism 8 in detail, as viewed from the direction of the arrow indicated by A in FIG. 4. The block 10a, spring 11a, wire 12a, and motor 13a in FIG. The block 10b, the spring 11b, the wire 12b, and the motor 13b in FIG. 5 are the mechanisms in the front-rear direction in FIG. As can be seen from FIG. 5, the present radiation spectrometer 20 is configured with a mechanism that can move in a biaxial plane in which the movement axis 9 is orthogonal.

  The eardrum 1 and other ear canals are distinguished by their temperature. As is generally known, the temperature is the highest in the eardrum 1 and lower in the ear canal skin, and there is a difference of approximately 0.2 to 0.3 degrees. That is, the eardrum 1 is observed in the maximum case by measuring the temperature. Therefore, in the present embodiment, the value of the peak A in FIG. 9 is transmitted through the filter 5d having no spectral characteristic in the opening 5 of the infrared chopper 4 or the opening 5 alone, and detected and output by the infrared sensor 6. Make adjustments to maximize.

  The adjustment uses the solid angle change mechanism shown in Figs. The infrared waveguide 3, the infrared chopper 4, and the infrared sensor 6 are mechanically connected by an integral part 15. The change of the solid angle is realized by the biaxial movement of the solid angle change mechanism with the bibot sphere 14 as a fulcrum.

  Springs 11a and 11b are connected to the respective moving shafts 9 on the back surface of the integral part 15, and the springs are connected to blocks 10a and 10b fixed to the outer cover 2b. The springs 11a and 11b are in an extended state and a restoring force is applied, and a force in the direction of each block 10a and 10b is always applied.

  By adjusting the lengths of the wires 12a and 12b connected to the moving shaft 9 with this force by the motors 13a and 13b connected to the wires, the lengths of the springs 10a and 10b are changed. Nine nine-dimensional positions are possible.

  The movement of the integral portion 15 due to the change of the position of the moving shaft 9 changes the solid angle of the infrared waveguide 3 with the bibot sphere 14 as a fulcrum, and the viewing direction of the radiation spectrodensitometer 20 can be changed. Tracking is possible. At this time, it goes without saying that the optical axes of the infrared waveguide, the infrared chopper, and the infrared sensor are preserved.

  Here, the integrated portion 15 is made of a material having sufficient mechanical strength, and various metals, resins, and polymer materials can be used. The moving shaft 9 and the blocks 10a and 10b can be made of a material having the same function as that of the integrated portion 15. The springs 11a and 11b can be made of generally used hard steel wire, piano wire, silliman, kurosiri, stainless steel, brass wire, or phosphor bronze. The wires 12a and 12b can be made of the same material as the springs 11a and 11b. As the motors 13a and 13b, for example, motors such as a DC motor, an AC motor, a stepping motor, a servo motor, and a voice coil motor can be used.

  The operation of solid angle adjustment is described in detail below. 7 is a diagram showing a two-dimensional solid angle adjustment range, and FIG. 8 is a flowchart of solid angle adjustment. The amount of signal transmitted through the filter 5d having no spectral characteristics of the infrared chopper 4 and detected and output by the infrared sensor 6 is the temperature of the target beyond the visual field of the infrared waveguide 3, and this temperature is within the ear canal. It judges whether it is the temperature of the eardrum 1 which is the maximum temperature, and performs adjustment.

  After the radiation spectral densitometer 20 is inserted into the ear canal, each of the basic points indicated by the black dots in FIG. 7 is measured to determine the basic point indicating the maximum temperature. In FIG. 7, 5 × 5 = 25 points are set within the possible range, but can be changed as appropriate (flow 1 in FIG. 8).

  Next, the area around the basic point is measured. In Fig. 7, it is a sub-region surrounded by a solid line. Within this sub-region, at least 3 × 3 = 9 or more points are set in the same manner as the previous basic points, and the concentration is measured at the point showing the maximum value (flow 2 and flow 3 in FIG. 8). ).

  When measuring the next concentration after a certain period of time, first measure the temperature at the first concentration measurement point. Compare this value with the value from the previous measurement, and if it is within a certain range (for example, within 0.1 ° C in terms of temperature), perform the second concentration measurement. If the value is different from the previous value, return to Flow 1 or Flow 2 in Fig. 8 according to the amount, correct the position, and then perform the second concentration measurement. For example, if the temperature is converted from 0.1 ° C. to 0.2 ° C., the flow goes to flow 2 in FIG. Thereafter, the above procedure is repeated and the third and subsequent concentrations are measured.

  In the above, the position acquisition and density measurement of the eardrum were always performed in pairs, but the next density measurement can be quickly performed by appropriately performing the position acquisition between the density measurements.

  Fig. 6 shows a part of the solid angle adjustment mechanism shown in Figs. 4 and 5. In FIG. 6, the moving shaft 9 is in contact with a bowl-shaped moving guide 16 fixed to the outer cover 2b. The tip of the moving shaft 9 has a substantially spherical shape with a corner cut off, and the moving guide 16 is made of various metals, resins, ceramics, or the like, and preferably has high wear resistance. Further, there are oils such as grease between the moving shaft 9 and the moving guide 16 and play the role of reducing the frictional resistance.

  As a result, the movement of the moving shaft 9 is along the movement guide 16, and a more smooth and stable solid angle adjustment is possible.

  In the radiation spectral densitometer 20 of the present embodiment, at least the insertion guide 2, the infrared waveguide 3, the infrared chopper 4, the spectral filter 5, the infrared sensor 6, the electronic circuit 7, and the solid angle changing mechanism 8 are It is desirable to be stored in one package. There is a physical separation between the electronic circuit 7 and the signal processing means (not shown) or between the signal processing means and the display storage means (not shown). The device to be inserted into the device can be made smaller and easier to insert, and the display contents can be surely recognized by the user.

  According to the radiation spectral densitometer 20 according to the embodiment of the present invention, a function of capturing and tracking the eardrum 1 is provided, and a solid angle change in the detection direction with the end of the infrared waveguide 3 as a fulcrum is performed. The eardrum 1 is recognized using the total infrared intensity incident on the infrared waveguide 3 as an index, and a plurality of apertures are formed on the infrared chopper 4 so that the spectral intensity measurement and the total infrared intensity can be detected by one infrared sensor 6. By arranging the spectral filter for measuring the spectral intensity and the filter or aperture for measuring the total infrared intensity, the infrared radiation of the infrared radiator can be always measured regardless of external fluctuations. By keeping the distance from the infrared radiator constant, the infrared radiation of the infrared radiator can always be measured without causing external influences (especially pain or damage to the human body). Inspection It can be tracked with the highest signal amount as a signal, it is possible to obtain a signal for acquisition and tracking of the infrared radiator with a compact structure, a spectroscopic signal for calculating the target component concentration.

  In the above embodiment, the case of the human eardrum has been described as the infrared radiator, but the radiation spectral densitometer of the present invention can also be used to analyze infrared radiators such as other biological parts. Is possible. Further, in the above embodiment, the case where the blood glucose level (glucose concentration) is obtained using glucose as the target component has been described. However, if the radiation spectral densitometer of the present invention is used, other blood components and tissue components are similarly used. It is possible to measure.

  As described above, a radiation spectral densitometer according to the present invention includes an infrared waveguide, a spectral filter, an infrared detector for detecting infrared rays from an infrared radiator transmitted through the infrared waveguide, Means for calculating the concentration of the target component in the infrared emitter from the output of the infrared detector, and display storage means for displaying and storing the concentration, wherein at least the infrared waveguide is capable of capturing the infrared emitter; By providing a tracking function, it is possible to always measure the infrared rays of infrared emitters regardless of external fluctuations, and to measure the blood component and tissue component concentration of the human body noninvasively and noninvasively. This method is useful.

The schematic diagram which shows the structure of the radiation spectral densitometer in embodiment of this invention Front view of the infrared chopper in FIG. A-A 'line sectional view of the infrared chopper in FIG. Schematic diagram showing the configuration of a radiation spectral densitometer describing the solid angle change mechanism in FIG. 1 in detail. FIG. 4 is a schematic diagram showing the configuration of a radiation spectrodensitometer describing in detail the solid angle changing mechanism as seen from the direction of arrow A. FIG. 5 is a schematic diagram showing a configuration of a radiation spectrodensitometer in which the solid angle changing mechanism in which a part of FIG. 5 is changed is described in detail. The figure for demonstrating the solid angle adjustment procedure Flow chart of solid angle adjustment procedure The figure which shows an example of the output pattern obtained from an infrared sensor when the radiation spectral densitometer of embodiment of this invention which has the structure shown in FIG. 1 is operated. The figure which shows typically the composition of the conventional radiation spectral densitometer

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tympanic membrane 2a Insertion guide 2b External cover 3 Infrared waveguide 4 Infrared chopper 4a Rotating plate 4b Rotating means 5 Aperture 5a, 5b, 5c Spectral filter 5d Filter 6 Infrared sensor 7 Electronic circuit 8 Solid angle change mechanism 9 Moving shaft 10a, 10b Block 11a, 11b Spring 12a, 12b Wire 13a, 13b Motor 14 Vivot sphere 15 Integral part 16 Movement guide 20 Emission spectrophotometer 60 Display device 61 Target object 62 Plastic cover 63 Reflector 64 Infrared waveguide 65 Optical valve 66 Infrared filter Set 67 Detector 68 Electronic circuit 69 Microcomputer

Claims (5)

An infrared emitter, an infrared waveguide, a spectral filter, an infrared detector for detecting infrared rays from the infrared emitter that has passed through the infrared waveguide, and an output of the infrared detector from the infrared emitter Means for calculating the concentration of the target component, and display storage means for displaying and storing the concentration,
A radiation spectral densitometer, wherein the infrared waveguide performs determination and recognition of the infrared radiator. 2. The radiation spectroscopy according to claim 1, wherein the function of determining and recognizing the infrared radiator is an adjustment with a viewing angle having an end portion on the infrared radiator side of the infrared waveguide as a fulcrum. Densitometer. The radiation spectral densitometer according to claim 1 or 2, wherein a part or total integral of a radiation infrared spectrum of the infrared radiator is used for capturing and tracking the infrared radiator. An infrared chopper having at least two openings is disposed between the infrared waveguide and the infrared detector;
4. The radiation spectral densitometer according to claim 1, wherein the spectral filter is disposed in one opening of the infrared chopper. 5. The radiation spectral densitometer according to claim 4, wherein the infrared radiator is a tympanic membrane of a living body, and the target component is a blood component.

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