JP2009178482A - Biological information measuring apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a biological information measuring apparatus capable of noninvasively and highly accurately measuring biological information using reflected light from an eardrum. <P>SOLUTION: The biological information measuring apparatus comprises: an infrared light source for emitting infrared light to be irradiated into an earhole; a light guiding part for guiding the infrared light into the earhole; a visual field recognition means for recognizing an area capturing the eardrum of the visual field of the light guiding part; a shutter arranged at a position crossing the optical path of the infrared light, for controlling the area where the infrared light passes through; an infrared light detector for detecting the reflected light of the infrared light reflected inside the earhole; and a biological information operation part for calculating the biological information using the output of the infrared light detector due to the reflected light reflected on the eardrum among the reflected light beams. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a biological information measuring apparatus that non-invasively measures biological information, for example, the concentration of biological components such as glucose concentration, without performing blood collection or the like.

Conventionally, as a biological information measuring device that measures biological information non-invasively, a non-invasive blood glucose meter that irradiates the eardrum with infrared light, measures the infrared reflected light from the eardrum, and calculates the glucose concentration has been proposed. (For example, refer to Patent Document 1). Patent Document 1 includes a mirror that is large enough to fit in the ear canal, and inserts the mirror into the ear canal, irradiates infrared light and heat rays through the mirror, and detects light reflected on the eardrum. An apparatus for calculating the glucose concentration from the detection result is disclosed.
Japanese National Patent Publication No. 5-506171

  However, since the external auditory canal varies in degree from person to person and the size of the eardrum also varies from person to person, the visual field seen through the mirror or probe when the mirror or probe is inserted into the ear canal includes not only the eardrum but also the ear canal. For this reason, in the apparatus described in Patent Document 1, not only the eardrum but also the ear canal is irradiated with infrared light, and reflected light reflected on the eardrum and the ear canal is detected. Since the skin of the ear canal is thicker than the eardrum, the blood supply is performed at a relatively deep position, and the reflected light from the ear canal is less in the content of blood information than the reflected light from the eardrum, The reflected light from the ear canal becomes noise. Therefore, the apparatus described in Patent Document 1 has a problem that the measurement accuracy of biological information is poor.

  An object of the present invention is to provide a living body information measuring device which can perform highly accurate measurement non-invasively by selectively using reflected light reflected from the eardrum in view of conventional problems. .

  In order to solve the above-described conventional problems, the biological information measuring device of the present invention includes an infrared light source that emits infrared light emitted toward the inside of the ear canal, and a light guide unit that guides the infrared light into the ear canal. Visual field recognition means for recognizing a region capturing the eardrum in the visual field of the light guide unit, a shutter disposed at a position crossing the optical path of the infrared light, and controlling a region through which the infrared light passes, Using an infrared light detector that detects reflected light of the infrared light reflected in the ear canal, and out of the reflected light, an output of the infrared light detector resulting from the reflected light reflected by the eardrum A biological information calculation unit for calculating biological information.

  According to the biological information measuring device of the present invention, the influence of the reflected light from the ear canal that becomes noise is suppressed by calculating the biological information using the output of the infrared light detector caused by the reflected light from the eardrum. Therefore, biological information can be measured noninvasively and with high accuracy.

  The biological information measuring device according to the present invention is arranged at a position crossing the optical path of the infrared light and means for recognizing the region capturing the eardrum in the visual field of the light guide that guides the infrared light into the ear canal. And a shutter that controls a region through which external light passes.

  The biological information measuring device of the present invention includes an infrared light source that emits infrared light that is irradiated into the ear canal, a light guide that guides the infrared light into the ear canal, and a field of view of the light guide. Field-of-view recognition means for recognizing a region capturing the eardrum, a shutter that is disposed at a position crossing the optical path of the infrared light, and controls the region through which the infrared light passes, and the infrared light reflected in the ear canal An infrared light detector for detecting reflected light of the light, and a biological information calculation unit for calculating biological information using the output of the infrared light detector resulting from the reflected light reflected on the eardrum among the reflected light Is provided. With this configuration, the biological information is calculated using the output of the infrared light detector resulting from the reflected light from the eardrum, so that the influence of the external auditory canal can be suppressed, and the biological information can be noninvasively and highly accurate. Can be measured.

  In the present invention, the infrared light source can be applied without particular limitation. For example, a silicon carbide light source, a ceramic light source, an infrared LED, an infrared laser, a quantum cascade laser, or the like can be used. The infrared light source may be a continuous light source or a pulsed light source.

  As the light guide unit, any member that can guide infrared light may be used. For example, a hollow tube, an optical fiber that transmits infrared light, or the like may 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.

  As the visual field recognition means, for example, an imaging light source that emits light for illuminating the inside of the ear canal, an image sensor that images the light reflected in the ear canal, and imaging information obtained by the image sensor An imaging information detection unit that detects imaging information of the eardrum can be used. With this configuration, the region of the eardrum can be automatically grasped in the region in the ear canal that is irradiated with the infrared light from the infrared light source.

  Further, as a visual field recognition means, an infrared light sensor array in which infrared light sensors for detecting infrared light emitted from the living tissue in the ear canal are arranged in an array, and the infrared light sensor array A thermal image information detection unit that detects thermal image information of the eardrum from the obtained thermal image information may be used.

  As an imaging 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 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 imaging information obtained by the imaging device is performed, for example, the color of the eardrum and the ear canal Examples include a method for recognizing an eardrum image by using a difference or by using a difference in brightness in an image.

  The infrared light sensor may be any sensor that can detect light having a wavelength in the infrared region. For example, a pyroelectric sensor, a thermopile, a bolometer, an HgCdTe (MCT) detector, or the like can be used.

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

  As a method for the thermal image information detection unit to detect thermal image information of the eardrum from the thermal image information obtained by the infrared light sensor array, the output of each infrared light sensor obtained by the infrared light sensor array is used. For example, there is a method of recognizing a thermal image of the eardrum by using a difference in thermal radiation intensity of infrared light between the eardrum and the ear canal.

  In the present invention, a liquid crystal shutter, a mechanical shutter, or the like can be used as the shutter. As the liquid crystal shutter, for example, it is preferable that a TFT (Thin Film Transistor) is provided, and infrared light in a specific region can be transmitted or shielded by being controlled using the TFT.

  Examples of the mechanical shutter include a rotating plate having a plurality of openings. The rotating plate is disposed at a position where the peripheral portion of the rotating plate crosses the optical path of the infrared light, and the plurality of openings are disposed so as to open different positions on the cross section of the optical path perpendicular to the optical axis of the infrared light. It is preferable that

  In the present invention, any infrared light detector may be used 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 is used. Can do.

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

  In the biological information measuring device of the present invention, it is preferable that the light guide is configured to be inserted into the ear canal. The light guide may further have a function of guiding infrared light reflected in the ear canal.

  In the biological information measuring apparatus of the present invention, it is preferable that the infrared light passing through the shutter is a parallel light flux. If the infrared light that passes through the shutter is a parallel light beam, the infrared light emitted from the light guide part goes straight without spreading in the ear canal, so the area that is irradiated with the infrared light is recognized by the visual field recognition means. The region in the field of view to be matched well. Here, the shutter controls a region through which the infrared light passes so that the infrared light guided by the light guide unit is irradiated to the eardrum based on a recognition result of the visual field recognition unit. More preferably, it is set so as to. In this way, since the infrared light emitted from the light guide is selectively applied to the eardrum, the influence of the reflected light from the ear canal is more reliably removed, and the infrared light resulting from the reflected light from the eardrum Biological information can be calculated using the output of the detector.

  It is preferable that the biological information measuring apparatus of the present invention further includes means for converting a divergent light beam from an infrared light source into a parallel light beam. As means for converting into a parallel light beam, known means can be applied without any particular limitation. For example, a plano-convex lens or a concave mirror can be used.

  A parallel light source such as a laser light source may be used as the infrared light source. In this case, infrared light passing through the shutter can be converted into a parallel light beam without using means for converting the divergent light beam into a parallel light beam.

  Further, when a parallel light source such as a laser light source is used as the infrared light source, a means for converting the light beam into a size corresponding to the diameter of the light guide unit may be provided. As means for converting the size of the light beam, for example, two plano-convex lenses, a beam expander, or the like can be used.

  In addition, the biological information measuring device of the present invention further includes a spectroscopic element that splits infrared light reflected from the eardrum, and the infrared light detector is configured to detect infrared light that is split by the spectroscopic element. May be.

  The biological information measuring device 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 reflected by the eardrum and reflects the other. .

  Here, the spectroscopic element may be disposed between the infrared light 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 light. Examples of the resin transparent to infrared light include polycarbonate, polypropylene, and polystyrene.

  The biological information calculation unit calculates a ratio of the region capturing the eardrum in the visual field of the light guide unit based on information on a region capturing the eardrum recognized by the visual field recognition unit, and the ratio It is preferable to correct the biological information by using. The intensity of the infrared light reflected from the living body depends on the area of the portion where the infrared light is reflected. Therefore, even when the area of the eardrum irradiated with infrared light varies, this correction reduces the variation in the measurement result and enables more accurate measurement.

  The biological information measuring device 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 information 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 information measuring apparatus of the present invention may further include an audio output unit that outputs audio when the visual field recognition means detects information of a region capturing the eardrum. Here, it is preferable that the voice output unit changes the frequency or intensity of the voice according to the size of the area of the eardrum recognized by the visual field recognition unit.

  The biological information measuring device of the present invention includes a storage unit that stores correlation data indicating a correlation between an output signal of an infrared detector and biological information, a display unit that displays biological information converted by the biological information calculation unit, and biological information. You may further provide the power supply which supplies the electric power for a measuring apparatus to operate | move.

  The biological information calculation unit may convert the output signal of the infrared detector into biological information 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 information is, for example, the infrared light obtained by measuring the output signal of the infrared detector for a patient having known biological information (for example, blood glucose level). It can be obtained by analyzing the correlation between the output signal of the detector and the biological information.

  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.

  The biological information measured by the biological information measuring device of the present invention includes the concentration of biological components such as glucose concentration (blood glucose level), hemoglobin concentration, cholesterol concentration, and neutral fat concentration, and the shape of the living body.

  When the infrared light emitted from the infrared light source is reflected by the biological tissue, a part of the infrared light is absorbed by the biological component contained in the biological tissue. The wavelength of infrared light absorbed is specific to the biological component, and the amount of absorption depends on the concentration of the biological component contained in the biological tissue. Therefore, the concentration of the biological component can be quantified by measuring the intensity of infrared light reflected in the living body. For example, glucose shows an infrared absorption spectrum having an absorption peak near 9.6 μm. Therefore, the blood sugar level can be measured by irradiating the living tissue with infrared light in a wavelength band including 9.6 μm and measuring the intensity of the reflected light.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. An example in which the biological information is the concentration of the biological component will be described.

(Embodiment 1)
FIG. 1 is a perspective view showing an appearance of biological information measuring apparatus 100 according to Embodiment 1. FIG.

  The biological information measuring apparatus 100 includes a housing 102 and an ear hole insertion unit 104 provided on a side surface of the housing 102. The ear hole insertion unit 104 includes a light guide unit 105 that guides infrared light. The housing 102 includes 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 information measuring device 100, and a measurement start switch 103 for starting the measurement. Is provided.

  Next, the structure inside the housing of the biological information measuring apparatus 100 will be described with reference to FIGS. FIG. 2 is a diagram showing a configuration of biological information measuring apparatus 100 according to Embodiment 1, and FIG. 3 is a perspective view showing optical filter wheel 106 in biological information measuring apparatus 100 according to Embodiment 1.

  Inside the housing of the biological information measuring apparatus 100, a chopper 118, a liquid crystal shutter 120, an optical filter wheel 106, an infrared light detector 108, a preamplifier 130, a band filter 132, a synchronous demodulator 134, a low pass filter 136, an analog / Digital converter (hereinafter abbreviated as A / D converter) 138, microcomputer 110, memory 112, display 114, power source 116, imaging light source 140, first half mirror 142, second half mirror 144, third Half mirror 145, condenser lens 146, image sensor 148, actuator 150, lens frame 152, position sensor 154, timer 156, buzzer 158, infrared continuous light source 159, and infrared light lens 160.

  As shown in FIG. 2, the infrared light emitted from the infrared continuous light source 159 is converted into a parallel light beam by the infrared light lens 160 and then chopped by the chopper 118. The infrared light chopped by the chopper 118 passes through the liquid crystal shutter 120 and is then reflected by the third half mirror 145 toward the light guide unit 105. The positional relationship among the infrared continuous light source 159, the infrared light lens 160, the chopper 118, the third half mirror 145, and the light guide unit 105 is the length direction of the light guide unit 105 and the red light emitted from the infrared continuous light source 159. It is set so that the light beam direction of external light matches. 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 set in a state in which light is transmitted or blocked in accordance with a voltage applied to each liquid crystal cell. Can be controlled. Here, the liquid crystal shutter 120 corresponds to the shutter in the present invention.

  Here, the imaging light source 140, the condensing lens 146, the imaging element 148, the actuator 150, the lens frame 152, and the position sensor 154 correspond to the visual field recognition means in the present invention, and the microcomputer 110 calculates the imaging information in the present invention. It corresponds to a section, an actuator control section, a light source control section, an imaging information detection section, and a biological information calculation section.

  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 has a function of chopping infrared light emitted from the infrared continuous light source 159 and converted into a parallel light beam by the infrared lens 160, and converting the infrared light into a high-frequency infrared light 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 passes through the liquid crystal shutter 120, is reflected by the third half mirror 145, and is guided into the ear hole 200 by the light guide unit 105. The reflected light of the infrared light reflected by the living tissue in the ear canal 200 is guided into the housing by the light guide unit 105, passes through the first half mirror 142 and the third half mirror 145, and the optical filter wheel 106. To reach.

  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 reflected by the living tissue in the ear canal 200 passes is converted into the first optical filter 122 and the second optical filter 124. Can be switched between. 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 reflected light of the infrared light that has passed through the first optical filter 122 or the second optical filter 124 reaches the infrared light detector 108 that includes the detection region 126. The reflected light of the infrared light reaching the infrared light 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 light 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 with the chopping frequency of the chopper 118 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 110 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 the electric signals corresponding to the respective optical filters are integrated 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) including 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 124 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, for a patient having a known biological component concentration (for example, blood glucose level), infrared light reflected from the eardrum is measured. 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 122. 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 living tissue of the ear canal 200 will be described.

  The imaging light source 140 emits visible light for illuminating the eardrum 202. The visible light emitted from the imaging light source 140 and reflected by the second half mirror 144 is reflected by the first half mirror 142, and then is guided into the ear canal 200 through the light guide unit 105, and the ear hole 200. Illuminates the living tissue.

  As the imaging 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 reflects visible light and transmits infrared light. The material of the first half mirror 142 is preferably a material that does not absorb infrared light but transmits infrared light and reflects visible light. As a material of the first half mirror 142, for example, ZnSe, CaF ₂ , Si, Ge, or the like can be used. Here, the first half mirror 142 corresponds to the light splitting element in the present invention.

  The second half mirror 144 has a function of reflecting part of visible light and transmitting the rest.

  The third half mirror 145 has a function of reflecting part of infrared light and transmitting the rest.

  On the other hand, the visible light reflected by the living tissue of the ear canal 200 and entering the light guide unit 105 is reflected by the first half mirror 142, and part of the visible light passes through the second half mirror 144. Visible light transmitted through the second half mirror 144 is condensed 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 information measuring apparatus 100 detects the distance from the image sensor 148 to the living tissue of the ear hole 200, drives the condensing lens 146 held by the lens frame 152, and correctly forms an optical image on the image sensor 148. A mechanism is provided.

  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 when the distance to the eardrum 202 changes, an optical image of the living tissue of the ear canal 200 can be correctly formed on the image sensor 148.

  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 housing 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 housing 102 side. be able to. 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 to the housing 102 side.

  Next, a method for recognizing the position of the eardrum 202 from the biological tissue image of the ear canal 200 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. 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 ear canal insertion portion 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 pixels in the portion corresponding to the eardrum 202 are brighter than the pixels in the portion corresponding to the ear canal 204, the threshold value is set between the brightness of the pixel in the portion corresponding to the eardrum and the brightness of the pixel in the portion 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.

  When the microcomputer 110 recognizes a pixel imaging the eardrum 202 from all the pixels of 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 thereby control the eardrum 202. The liquid crystal cell corresponding to the position of the pixel that captures the image is set to a state where light is transmitted, and the liquid crystal cell corresponding to the position of the pixel that captures images other than the eardrum 202 is set to a state where the light is blocked.

  By setting the liquid crystal shutter 120 as described above, the infrared light emitted from the infrared continuous light 159 is selectively applied to the eardrum 202, so that the measurement accuracy can be improved. Further, since the liquid crystal shutter 120 is not arranged on the optical path connecting the reflected light from the eardrum 202 and the infrared light detector 108, the reflected light from the eardrum 202 is not blocked by the liquid crystal shutter 120. Therefore, more reflected light from the eardrum 202 can be guided to the infrared light detector 108, so that measurement sensitivity can be improved.

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

  First, when the user presses the power switch 101 of the biological information measuring apparatus 100, the power in the housing 102 is turned on, and the biological information measuring apparatus 100 is in a measurement preparation state.

  Next, the user holds the housing 102 and inserts the ear hole insertion portion 104 into the ear hole 200. The ear canal insertion section 104 is a conical hollow tube whose diameter increases from the distal end portion of the ear canal insertion section 104 toward the connection portion with the housing 102. Therefore, the outer diameter of the ear canal insertion section 104 is the ear hole 200. The ear hole insertion portion 104 is not inserted beyond a position equal to the inner diameter of the ear hole.

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

  Next, the step of recognizing the region 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 captured by the image sensor 148, the insertion direction of the ear canal insertion unit 104 is deviated from the eardrum 202. A message is displayed on the display 114, a buzzer 158 is sounded, or a voice 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 region of the eardrum 202 cannot be recognized is notified, the user may adjust the insertion direction of the ear canal insertion unit 104 by moving the biological information measurement device 100.

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

  As a result of the image recognition, when the microcomputer 110 determines that the region of the eardrum 202 has been recognized in the image captured by the image sensor 148, a message indicating that the region 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 region of the eardrum 202 is recognized, infrared light is automatically emitted from the infrared continuous light source 159, and the microcomputer 110 starts the operation of the chopper 118, thereby reflecting the infrared light from the eardrum 202. Light measurement is started. By notifying the user that the region of the eardrum 202 has been recognized, the user can grasp that the measurement has been started. Therefore, the biological information measuring device 100 may be stopped without moving. Can be recognized.

  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 can be 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 reach the position of the eardrum 202. The corresponding liquid crystal cell is set to a state where infrared light from the infrared continuous light source 159 is transmitted, and the liquid crystal cell corresponding to a position other than the eardrum 202 is set to a state where the infrared light from the infrared continuous light source 159 is blocked. By setting, measurement of reflected light from the eardrum 202 is started.

  Even after the measurement of infrared light is started, the process for recognizing the position of the eardrum 202 in the image captured by the image sensor 148 is continuously performed. If the user removes the ear canal insertion portion 104 from the ear canal 200 or moves the ear canal insertion portion 104 greatly during the measurement, the microcomputer 110 is photographed by the image sensor 148. By determining that there is no image corresponding to the eardrum 202 in the captured image, 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 ear canal insertion section 104 is deviated from the eardrum 202, sounds a buzzer 158, or sounds from a speaker (not shown). To notify the user of an error. Furthermore, the microcomputer 110 automatically stops the measurement by controlling the chopper 118 to block the infrared light irradiated on the eardrum 202. Here, when the ratio of the region of the eardrum 202 in the captured image calculated by the microcomputer 110 is equal to or less than the threshold value, the user may be notified of an error.

  When an error indicating that the region of the eardrum 202 cannot be recognized is notified, the user moves the biological information measuring device 100 to reinsert the ear canal insertion unit 104 into the ear canal 200 or the insertion direction of the ear canal insertion unit 104. After adjusting, 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 infrared continuous light source 159 to block infrared light applied to the eardrum 202. 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 ear canal insertion part 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 signal measured by the infrared light detector 108 can be corrected by the area of the eardrum irradiated with infrared light.

  As described above, according to biological information measuring apparatus 100 according to the present embodiment, infrared light only on eardrum 202 is irradiated by blocking infrared light other than eardrum 202 using liquid crystal shutter 120. Therefore, the influence of the external auditory canal 204 can be removed, and highly accurate measurement can be performed. Further, the measurement accuracy can be further improved by correcting the measured signal by the area irradiated with infrared light.

(Embodiment 2)
Next, a biological information measuring apparatus according to Embodiment 2 of the present invention will be described with reference to the drawings. FIG. 5 is a diagram illustrating a configuration of the biological information measuring apparatus 400 according to the second embodiment.

  Biological information measuring apparatus 400 according to the second embodiment differs from biological information measuring apparatus 100 according to the first embodiment in that rotating plate 302 that is a mechanical shutter is used as a shutter instead of a liquid crystal shutter. Since the configuration other than the shutter is the same as that of the biological information measuring apparatus 100 of the first embodiment, the same reference numerals are given and description thereof is omitted.

  Next, a mechanical shutter provided in the biological information measuring apparatus 400 according to the second embodiment will be described with reference to FIGS. 6 is a front view of the rotating plate 302 seen from the direction of the arrow X in FIG. 5, and FIG. 7 is a diagram showing the arrangement of the rotating plate 302, the infrared continuous light source 159, the infrared light lens 102, and the chopper 118. It is. In FIG. 7, the rotating plate 302 is illustrated as a partial cross-sectional view along the line AA in FIG. 6.

  The biological information measuring apparatus 400 includes a rotating plate 302 that is a mechanical shutter as a shutter. The shaft attached to the rotating plate 302 is configured to rotate in conjunction with the rotation of a motor (not shown) controlled by a signal from the microcomputer 110. The rotating plate 302 is disposed between the chopper 118 and the third half mirror 145, and the normal direction of the main surface of the rotating plate 302 (that is, the direction X of the arrow in FIG. 5) and the parallel light beam by the infrared light lens 160. The positional relationship among the infrared continuous light source 159, the infrared light lens 160, the chopper 118, the rotating plate 302, and the third half mirror 145 is set so that the light beam direction of the infrared light converted into the light beam matches. .

  As shown in FIG. 6, 19 openings 304 are provided in the peripheral portion of the rotating plate 302.

  In FIG. 6, when the rotating plate 302 rotates about the center C by 18 degrees, the infrared light that has passed through the chopper 118 has 20 different irradiation positions 303 on the rotating plate 302 as indicated by a one-dot chain line. Is irradiated.

  The opening 304 is a circle whose diameter is one fifth of the diameter of the irradiated infrared light beam. The 19 openings 304 are respectively provided at 19 irradiation positions 303 out of the 20 irradiation positions 303. The position of each opening 304 at the irradiation position 303 corresponds to a different lattice position of a hexagonal lattice centering on the center D of the irradiation position 303.

  One of the irradiation positions 303 is configured not to have the opening 304. By rotating the rotating plate 302 and fixing the rotating plate 302 so that infrared light is irradiated to the irradiation position 303 having no opening 304, it is possible to prevent infrared light from being irradiated into the ear canal. Therefore, it is possible to prevent deterioration in measurement accuracy due to temperature rise in the ear canal due to infrared light irradiation.

  Due to the rotation of the rotating plate 302, the infrared light that has passed through the openings 304 is irradiated to different positions in the ear canal via the light guide unit 105 corresponding to each of the nineteen openings 304.

  When the microcomputer 110 recognizes a pixel that images the eardrum 202 from all the pixels of the image sensor 148 by the image processing described above, the microcomputer 110 rotates the rotating plate 302 to the position of the pixel that images the eardrum 202. The infrared continuous light source 159 is controlled so that infrared light is emitted from the infrared continuous light source 159 only when the corresponding opening 304 comes to the position shown in FIG.

  Thereby, since the infrared light emitted from the infrared continuous light source 159 is selectively irradiated to the eardrum 202, there is no reflected light from other than the eardrum, and the measurement accuracy can be improved. Further, since the rotating plate 302 is not disposed on the optical path connecting the reflected light from the eardrum 202 and the infrared light detector 108, the reflected light from the eardrum 202 is not blocked by the rotating plate 302. Therefore, more reflected light from the eardrum 202 can be guided to the infrared light detector 108, so that measurement sensitivity can be improved. In addition, since the intensity of the infrared light emitted from the infrared light source is not attenuated by passing through the liquid crystal shutter, more infrared light can be applied to the eardrum 202 per unit area. Measurement sensitivity can be improved.

  As a material constituting the rotating plate 302, for example, a metal having a low emissivity such as aluminum, copper, and stainless steel can be used. In this case, it is preferable to further provide, for example, a coating made of gold, silver, copper or the like having a lower emissivity, for example, by vapor deposition, sputtering, plating, or the like on at least the surface of the rotating plate.

  As the motor, a DC motor, an AC motor, a stepping motor, a servo motor, or the like can be used.

  Next, the operation of biological concentration measuring apparatus 400 in the present embodiment will be described.

  First, when the user presses the power switch 101 of the biological information measuring device 400, the power supply in the housing 102 is turned on, and the biological information measuring device 400 is in a measurement preparation state.

  Next, the user holds the housing 102 and inserts the ear hole insertion portion 104 into the ear hole 200. The ear canal insertion section 104 is a conical hollow tube whose diameter increases from the distal end portion of the ear canal insertion section 104 toward the connection portion with the housing 102. Therefore, the outer diameter of the ear canal insertion section 104 is the ear hole 200. The ear hole insertion portion 104 is not inserted beyond a position equal to the inner diameter of the ear hole.

  Next, when the user presses the measurement start switch 103 of the biological information measuring device 400 while holding the biological information measuring device 400 at a position where the outer diameter of the ear hole insertion portion 104 is equal to the inner diameter of the ear hole 200, the housing The imaging 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 captured by the image sensor 148, the insertion direction of the ear canal insertion unit 104 is deviated from the eardrum 202. A message is displayed on the display 114, a buzzer 158 is sounded, or a voice 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 region of the eardrum 202 cannot be recognized is notified, the user may adjust the insertion direction of the ear canal insertion unit 104 by moving the biological information measurement device 400.

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

  As a result of the image recognition, when the microcomputer 110 determines that the region of the eardrum 202 has been recognized in the image captured by the image sensor 148, a message indicating that the region 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. By notifying the user that the region of the eardrum 202 has been recognized, the user can grasp that the measurement has been started. Therefore, the biological information measuring device 100 may be stopped without moving. Can be recognized.

  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, infrared light is automatically emitted from the infrared continuous light source 159, and the microcomputer 110 By starting the operations of the chopper 118 and the rotating plate 302, the measurement of the reflected light of the infrared light from the eardrum 202 is started.

  The microcomputer 110 rotates the rotating plate 302 only when the opening 304 corresponding to the position of the pixel capturing the eardrum 202 comes on the optical path of the infrared light emitted from the infrared continuous light source 159. The operation of the infrared continuous light source 159 is controlled so that infrared light is emitted from the infrared continuous light source 159.

  Even after the measurement of infrared light is started, the process for recognizing the region of the eardrum in the image photographed by the image sensor 148 is continuously performed. If the user removes the ear canal insertion portion 104 from the ear canal 200 or moves the ear canal insertion portion 104 greatly during the measurement, the microcomputer 110 is photographed by the image sensor 148. By determining that there is no image corresponding to the eardrum 202 in the captured image, an erroneous operation of the user is detected. Along with this detection, the microcomputer 110 rotates the rotating plate 302 to a portion where the opening 304 of the rotating plate 302 is not present, and blocks infrared light. Further, the microcomputer 110 displays a message on the display 114 that the insertion direction of the ear canal insertion section 104 is deviated from the eardrum 202, sounds a buzzer 158, and outputs a sound from a speaker (not shown). To notify the user that there is 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 moves the biological information measuring device 400 to reinsert the ear canal insertion unit 104 into the ear canal 200 or the insertion direction of the ear canal insertion unit 104. After adjusting, 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 infrared continuous light source 159 to block infrared light. 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 ear canal insertion part 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 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 the present embodiment, the measured signal can be corrected by correcting the number of apertures irradiated with infrared light by the number of all apertures.

  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.

  As described above, according to the biological information measuring apparatus 400 according to the present embodiment, the infrared light applied to the portions other than the eardrum 202 is blocked by using the rotating plate 302 having a plurality of openings 304, thereby enabling the embodiment. Similarly to the biological information measuring apparatus 100 according to No. 1, since it is possible to irradiate only the eardrum 202 with infrared light, the influence of the external auditory canal 204 can be removed, and high-precision measurement can be performed. Further, the measurement accuracy can be further improved by correcting the measured signal by the area irradiated with infrared light.

  In addition, according to biological information measuring apparatus 400 according to the present embodiment, by using rotating plate 302 having a plurality of openings 304, a configuration that is less expensive than a liquid crystal shutter can be achieved.

  In the present embodiment, the diameter of the opening 304 is set to one fifth of the diameter of the irradiated infrared light beam, but the present invention is not limited to this. There is a portion where the diameter of the opening 304 is smaller than the diameter of the irradiated infrared light beam, and the infrared light irradiation area that has passed through each opening 304 overlaps the infrared light irradiation area that has passed through the other opening 304. A plurality of openings 304 may be provided so as not to occur. Further, in the present embodiment, the shape of the opening 304 is a circle, but is not limited thereto. The shape of the opening 304 may be a polygon such as a quadrangle or a pentagon.

  In the present embodiment, the shape of the rotating plate 302 is a circle, but is not limited to this. The shape of the rotating plate 302 may be a semicircle, a sector, or the like.

  Further, in the present embodiment, the infrared continuous light source 159 is only provided when the opening 304 corresponding to the position of the pixel imaging the eardrum 202 is on the optical path of the infrared light emitted from the infrared continuous light source 159. Although the operation of the infrared continuous light source 159 is controlled so that infrared light is emitted from the light source, the present invention is not limited to this. Instead, the infrared continuous light source 159 always emits infrared light, and an aperture 304 that does not correspond to the position of the pixel that images the eardrum 202 is emitted from the infrared continuous light source 159. The microcomputer 110 may control the chopper 118 so that the infrared light is blocked by the chopper 118 when it comes on the optical path of the infrared light. Further, a second shutter is provided between the infrared continuous light source 159 and the third half mirror 145, preferably between the infrared lens 160 and the third half mirror 145. When the opening 304 that does not correspond to the position of the pixel that images the eardrum 202 comes on the optical path of the infrared light emitted from the infrared continuous light source 159 so that infrared light is always emitted, The microcomputer 110 may control the second shutter so that infrared light is blocked by the second shutter. Note that when infrared light is blocked using the chopper 118 or the second shutter, it is not necessary to provide an irradiation position with no opening on the rotating plate 302.

  In addition, by controlling the apparatus so that infrared light is irradiated only to the opening 304 corresponding to the position of the pixel that images the eardrum 202, only the eardrum 202 is irradiated with infrared light. It is not limited to this. Instead, regardless of whether or not the aperture 304 on the optical path of the infrared light emitted from the infrared continuous light source 159 is the aperture 304 corresponding to the position of the pixel imaging the eardrum 202, Infrared light is irradiated to the opening 304 on the optical path of the infrared light emitted from the infrared continuous light source 159 so that the living tissue other than the eardrum 202 is also irradiated with infrared light. Good. In this case, the microcomputer 110 outputs a digital signal output from the A / D converter 138 to a pixel in which the opening 304 on the optical path of the infrared light emitted from the infrared continuous light source 159 images the eardrum 202. The signal is output when the aperture 304 corresponds to the position of the aperture or the signal output when the aperture 304 does not correspond to the position of the pixel imaging the eardrum 202. Store in the memory 112. When obtaining the concentration of the biological component, the microcomputer 110 outputs a signal output when the opening 304 corresponds to the position of the pixel that is imaging the eardrum 202 from the digital signal stored in the memory 112. The extracted digital signal is converted into the concentration of the biological component with reference to correlation data indicating the correlation between the digital signal stored in the memory 112 and the concentration of the biological component. By doing so, since the concentration of the biological component can be obtained using only the electrical signal detected when the eardrum 202 is irradiated with infrared light, the influence of the ear canal 204 can be removed, High-precision measurement can be performed.

  Although the infrared continuous light source 159 is used in the above embodiment, an infrared pulse light source may be used instead. When an infrared pulse light source is used, it is not necessary to use the chopper 118 for converting into a high-frequency infrared light signal. When the chopper 118 is not used with the infrared pulse light source, the electric signal amplified by the preamplifier 130 is removed by the band filter 132 from signals other than the frequency band centered on the repetition frequency of the infrared pulse light source. . The electrical signal filtered by the band filter 132 may be demodulated into a DC signal by synchronizing and integrating with the repetition frequency of the infrared pulse light source by the synchronous demodulator 134.

  Moreover, although the above embodiment demonstrated the example using the infrared light source which radiates | emits various wavelengths, it replaced with this, for example of specific wavelength, such as infrared LED, an infrared laser, a quantum cascade laser, etc. An infrared light source capable of emitting light may be used. When an infrared light source that can emit light of a specific wavelength is used, the optical filter wheel 106 may not be used because infrared light does not have to be dispersed.

  The present invention is useful for noninvasive measurement of biological information, for example, measuring the concentration of biological components such as glucose concentration without collecting blood.

The perspective view which shows the external appearance of the biological information measuring device in one embodiment of this invention The figure which shows the structure of the biometric information measuring device The perspective view which shows the optical wheel in the biological information measuring device The image figure which shows the image when the inside of the ear canal is observed using the biometric information measuring device The figure which shows the structure of the biometric information measuring apparatus in other embodiment of this invention. The front view of the rotating plate seen from the direction of arrow X in FIG. The figure which shows arrangement | positioning of the rotating plate in a biological information measuring device, an infrared continuous light source, an infrared-light lens, and a chopper.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100,400 Biological information measuring device 101 Power switch 102 Case 103 Measurement start switch 104 Ear hole insertion part 105 Light guide part 106 Optical filter wheel 108 Infrared light 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 region 130 Preamplifier 132 Band filter 134 Synchronous demodulator 136 Low pass filter 138 A / D converter 140 Imaging light source 142 First half mirror 144 Second Half mirror 145 Third half mirror 146 Condensing lens 148 Image sensor 150 Actuator 152 Lens frame 154 Position sensor 156 Timer 1 8 buzzer 159 infrared continuous light source 160 infrared lens 200 ear canal 202 tympanic membrane 204 ear canal 302 rotating plate 303 irradiated position 304 aperture

Claims (3)

An infrared light source that emits infrared light irradiated into the ear canal,
A light guide for guiding the infrared light into the ear canal;
Visual field recognition means for recognizing a region capturing the eardrum among the visual field of the light guide unit,
A shutter that is disposed at a position crossing the optical path of the infrared light and controls a region through which the infrared light passes;
An infrared light detector for detecting reflected light of the infrared light reflected in the ear canal; and of the reflected light, an output of the infrared light detector caused by the reflected light reflected by the eardrum. A biological information measuring device including a biological information calculation unit that calculates biological information by using. The biological information measuring apparatus according to claim 1, wherein the infrared light passing through the shutter is a parallel light flux. The living body information according to claim 1, wherein the biological information calculation unit calculates a ratio of a region capturing the eardrum in the visual field of the light guide unit, and corrects the biological information using the ratio. Information measuring device.

Images