JP4444228B2 - Component concentration measuring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a non-invasive biological component concentration measuring apparatus, especially the component concentration measuring apparatus for measuring information on the distribution or concentration of hemoglobin as a blood component inside a living body, the component concentration measuring apparatus having the high detection accuracy of photoacoustic signals. <P>SOLUTION: The component concentration measuring apparatus has a resonator for resonating by the photoacoustic signals radiated from a subject and a reflection part in an ellipsoid shape for reflecting the photoacoustic signals radiated from the subject. In the component concentration measuring apparatus, liquid having an acoustic impedance roughly equal to the one of the subject is filled inside a container and the radius of the resonator is set to be the integer multiple of the half wavelength of the photoacoustic signals propagated in the liquid. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a noninvasive living body component concentration measuring apparatus, and more particularly, to a component concentration measuring apparatus that measures hemoglobin distribution or concentration information as a blood component in a living body.

  With the progress of aging, the response to adult diseases such as cardiovascular diseases has become a major social issue. In particular, information related to blood circulation is attracting attention as it is important information for maintaining health and diagnosing diseases.

  A conventional biological imaging apparatus will be described with reference to FIGS. 12 and 13 (see, for example, Non-Patent Document 1). FIG. 12 is a cross-sectional view of the biological imaging apparatus 100. FIG. 12 illustrates a subject 101, a water tank 111, water 112, a pulse light source 121, a concave mirror 122, a lens 123, an ultrasonic detector 124, a signal processor 125, and a step motor 128.

  FIG. 13 is a top view of the biological imaging apparatus 100. In FIG. 13, the subject 101, the water tank 111, the water 112, the ultrasonic detection unit 124, and the rotation trajectory 130 are illustrated.

  The water tank 111 is filled with water 112. The DUT 101 is submerged in the water 112. The DUT 101 is irradiated with pulsed light output from the pulse light source 121 through the concave mirror 122 and the lens 123. For example, the device under test 101 can be a rat equipped with a respiratory organ.

  The device under test 101 absorbs the irradiated pulsed light inside the device under test 101, and an ultrasonic wave called a pulsed photoacoustic signal is generated. The ultrasonic detection unit 124 detects the photoacoustic signal while moving the rotation track 130 around the DUT 101 by the step motor 128, and converts the photoacoustic signal into an electric signal proportional to the sound pressure. The signal processing unit 125 calculates the component concentration of the measurement target of the DUT 101 based on the electrical signal input from the ultrasonic detection unit 124.

“Nonvasive laser-induced photoacoustic tomography for structural and functional in vivo imaging of the brain.” Xueding Wang et al. 21, Number 7, July 2003.

  However, since the photoacoustic signal is detected by the rotating trajectory 130 having a certain distance, the sound pressure of the photoacoustic signal reaching the ultrasonic detection unit 124 is small, and the biological imaging apparatus 100 has a detection accuracy of the photoacoustic signal. There are issues to be reduced.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a component concentration measuring apparatus with high photoacoustic signal detection accuracy.

  In order to achieve the above object, the first invention of the present application includes a resonator that resonates with a photoacoustic signal radiated from a subject, and an ellipsoidal reflecting portion that reflects the photoacoustic signal radiated from the subject. It is a component concentration measuring device provided.

  Specifically, the first invention of the present application includes a light generation unit that generates light, a light pulse modulation unit that performs pulse modulation on the light generated by the light generation unit and outputs pulsed light, and the light pulse modulation unit. Is irradiated from the subject, a light irradiating unit that irradiates the subject with the pulsed light output by the laser, a spherical or cylindrical resonator that resonates with the photoacoustic signal emitted from the subject by the pulsed light, and the subject. A reflection part that reflects the photoacoustic signal and has at least a part of an ellipsoidal surface; and detects the photoacoustic signal that the reflection part reflects or radiates from the subject; An ultrasonic wave detection unit disposed at a focal point, and an insertion for mounting at least the resonator, the reflection unit, and the ultrasonic wave detection unit and inserting the subject to be disposed at a second focal point of the reflection unit A container having a mouth, An apparatus, said resonator is a constituent concentration measuring apparatus, wherein the disposed inside the reflecting portion so as to surround the subject be located in the second focal point of the reflector portion.

  The ellipsoidal surface is a shape of a hollow structure in which the ellipse is rotated about the major axis.

  The resonator is resonated with the photoacoustic signal radiated from the subject, and the photoacoustic signal radiated from the subject has an amplitude by being arranged so that the resonator surrounds the subject. Is amplified. In addition, since at least a part of the reflecting portion has an ellipsoidal surface, the photoacoustic signal radiated from the subject arranged at the second focus is efficiently transmitted to the first focus of the reflecting portion. Reflected. Therefore, the ultrasonic detection unit arranged at the first focal point of the reflection unit has high detection accuracy. Therefore, it is possible to provide a component concentration measuring apparatus with high photoacoustic signal detection accuracy.

  In order to achieve the above object, the second invention of the present application includes a resonator that resonates with a photoacoustic signal radiated from a subject and an elliptical cylindrical reflecting portion that reflects the photoacoustic signal radiated from the subject. It is a component concentration measuring device provided.

  Specifically, the second invention of the present application includes a light generation unit that generates light, a light pulse modulation unit that performs pulse modulation on the light generated by the light generation unit and outputs pulse light, and the light pulse modulation unit. Is irradiated from the subject, a light irradiating unit that irradiates the subject with the pulsed light output by the laser, a spherical or cylindrical resonator that resonates with the photoacoustic signal emitted from the subject by the pulsed light, and the subject. Reflecting the photoacoustic signal, at least a part of which is an elliptical cylinder, and detecting the photoacoustic signal reflected by the reflecting unit or radiated from the subject. An ultrasonic wave detection unit disposed at a focal point, and an insertion for mounting at least the resonator, the reflection unit, and the ultrasonic wave detection unit and inserting the subject to be disposed at a second focal point of the reflection unit Component concentration measurement comprising a container having a mouth A location, the resonator is a constituent concentration measuring apparatus, wherein the disposed inside the reflecting portion so as to surround the subject be located in the second focal point of the reflector portion.

  An elliptic cylinder is a cylinder whose section of the minimum area is an ellipse.

  The resonator is resonated with the photoacoustic signal radiated from the subject, and the photoacoustic signal radiated from the subject has an amplitude by being arranged so that the resonator surrounds the subject. Is amplified. In addition, since at least a part of the reflecting portion has an elliptical cylindrical shape, the photoacoustic signal radiated from the subject arranged at the second focus is efficiently transmitted to the first focus of the reflecting portion. Reflected. Therefore, the ultrasonic detection unit arranged at the first focal point of the reflection unit has high detection accuracy. Therefore, it is possible to provide a component concentration measuring apparatus with high photoacoustic signal detection accuracy.

  In order to achieve the above object, the third invention of the present application reflects a resonator that resonates with a photoacoustic signal radiated from a subject and a photoacoustic signal radiated from the subject, and an axis passing through each focal point. It is a component concentration measuring apparatus provided with two rotating paraboloid-shaped reflecting parts whose inner surfaces are opposed to each other.

  Specifically, the third invention of the present application includes a light generation unit that generates light, a light pulse modulation unit that performs pulse modulation on the light generated by the light generation unit and outputs pulse light, and the light pulse modulation unit. Is irradiated from the subject, a light irradiating unit that irradiates the subject with the pulsed light output by the laser, a spherical or cylindrical resonator that resonates with the photoacoustic signal emitted from the subject by the pulsed light, and the subject. Two reflecting parts that reflect the photoacoustic signal, at least part of which is a paraboloid, and whose inner surfaces face each other so that axes passing through the respective focal points coincide with each other; An ultrasonic detection unit that detects the photoacoustic signal emitted from the subject and is disposed at the focal point of one of the reflection units, and includes at least the resonator, the two reflection units, and the ultrasonic detection unit And inserting the subject into the other And a container having an insertion port for placing at the focal point of the projecting part, wherein the resonator surrounds the subject to be placed at the focal point of the other reflecting part. It is a component concentration measuring device, which is arranged on the inner surface side of the reflecting portion.

  The resonator is resonated with the photoacoustic signal radiated from the subject, and the photoacoustic signal radiated from the subject has an amplitude by being arranged so that the resonator surrounds the subject. Is amplified. Further, at least a part of the reflecting part is a paraboloid, and the inner surfaces of the two reflecting parts are opposed to each other so that the axes passing through the respective focal points coincide with each other. The photoacoustic signal radiated from the subject arranged at the focal point is efficiently reflected by the one reflecting portion. Furthermore, by separating the two reflecting parts, the ultrasonic detecting part can reduce noise. Therefore, the ultrasonic detection unit arranged at the focal point of the one reflection unit has high detection accuracy. Therefore, it is possible to provide a component concentration measuring apparatus with high photoacoustic signal detection accuracy.

  In order to achieve the above object, the fourth invention of the present application reflects a resonator that resonates with a photoacoustic signal radiated from a subject and a photoacoustic signal radiated from the subject. It is a component concentration measuring apparatus provided with two parabolic curved plate-like reflecting portions whose inner surfaces are opposed to each other.

  Specifically, the fourth invention of the present application includes a light generation unit that generates light, a light pulse modulation unit that performs pulse modulation on the light generated by the light generation unit and outputs pulse light, and the light pulse modulation unit. Is irradiated from the subject, a light irradiating unit that irradiates the subject with the pulsed light output by the laser, a spherical or cylindrical resonator that resonates with the photoacoustic signal emitted from the subject by the pulsed light, and the subject. Two reflecting portions that reflect the photoacoustic signal, at least part of which is a parabolic curved plate, and whose inner surfaces face each other so that axes passing through the respective focal points coincide, and the reflecting portion reflects or An ultrasonic detection unit that detects the photoacoustic signal emitted from the subject and is disposed at the focal point of one of the reflection units, and includes at least the resonator, the two reflection units, and the ultrasonic detection unit And inserting the subject into the other And a container having an insertion port for placing at the focal point of the projecting part, wherein the resonator surrounds the subject to be placed at the focal point of the other reflecting part. It is a component concentration measuring device, which is arranged on the inner surface side of the reflecting portion.

  A parabolic curved plate is a plate whose cross section is a parabola.

  The resonator is resonated with the photoacoustic signal radiated from the subject, and the photoacoustic signal radiated from the subject has an amplitude by being arranged so that the resonator surrounds the subject. Is amplified. In addition, at least a part of the reflection part is a parabolic curved plate, and the inner surfaces of the two reflection parts are opposed to each other so that axes passing through the respective focal points coincide with each other. The photoacoustic signal radiated from the subject arranged at the focal point is efficiently reflected by the one reflecting portion. Furthermore, by separating the two reflecting parts, the ultrasonic detecting part can reduce noise. Therefore, the ultrasonic detection unit arranged in the one reflection unit has high detection accuracy. Therefore, it is possible to provide a component concentration measuring apparatus with high photoacoustic signal detection accuracy.

  In each invention of the present application, the container is filled with a liquid having an acoustic impedance substantially equal to that of the subject, and the resonator has a radius of k / 2 times the wavelength of the photoacoustic signal propagating in the liquid. (K is an integer of 1 or more).

  Since the acoustic impedance of the liquid and the acoustic impedance of the subject are substantially equal, the photoacoustic signal is difficult to reduce. In addition, since the radius of the resonator is k / 2 times the wavelength of the photoacoustic signal propagating in the liquid, the amplitude of the photoacoustic signal is further amplified. Therefore, the ultrasonic detection unit has higher detection accuracy of the photoacoustic signal. Therefore, it is possible to provide a component concentration measuring device with higher photoacoustic signal detection accuracy.

  In each invention of the present application, the high acoustic impedance layer is m / 4 times the wavelength of the photoacoustic signal propagating through the high acoustic impedance layer, and the low acoustic impedance layer is the thickness of the low acoustic impedance layer. The thickness is n / 4 times the wavelength of the photoacoustic signal propagating in the interior, and at least a part of the reflection portion is alternately laminated with the high acoustic impedance layer and the low acoustic impedance layer. Preferred (m and n are odd numbers of 1 or more).

  The acoustic impedances of the two layers are compared, and the higher acoustic impedance is defined as the high acoustic impedance layer, and the lower acoustic impedance is defined as the low acoustic impedance layer.

  Since at least a part is the high acoustic impedance layer and the low acoustic impedance layer having a predetermined thickness, the reflective portion can have a higher reflectance. Therefore, the ultrasonic detection unit has higher detection accuracy of the photoacoustic signal. Therefore, it is possible to provide a component concentration measuring device with higher photoacoustic signal detection accuracy.

  In each invention of the present application, the high acoustic impedance layer is p / 4 times the wavelength of the photoacoustic signal propagating through the high acoustic impedance layer, and the low acoustic impedance layer is the thickness of the low acoustic impedance layer. The thickness of the resonator is q / 4 times the wavelength of the photoacoustic signal propagating inside, and at least a part of the resonator is formed by alternately stacking the high acoustic impedance layer and the low acoustic impedance layer. Preferred (p and q are odd numbers of 1 or more).

  Since the high acoustic impedance layer and the low acoustic impedance layer having a predetermined thickness are at least partially, the resonator can have higher reflectance. Therefore, the ultrasonic detection unit has higher detection accuracy of the photoacoustic signal. Therefore, it is possible to provide a component concentration measuring device with higher photoacoustic signal detection accuracy.

  The present invention can provide a component concentration measuring apparatus with high photoacoustic signal detection accuracy.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that portions that can be realized by a normal technique such as a control unit that controls the overall operation are not shown.

(Embodiment 1)
In the first embodiment of the present application, a light generation unit that generates light, a light pulse modulation unit that performs pulse modulation on the light generated by the light generation unit to output pulse light, and a light pulse modulation unit that outputs the light A light irradiation unit that irradiates the subject with the pulsed light, a spherical or cylindrical resonator that resonates with a photoacoustic signal radiated from the subject by the pulsed light, and the photoacoustic radiated from the subject A reflection part that reflects a signal and has at least a part of an ellipsoidal surface, and the photoacoustic signal that the reflection part reflects or radiates from the subject is detected and arranged at the first focal point of the reflection part An ultrasonic detection unit, and at least the resonator, the reflection unit, and the ultrasonic detection unit, and an insertion port for inserting the subject and placing the subject at the second focal point of the reflection unit A component concentration measuring device comprising: There are, the resonator is a constituent concentration measuring apparatus, wherein the disposed inside the reflecting portion so as to surround the subject be located in the second focal point of the reflector portion.

  A component concentration measuring apparatus 10 according to the first embodiment of the present application will be described with reference to FIGS. 1 and 2. FIG. 1 is a schematic diagram of a component concentration measuring apparatus 10. In FIG. 1, a light generation unit 21, an optical pulse modulation unit 22, a light irradiation unit 23, a resonator 24, a support 24a, a reflection unit 25, an ultrasonic detection unit 26, a container 27, an insertion port 27a, a window unit 27b, light The fiber 28, the support 29, the preamplifier 30, the signal processing unit 31, and the subject 90 are shown.

  FIG. 2 is a perspective view of the component concentration measuring apparatus 10 as viewed from above. FIG. 2 illustrates the resonator 24, the reflection unit 25, the ultrasonic detection unit 26, the container 27, the window 27b, the pulsed light 41, the photoacoustic signal 42, and the subject 90. Note that the pulsed light 41 is light emitted from the light irradiation unit 23 to the subject 90, and the photoacoustic signal 42 is generated inside the subject 90 by the pulsed light 41. The subject 90 is a human finger.

  The configuration of the component concentration measuring apparatus 10 will be described. The light generator 21 generates light. The light generation unit 21 may be connected to the optical pulse modulation unit 22 through an optical signal transmission unit. For example, examples of the light generating unit 21 include light emitting elements such as lamps, semiconductor lasers, solid state lasers, and light emitting diodes. The optical signal transmission means may be an optical fiber or an optical waveguide, and the same applies to the following description.

For the reason described later, the component concentration measuring apparatus 10 preferably fills the container 27 with a liquid having substantially the same acoustic impedance as the subject 90. For example, the acoustic impedance of the subject 90 is substantially equal to the acoustic impedance of water. Therefore, when water is filled in the container 27, the light generation unit 21 has a wavelength at which blood exhibits absorption without exhibiting characteristic absorption of water, and a wavelength at which light can be emitted by a laser, a light emitting element, or the like. It is preferable to generate light. For example, the absorption coefficient of water at a wavelength of 800nm is approximately 0.023 ^-1, the absorption coefficient of blood is approximately 1.0 cm ^-1, meeting the above criteria.

  The optical pulse modulator 22 performs pulse modulation on the light generated by the light generator 21 and outputs pulsed light 41. The optical pulse modulation unit 22 may be connected to the light irradiation unit 23 via an optical signal transmission unit. For example, as the optical pulse modulator 22, there is a method of electrically or electro-optically modulating light supplied from the light generator 21.

  In order to irradiate the subject 90 with the pulsed light 41 and appropriately reflect the absorption by the subject 90 in the photoacoustic signal 42, the pulse width of the pulsed light 41 is preferably 10 nanoseconds or less. The repetition frequency is preferably 1 kilohertz or more in order to shorten the measurement time.

  Further, when the semiconductor laser is directly modulated, the light generation unit 21 and the optical pulse modulation unit 22 can be integrated. For example, when modulated directly, the semiconductor laser can generate pulsed light 41 having a pulse width of 10 nanoseconds or less. Furthermore, the Q-switched YAG laser can generate the same pulsed light 41 as described above.

  The light irradiation unit 23 irradiates the subject 90 with the pulsed light 41 output from the light pulse modulation unit 22. The light irradiation unit 23 may be connected to one end of the optical fiber 28. For example, the light irradiation unit 23 may be a material transparent to other pulsed light 41 such as glass or plastic. Further, when the container 27 is filled with a liquid having substantially the same acoustic impedance as the subject 90 and the light irradiation unit 23 comes into contact with the liquid, the light irradiation unit 23 does not chemically react with the liquid. It may be. For example, when the inside of the container 27 is filled with water, the light irradiation unit 23 may be quartz glass, optical glass, or sapphire glass.

  The other end of the optical fiber 28 may be connected to the outer surface of a window 27b of the container 27 described later. Then, the freedom degree of the arrangement place of the light generation part 21 and the optical pulse modulation part 22 can be enlarged. Further, the optical fiber 28 may be omitted, and the light irradiation unit 23 may be connected to the outer surface of the window portion 27b. Alternatively, the light irradiation unit 23 may be provided inside the container 27 and the reflection unit 25 by removing the window 27 b.

  The resonator 24 resonates with the photoacoustic signal 42 emitted from the subject 90 by the pulsed light 41. The resonator 24 may be hemispherical. Further, the resonator 24 may be fixed to the reflecting portion 25 via the support column 24a. Note that the resonator 24 may be elliptical or spherical as described later.

  The reflection unit 25 reflects the photoacoustic signal 42 emitted from the subject 90 by the pulsed light 41. The reflection unit 25 may be disposed inside the container 27 or may be composed of the inner surface of the container 27. When the container 27 is filled with a liquid having substantially the same acoustic impedance as that of the subject 90, the reflection unit 25 has a high reflectance with respect to the photoacoustic signal 42, and does not chemically react with the liquid. The material may be For example, when the container 27 is filled with water, examples of the material of the reflecting portion 25 include stainless steel and aluminum.

  The reflecting portion 25 has an ellipsoidal surface and has two focal points. Hereinafter, one of the two focal points is a first focal point, and the other is a second focal point. Any focus may be used as the first focus.

  The container 27 carries at least the resonator 24, the reflection unit 25, and the ultrasonic detection unit 26. In addition, the container 27 may be provided with an insertion port 27a for placing the subject 90 at the second focal point on a part of the upper surface and a window part 27b on the side surface. For example, as a material of the container 27, an epoxy resin containing metal oxide powder such as titanium oxide or tungsten oxide can be used. By providing the window portion 27b, the container 27 can reduce the unevenness of the inner surface, and can reduce unnecessary reflection of the photoacoustic signal 42.

  The support 29 may have a space in which the signal transmission means is disposed inside, and may be provided through the reflecting portion 25 and the container 27 from the upper surface of the container 27. Further, the support 29 may be provided so that an ultrasonic detection unit 26 described later is disposed at the first focal point of the reflection unit 25. For example, the material of the support 29 can be the same material as the container 27 that does not reflect the photoacoustic signal 42.

  The ultrasonic detection unit 26 detects the photoacoustic signal 42 reflected by the reflection unit 25. The ultrasonic detection unit 26 is provided at the end of the support 29, is disposed at the first focal point of the reflection unit 25, and is connected to the preamplifier 30 via signal transmission means that penetrates the support 29. May be. For example, as the ultrasonic detection unit 26, a ceramic microphone using a piezoelectric effect or an electrostrictive effect, a ceramic ultrasonic sensor, a dynamic microphone using electromagnetic induction, a ribbon microphone, a condenser microphone using an electrostatic effect, etc. Examples thereof include a magnetostrictive vibrator using the magnetostrictive effect and an optical microphone using the light reflection / diffraction effect. Further, when the piezoelectric effect is used, it may be composed of PZT crystal or PVDF crystal. Moreover, a copper cable can be mentioned as a signal transmission means, and it is the same also in the following description.

  For example, when the inside of the container 27 is filled with water, the ultrasonic detection unit 26 detects the photoacoustic signal 42 transmitted through the water, and therefore the ultrasonic detection unit 26 may be an underwater microphone such as a needle hydrophone. Can do. Further, a matching layer of silicon rubber may be provided on the surface of the ultrasonic detection unit 26 for acoustic impedance matching with water.

  The preamplifier 30 may receive a signal obtained by detecting the photoacoustic signal 42 transmitted from the ultrasonic detection unit 26, amplify the photoacoustic signal 42, and then transmit the signal to the signal processing unit 31. The preamplifier 30 may be connected to the signal processing unit 31 through signal transmission means.

  The signal processing unit 31 may calculate the concentration of the component to be measured by the subject 90 based on the signal obtained by detecting the photoacoustic signal 42 transmitted from the preamplifier 30. Further, the signal processing unit 31 includes means for displaying the calculation result, means for imaging the concentration distribution of the measurement target component inside the subject 90, and means for recording the calculation result and the like. Good.

  For example, the component concentration measuring apparatus 10 may arrange a sound absorbing material on the upper surface of the container 27 for reducing noise that enters from the insertion port 27a.

  For example, when filling the inside of the container 27 with water, the component concentration measuring apparatus 10 has a temperature detecting means for detecting the temperature of water inside the container 27 and a temperature adjusting means for adjusting the temperature of the water. (It is not shown in FIGS. 1 and 2).

  The point that the photoacoustic signal detection accuracy of the component concentration measuring apparatus 10 is high will be described. First, the pulsed light 41 is applied to the subject 90. The pulsed light 41 irradiated to the subject 90 is absorbed inside the subject 90. The subject 90 that has absorbed the pulsed light 41 emits the photoacoustic signal 42 in all directions. When the resonator 24 resonates with the photoacoustic signal 42, the amplitude of the photoacoustic signal 42 radiated from the subject 90 is amplified. In addition, since at least a part of the reflection unit 25 has an ellipsoidal shape, the reflection unit 25 efficiently reflects the photoacoustic signal 42 with the amplified amplitude to the ultrasonic detection unit 26 disposed at the first focus. . The ultrasonic detector 26 transmits a signal obtained by detecting the photoacoustic signal 42 whose amplitude is amplified to the preamplifier 30. As described above, based on the photoacoustic signal 42 increased by the preamplifier 30, the signal processing unit 31 calculates the concentration of the component to be measured by the subject 90. As described above, the amplitude of the photoacoustic signal 42 is amplified, and the reflection unit 25 efficiently reflects the photoacoustic signal 42 to the ultrasonic detection unit 26, so that the ultrasonic detection unit 26 has high detection accuracy. Therefore, it is possible to provide a component concentration measuring apparatus with high photoacoustic signal detection accuracy.

  In the first embodiment of the present application, the container is filled with a liquid having an acoustic impedance substantially equal to that of the subject, and the resonator has a radius k of the wavelength of the photoacoustic signal propagating in the liquid. / 2 times is preferable (k is an integer of 1 or more).

  FIG. 3A is an enlarged view seen from the upper surface of the spherical resonator 24. FIG. 3B is an enlarged view seen from the side of the spherical resonator 24. 3A and 3B show the resonator 24. FIG. The radius of the resonator 24 is shown as r.

  The container 27 is preferably filled with a liquid having an acoustic impedance substantially equal to that of the subject 90 inside. As described above, water can be used as the liquid having an acoustic impedance substantially equal to that of the subject 90 that is a human finger. Since the acoustic impedance of water and the acoustic impedance of the subject 90 are substantially equal, the photoacoustic signal 42 is efficiently transmitted from the subject 90 to the water and is difficult to reduce.

  The resonator 24 preferably has a radius of k / 2 times the wavelength of the photoacoustic signal 42 propagating in the liquid. For example, when the subject 90 emits a photoacoustic signal 42 having a frequency of 1605 kilohertz when irradiated with the pulsed light 41 in the atmosphere, the above-described photoacoustic signal 42 in water has a wavelength of 2.47 millimeters. For example, k may be 10 and the radius r of the resonator 24 may be 12.35 millimeters. Then, the resonator 24 resonates more strongly, and the amplitude of the photoacoustic signal 42 is further amplified. Therefore, the ultrasonic detection unit 26 has higher detection accuracy of the photoacoustic signal. Therefore, it is possible to provide a component concentration measuring device with higher photoacoustic signal detection accuracy.

  In the first embodiment of the present application, the high acoustic impedance layer has a thickness of m / 4 times the wavelength of the photoacoustic signal propagating through the high acoustic impedance layer, and the low acoustic impedance layer includes the low acoustic impedance layer. The thickness is n / 4 times the wavelength of the photoacoustic signal propagating in the impedance layer, and at least a part of the reflection portion is alternately laminated with the high acoustic impedance layer and the low acoustic impedance layer. (M and n are odd numbers of 1 or more).

  FIG. 4 is an enlarged view of a cross section of the reflecting portion 25. FIG. 4 illustrates the high acoustic impedance layer 33 and the low acoustic impedance layer 34.

If the material of the high acoustic impedance layer 33 is a metal, the material of the low acoustic impedance layer 34 may be glass or plastic. If the material of the high acoustic impedance layer 33 is metal or glass, the material of the low acoustic impedance layer 34 may be plastic. Considering the difference in acoustic impedance between the high acoustic impedance layer 33 and the low acoustic impedance layer 34 and workability, it is preferable that the material of the high acoustic impedance layer 33 is a metal and the material of the low acoustic impedance layer 34 is a plastic. For example, aluminum (Al) having an acoustic impedance of 17.3 × 10 ⁶ Ns / m ³ as the high acoustic impedance layer 33 and an epoxy having an acoustic impedance of 6.7 × 10 ⁶ Ns / m ³ as the low acoustic impedance layer 34 Can give.

  The thickness a of the high acoustic impedance layer 33 is preferably m / 4 times the wavelength of the photoacoustic signal 42 propagating through the high acoustic impedance layer 33. The thickness b of the low acoustic impedance layer 34 is preferably n / 4 times the wavelength of the photoacoustic signal 42 propagating through the low acoustic impedance layer 34 (m and n are odd numbers of 1 or more). ). For example, it is assumed that the high acoustic impedance layer 33 is aluminum and the low acoustic impedance layer 34 is epoxy. When the subject 90 emits the pulsed light 41 in the atmosphere, when the photoacoustic signal 42 having a frequency of 1605 kilohertz is emitted, the wavelength of the photoacoustic signal 42 in aluminum becomes 4.00 millimeters, and the photoacoustic signal in the epoxy. The wavelength of 42 is 1.55 millimeters. Therefore, m may be 1, the thickness a of the high acoustic impedance layer 33 may be 1.00 millimeter, n may be 1, and the thickness b of the low acoustic impedance layer 34 may be 0.39 millimeter. Note that m and n need not have the same value.

  Since at least a part is the high acoustic impedance layer 33 and the low acoustic impedance layer 34 having a predetermined thickness, the reflection unit 25 can further increase the reflectance. Therefore, the ultrasonic detection unit 26 has higher detection accuracy of the photoacoustic signal 42. Therefore, it is possible to provide a component concentration measuring device with higher photoacoustic signal detection accuracy. In the following embodiments of the present application, the effect of using at least a part of the reflecting portion 25 as the high acoustic impedance layer 33 and the low acoustic impedance layer 34 having a predetermined thickness is the same, and the above description is omitted.

ここで、Ｒは反射率、ｐは密度、Ｎは反射の次数、ｚ_ｌは外界物質（例えば、水や空気。）の音響インピーダンス密度、ｚ_Ｈは高音響インピーダンス層３３の音響インピーダンス密度、ｚ_Ｌは低音響インピーダンス層３４の音響インピーダンス密度、ｚ_Ｓは基板物質（例えば、反射部２５の材料。）の音響インピーダンス密度、ｈ_Ｈは高音響インピーダンス層３３の膜厚、ｈ_Ｌは低音響インピーダンス層３４の膜厚及びλ_０は光音響信号４２の波長である。 The reflectances of the high acoustic impedance layer 33 and the low acoustic impedance layer 34 having a predetermined thickness can be obtained from the following number (1) to number (3).

Here, R is the reflectance, p is the density, N is the order of reflection, z _l is the acoustic impedance density of the external material (for example, water or air), z _H is the acoustic impedance density of the high acoustic impedance layer 33, z _L is the acoustic impedance density of the low acoustic impedance layer 34, z _S is the acoustic impedance density of the substrate material (for example, the material of the reflector 25), h _H is the film thickness of the high acoustic impedance layer 33, and h _L is the low acoustic impedance. The thickness of the layer 34 and λ ₀ are the wavelengths of the photoacoustic signal 42.

  In the first embodiment of the present application, the high acoustic impedance layer has a thickness of p / 4 times the wavelength of the photoacoustic signal propagating through the high acoustic impedance layer, and the low acoustic impedance layer includes the low acoustic impedance layer. The thickness of the resonator is q / 4 times the wavelength of the photoacoustic signal propagating in the impedance layer, and at least a part of the resonator is alternately laminated with the high acoustic impedance layer and the low acoustic impedance layer. (P and q are odd numbers of 1 or more).

  Similarly to the above, at least a part of the resonator 24 is preferably a high acoustic impedance layer 33 and a low acoustic impedance layer 34 having a predetermined thickness. Then, the resonator 24 can increase the reflectance. Therefore, the ultrasonic detection unit 26 has higher detection accuracy of the photoacoustic signal 42. Therefore, it is possible to provide a component concentration measuring device with higher photoacoustic signal detection accuracy. In the following embodiments of the present application, the effect of using at least a part of the resonator 24 as the high acoustic impedance layer 33 and the low acoustic impedance layer 34 having a predetermined thickness is the same, and the above description is omitted. Also, p and q need not be the same value.

(Embodiment 2)
In the second embodiment of the present application, a light generation unit that generates light, a light pulse modulation unit that performs pulse modulation on the light generated by the light generation unit and outputs pulse light, and a light pulse modulation unit that outputs the light A light irradiation unit that irradiates the subject with the pulsed light, a spherical or cylindrical resonator that resonates with a photoacoustic signal radiated from the subject by the pulsed light, and the photoacoustic radiated from the subject A reflection part that reflects a signal and is at least partially elliptical cylindrical, and detects the photoacoustic signal that the reflection part reflects or radiates from the subject, and is arranged at the first focal point of the reflection part An ultrasonic detection unit, and at least the resonator, the reflection unit, and the ultrasonic detection unit, and an insertion port for inserting the subject and placing the subject at the second focal point of the reflection unit A component concentration measuring device comprising a container I, wherein the resonator is a constituent concentration measuring apparatus, wherein the disposed inside the reflecting portion so as to surround the subject be located in the second focal point of the reflector portion.

  A component concentration measuring apparatus 11 according to the second embodiment of the present application will be described with reference to FIGS. 5 and 6. FIG. 5 is a schematic diagram of the component concentration measuring apparatus 11. In FIG. 5, the light generation unit 21, the optical pulse modulation unit 22, the light irradiation unit 23, the resonator 24, the reflection unit 25, the ultrasonic detection unit 26, the container 27, the insertion port 27 a, the window unit 27 b, the optical fiber 28, The support 29, the signal processing unit 31, the preamplifier 30, the pulsed light 41, the photoacoustic signal 42, and the subject 90 are illustrated.

  FIG. 6 is a perspective view of the component concentration measuring apparatus 11 as viewed from above. FIG. 6 illustrates the resonator 24, the reflection unit 25, the ultrasonic detection unit 26, the container 27, the window 27b, the pulsed light 41, the photoacoustic signal 42, and the subject 90. The component concentration measuring device 11 will be described with respect to parts different from the component concentration measuring device 10 described with reference to FIGS. 1 and 2. The subject 90 is a human finger.

  The resonator 24 may be cylindrical. Further, one end of the resonator 24 may be fixed to the reflecting portion 25.

  The reflection unit 25 has an elliptic cylindrical shape, and has two virtual lines that are a set of focal points. Hereinafter, an arbitrary point on one of the virtual lines is a first focus, and an arbitrary point on the other virtual line is a second focus.

  The point with high detection accuracy of the photoacoustic signal of the component density | concentration measuring apparatus 11 is demonstrated. Similar to the component concentration measuring apparatus 10 of FIGS. 1 and 2, the component concentration measuring apparatus 11 irradiates the subject 90 with the pulsed light 41, and the subject 90 radiates the photoacoustic signal 42 in all directions. The resonator 24 resonates with the signal 42. Then, the amplitude of the photoacoustic signal 42 is amplified. In addition, since at least a part of the reflection unit 25 has an elliptical cylindrical shape, the reflection unit 25 efficiently reflects the photoacoustic signal 42 with the amplified amplitude to the ultrasonic detection unit 26 arranged at the first focus. . Similar to the component concentration measuring apparatus 10 of FIGS. 1 and 2, the amplitude of the photoacoustic signal 42 is amplified, and the reflection unit 25 efficiently reflects the photoacoustic signal 42 to the ultrasonic detection unit 26, thereby detecting ultrasonic waves. The unit 26 has high detection accuracy. Therefore, it is possible to provide a component concentration measuring apparatus with high photoacoustic signal detection accuracy.

  In the second embodiment of the present application, the container is filled with a liquid having an acoustic impedance substantially equal to that of the subject, and the resonator has a radius k of the wavelength of the photoacoustic signal propagating in the liquid. / 2 times is preferable (k is an integer of 1 or more).

  FIG. 7A is an enlarged view seen from the upper surface of the cylindrical resonator 24. FIG. 7B is an enlarged view seen from the side of the cylindrical resonator 24. 7A and 7B show the resonator 24. FIG. The radius of the resonator 24 is shown as r.

  Similarly to the above, the container 27 is preferably filled with a liquid having an acoustic impedance substantially equal to that of the subject 90. The resonator 24 preferably has a radius of k / 2 times the wavelength of the photoacoustic signal 42 propagating in the liquid (k is an integer of 1 or more). Then, the resonator 24 resonates more strongly, and the amplitude of the photoacoustic signal 42 is further amplified. Therefore, the ultrasonic detection unit 26 has higher detection accuracy of the photoacoustic signal. Therefore, it is possible to provide a component concentration measuring device with higher photoacoustic signal detection accuracy. In the following embodiments of the present application, the effect of setting the radius r of the resonator 24 to k / 2 times the wavelength of the photoacoustic signal 42 propagating in the liquid is the same as in the container 27. Therefore, the above description is omitted.

(Embodiment 3)
In the third embodiment of the present application, a light generation unit that generates light, a light pulse modulation unit that performs pulse modulation on the light generated by the light generation unit and outputs pulse light, and a light pulse modulation unit that outputs the light A light irradiation unit that irradiates the subject with the pulsed light, a spherical or cylindrical resonator that resonates with a photoacoustic signal radiated from the subject by the pulsed light, and the photoacoustic radiated from the subject Reflecting signal, at least part of which is a paraboloid, and two reflecting parts facing each other so that the axes passing through the respective focal points coincide with each other, and the reflecting part reflects or from the subject The photoacoustic signal to be radiated is detected, and an ultrasonic detection unit disposed at the focal point of one of the reflection units, and at least the resonator, the two reflection units, and the ultrasonic detection unit are mounted, Insert the subject and the other reflection part And a container having an insertion port for placement at a focal point, wherein the resonator has the other reflecting portion so as to surround the subject to be placed at the focal point of the other reflecting portion. It is arrange | positioned at the said inner surface side of a component concentration measuring apparatus characterized by the above-mentioned.

  The component concentration measuring apparatus 12 according to the third embodiment of the present application will be described with reference to FIGS. FIG. 8 is a schematic diagram of the component concentration measuring device 12. In FIG. 8, the light generation unit 21, the optical pulse modulation unit 22, the light irradiation unit 23, the resonator 24, the support 24a, the reflection unit 25, the ultrasonic detection unit 26, the container 27, the insertion port 27a, the window 27b, the light The fiber 28, the support 29, the preamplifier 30, the signal processing unit 31, the pulsed light 41, the photoacoustic signal 42, and the subject 90 are illustrated.

  FIG. 9 is a perspective view of the component concentration measuring device 12 as seen from the upper surface. FIG. 9 illustrates the resonator 24, the reflection unit 25, the ultrasonic detection unit 26, the container 27, the window 27b, the pulsed light 41, the photoacoustic signal 42, and the subject 90. The subject 90 is a small animal such as a rat. The component concentration measuring device 12 will be described with respect to the differences from the component concentration measuring device 10 described with reference to FIGS. 1 and 2.

  At least a part of the reflecting portion 25 is a paraboloid. Moreover, the reflection part 25 is fixed to the both side surfaces of the container 27 so that the axes passing through the respective focal points coincide and the inner surfaces face each other. Since at least a part is a paraboloid, the reflecting portion 25 has one focal point. Note that the ultrasonic detector 26 may be disposed at the focal point of any of the two reflecting units 25, and the subject 90 may be disposed at the focal point of the remaining reflecting units 25.

  The resonator 24 may be a sphere. For example, the resonator 24 may be kept airtight and may house the subject 90 inside through a door that can be opened and closed. Then, even if the container 27 is filled with a liquid having an acoustic impedance substantially equal to that of the subject 90 such as a rat, the subject 90 can breathe inside the resonator 24 for a certain time.

  The container 27 may be provided with an insertion port 27 a for placing the subject 90 at the focal point of the reflection part 25 where the ultrasonic detector 26 is placed and the other reflection part 25. The container 27 may have a door portion 27c that opens and closes the insertion port 27a. When the subject 90 is accommodated in the resonator 24, the door portion 27c may be opened, and when the subject 90 is accommodated in the resonator 24, the door portion 27c may be closed. By closing the door portion 27c, the component concentration measuring device 12 can reduce noise that enters the upper surface of the container 27 from the insertion port 27a.

  The point that the photoacoustic signal detection accuracy of the component concentration measuring apparatus 12 is high will be described. As in the component concentration measuring apparatus 10 of FIGS. 1 and 2, the subject 90 is irradiated with the pulsed light 41, the subject 90 emits the photoacoustic signal 42 in all directions, and the resonator 24 resonates. Then, the amplitude of the photoacoustic signal 42 is amplified. At least a part of the reflecting portion 25 is a paraboloid, and the inner surfaces face each other so that the axes passing through the respective focal points coincide with each other, so that one reflecting portion 25 receives the photoacoustic signal 42 with an amplified amplitude. The reflected light is efficiently reflected on the ultrasonic detection unit 26 disposed at the focal point of the other reflection unit 25. Similar to the component concentration measuring apparatus 10 of FIGS. 1 and 2, the amplitude of the photoacoustic signal 42 is amplified, and the reflection unit 25 efficiently reflects the photoacoustic signal 42 to the ultrasonic detection unit 26, thereby detecting ultrasonic waves. The unit 26 has high detection accuracy. Therefore, it is possible to provide a component concentration measuring apparatus with high photoacoustic signal detection accuracy.

(Embodiment 4)
In the fourth embodiment of the present application, a light generation unit that generates light, a light pulse modulation unit that performs pulse modulation on the light generated by the light generation unit and outputs pulsed light, and a light pulse modulation unit that outputs the light A light irradiation unit that irradiates the subject with the pulsed light, a spherical or cylindrical resonator that resonates with a photoacoustic signal radiated from the subject by the pulsed light, and the photoacoustic radiated from the subject Reflecting signal, at least part of which is a parabolic curved plate, and two reflecting parts whose inner surfaces face each other so that axes passing through the respective focal points coincide with each other, and the reflecting part reflects or from the subject The photoacoustic signal to be radiated is detected, and an ultrasonic detection unit disposed at the focal point of one of the reflection units, and at least the resonator, the two reflection units, and the ultrasonic detection unit are mounted, Insert the subject and the other reflection part And a container having an insertion port for placement at a focal point, wherein the resonator has the other reflecting portion so as to surround the subject to be placed at the focal point of the other reflecting portion. It is arrange | positioned at the said inner surface side of a component concentration measuring apparatus characterized by the above-mentioned.

  A component concentration measuring apparatus 13 according to the fourth embodiment of the present application will be described with reference to FIGS. 10 and 11. FIG. 10 is a schematic diagram of the component concentration measuring apparatus 13. In FIG. 10, a light generation unit 21, an optical pulse modulation unit 22, a light irradiation unit 23, a resonator 24, a reflection unit 25, an ultrasonic detection unit 26, a container 27, an insertion port 27a, a window unit 27b, an optical fiber 28, The support 29, the preamplifier 30, the signal processing unit 31, the pulsed light 41, the photoacoustic signal 42, and the subject 90 are illustrated.

  FIG. 11 is a perspective view of the component concentration measuring device 13 viewed from the upper surface. FIG. 11 illustrates the resonator 24, the reflection unit 25, the ultrasonic detection unit 26, the container 27, the window 27b, the pulsed light 41, the photoacoustic signal 42, and the subject 90. The subject 90 is a human finger. The component concentration measuring device 13 will be described with respect to parts different from the component concentration measuring device 12 described with reference to FIGS.

  At least a part of the reflecting portion 25 has a parabolic curved plate shape. Moreover, the reflection part 25 is fixed to the both side surfaces of the container 27 so that the axes passing through the respective focal points coincide and the inner surfaces face each other. Since at least a part is a parabolic curved plate shape, the reflecting portion 25 has one focal point. Note that the ultrasonic detector 26 may be disposed at the focal point of any of the two reflecting units 25, and the subject 90 may be disposed at the focal point of the remaining reflecting units 25.

  The resonator 24 may have a cylindrical shape similar to that shown in FIGS.

  The point that the photoacoustic signal detection accuracy of the component concentration measurement device 13 is high will be described. As in the component concentration measuring apparatus 12 of FIGS. 8 and 9, the subject 90 is irradiated with the pulsed light 41, the subject 90 emits the photoacoustic signal 42 in all directions, and the resonator 24 resonates. Then, the amplitude of the photoacoustic signal 42 is amplified. In addition, at least a part of the reflecting portion 25 is a parabolic curved plate, and the inner surfaces face each other so that the axes passing through the respective focal points coincide with each other, so that one reflecting portion 25 has a photoacoustic signal whose amplitude is amplified. 42 is efficiently reflected to the ultrasonic detection unit 26 disposed at the focal point of the other reflection unit 25. Similar to the component concentration measurement apparatus 12 of FIGS. 8 and 9, the amplitude of the photoacoustic signal 42 is amplified, and the reflection unit 25 efficiently reflects the photoacoustic signal 42 to the ultrasonic detection unit 26, thereby detecting ultrasonic waves. The unit 26 has high detection accuracy. Therefore, it is possible to provide a component concentration measuring apparatus with high photoacoustic signal detection accuracy.

  The component concentration measuring apparatus of the present invention can be used not only for medical diagnosis but also for daily health management and cosmetic diagnosis.

1 is a schematic diagram of a component concentration measuring apparatus according to a first embodiment of the present application. It is the perspective view which looked at the component concentration measuring apparatus of FIG. 1 from the upper surface. It is the enlarged view seen from the upper surface and side surface of the resonator of FIG. It is an enlarged view of the cross section of a reflection part. It is the schematic of the component concentration measuring apparatus which concerns on 2nd Embodiment of this application. It is the perspective view which looked at the component concentration measuring apparatus of FIG. 5 from the upper surface. It is the enlarged view seen from the upper surface and side surface of the resonator of FIG. It is the schematic of the component concentration measuring apparatus which concerns on 3rd Embodiment of this application. It is the perspective view which looked at the component concentration measuring apparatus of FIG. 8 from the upper surface. It is the schematic of the component concentration measuring apparatus which concerns on 4th Embodiment of this application. It is the perspective view which looked at the component concentration measuring apparatus of FIG. 10 from the upper surface. It is sectional drawing of the conventional biological imaging apparatus. It is a top view of the conventional biological imaging apparatus.

10, 11, 12, 13 Component concentration measuring device 21 Light generation unit 22 Light pulse modulation unit 23 Light irradiation unit 24 Resonator 24a Support column 25 Reflection unit
26 Ultrasonic Detection Unit 27 Container 27a Insertion Port 27b Window 27c Door 28 Optical Fiber 29 Support 30 Preamplifier 31 Signal Processing Unit 33 High Acoustic Impedance Layer 34 Low Acoustic Impedance Layer 41 Pulsed Light 42 Photoacoustic Signal 90 Subject DESCRIPTION OF SYMBOLS 100 Living body imaging apparatus 101 Subject 111 Water tank 112 Water 121 Pulse light source 122 Concave mirror 123 Lens 124 Ultrasonic wave detection part 125 Signal processing part 128 Step motor 130 Rotation orbit

Claims (7)

A light generating section for generating light;
An optical pulse modulation unit that pulse-modulates the light generated by the light generation unit and outputs pulsed light; and
A light irradiation unit that irradiates a subject with the pulsed light output by the light pulse modulation unit;
A spherical or cylindrical resonator that resonates with a photoacoustic signal emitted from the subject by the pulsed light;
Reflecting the photoacoustic signal radiated from the subject, at least a part of which is an ellipsoidal surface,
An ultrasonic detection unit that detects the photoacoustic signal reflected by the reflection unit or radiated from the subject, and disposed at a first focal point of the reflection unit;
Component concentration measurement comprising: a container having at least the resonator, the reflection unit, and the ultrasonic detection unit, and having an insertion port for inserting the subject and placing the subject at a second focal point of the reflection unit A device,
The component concentration measuring apparatus according to claim 1, wherein the resonator is arranged inside the reflecting unit so as to surround the subject arranged at the second focal point of the reflecting unit. A light generating section for generating light;
An optical pulse modulation unit that pulse-modulates the light generated by the light generation unit and outputs pulsed light; and
A light irradiation unit that irradiates a subject with the pulsed light output by the light pulse modulation unit;
A spherical or cylindrical resonator that resonates with a photoacoustic signal emitted from the subject by the pulsed light;
Reflecting the photoacoustic signal radiated from the subject, at least a part of which is an elliptical cylinder,
An ultrasonic detection unit that detects the photoacoustic signal reflected by the reflection unit or radiated from the subject, and disposed at a first focal point of the reflection unit;
Component concentration measurement comprising: a container having at least the resonator, the reflection unit, and the ultrasonic detection unit, and having an insertion port for inserting the subject and placing the subject at a second focal point of the reflection unit A device,
The component concentration measuring apparatus according to claim 1, wherein the resonator is arranged inside the reflecting unit so as to surround the subject arranged at the second focal point of the reflecting unit. A light generating section for generating light;
An optical pulse modulation unit that pulse-modulates the light generated by the light generation unit and outputs pulsed light; and
A light irradiation unit that irradiates a subject with the pulsed light output by the light pulse modulation unit;
A spherical or cylindrical resonator that resonates with a photoacoustic signal emitted from the subject by the pulsed light;
Two reflecting portions that reflect the photoacoustic signal radiated from the subject, at least part of which is a paraboloid, and whose inner surfaces face each other so that axes passing through the respective focal points coincide with each other;
An ultrasonic detection unit that detects the photoacoustic signal reflected by the reflection unit or radiated from the subject, and disposed at a focal point of the reflection unit;
A component including at least the resonator, the two reflection units, and the ultrasonic detection unit, and a container having an insertion port for inserting the subject and placing the subject at a focal point of the other reflection unit. A concentration measuring device comprising:
The component concentration measuring apparatus, wherein the resonator is disposed on the inner surface side of the other reflecting portion so as to surround the subject to be disposed at a focal point of the other reflecting portion. A light generating section for generating light;
An optical pulse modulation unit that pulse-modulates the light generated by the light generation unit and outputs pulsed light; and
A light irradiation unit that irradiates a subject with the pulsed light output by the light pulse modulation unit;
A spherical or cylindrical resonator that resonates with a photoacoustic signal emitted from the subject by the pulsed light;
Two reflecting portions that reflect the photoacoustic signal radiated from the subject, at least a part of which is a parabolic curved plate, and whose inner surfaces face each other so that axes passing through respective focal points coincide with each other;
An ultrasonic detection unit that detects the photoacoustic signal reflected by the reflection unit or radiated from the subject, and disposed at a focal point of the reflection unit;
A component including at least the resonator, the two reflection units, and the ultrasonic detection unit, and a container having an insertion port for inserting the subject and placing the subject at a focal point of the other reflection unit. A concentration measuring device comprising:
The component concentration measuring apparatus, wherein the resonator is disposed on the inner surface side of the other reflecting portion so as to surround the subject to be disposed at a focal point of the other reflecting portion.   The container is filled with a liquid having an acoustic impedance substantially equal to that of the subject, and the resonator has a radius of k / 2 times the wavelength of the photoacoustic signal propagating in the liquid. The component concentration measuring apparatus according to any one of claims 1 to 4, wherein k is an integer of 1 or more.   The high acoustic impedance layer has a thickness of m / 4 times the wavelength of the photoacoustic signal propagating through the high acoustic impedance layer, and the low acoustic impedance layer propagates through the low acoustic impedance layer. The thickness is n / 4 times the wavelength of a photoacoustic signal, and at least a part of the reflective portion is formed by alternately stacking the high acoustic impedance layer and the low acoustic impedance layer. The component concentration measuring apparatus according to any one of 1 to 5 (m and n are odd numbers of 1 or more). The high acoustic impedance layer has a thickness p / 4 times the wavelength of the photoacoustic signal propagating through the high acoustic impedance layer, and the low acoustic impedance layer propagates through the low acoustic impedance layer. The thickness of the resonator is q / 4 times the wavelength of the photoacoustic signal, and at least a part of the resonator is formed by alternately stacking the high acoustic impedance layer and the low acoustic impedance layer. The component concentration measuring apparatus according to any one of 1 to 6 (p and q are odd numbers of 1 or more).

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