Photoacoustic measurement device with optimized optical path and non-invasive blood glucose measurement device using same

Abstract

The present disclosure provides a miniaturized photoacoustic measurement device. The photoacoustic measurement device may comprise: a light source for emitting light; an optical element arranged to condense light into a photoacoustic generation area on the surface of an inspection specimen or inside the inspection specimen; an ultrasonic sensor acoustically in contact with the inspection specimen so as to detect photoacoustic waves from the photoacoustic generation area and output photoacoustic detection signals; a sensor accommodation unit for accommodating the ultrasonic sensor and providing an acoustically opened measurement opening in contact with the inspection specimen; and an optical path unit for providing an optical path space so that light that has passed through the optical element is incident into the inspection specimen from the optical opening opposite to the inspection specimen. The light emitted from the light source of the photoacoustic measurement device has a high-speed axis and a low-speed axis on a cross section, and a straight line between the center of the measurement opening and the central axis of the optical path in the optical path space is aligned with the low-speed axis of the light.

Description

Photoacoustic measuring device with an optimized optical path and non-invasive blood glucose measuring device using the same

[0001] The present disclosure relates to a photoacoustic measuring device capable of obtaining information regarding components within a sample using photoacoustic phenomena. More specifically, the present disclosure relates to a photoacoustic measuring device having a form factor in which the optical path is optimized.

[0002] Photoacoustic phenomena are events in which a material generates sound when illuminated by light, as it absorbs the light, heats up locally, and undergoes expansion and contraction. The sound waves or ultrasound generated by photoacoustic phenomena can be measured by acoustic sensors and utilized to visualize the internal structure of a material or analyze the components within a sample.

[0003] Meanwhile, blood glucose measurement is crucial in diabetes management. Although blood sampling is the most accurate method, undergoing repeated daily blood draws is quite painful for diabetic patients. Consequently, technologies for non-invasive blood glucose measurement without blood sampling have been developed, and photoacoustic-based non-invasive blood glucose measurement technology is one such example.

[0004] Photoacoustic signals measured with glucose solutions at the laboratory level exhibit characteristic changes depending on glucose concentration, and theoretically, the glucose concentration in the solution can be estimated from the pattern of such changes. However, in practice, when measuring photoacoustic signals on human tissues such as skin, it is not easy to identify changes in blood glucose concentration from the measured photoacoustic signals.

[0005] The technical problem of the present disclosure is to provide a photoacoustic measuring device capable of obtaining more accurate information regarding components within a sample using photoacoustics.

[0006] The technical problem of the present disclosure is to provide a photoacoustic measuring device that maximizes photoacoustic detection performance with a miniaturized form factor and an optimized optical path.

[0007] The technical problems of the present disclosure are not limited to those mentioned above, and other unmentioned technical problems will be clearly understood by a person skilled in the art from the description below.

[0008] The means for solving the problem are provided to introduce, in a simplified form, some concepts that are described in more detail in the detailed description of the present disclosure, and are not intended to identify the essential concepts of the present disclosure or to determine the scope of the present disclosure.

[0009] A photoacoustic measuring device according to one aspect of the present disclosure comprises a light source emitting light, an optical element disposed to concentrate the light into a photoacoustic generating region on the surface or inside of an irradiated sample, an ultrasonic sensor that acoustically contacts the irradiated sample and detects photoacoustics from the photoacoustic generating region and outputs a photoacoustic detection signal, a sensor receiving portion that accommodates the ultrasonic sensor and provides a measuring aperture that is acoustically open in contact with the irradiated sample, and an optical path portion that provides an optical path space so that light passing through the optical element is incident into the irradiated sample from an optical aperture facing the irradiated sample, wherein the light emitted by the light source has a high-speed axis and a low-speed axis in cross-section, and a straight line between the center of the measuring aperture and the center axis of the optical path in the optical path space can be aligned with the low-speed axis of the light.

[0010] According to an embodiment, the cross-section of the optical path space has a major axis aligned with the high-speed axis of the optical cross-section and a minor axis aligned with the low-speed axis of the optical cross-section, and the distance between the center of the measuring aperture and the center of the optical aperture may be the sum of the distance from the center of the measuring aperture to the edge, the minimum design thickness of the partition between the measuring aperture and the optical aperture, and the length of the minor axis of the optical aperture.

[0011] According to an embodiment, the thickness of the partition between the sensor receiving space and the optical path space may be 0 in at least some sections between the sensor receiving space and the optical path space.

[0012] According to an embodiment, the cross-sectional area of ​​the optical path space can be monotonically reduced along the direction of travel of the optical path.

[0013] According to an embodiment, the ultrasonic sensor has an acoustic axis, and the acoustic axis of the ultrasonic sensor may be positioned so as to intersect the center axis of the optical path within the optical path space within the irradiated sample.

[0014] According to an embodiment, the sensor receiving portion and the optical path portion may be integrated.

[0015] According to an embodiment, the photoacoustic measuring device may further include a light source driving unit that drives a light source to emit light having a predetermined energy and pulse width, and an analysis unit that analyzes characteristics within an irradiated sample from a photoacoustic detection signal output by an ultrasonic sensor.

[0016] According to the embodiments, the measurement data may include quantitative or qualitative information regarding specific material components within the investigated sample.

[0017] According to the embodiment, the measurement data may include information regarding the concentration of glucose in the dermis layer of the skin or in the blood vessels.

[0018] According to the photoacoustic measuring device according to the technical concept of the present disclosure, information regarding components within a sample can be obtained more accurately by using photoacoustics.

[0019] According to the photoacoustic measuring device according to the technical concept of the present disclosure, photoacoustic detection performance can be maximized with a miniaturized form factor and an optimized optical path.

[0020] The effects obtainable from the exemplary embodiments of the present disclosure are not limited to those mentioned above, and other unmentioned effects can be clearly derived and understood by those skilled in the art from the description of the exemplary embodiments of the present disclosure below. That is, unintended effects resulting from the implementation of the exemplary embodiments of the present disclosure can also be derived by those skilled in the art from the exemplary embodiments of the present disclosure.

[0021] The embodiments, aspects, advantages, and other features of the present disclosure will be better understood by reading the following detailed description with reference to the accompanying drawings, in which the same letters in the drawings indicate the same parts throughout the drawings.

[0022] FIG. 1 is a schematic projection illustrating a photoacoustic measuring device according to embodiments.

[0023] FIG. 2 is a schematic block diagram illustrating a photoacoustic measuring device according to embodiments.

[0024] FIGS. 3 to 7 are drawings illustrating the arrangement relationship between the optical path space and the ultrasonic sensor receiving space of a photoacoustic measuring device according to embodiments.

[0025] For example, some components of the device in the drawings may be represented by conventional symbols. The drawings may primarily depict specific details relevant to understanding the embodiments of the present disclosure, and details that are readily understood by a person skilled in the art may be omitted or simplified to maintain the visibility of the drawings. Some components of the drawings may not be drawn to their actual proportions for the sake of simplification or convenience of explanation.

[0026] The terms used in the embodiments have been selected to be as widely used as possible in consideration of the context of this disclosure; however, these may vary depending on the intent of those skilled in the art, case law, the emergence of new technologies, etc. Additionally, in specific cases where the applicant has arbitrarily selected a term, its meaning will be described in detail in the relevant description. Therefore, terms used in this disclosure should be defined not merely by their names, but based on their meanings and the overall context of this disclosure.

[0027] Singular expressions may include plural expressions unless the context clearly indicates otherwise. Terms used herein, including technical or scientific terms, may have the same meaning as generally understood by those skilled in the art as described in this disclosure.

[0028] When a part of a specification is described as "including" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components. Furthermore, terms such as "part" or "module" as used in the specification refer to a unit that processes at least one function or operation, and this may be implemented in hardware or software, or as a combination of hardware and software.

[0029] Throughout this specification, terms such as acoustics, acoustic waves, sound waves, sound, sound pressure, pressure waves, elastic waves, noise, mechanical vibration, etc. relate to waves that propagate within a specimen accompanied by positional changes of particles of a medium in air or within a solid to semi-solid, liquid, or organic tissue specimen, depending on the context.

[0030] Hereinafter, embodiments will be described in detail with reference to the drawings.

[0031] FIG. 1 is a schematic projection illustrating a photoacoustic measuring device according to embodiments, and FIG. 2 is a schematic block diagram illustrating a photoacoustic measuring device according to embodiments.

[0032] Referring to FIG. 1 and FIG. 2 together, the photoacoustic measuring device (1) may include a light source housing (10), a light source (11), an optical element (12), a light source driving unit (20), a light path unit (30), an optical aperture (31), a light path space (32), a sensor receiving unit (40), a measuring aperture (41), a sensor receiving space (42), an ultrasonic sensor (43), a sampling unit (50), a memory (60), and an analysis unit (70).

[0033] According to an embodiment, the light source (11) may be a light-emitting diode (LED) or a laser diode (LD) that directly generates light. According to an embodiment, the light source housing (10) may contain the light source (11) inside. According to an embodiment, the light source housing (10) may also contain a light source driving unit (20) for driving the light source (11). The light source driving unit (20) may drive the light source (11) by supplying power to the light source (11) with a predetermined light output and light emission time.

[0034] One or more optical elements (12) are optical devices necessary for inducing light generated by a light source (11) and controlling optical properties, and are, for example, one or more combinations of optical elements such as a lens, a zoom lens, a reflective mirror, a dichroic mirror, a beam splitter, a prism, an optical fiber, a grating, a polarizer, etc., and are not limited to the elements listed herein.

[0035] According to an embodiment, the light source housing (10) may contain one or more optical elements (12). According to an embodiment, the light source housing (10) may contain a light source (11) and one or more optical elements (12), while not containing a light source driving unit (21).

[0036] The optical path section (30) can guide a beam of light (15) transmitted through an opening of the light source housing (10) and emit it through an optical opening (31) that is open toward an irradiated sample (90). The optical path space (32) within the optical path section (30) is preferably optically transparent but does not necessarily have to be an empty space and may be, for example, an optical guide made of optical glass material.

[0037] The sensor receiving portion (40) has a measurement opening (41) that is acoustically open toward the investigation sample (90) and can receive and fix an ultrasonic sensor (43) in an internal sensor receiving space (42). The ultrasonic sensor (43) can detect photoacoustics transmitted from the investigation sample (90) by acoustically contacting the investigation sample (90) through the measurement opening (41) on its measurement surface. According to an embodiment, the sensor receiving portion (40) can embed or receive and fix most of the body of the ultrasonic sensor (43) in the sensor receiving space (42), excluding the measurement surface of the ultrasonic sensor (43). According to an embodiment, even if most of the body of the ultrasonic sensor (43) is not received in the sensor receiving space (42), the sensor receiving portion (40) can be fixed so that the ultrasonic sensor (43) is at least kept separated from the light source housing (10) without direct acoustic contact, and furthermore, so that the ultrasonic sensor (43) does not deviate from the measurement position on the investigation sample (90) during measurement.

[0038] According to an embodiment, the photoacoustic measuring device (1) may include a sampling unit (50) that generates sampling data by sampling a photoacoustic signal detected by an ultrasonic sensor (43), a memory (60) that stores the sampling data, and an analysis unit (70) that analyzes the sampling data. According to an embodiment, the irradiated sample is skin, and the measurement data may include quantitative or qualitative information regarding the components of a specific substance within the dermis layer of the skin, for example, concentration information. The analysis unit (70) may be implemented, for example, by a processor, a Neural Processing Unit (NPU), etc. Various electronic circuit elements, including the light source driving unit (20), the sampling unit (50), the memory (60), and the analysis unit (70), may be implemented on an embedded circuit board (80).

[0039] According to an embodiment, the photoacoustic measuring device (1) can measure quantitative or qualitative information of a specific substance in the dermis layer, such as glucose concentration, oxygen saturation, glycated hemoglobin concentration, etc. by irradiating the skin with laser pulses of a predetermined wavelength, and measuring the generated ultrasonic sound.

[0040] Since photoacoustic signals are essentially acoustic waves, they can be considered to decrease inversely proportional to distance or inversely proportional to the square of the distance, although this depends on the measurement location and the relative geometry of the photoacoustic source (PA source).

[0041] Therefore, the geometry between the measurement location and the photoacoustic source, and the distance (D) between the center of the optical aperture (31) of the optical path section (30) and the center of the measurement aperture (41) of the sensor receiving section (40) can play a significant role in the performance of the photoacoustic measuring device (1).

[0042] Accordingly, the present disclosure discusses methods to optimize the incidence of a beam (15) so that the attenuation of photoacoustics observed at the location of the ultrasonic sensor in the photoacoustic measuring device (1) is minimized, and to reduce or optimize the distance (D) between the center of the optical aperture (31) and the measuring aperture (41).

[0043] FIGS. 3 to 7 are drawings illustrating the arrangement relationship between the optical path space and the sensor receiving space of a photoacoustic measuring device according to embodiments. In each of FIGS. 3 to 7, (a) is a drawing depicting the optical path space (32) and the sensor receiving space (42) of the photoacoustic measuring device (1) in three dimensions, and (b) is a drawing depicting a cross-section of A-A'.

[0044] Referring to FIG. 3, the optical path space (32) and the sensor receiving space (42) of the photoacoustic measuring device (1) are both generally cylindrical, and their respective radii (R1, R2) and cross-sectional areas are generally constant. A beam (15) is incident on the optical path space (32) along the optical axis (Z1) and guided to the optical aperture (31). The beam (15) has a generally circular cross-section and, as it travels along the optical axis (Z1), is focused to resemble an inverted truncated cone overall. The area where the beam (15) does not intersect accounts for a large proportion of the total area of ​​the optical aperture (31).

[0045] The distance (D) between the center (C1) of the optical opening (31) and the center (C2) of the measurement opening (41) can be the sum of the radius (R1) of the optical path space (32), the radius (R2) of the sensor receiving space (42), and the thickness (TH) of the partition wall. According to an embodiment, even if the partition wall between the optical opening (31) and the measurement opening (41) has a minimum thickness, the cross-section of the optical path space (32) may vary along the optical axis (Z1), and the thickness may be substantially zero in some sections between the optical path space (32) and the sensor receiving space (42).

[0046] Referring to FIG. 4, the optical path space (32) and the sensor receiving space (42) of the photoacoustic measuring device (1) are both generally cylindrical, as in FIG. 3, and their respective radii (R1, R2) and cross-sectional areas are generally constant. Overall, the proportion of the space in the optical path space (32) where the beam (15) does not pass is large.

[0047] The cross-section of the beam (15) may be elliptical or rounded rectangular rather than circular, and the short axis of the beam (15) may be called the low-speed axis (SL) and the long axis may be called the high-speed axis (F). The optical axis (Z1) of the beam (15) and the acoustic axis (Z2) of the ultrasonic sensor (43) may be parallel to each other.

[0048] The cross-section of the optical path space (32) may have its major axis (L) aligned with the high-speed axis (F) of the cross-section of the beam (15) and its minor axis (SH) aligned with the low-speed axis (SL) of the cross-section of the beam (15). The distance (D) between the center (C1) of the optical aperture (31) and the center (C2) of the measurement aperture (41) may be the sum of the radius (R1) of the optical path space (32), the radius (R2) of the sensor receiving space (42), and the thickness (TH) of the partition wall. According to an embodiment, even if the partition wall between the optical aperture (31) and the measurement aperture (41) has a minimum thickness, the thickness may be substantially zero in some sections between the optical path space (32) and the sensor receiving space (42).

[0049] A straight line between the optical axis (Z1) of the optical path and the center (C2) of the measurement aperture (41) can be aligned with the low-velocity axis (SL) of the beam (15) cross-section so that the beam (15) is guided to pass through the optical aperture (31). In this case, among the photoacoustics generated when the beam (15) is incident on the irradiated sample (90), the photoacoustics generated along the high-velocity axis (F) of the beam (15) propagate in a radial direction (R) toward the sensor receiving space (42), thereby maximizing the detection of photoacoustics by the ultrasonic sensor (43).

[0050] Referring to FIG. 5, the optical path space (532) of the photoacoustic measuring device (1) is generally cylindrical in shape with an elliptical cross section or a rounded rectangular cross section, and the cross section may have a major axis (L) and a minor axis (SH). Compared to the optical path space (32) of FIG. 4, the optical path space (532) of FIG. 5 is aligned with the outer edge of the cross section of the beam (15) with some margin, and the cross-sectional area may be generally constant. The optical aperture (531) is also generally elliptical or rounded rectangular. The sensor receiving space (42) is generally cylindrical, and the radius (R2) and cross-sectional area of ​​the sensor receiving space (42) are generally constant. Overall, the proportion of the space in the optical path space (532) through which the beam (15) does not pass is smaller than in the case of FIG. 3 or FIG. 4.

[0051] The cross-section of the beam (15) may be elliptical or rounded rectangular rather than circular, and the short axis of the beam (15) may be called the low-speed axis (SL) and the long axis may be called the high-speed axis (F). The optical axis (Z1) of the beam (15) and the acoustic axis (Z2) of the ultrasonic sensor (43) may be parallel to each other.

[0052] The cross-section of the optical path space (532) may have its major axis (L) aligned with the high-speed axis (F) of the cross-section of the beam (15) and its minor axis (SH) aligned with the low-speed axis (SL) of the cross-section of the beam (15). The distance (D) between the center (C1) of the optical aperture (531) and the center (C2) of the measurement aperture (41) may be the sum of the minor axis (SH) of the optical path space (532), the radius (R2) of the sensor receiving space (42), and the thickness (TH) of the partition wall. According to an embodiment, even if the partition wall between the optical aperture (531) and the measurement aperture (41) has thickness, the thickness may be substantially zero in at least some sections between the optical path space (532) and the sensor receiving space (42).

[0053] A straight line between the optical axis (Z1) of the optical path and the center (C2) of the measurement aperture (41) can be aligned with the low-velocity axis (SL) of the beam (15) cross-section so that the beam (15) is guided to pass through the optical aperture (531). In this case, among the photoacoustics generated when the beam (15) is incident on the irradiated sample (90), the photoacoustics generated along the high-velocity axis (F) of the beam (15) propagate in a radial direction (R) toward the sensor receiving space (42), thereby maximizing the detection of photoacoustics by the ultrasonic sensor (43).

[0054] Referring to FIG. 6, the optical path space (632) of the photoacoustic measuring device (1) generally has an elliptical cross section or a rounded rectangular cross section, and the cross section may have a major axis (L) and a minor axis (SH). Compared to the optical path space (532) of FIG. 5, the optical path space (632) of FIG. 6 is aligned with the outer edge of the cross section of the beam (15) with almost no clearance, and the cross-sectional area is generally reduced. The optical aperture (631) is also generally elliptical or rounded rectangular. The sensor receiving space (42) is generally cylindrical, and the radius (R2) and cross-sectional area of ​​the sensor receiving space (42) are generally constant. Overall, the proportion of the space in the optical path space (632) through which the beam (15) does not pass is very small compared to FIG. 3 or FIG. 4, and is also small compared to FIG. 5.

[0055] The cross-section of the beam (15) may be elliptical or rounded rectangular rather than circular, and the short axis of the beam (15) may be called the low-speed axis (SL) and the long axis may be called the high-speed axis (F). The optical axis (Z1) of the beam (15) and the acoustic axis (Z2) of the ultrasonic sensor (43) may be parallel to each other.

[0056] The cross-section of the optical path space (632) may have its major axis (L) aligned with the high-speed axis (F) of the cross-section of the beam (15), and its minor axis (SH) aligned with the low-speed axis (SL) of the cross-section of the beam (15). The distance (D) between the center (C1) of the optical aperture (631) and the center (C2) of the measurement aperture (41) may be the sum of the minor axis (SH) of the optical path space (632), the radius (R2) of the sensor receiving space (42), and the thickness (TH) of the partition wall.

[0057] According to the embodiment, even if the partition between the optical opening (631) and the measuring opening (41) has thickness, the thickness may be substantially zero in at least some sections between the optical path space (632) and the sensor receiving space (42).

[0058] A straight line between the optical axis (Z1) of the optical path and the center (C2) of the measurement aperture (41) can be aligned with the low-velocity axis (SL) of the beam (15) cross-section so that the beam (15) is guided to pass through the optical aperture (631). In this case, among the photoacoustics generated when the beam (15) is incident on the irradiated sample (90), the photoacoustics generated along the high-velocity axis (F) of the beam (15) propagate in a radial direction (R) toward the sensor receiving space (42), thereby maximizing the detection of photoacoustics by the ultrasonic sensor (43).

[0059] Referring to FIG. 7, the optical path space (732) of the photoacoustic measuring device (1) generally has an elliptical cross section or a rounded rectangular cross section, and the cross section may have a major axis (L) and a minor axis (SH). Similar to the optical path space (632) of FIG. 6, the optical path space (732) of FIG. 7 is aligned with the cross-sectional outline of the beam (15) with almost no margin. The optical aperture (731) is also generally elliptical or rounded rectangular.

[0060] The sensor receiving space (42) is generally cylindrical, and the radius (R2) and cross-sectional area of ​​the sensor receiving space (42) are generally constant. Overall, the proportion of the space in the optical path space (32) where the beam (15) does not pass is very small compared to the case of FIG. 3 or FIG. 4, and is also small compared to the case of FIG. 5 or FIG. 6.

[0061] The cross-section of the beam (15) can be described as elliptical or rounded rectangular rather than circular, and the short axis of the beam (15) can be described as the low-speed axis (SL) and the long axis as the high-speed axis (F). In contrast to the optical axis (Z1) of the beam (15) in FIG. 6 and the acoustic axis (Z2) of the ultrasonic sensor (43) being parallel, the optical axis (Z1) of the beam (15) in FIG. 7 is tilted toward the acoustic axis (Z2) of the ultrasonic sensor (43).

[0062] The cross-section of the optical path space (732) may have its major axis (L) aligned with the high-speed axis (F) of the cross-section of the beam (15) and its minor axis (SH) aligned with the low-speed axis (SL) of the cross-section of the beam (15). The distance (D) between the center (C1) of the optical aperture (731) and the center (C2) of the measurement aperture (41) may be the sum of the minor axis (SH) of the optical path space (732) and the radius (R2) of the sensor receiving space (42). The thickness may be substantially zero in the entire section between the optical path space (732) and the sensor receiving space (42).

[0063] A straight line between the optical axis (Z1) and the center (C2) of the measurement aperture (41) can be aligned with the low-velocity axis (SL) of the beam (15) cross-section so that the beam (15) can be guided to pass through the optical aperture (31). In this case, the beam (15) penetrates into the irradiated sample (90) closer to the measurement aperture (41) than in the case of FIG. 6, so the photoacoustic generation area can also be closer to the measurement aperture (41). In addition, among the photoacoustics generated when the beam (15) is incident on the irradiated sample (90), the photoacoustics generated along the high-velocity axis (F) of the beam (15) propagate in the radial direction (R) toward the sensor receiving space (42), thereby maximizing the detection of photoacoustics by the ultrasonic sensor (43).

[0064] As described above, exemplary embodiments have been disclosed in the drawings and specification. Although specific terms have been used to describe the embodiments in this specification, they are used only for the purpose of explaining the technical concept of the present disclosure and are not intended to limit the meaning or the scope of the present disclosure as defined in the claims. Therefore, those skilled in the art will understand that various modifications and equivalent alternative embodiments are possible therefrom.

[0065] Explanation of the symbols

[0066] 1 Photoacoustic measuring device

[0067] 10 light source housing

[0068] 11 light source

[0069] 12 optical elements

[0070] 20 Light source driving unit

[0071] 30 Optical Road Section

[0072] 31 optical aperture

[0073] 32 Optical Road Space

[0074] 40 sensor receiving portion

[0075] 41 measuring opening

[0076] 42 sensor accommodation space

[0077] 43 Ultrasonic sensor

[0078] 50 Sampling Section

[0079] 60 memory

[0080] 70 Analysis Department

[0081] 90 survey samples

Claims

1. A light source that emits light; An optical element positioned to concentrate the light into a photoacoustic generating area on the surface or inside of the investigation sample; An ultrasonic sensor that acoustically contacts the above-mentioned investigation sample, detects photoacoustics from the above-mentioned photoacoustic generation region, and outputs a photoacoustic detection signal; A sensor receiving portion that accommodates the ultrasonic sensor and provides an acoustically open measuring opening in contact with the investigation sample; and A photoacoustic measuring device comprising an optical path section that provides an optical path space such that light passing through the optical element is incident into the irradiated sample through an optical aperture facing the irradiated sample, The light emitted by the above light source has a high-speed axis and a low-speed axis in cross-section, A photoacoustic measuring device characterized in that the straight line between the center of the measuring aperture and the center axis of the optical path within the optical path space is aligned with the low-velocity axis of the light.

2. A photoacoustic measuring device according to claim 1, wherein the cross-section of the optical path space has a major axis aligned with the high-speed axis of the cross-section of the light and a minor axis aligned with the low-speed axis of the cross-section of the light, and the distance between the center of the measuring aperture and the center of the optical aperture is the sum of the distance from the center of the measuring aperture to the edge, the thickness of the partition between the measuring aperture and the optical aperture, and the length of the minor axis of the optical aperture.

3. A photoacoustic measuring device according to claim 2, characterized in that the thickness of the partition between the sensor receiving portion and the optical path portion is 0 in at least a portion of the section between the sensor receiving portion and the optical path portion.

4. A photoacoustic measuring device according to claim 1, characterized in that the cross-sectional area of ​​the optical path space decreases monotonically along the direction of travel of the optical path.

5. A photoacoustic measuring device according to claim 1, wherein the ultrasonic sensor has an acoustic axis, and the acoustic axis of the ultrasonic sensor is arranged to intersect the central axis of the optical path within the optical path space within the irradiated sample.

6. A photoacoustic measuring device according to claim 1, characterized in that the sensor receiving portion and the optical path portion are integrated.

7. In Claim 1, A light source driving unit that drives the light source to emit the light having a predetermined energy and pulse width; and A photoacoustic measuring device characterized by further including an analysis unit that analyzes characteristics within the investigation sample from a photoacoustic detection signal output by the ultrasonic sensor.

8. A photoacoustic measuring device according to claim 7, characterized in that the measurement data includes quantitative or qualitative information regarding a specific substance component within the investigated sample.

9. A photoacoustic measuring device according to claim 7, characterized in that the measurement data includes information regarding the concentration of glucose in the dermal layer of the skin or in the blood vessels.

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