Photoacoustic diagnostic device and method

Abstract

The present invention relates to a photoacoustic diagnostic device and method for measuring blood glucose in blood by measuring changes in the shape of a membrane caused by sound waves, and more particularly to a photoacoustic diagnostic device and method for adjusting the frequency response of a diagnostic device by adjusting the size of a membrane. The photoacoustic diagnostic device according to one embodiment of the present invention includes a light source that irradiates a subject with light and emits sound, a plurality of sound receiving units each equipped with a membrane whose shape changes in response to the sound, and a measuring unit that measures the changes in the shape of the membrane, and the membranes of the plurality of sound receiving units may have different sizes.

Description

[Technical field]

[0001] The present invention relates to a photoacoustic diagnostic device and method for measuring blood glucose in blood by measuring morphological changes in a membrane caused by acoustic waves, and more particularly to a photoacoustic diagnostic device and method for adjusting the frequency response of the diagnostic device by adjusting the size of the membrane. [Background technology]

[0002] Photoacoustic diagnostic technology is a technology that uses the photoacoustic effect to non-invasively shape biological tissue. When a short electromagnetic pulse of a laser is incident on biological tissue for photoacoustic diagnosis, part of the energy is absorbed by the tissue and converted into heat, causing instantaneous thermoelastic expansion. As a result, ultrasonic waves with a wide frequency range are emitted, which can be detected by ultrasonic transducers from various directions and converted into images.

[0003] Photoacoustic diagnostic technology has the advantage of being able to combine the characteristics of optical imaging and ultrasound imaging, since it converts electromagnetic waves into ultrasound and detects them. The contrast of purely optical imaging methods is much higher than that of ultrasound imaging, but it has the disadvantage that it can only image up to a certain depth from the surface of the body due to high light scattering in soft tissue. In contrast, ultrasound imaging has high enough spatial resolution to be used for fetal testing. Photoacoustic imaging overcomes the disadvantage of optical imaging, which is the low imaging depth, by converting ultrasound using the photoacoustic effect, and can simultaneously achieve high optical contrast and high spatial resolution.

[0004] The equipment that realizes photoacoustic diagnostic technology is broadly composed of an optical section that irradiates a laser and a transducer that measures ultrasound. There are two types of transducers that measure ultrasound: piezo type and MEMS (Micro Electro Mechanical Systems) type. In the piezo type, an electric potential is formed in a piezoelectric material due to pressure caused by ultrasound, and the ultrasound is measured by measuring the voltage, which is the potential difference. In the MEMS type, the shape of a membrane changes due to pressure caused by ultrasound, and the ultrasound is measured by measuring the change in capacitance caused by the change in shape.

[0005] Since the above-mentioned transducer is configured as a module separate from the optical unit, it is difficult to reduce the size of a photoacoustic diagnostic apparatus having the above-mentioned transducer, which reduces the convenience of use. Summary of the Invention [Problem to be solved by the invention]

[0006] In order to solve the above-mentioned problems, the present invention aims to provide a photoacoustic diagnostic device and method in which the resonant frequency of the transducer is adjusted by adjusting the size of the membrane to match the blood glucose photoacoustic peak. [Means for solving the problem]

[0007] As an embodiment of the present invention, a photoacoustic diagnostic apparatus is provided.

[0008] A photoacoustic diagnostic device according to an embodiment of the present invention includes a light source that irradiates light onto a subject to emit sound, a plurality of sound receiving units having membranes whose shape changes in response to the sound, and a measurement unit that measures the change in shape of the membranes, and the membranes of the plurality of sound receiving units may have different sizes.

[0009] In a photoacoustic diagnostic apparatus according to an embodiment of the present invention, each resonance frequency of the sound receiving unit is matched to a photoacoustic peak of blood glucose.

[0010] As an embodiment of the present invention, a photoacoustic diagnostic method is provided.

[0011] A photoacoustic diagnostic method according to one embodiment of the present invention may include a light irradiation step of irradiating light onto a subject using a light source, a sound receiving step of receiving sound radiated from the subject by a plurality of sound receiving units equipped with membranes, a measurement step of measuring a morphological change of the membrane, and a blood glucose analysis step of analyzing the morphological change of the membrane to analyze the presence and amount of blood glucose contained in the blood.

[0012] The photoacoustic diagnostic method according to an embodiment of the present invention may further include a step of adjusting a size of a membrane of the sound receiving unit to match each resonance frequency of the sound receiving unit to a photoacoustic peak of blood glucose.

[0013] As one embodiment of the present invention, a computer-readable recording medium having a program recorded thereon for implementing the above-described method is provided. Effect of the Invention

[0014] The photoacoustic diagnostic apparatus according to the present invention has an advantage that the frequency response of the photoacoustic diagnostic apparatus can be improved by adjusting the resonance frequency of the transducer by adjusting the size of the membrane.

[0015] The effects obtained from the present disclosure are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by a person having ordinary skill in the art to which the present disclosure pertains from the following description. [Brief description of the drawings]

[0016] [Figure 1] 1 is a diagram showing the overall configuration of a photoacoustic diagnostic apparatus according to an embodiment of the present invention. [Diagram 2] 1 is a block diagram of a photoacoustic diagnostic apparatus according to an embodiment of the present invention. [Diagram 3] 2 shows an embodiment of a sound receiving section in a photoacoustic diagnostic apparatus according to the present invention. [Figure 4] 4 shows a frequency response of a sound receiving unit of a photoacoustic diagnostic apparatus according to an embodiment of the present invention. [Diagram 5] 1 is a graph showing an example of a photoacoustic signal due to blood sugar. [Figure 6] 1 is a flowchart of a photoacoustic diagnostic method according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] As an embodiment of the present invention, a photoacoustic diagnostic apparatus is provided.

[0018] A photoacoustic diagnostic device according to an embodiment of the present invention includes a light source that irradiates light onto a subject to emit sound, a plurality of sound receiving units having membranes whose shape changes in response to the sound, and a measurement unit that measures the change in shape of the membranes, and the membranes of the plurality of sound receiving units may have different sizes.

[0019] In a photoacoustic diagnostic apparatus according to an embodiment of the present invention, each resonance frequency of the sound receiving unit is matched to a photoacoustic peak of blood glucose.

[0020] As an embodiment of the present invention, a photoacoustic diagnostic method is provided.

[0021] A photoacoustic diagnostic method according to one embodiment of the present invention may include a light irradiation step of irradiating light onto a subject using a light source, a sound receiving step of receiving sound radiated from the subject by a plurality of sound receiving units equipped with membranes, a measurement step of measuring a morphological change of the membrane, and a blood glucose analysis step of analyzing the morphological change of the membrane to analyze the presence and amount of blood glucose contained in the blood.

[0022] The photoacoustic diagnostic method according to an embodiment of the present invention may further include a step of adjusting a size of a membrane of the sound receiving unit to match each resonance frequency of the sound receiving unit to a photoacoustic peak of blood glucose.

[0023] As one embodiment of the present invention, a computer-readable recording medium having a program recorded thereon for implementing the above-described method is provided.

[0024] Hereinafter, the embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. However, the present invention may be realized in various different forms and is not limited to the embodiments described herein. In the drawings, parts that are not related to the description are omitted in order to clearly explain the present invention, and similar parts are designated by similar reference numerals throughout the specification.

[0025] The terms used in this specification will be briefly explained and the present invention will be specifically described.

[0026] The terms used in the present invention are selected from currently widely used general terms as much as possible while considering the functions in the present invention, but this may vary depending on the intentions or precedents of the engineers in the field, the emergence of new technologies, etc. In addition, in certain cases, the applicant may arbitrarily select terms, and in this case, the meanings of the terms will be described in detail in the description of the invention. Therefore, the terms used in the present invention must be defined based on the meanings of the terms and the overall content of the present invention, rather than simply the names of the terms.

[0027] Throughout the specification, when a part "includes" a certain component, this means that it can further include other components, not excluding other components, unless otherwise specified. Furthermore, terms such as "~ unit" and "module" used in the specification mean a unit that processes at least one function or operation, which is realized by hardware or software, or a combination of hardware and software. Furthermore, throughout the specification, when a part is "connected" to another part, this includes not only "directly connected" but also "connected with other elements between them."

[0028] The present invention will now be described in detail with reference to the accompanying drawings.

[0029] FIG. 1 is a diagram showing the overall configuration of a photoacoustic diagnostic apparatus according to an embodiment of the present invention, and FIG. 2 is a block diagram of the photoacoustic diagnostic apparatus according to the embodiment of the present invention.

[0030] 1 and 2, a photoacoustic diagnostic device according to an embodiment of the present invention may include a light source 100 that irradiates light to a subject and emits sound, a plurality of sound receiving units 200 having membranes whose shape changes in response to the sound, and a measurement unit 300 that measures the change in shape of the membranes, and the membranes of the plurality of sound receiving units 200 may have different sizes.

[0031] The light source 100 can output a laser light, which may be infrared.

[0032] The laser output from the light source 100 is irradiated onto an object to vibrate molecules contained in the object, and ultrasonic waves are emitted due to the vibration of the molecules.

[0033] The photoacoustic diagnostic device may include a plurality of sound receiving units 200, and the membranes included in each sound receiving unit 200 may be formed to have different sizes, so that the resonance frequency (RF) of each sound receiving unit 200 may be set in various ways.

[0034] That is, the photoacoustic diagnostic apparatus according to the present invention includes a plurality of sound receiving units 200 having different sizes, and thus can have a plurality of resonant frequencies, which can be used to measure photoacoustic signals caused by blood sugar.

[0035] The measuring unit 300 can measure the change in the shape of the membrane by measuring the capacitance, and can use an optical method to measure the change in the shape of the membrane by irradiating a light source onto the sound receiving unit 200 and measuring and analyzing the reflected light.

[0036] FIG. 3 shows an embodiment of a sound receiving section in a photoacoustic diagnostic apparatus according to the present invention.

[0037] 3, the sound receiving unit 200 may further include a membrane for detecting sound and a protection unit for protecting the membrane. In the photoacoustic diagnostic device according to the present invention, the sound may correspond to ultrasound.

[0038] The membrane can vibrate in the vertical direction (Y) in response to the applied sound (X). The amplitude of the membrane's vertical vibration varies depending on the intensity of the sound (X). For example, the greater the intensity of the sound (X), the greater the amplitude of the membrane's vertical vibration.

[0039] The membrane can detect the intensity of an externally applied sound (X) and is made of a thin membrane so that it can vibrate with as large an amplitude as possible in response to the externally applied sound (X).

[0040] Membranes are made of the following materials that are primarily used in MEMS processes: single crystal silicon, polycrystalline silicon, silicon nitride, silicon oxide, aluminum and other metal thin film materials, carbon or compounds containing carbon, and stacks of the above materials.

[0041] The protective portion is preferably made of a material having a structure that protects the membrane from external impact while not impeding the transmission of sound to the membrane. For example, a mesh material having a net structure may be used.

[0042] FIG. 4 shows the frequency response of the sound receiving section of a photoacoustic diagnostic apparatus according to one embodiment of the present invention.

[0043] 4, the frequency response of one sound receiving unit 200 can be known. In Fig. 4, the horizontal axis is frequency (Hz) and the vertical axis is amplitude (dB). The resonant frequency means a frequency that has a significantly larger amplitude than other frequencies, and in Fig. 4, A corresponds to the resonant frequency.

[0044] The sound receiving unit 200 may include one membrane, and one membrane has one resonant frequency. For example, if the photoacoustic diagnostic device includes six sound receiving units 200, six membranes may be included and six resonant frequencies should be present.

[0045] A photoacoustic diagnostic apparatus according to an embodiment of the present invention may include six sound receiving units 200, and the resonant frequency of each sound receiving unit 200 is matched to the photoacoustic peak of blood glucose.

[0046] FIG. 5 is a graph showing an example of a photoacoustic signal due to blood sugar.

[0047] In FIG. 5, the horizontal axis is frequency (Hz) and the vertical axis is power spectral density (W / Hz).

[0048] Referring to FIG. 5, a photoacoustic signal may have six peaks, and the frequencies and shapes of the peaks vary depending on the measurement conditions.

[0049] That is, when blood is irradiated with a laser, a desired number of peaks can be selected from the main peaks detected, and the resonant frequency of the sound receiving unit can be matched. The larger the amplitude of the peaks measured at the matched resonant frequency, the greater the amount of blood glucose.

[0050] The photoacoustic diagnostic device according to the present invention includes a plurality of sound receiving units 200, and by matching the resonant frequency of each sound receiving unit 200 to the frequency of the blood glucose peak, even a small signal due to low concentrations of blood glucose or blood glucose in blood vessels far from the skin can be measured by the sound receiving unit that shows a large amplitude, thereby enabling the amount of blood glucose in the blood to be measured precisely.

[0051] FIG. 6 is a flowchart of a photoacoustic diagnostic method according to an embodiment of the present invention.

[0052] Referring to FIG. 6, a photoacoustic diagnostic method according to an embodiment of the present invention is a photoacoustic diagnostic method for measuring blood glucose using a photoacoustic diagnostic device, and includes a light irradiation step S100 of irradiating light onto a subject using a light source 100, a sound receiving step S200 of receiving sound radiated from the subject by a plurality of sound receiving units 200 equipped with membranes, a measurement step S300 of measuring a morphological change of the membrane, and a blood glucose analysis step S400 of analyzing the measured morphological change to analyze the presence and amount of blood glucose contained in the blood.

[0053] The photoacoustic diagnosis method according to an embodiment of the present invention may further include a step S110 of adjusting a size of a membrane of the sound receiving unit 200 to match each resonance frequency of the sound receiving unit 200 to a photoacoustic peak of blood glucose.

[0054] The above-mentioned content relating to the apparatus can be applied to the method according to an embodiment of the present invention, and therefore, the same content as the above-mentioned content relating to the apparatus will not be described in detail.

[0055] The above description of the present invention is for illustrative purposes only, and those skilled in the art will understand that the present invention can be easily modified into other specific forms without changing the technical idea or essential features of the present invention. Therefore, it should be understood that the above-described embodiments are illustrative in all respects and are not limiting. For example, each component described as a single component may be implemented in a distributed form, and similarly, each component described as a distributed form may be implemented in a combined form.

[0056] The scope of the present invention is indicated by the claims set forth below rather than by the above detailed description, and all modifications and variations that fall within the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention.

[0057] 100 light sources 200 Sound receiver 300 Measuring part

Claims

1. A light source that irradiates light onto the subject and causes the subject to emit sound; A plurality of sound receiving units each having a membrane whose shape changes in response to the sound; A measurement unit for measuring a morphological change of the membrane, The membranes of the plurality of sound receiving units have sizes different from each other.

2. The photoacoustic diagnostic apparatus according to claim 1 , wherein each resonance frequency of the sound receiving unit is matched to a photoacoustic peak of blood glucose.

3. 1. A photoacoustic analysis method for measuring blood glucose using a photoacoustic diagnostic apparatus, comprising: a light irradiation step of irradiating the subject with light using a light source; a sound receiving step of receiving the sound radiated from the subject by a plurality of sound receiving units each having a membrane; A measuring step of measuring a morphological change of the membrane; A blood glucose analysis step of analyzing the morphological change of the membrane to analyze the presence and amount of blood glucose contained in the blood, A photoacoustic analysis method, wherein the membranes of the multiple sound receiving parts have different sizes from each other.

4. The photoacoustic analysis method according to claim 3 , further comprising a step of adjusting a size of a membrane of the sound receiving portion to match each resonance frequency of the sound receiving portion to a photoacoustic peak of blood glucose.

5. A computer-readable recording medium having a program recorded thereon for implementing the method according to any one of claims 3 and 4.

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