Handheld acousto-optic modulation device and light scattering suppression method

Abstract

The invention discloses a handheld acousto-optic modulation device and a light scattering suppression method. When the handheld acousto-optic modulation device is used, the transparent film bonded on the upper surface is tightly attached to a medium, focused ultrasound acts on the medium, so that the local refractive index of the medium is changed, light is regulated and controlled by a focused sound field when penetrating through the medium, and concentration of light energy in the medium is promoted; the handheld acousto-optic modulation device comprises a handheld base, a handheld top cover, an ultrasonic transducer, an acoustic holographic lens, a transparent panel, a transparent film and a sealing gasket; the ultrasonic transducer and the acoustical holographic lens are fixed in the handheld base through a connecting piece; the handheld base and the handheld top cover are connected with each other in a screwing mode. The transparent panel is adhered to the lower surface of the handheld base; and the transparent film is adhered to the upper surface of the boss of the handheld top cover. According to the invention, an optical path can be regulated and controlled in situ in a medium, and the device is noninvasive, is simple to operate, and can be conveniently applied to light therapy.

Description

Technical Field

[0001] The invention belongs to the field of acousto-optic modulation in scattered light regulation and control, and relates to a handheld acousto-optic modulation device and a light scattering suppression method. Background Art

[0002] Noninvasive propagation of visible or near-infrared light through living organisms has been used in a variety of fields, such as functional and structural medical imaging, photodynamic therapy, and photothermal therapy. However, due to the strong scattering of light within tissues, light energy is severely attenuated during transmission, hindering the ability to transmit light to areas deeper than a few millimeters. Therefore, the effectiveness of light-based methods for imaging, activating, and treating deep tissues is still limited.

[0003] To address the above issues, increasing the input power of light can compensate for the loss of light intensity caused by scattering, but may cause thermal damage. Implantable optical fibers and gradient refractive index lenses can be used to collect and guide light, effectively concentrating the photon energy. However, the invasiveness of these methods limits their application to specific sites in the body.

[0004] Acousto-optic modulation technology is a technology that uses sound waves to modulate the refractive index of light. In existing acousto-optic modulation technology, the light beam is usually modulated by using the principle of standing waves generated by a resonant cavity. However, in this technology, the transmission direction of ultrasound is perpendicular to the transmission direction of light, and the range of the acousto-optic effect is limited to its complex cavity, resulting in poor flexibility and cannot be applied to in vivo optical imaging and light therapy. Summary of the invention

[0005] The present invention solves the deficiencies of the prior art and provides a handheld acousto-optic modulation device and a method for reducing light scattering which have a simple structure, are easy to operate and have a fast response speed, and can be used to improve the concentration of light energy in a target area.

[0006] To achieve the above-mentioned purpose, the present invention first proposes a handheld acousto-optic modulation device and a method for suppressing light scattering, characterized in that the handheld acousto-optic modulation device, when in use, has a transparent film bonded to the upper surface tightly attached to a medium, uses focused ultrasound to act on the medium, thereby changing the local refractive index of the medium, and light passing through the medium will be regulated by the focused acoustic field, thereby promoting the concentration of light energy in the medium; the handheld acousto-optic modulation device comprises a handheld base, a handheld top cover, an ultrasonic transducer, an acoustic holographic lens, a transparent panel, a transparent film and a sealing gasket. The handheld acousto-optic modulation device comprises a handheld base, a handheld top cover, an ultrasonic transducer, an acoustic holographic lens, a transparent panel, a transparent film and a sealing gasket; the ultrasonic transducer and the acoustic holographic lens are fastened to the inside of the handheld base through a connector; the handheld base and the handheld top cover are connected to each other by screwing; the transparent panel is bonded to the lower surface of the handheld base; the transparent film is bonded to the upper surface of the boss of the handheld top cover.

[0007] Furthermore, the present invention provides a method for suppressing light scattering using a handheld acousto-optic modulation device, comprising the following steps:

[0008] The ultrasonic transducer is mounted at the bottom of the cavity of the handheld base, the acoustic holographic lens is placed on the upper surface of the ultrasonic transducer, and its position is fixed with fasteners to prevent it from moving.

[0009] The handheld top cover equipped with a sealing gasket is screwed together with the handheld base equipped with an ultrasonic transducer and an acoustic holographic lens until the handheld base hits the sealing gasket, thereby finally forming a sealed cavity.

[0010] A syringe is used to inject water into the sealed cavity through the water inlet conduit, while the adjacent exhaust conduit plays the role of exhausting air, and finally the entire cavity is filled with water.

[0011] The transparent film of the handheld acousto-optic modulation device is placed tightly against the surface of the medium, and an excitation module is used to excite the ultrasonic transducer to generate ultrasonic waves. The ultrasonic waves are modulated by the acoustic holographic lens to form a focused sound field in the form of longitudinal waves. The focused sound field acts on the medium, thereby changing the local refractive index of the medium. When light passes through the medium, it will be regulated by the focused sound field, thereby reducing the strong scattering of light in the medium.

[0012] Furthermore, the handheld acousto-optic modulation device can not only allow the transmission of spatial light, but also be integrated with optical fiber.

[0013] Furthermore, the ultrasonic transducer includes a piezoelectric layer, an electrode, a backing layer, a housing and a wire connector.

[0014] Furthermore, the piezoelectric layer of the ultrasonic transducer uses piezoelectric ceramics as piezoelectric material, uses a gold layer film as an electrode, uses epoxy resin as a backing layer of the ultrasonic transducer, and uses brass as a shell.

[0015] Furthermore, the ultrasonic transducer and the acoustic holographic lens have central openings, and the diameters of the circular holes of the ultrasonic transducer and the acoustic holographic lens are equal, and the handheld base, the handheld top cover, the ultrasonic transducer and the acoustic holographic lens are all coaxially installed.

[0016] Furthermore, the acoustic holographic lens is iteratively designed by an angular spectrum method and is used to modulate the phase of ultrasonic waves.

[0017] Furthermore, the handheld base, the handheld top cover and the acoustic holographic lens are all manufactured using a 3D printing process.

[0018] Furthermore, the top of the handheld top cover is a boss with a hole in the center and a transparent film bonded to the upper surface; the handheld base has a hole in the center and a transparent panel bonded to the lower surface.

[0019] Furthermore, after the ultrasonic transducer wire and the SMA connector pass through the hole of the base, the hole is sealed.

[0020] The beneficial effects of a handheld acousto-optic modulation device and a light scattering suppression method provided by the present invention are as follows: based on the principle of acousto-optic modulation, scattered light can be regulated in situ inside a medium, which is non-invasive; coaxial propagation of sound and light is achieved by generating a focused acoustic field in the form of longitudinal waves, making it possible to achieve acousto-optic modulation in living tissues; the handheld acoustic holographic device is easy to operate and has good robustness, providing a simple and effective strategy for living light therapy. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0022] Figure 1 A schematic diagram of the overall structure of a handheld acousto-optic modulation device provided in an embodiment of the present invention.

[0023] Figure 2 A schematic diagram of the structure of a piezoelectric ultrasonic transducer and an acoustic holographic lens provided in an embodiment of the present invention.

[0024] Figure 3 A schematic diagram of the principle of using a handheld acousto-optic modulation device to suppress light scattering provided in an embodiment of the present invention.

[0025] Figure 4 The present invention provides a method for verifying the effect of using a handheld acousto-optic modulation device in a photodynamic experiment. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] In the description of the embodiments of the present invention, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use, it is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0028] A handheld acousto-optic modulation device, such as Figure 1 As shown in a, the handheld acousto-optic modulation device consists of an ultrasonic transducer 1, an acoustic holographic lens 2, a handheld top cover 3, a handheld base 4, a transparent film 5, a transparent panel 6 and a sealing gasket 7.

[0029] like Figure 1 As shown in FIG. 2 , the ultrasonic transducer 1 and the acoustic holographic lens 2 are fixed in the handheld base 4, the transparent panel 6 is bonded to the lower surface of the handheld base, the transparent film 5 is bonded to the upper surface of the boss of the handheld top cover, the handheld top cover 3 and the handheld base 4 are connected by screwing together and sealed with a sealing gasket 7, and the handheld base 4 has holes on the side which are respectively connected to the water inlet duct and the exhaust duct.

[0030] like Figure 2 As shown, the ultrasonic transducer is composed of a piezoelectric layer 8, an electrode 9, a backing layer 10, a housing 11 and an SMA connector 12. The piezoelectric layer 8 uses PZT-4 ceramic as a piezoelectric material, a gold layer film is used as an electrode 9, epoxy resin is used as a backing layer 10 of the ultrasonic transducer, brass is used as a housing 11, and the SMA connector 12 is connected via a wire. The SMA connector 12 can be combined with an external active control program to achieve electrical connection of the transducer.

[0031] like Figure 2 As shown, the acoustic holographic lens is designed using an iterative angular spectrum method, and the ultrasonic beam is regulated based on the different thickness distributions of each pixel point on the surface of the acoustic lens. The amplitude and phase of the sound field can be accurately regulated to form a focused sound field.

[0032] Preferably, in this embodiment, the ultrasonic transducer and the acoustic holographic lens have central openings to allow light to pass through, and the circular holes of the ultrasonic transducer and the acoustic holographic lens have equal diameters, and the handheld base, handheld top cover, ultrasonic transducer and acoustic holographic lens are all coaxially mounted, and their center holes are all concentric.

[0033] Preferably, in this embodiment, the top of the handheld top cover is a boss with a central opening, and a transparent film is bonded to the upper surface; the handheld base has a central opening, and a transparent panel is bonded to the lower surface.

[0034] Preferably, in this embodiment, a hole is opened at the bottom of the handheld base to allow the ultrasonic transducer wire and the SMA connector to pass through.

[0035] Preferably, in this embodiment, after the ultrasonic transducer wire and the SMA connector pass through the hole opened in the base, the hole is sealed.

[0036] Preferably, in this embodiment, the handheld base, the handheld top cover and the acoustic holographic lens model are all made by 3D printing technology.

[0037] See also Figure 3 The embodiment of the present invention discloses a method for suppressing light scattering using a handheld acousto-optic modulation device, comprising the following steps:

[0038] S1: Install the ultrasonic transducer at the bottom of the handheld base cavity, place the acoustic holographic lens on the upper surface of the ultrasonic transducer, and fix its position with fasteners to prevent it from moving.

[0039] S2: Screw the handheld top cover equipped with a sealing gasket and the handheld base equipped with an ultrasonic transducer and an acoustic holographic lens together until the handheld base hits the sealing gasket, thereby finally forming a sealed cavity.

[0040] S3: Use a syringe to inject water into the sealed cavity through the water inlet conduit, while the adjacent exhaust conduit plays the role of exhausting, and finally fills the entire cavity with water.

[0041] S4: Place the transparent film of the handheld acousto-optic modulation device close to the surface of the medium, and use the excitation module to excite the ultrasonic transducer to generate ultrasonic waves. The ultrasonic waves are modulated by the acoustic holographic lens to form a focused sound field in the form of longitudinal waves. The focused sound field acts on the medium, thereby changing the local refractive index of the medium. When light passes through the medium, it will be regulated by the focused sound field, thereby promoting the concentration of light energy in the medium.

[0042] Preferably, in this embodiment, a handheld acousto-optic modulation device is used in a photodynamic experiment, and the yield of singlet oxygen is monitored to prove that the inhibitory effect of the handheld acousto-optic modulation device on light scattering can be used to enhance the efficiency of phototherapy.

[0043] Preferably, the photodynamic experiment of this embodiment adheres a medium with scattering properties to a transparent film of a handheld acousto-optic modulation device, and places a photosensitizer solution on the medium. When light passes through the medium and combines with the photosensitizer, singlet oxygen is generated. 1,3-diphenylisobenzofuran (DPBF) is used as a fluorescent probe. DPBF reacts with singlet oxygen, and the reaction is irreversible. This embodiment characterizes the yield of singlet oxygen by monitoring the absorbance change of DPBF.

[0044] The rate of decrease of DPBF absorbance in photodynamic experiment is as follows Figure 4 As shown, due to the suppression of light scattering by the portable acousto-optic modulation device, the photon energy is concentrated in the target area, so that the photosensitizer produces more singlet oxygen, and DPBF reacts with more singlet oxygen. This embodiment shows that the handheld acousto-optic modulation device can be used in light therapy and improve the efficiency of light therapy by reducing light scattering.

[0045] The above-described embodiments merely express the implementation methods of the present invention, but they cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection of the present invention.

Claims

1. A handheld acousto-optic modulation device and a method for suppressing light scattering, characterized in that: When the handheld acousto-optic modulation device is in use, the transparent film bonded to the upper surface is tightly attached to the medium, and focused ultrasound is used to act on the medium, thereby changing the local refractive index of the medium. When light passes through the medium, it will be regulated by the focused acoustic field, thereby promoting the concentration of light energy in the medium; the handheld acousto-optic modulation device includes a handheld base, a handheld top cover, an ultrasonic transducer, an acoustic holographic lens, a transparent panel, a transparent film and a sealing gasket. The handheld acousto-optic modulation device includes a handheld base, a handheld top cover, an ultrasonic transducer, an acoustic holographic lens, a transparent panel, a transparent film and a sealing gasket; the ultrasonic transducer and the acoustic holographic lens are fastened to the inside of the handheld base through a connector; the handheld base and the handheld top cover are connected to each other by screwing; the transparent panel is bonded to the lower surface of the handheld base; the transparent film is bonded to the upper surface of the boss of the handheld top cover.

2. A method for suppressing light scattering using a handheld acousto-optic modulation device according to claim 1, characterized in that: The following steps are involved: (1) An ultrasonic transducer is mounted at the bottom of a cavity of a handheld base, an acoustic holographic lens is placed on the upper surface of the ultrasonic transducer, and its position is fixed with fasteners to prevent it from moving. (2) The handheld top cover equipped with a sealing gasket is screwed together with the handheld base equipped with an ultrasonic transducer and an acoustic holographic lens until the handheld base is pressed against the sealing gasket, thereby finally forming a sealed cavity. (3) Use a syringe to inject water into the sealed cavity through the water inlet conduit. (4) The transparent film of the handheld acousto-optic modulation device is placed tightly against the surface of the medium, and an excitation module is used to excite the ultrasonic transducer to generate ultrasonic waves. The ultrasonic waves are modulated by the acoustic holographic lens to form a focused acoustic field in the form of longitudinal waves. The focused acoustic field acts on the medium, thereby changing the local refractive index of the medium. When light passes through the medium, it will be regulated by the focused acoustic field, thereby reducing the strong scattering of light in the medium.

3. A handheld acousto-optic modulation device as claimed in claim 1, characterized in that: The handheld AOM device not only allows the transmission of spatial light, but can also be integrated with optical fibers.

4. A handheld acousto-optic modulation device as claimed in claim 1, characterized in that: The ultrasonic transducer comprises a piezoelectric layer, an electrode, a backing layer, a housing and a wire connector.

5. A handheld acousto-optic modulation device as claimed in claims 1 and 3, characterized in that: The piezoelectric layer of the ultrasonic transducer uses piezoelectric ceramics as piezoelectric material, uses a gold layer film as an electrode, uses epoxy resin as a backing layer of the ultrasonic transducer, and uses brass as a shell.

6. A handheld acousto-optic modulation device as claimed in claims 1 and 3, characterized in that: The ultrasonic transducer and the acoustic holographic lens have central openings, and the diameters of the circular holes of the ultrasonic transducer and the acoustic holographic lens are equal. The handheld base, the handheld top cover, the ultrasonic transducer and the acoustic holographic lens are all coaxially installed.

7. A handheld acousto-optic modulation device as claimed in claim 1, characterized in that: The acoustic holographic lens is iteratively designed by the angular spectrum method and is used to modulate the phase of ultrasonic waves.

8. A handheld acousto-optic modulation device as claimed in claim 1, characterized in that: The handheld base, the handheld top cover and the acoustic holographic lens are all made by 3D printing technology.

9. A handheld acousto-optic modulation device as claimed in claim 1, characterized in that: The top of the handheld top cover is a boss with a hole in the center and a transparent film bonded to the upper surface; the handheld base has a hole in the center and a transparent panel bonded to the lower surface.

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