Device and method for driving liquid circulation through laser and detecting acoustic signal

Abstract

The invention relates to the technical field of light-controlled flow and sound communication, and discloses a device and method for driving liquid circulation and detecting sound signals through lasers, the device comprises a horizontally arranged annular cavity, and the annular cavity extends in the tangential direction to form a linear cavity; a metal substrate is arranged on the outer wall of the annular cavity at the intersection of the annular cavity and the linear cavity; the metal substrate is used for receiving laser energy and generating power for driving liquid in the annular cavity and the linear cavity to flow; and an acoustic converter connecting port is formed in the end part, far away from the annular cavity, of the linear cavity. By arranging the annular cavity, the flowing path of the liquid is converted, long-range and stable rotary circulation of the liquid driven by the laser is achieved, meanwhile, the communicated linear cavity is formed in the annular cavity and used for installing the acoustic converter connector, and acoustic signals can be monitored and measured at the same time under the condition that rotation of the liquid is not affected.

Description

Technical Field

[0001] The present invention relates to the field of optically controlled flow technology, and in particular to a device and method for laser-driven liquid circulation and detection of acoustic signals. Background Art

[0002] Optical flow control technology has a large number of applications in microfluidic systems, basic research in biology and chemistry, and medical devices. The use of light to drive fluids has excellent characteristics such as no energy loss, no contact and no pollution, and easy and precise control in time and space. Since photons have linear momentum and mechanical kinetic energy, lasers are widely used in this field due to their significant advantages of high intensity, high directionality and monochromaticity. Transferring the momentum of lasers to fluids and controlling fluids efficiently and accurately has been a research hotspot in recent decades. There are currently four main methods used to achieve optical flow control:

[0003] Light momentum drive. The light momentum is used to generate deformation and control the fluid. The laser beam is irradiated on the interface of two immiscible liquids with different refractive indices, and the light radiation pressure is generated to cause the liquid surface between the two liquid surfaces to be distorted, that is, the interface is distorted toward the side with the lower refractive index of the two liquids. Optical tweezers technology is also one of them. However, this technology can only be applied to the microscopic world.

[0004] Photothermal drive. The photothermal effect is used to locally change the surface tension of the liquid surface and thus control the fluid. When the laser is irradiated at the interface between two liquids, the temperature of the irradiated part rises. The temperature increase will cause the density of liquid molecules to decrease, resulting in a significant difference in the surface tension of the two liquid surfaces, and then form a surface tension gradient, causing the liquid to flow from the area with high surface tension to the area with low surface tension, forming the Marangoni effect. However, this technology has high requirements for the liquid.

[0005] Light modulated voltage drives fluid. Control is achieved by integrating photoconductive materials under the electrowetting electrode, that is, a charged tiny droplet is attached to an electrode covered with an optically conductive medium. By changing the laser irradiation, the conductivity of the medium itself will change, which will lead to a change in the potential difference, so that the attachment angle of the tiny droplet will become smaller, which can drive the droplet to move. However, this technology generates less power.

[0006] Photo-induced ultrasound drives fluid movement. In 2017, Wang et al. irradiated a 527nm pulsed laser into a cuvette filled with a gold nano-solution, focused the laser on the front surface of the cuvette, and after a few minutes or ten minutes of processing time, a CCD camera could be used to observe a strong straight jet ejection on the surface of the cuvette where the laser was incident. The maximum jet could reach 4cm / s. Injecting gold nanoparticles into the four walls of the cuvette or attaching a glass substrate coated with a nano-gold layer to the four walls of the cuvette can also produce a strong straight jet at the laser incident point. This is because gold has an absorption peak near 527nm. When a laser with a wavelength near the absorption peak on the metal spectrum is irradiated on the metal, the metal undergoes a surface plasmon resonance effect, which absorbs a large amount of laser light and then partially converts it into ultrasonic waves, which then pushes the fluid to make a directional motion perpendicular to the surface of the cuvette. The ultrasonic signal detector placed in the solution also successfully detected the ultrasonic signal. However, this technology only drives the jet to move in a straight line.

[0007] In view of this, this application is hereby filed. Summary of the invention

[0008] The problem with the prior art is that currently laser-driven fluid can only produce linear motion. The present invention provides a device and method for laser-driven liquid circulation and detection of acoustic signals, which can convert laser-driven linear motion into circular motion. At the same time, by adjusting the laser incident position, the laser can also drive the fluid to rotate in different directions, and detect the acoustic signal in the fluid under different fluid rotation states.

[0009] The present invention is achieved through the following technical solutions:

[0010] In a first aspect, the present invention provides a device for laser-driven liquid circulation and detecting acoustic signals, comprising a horizontally arranged annular cavity, wherein the annular cavity has a linear cavity extending along a tangential direction;

[0011] A metal substrate is provided on the outer wall of the annular cavity where the annular cavity intersects the linear cavity;

[0012] The metal substrate is used to receive laser energy and generate power to drive the liquid in the annular cavity and the linear cavity to flow;

[0013] An acoustic converter connection port is arranged at the end of the linear cavity away from the annular cavity.

[0014] The present invention changes the flow path of the liquid by setting an annular cavity, realizes laser-driven long-range and stable rotational circulation of the liquid, and simultaneously sets a connected straight cavity on the annular cavity for installing the acoustic converter connection port, which can monitor and measure the acoustic signal simultaneously without affecting the rotation of the liquid.

[0015] In a specific embodiment, the device is provided with a laser incident window extending to the metal substrate.

[0016] In a specific embodiment, both sides of the annular cavity are extended with linear cavities along the tangential direction, and the two linear cavities are located on the same side of the annular cavity;

[0017] Metal substrates are arranged on the outer walls of the intersections of the annular cavity and the two linear cavities.

[0018] The present invention sets two metal substrates, so when the two metal substrates are irradiated from two directions respectively, the liquid can produce different rotation directions. Metal substrates are designed on both sides of the device of the present invention. When the laser is on the metal substrate on the right side, the rotation direction of the fluid in the annular cavity is clockwise; when the laser is on the metal substrate on the left side, the rotation direction of the fluid in the annular cavity is counterclockwise; thereby realizing that one device controls the rotation of the fluid in two directions.

[0019] The control source of the device of the present invention is only laser, the control source is single, the control accuracy is high, no other physical field needs to be added, and the requirements for setting up the experimental environment are low. The small number of control sources also means that the results are not affected by other redundant conditions, and are only strictly related to the laser power, and have strong controllability.

[0020] The device of the present invention drives the liquid to rotate in a non-contact manner and does not require any external rotating shaft, wires, etc. The laser source can also be remotely controlled without direct contact with the device, and has higher flexibility.

[0021] Among them, the two acoustic converter connection ports are relatively close to the two metal substrates, and usually only one side of the metal substrate is used as the driving source. At this time, the acoustic converters installed at the two acoustic converter connection ports will become the proximal end and the distal end respectively, which are used to measure the sound signal conditions at different positions.

[0022] In a specific embodiment, the metal substrate is a quartz substrate implanted with gold ions.

[0023] In a specific embodiment, the metal substrate is a glass substrate plated with a gold layer.

[0024] In a specific embodiment, the thickness of the gold layer is 200-500 nm.

[0025] Gold nanoparticles in the metal substrate are used to convert the energy of the laser to move the fluid.

[0026] In a specific embodiment, the device further includes a laser and a convex lens arranged between the laser and the laser incident window.

[0027] In a specific embodiment, the cross-section of the annular cavity and the linear cavity is a rectangular structure, a circular structure, a trapezoidal structure or a triangular structure, etc. The function of the annular cavity and the linear cavity of the present invention is to provide a flow channel for the liquid, so the shape of the cross-section is not limited to the above shapes, as long as it does not produce a large resistance to the flow of the liquid.

[0028] In a specific embodiment, an acoustic transducer is installed at the acoustic transducer connection port.

[0029] In a second aspect, the present invention provides a method for laser-driven liquid circulation and detecting acoustic signals, comprising the following steps:

[0030] (1) Liquid is contained in the annular cavity and the linear cavity, and the liquid may be deionized water or a gold nanoparticle solution, so as to reduce the influence of irrelevant factors on the analysis;

[0031] (2) The light emitted by the laser is focused by a convex lens and irradiated onto a metal substrate with a laser incident window on one side;

[0032] (3) The metal substrate converts laser energy to drive the liquid to flow in a straight line perpendicular to the wall;

[0033] (4) When the liquid flows in the annular cavity, due to the existence of the curvature, the liquid is subject to greater resistance, so a small part of the liquid enters the bend of the annular cavity and the straight cavity used for acoustic signal transmission. However, at this time, the small part of the liquid is difficult to cause a large flow, and most of the liquid flows back to the metal substrate. The returned liquid is pushed again by the energy of the laser at the metal substrate to form a vortex, which drives the liquid in the annular cavity to flow and form an overall circulation.

[0034] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0035] 1. A device and method for laser-driven liquid circulation and acoustic signal detection provided by an embodiment of the present invention, by setting an annular cavity, the flow path of the liquid is changed, and the laser-driven liquid long-range and stable rotation circulation is realized. At the same time, a connected linear cavity is set on the annular cavity for installing an acoustic converter connection port, which can monitor and measure acoustic signals without affecting the rotation of the liquid;

[0036] 2. A device and method for laser-driven liquid circulation and acoustic signal detection provided by an embodiment of the present invention is provided with two metal substrates. When the two metal substrates are irradiated from two directions respectively, the liquid can produce different rotation directions. When the laser is directed to the metal substrate on the right side, the rotation direction of the fluid in the annular cavity is clockwise; when the laser is directed to the metal substrate on the left side, the rotation direction of the fluid in the annular cavity is counterclockwise; thereby realizing that one device controls the rotation of the fluid in two directions;

[0037] 3. The embodiment of the present invention provides a device and method for laser-driven liquid circulation and detection of acoustic signals. The control source is only laser, the control source is single, the control accuracy is high, no other physical field needs to be added, and the requirements for setting up the experimental environment are low. The small number of control sources also means that the results are not affected by other redundant conditions, and are only strictly related to the laser power, and have strong controllability;

[0038] 4. A device and method for driving liquid circulation and detecting acoustic signals provided by an embodiment of the present invention drives the liquid to rotate in a non-contact manner, does not require any external rotating shaft, wires, etc., and the laser source can also be remotely controlled without direct contact with the device, which is more flexible.

[0039] 5. An embodiment of the present invention provides a device and method for laser-driven liquid circulation and detection of acoustic signals. The device has a simple structure, and the annular cavity is composed of a regular structure, which is easy to process and realize. Traditional processes can meet the processing and production conditions, and the application cost is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0041] Figure 1 A top view of the structure of a device for driving liquid circulation and detecting acoustic signals provided by an embodiment of the present invention;

[0042] Figure 2 A front view of the structure of a device for driving liquid circulation and detecting acoustic signals provided by an embodiment of the present invention;

[0043] Figure 3 A side view of the structure of a device for driving liquid circulation and detecting acoustic signals provided by an embodiment of the present invention;

[0044] Figure 4 A schematic diagram of liquid flow in laser-driven liquid circulation provided in an embodiment of the present invention.

[0045] Marks and corresponding parts names in the attached drawings:

[0046] 1- annular cavity, 2- linear cavity, 3- metal substrate, 4- acoustic converter connection port, 5- laser incident window. DETAILED DESCRIPTION

[0047] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0048] In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present invention. However, it is apparent to one of ordinary skill in the art that these specific details need not be employed to practice the present invention. In other embodiments, in order to avoid obscuring the present invention, well-known materials or methods are not specifically described.

[0049] Throughout the specification, references to "one embodiment," "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in conjunction with the embodiment or example is included in at least one embodiment of the present invention. Therefore, the phrases "one embodiment," "an embodiment," "an example," or "an example" appearing in various places throughout the specification do not necessarily all refer to the same embodiment or example. In addition, particular features, structures, or characteristics may be combined in one or more embodiments or examples in any suitable combination and / or subcombination. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0050] Example 1

[0051] like Figure 1-Figure 3 As shown, an embodiment of the present invention provides a device for laser-driven liquid circulation and detecting acoustic signals, comprising a horizontally arranged annular cavity 1, wherein the annular cavity 1 has a linear cavity 2 extending along a tangential direction;

[0052] A metal substrate 3 is provided on the outer wall of the annular cavity 1 where the annular cavity 1 intersects the linear cavity 2;

[0053] The metal substrate 3 is used to receive laser energy and generate power to drive the liquid in the annular cavity 1 and the linear cavity 2 to flow;

[0054] An acoustic converter connection port 4 is provided at the end of the linear cavity 2 away from the annular cavity 1 .

[0055] The present invention changes the flow path of the liquid by setting an annular cavity, realizes laser-driven long-range and stable rotational circulation of the liquid, and simultaneously sets a connected straight cavity on the annular cavity for installing the acoustic converter connection port, which can monitor and measure the acoustic signal simultaneously without affecting the rotation of the liquid.

[0056] In a specific embodiment, the device is provided with a laser incident window 5 extending to the metal substrate 3 .

[0057] In a specific embodiment, both sides of the annular cavity 1 are extended with a linear cavity 2 along the tangential direction, and the two linear cavities 2 are located on the same side of the annular cavity 1;

[0058] Metal substrates 3 are provided on the outer walls of the intersections of the annular cavity 1 and the two linear cavities 2 .

[0059] The present invention sets two metal substrates, so when the two metal substrates are irradiated from two directions respectively, the liquid can produce different rotation directions. Metal substrates are designed on both sides of the device of the present invention. When the laser is on the metal substrate on the right side, the rotation direction of the fluid in the annular cavity is clockwise; when the laser is on the metal substrate on the left side, the rotation direction of the fluid in the annular cavity is counterclockwise; thereby realizing that one device controls the rotation of the fluid in two directions.

[0060] The control source of the device of the present invention is only laser, the control source is single, the control accuracy is high, no other physical field needs to be added, and the requirements for setting up the experimental environment are low. The small number of control sources also means that the results are not affected by other redundant conditions, and are only strictly related to the laser power, and have strong controllability.

[0061] The device of the present invention drives the liquid to rotate in a non-contact manner and does not require any external rotating shaft, wires, etc. The laser source can also be remotely controlled without direct contact with the device, and has higher flexibility.

[0062] Among them, the two acoustic converter connection ports are relatively close to the two metal substrates, and usually only one side of the metal substrate is used as the driving source. At this time, the acoustic converters installed at the two acoustic converter connection ports will become the proximal end and the distal end respectively, which are used to measure the sound signal conditions at different positions.

[0063] In a specific embodiment, the metal substrate 3 is a quartz substrate implanted with gold ions.

[0064] In a specific implementation, the metal substrate 3 is a glass substrate plated with a gold layer.

[0065] In a specific embodiment, the thickness of the gold layer is 200-500 nm.

[0066] Gold nanoparticles in the metal substrate are used to convert the energy of the laser to move the fluid.

[0067] In a specific embodiment, the device further includes a laser and a convex lens arranged between the laser and the laser incident window 5 .

[0068] In a specific embodiment, the cross-section of the annular cavity and the linear cavity is a rectangular structure, a circular structure, a trapezoidal structure or a triangular structure, etc. The function of the annular cavity and the linear cavity of the present invention is to provide a flow channel for the liquid, so the shape of the cross-section is not limited to the above shapes, as long as it does not produce a large resistance to the flow of the liquid.

[0069] In a specific embodiment, an acoustic converter is installed at the acoustic converter connection port 4 .

[0070] Example 2

[0071] like Figure 4 As shown, an embodiment of the present invention provides a method for laser-driven liquid circulation and detecting acoustic signals, comprising the following steps:

[0072] (1) Liquid is contained in the annular cavity and the linear cavity, and the liquid may be deionized water or a gold nanoparticle solution, so as to reduce the analysis of the influence of irrelevant factors, and an acoustic converter is installed at the acoustic converter connection port;

[0073] (2) The light emitted by the laser is focused by a convex lens and irradiated onto the metal substrate at the right laser incident window;

[0074] (3) The metal substrate converts laser energy to drive the liquid to flow in a straight line perpendicular to the wall;

[0075] (4) When the liquid flows in the annular cavity, due to the existence of the curvature, the liquid is subject to greater resistance, so a small part of the liquid enters the bend of the annular cavity and the straight cavity used for acoustic signal transmission. However, at this time, the small part of the liquid is difficult to cause a large flow, and most of the liquid flows back to the metal substrate. The returned liquid is pushed again by the energy of the laser at the metal substrate to form a vortex. The vortex drives the liquid in the annular cavity to flow clockwise to form an overall circulation.

[0076] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A device for laser-driven liquid circulation and detection of acoustic signals, characterized in that: It comprises a horizontally arranged annular cavity (1), wherein the annular cavity (1) has a linear cavity (2) extending along a tangential direction; A metal base plate (3) is provided on the outer wall of the annular cavity (1) at the intersection of the annular cavity (1) and the linear cavity (2); The metal substrate (3) is used to receive laser energy and generate power to drive the liquid in the annular cavity (1) and the linear cavity (2) to flow; An acoustic converter connection port (4) is provided at the end of the linear cavity (2) away from the annular cavity (1).

2. The device for laser-driven liquid circulation and detection of acoustic signals according to claim 1, characterized in that: Both sides of the annular cavity (1) are extended with straight cavities (2) along the tangential direction, and the two straight cavities (2) are located on the same side of the annular cavity (1); A metal base plate (3) is provided on the outer wall of the intersection of the annular cavity (1) and the two linear cavities (2).

3. The device for laser-driven liquid circulation and detection of acoustic signals according to claim 1, characterized in that: The metal substrate (3) is a quartz substrate injected with gold ions.

4. The device for laser-driven liquid circulation and detection of acoustic signals according to claim 1, characterized in that: The metal substrate (3) is a glass substrate plated with a gold layer.

5. The device for laser-driven liquid circulation and detection of acoustic signals according to claim 4, characterized in that: The thickness of the gold layer is 200-500 nm.

6. The device for laser-driven liquid circulation and detection of acoustic signals according to claim 1, characterized in that: The device is provided with a laser incident window (5) extending to the metal substrate (3).

7. The device for laser-driven liquid circulation and detection of acoustic signals according to claim 6, characterized in that: It also comprises a laser and a convex lens arranged between the laser and the laser incident window (5).

8. The device for laser-driven liquid circulation and detection of acoustic signals according to claim 1, characterized in that: The cross-sections of the annular cavity (1) and the linear cavity (2) are rectangular, circular, trapezoidal or triangular.

9. The device for laser-driven liquid circulation and detection of acoustic signals according to claim 1, characterized in that: An acoustic converter is installed at the acoustic converter connection port (4).

10. A method for laser-driven liquid circulation and detecting acoustic signals based on the device according to any one of claims 1 to 9, characterized in that: The steps include: (1) Liquid is contained in the annular cavity and the linear cavity; (2) irradiating the light emitted by the laser onto a metal substrate with a laser incident window on one side; (3) The metal substrate converts laser energy to drive the liquid to flow in a straight line; (4) When the liquid flows into the annular cavity, it encounters resistance. A small part of the liquid enters the bend of the annular cavity, and most of the liquid flows back to the metal substrate. The returned liquid is pushed by the energy of the laser again at the metal substrate to form a vortex. The vortex drives the liquid in the annular cavity to flow and form an overall circulation.

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