CN118449481A - A device and method for generating diversified particle patterns based on multi-order Lamb waves - Google Patents

Abstract

The present invention discloses a device and method for generating diversified particle patterns based on multi-order Lamb waves, including a radio frequency signal source for generating radio frequency signals; a Lamb wave device connected to the output end of the radio frequency signal source, receiving the radio frequency signal and generating a sound wave of a corresponding mode; a glass piece for carrying a particle solution; a coupling medium for coupling the Lamb wave device and the glass piece; when in use, the particle solution is placed on the glass piece. Compared with the traditional acoustofluidic method, the present invention has the advantage of diversified particle patterns; in addition, since the particles are manipulated on a glass sheet, secondary contamination of the particle solution to the acoustic wave device is avoided, and the repeatable use of the acoustic wave device is achieved, which has broad application prospects in the fields of acoustofluidic manipulation of cells, microparticles, etc.

Description

A device and method for generating diversified particle patterns based on multi-order Lamb waves

Technical Field

The present invention relates to a device and method for generating diversified particle patterns based on multi-order Lamb waves, and belongs to the field of acoustic wave technology application.

Background technique

Surface acoustic wave is an elastic wave that propagates along the surface of a solid. It was first discovered by British scientist Rayleigh in the process of studying seismic waves, so this wave is also called Rayleigh wave. In 1965, American scientists White and Wattmer excited acoustic waves by applying radio frequency signals to the interdigital electrodes on the piezoelectric substrate, laying the foundation for the application of surface acoustic wave devices. With the advancement of science, various forms of acoustic waves have been discovered, including: Xishawa waves, horizontal shear waves, Lamb waves and Love waves. Depending on the type of acoustic wave, they are used in different occasions. For example, Love waves and horizontal shear waves are generally used for liquid phase sensing because of their low attenuation in liquids. Rayleigh waves and Lamb waves will dissipate the energy of the acoustic wave into the liquid to generate acoustic flow force, and then generate flow inside the droplet, which can be used as microfluidic actuators.

In addition to being used as sensors and microfluidic actuators, surface acoustic waves can also manipulate particles/cells in fluids to produce various forms of particle/cell patterns. Under the action of the acoustic field, particles in the liquid are mainly subject to four forces: gravity, buoyancy, viscous resistance, and acoustic radiation force. In the vertical direction, since the density of the particles is similar to that of water, the gravity and buoyancy are equivalent, which can keep the particles in a suspended state; in the horizontal direction, the particles are subject to viscous resistance and acoustic radiation force. Since the particles are at the micron scale, the acoustic radiation force is much greater than the viscous resistance. Therefore, under the action of the acoustic radiation force, the particles will move to the node or antinode position, so that the microparticles and cells are arranged in an array under the action of the acoustic field, and the position accuracy can reach the micron level. The array arrangement of particles under the action of the acoustic field is also called acoustic tweezers technology. Traditional acoustofluidic devices are mainly manufactured on bulk lithium niobate substrates, and generally can only produce a single mode, which limits the generation of diversified particle/cell patterns. In addition, since the particle/cell solution is directly placed on the surface of the acoustic wave device for operation, this may cause pollution problems for the secondary use of the acoustic wave device. Therefore, there is an urgent need for a low-cost, simple, safe and reliable device and method to achieve the application of diversified particle/cell patterns.

Summary of the invention

The present invention provides a device and method for generating diversified particle patterns based on multi-order Lamb waves.

Acoustic wave microfluidics has become an important means of on-chip fluid manipulation and particle manipulation in fluids due to its advantages such as simple acoustic wave generation and control methods, diverse forms of interaction with fluids, and easy integration. The present invention adopts a piezoelectric film acoustic wave device. By designing the wavelength of the device to be much larger than the thickness of the substrate, multi-order Lamb wave modes are stimulated on the piezoelectric film substrate. The multi-order Lamb waves are coupled to the glass by using ultrasonic gel, and finally the generation of diversified particle patterns on the glass is achieved. At the same time, by changing the mode of the acoustic wave and the arrangement of the glass sheet on the surface of the acoustic wave device, the generation of diversified and multi-shaped particle patterns is achieved. In addition, since the sample is manipulated on the glass sheet, the contamination of the sample to the acoustic wave device is avoided, and the acoustic wave device can be reused. The present invention solves the problem that the existing acoustic fluidic devices have a single form of particle manipulation and are prone to device contamination.

A device for generating diversified particle patterns based on multi-order Lamb waves, comprising:

A radio frequency signal source, generating a radio frequency signal;

A Lamb wave device connected to the output end of the radio frequency signal source receives the radio frequency signal and generates a sound wave of a corresponding mode;

A glass piece that holds the particle solution;

A coupling medium is used to couple the Lamb wave device with the glass member, and couples the sound wave generated by the Lamb wave device to the glass member to form a sound wave propagating along the glass member;

When in use, a particle solution for generating the particle pattern is placed on the glass member to form a particle pattern.

Preferably, the Lamb wave device is a piezoelectric film type acoustic wave device, comprising a supporting substrate, a piezoelectric film and interdigital electrodes.

As an implementation scheme, the Lamb wave device is a piezoelectric film acoustic wave device, and the piezoelectric film acoustic wave device includes: a supporting substrate, a piezoelectric film and interdigital electrodes arranged on the supporting substrate.

Preferably, in the piezoelectric film acoustic wave device, the wavelength of the device is greater than the thickness of the substrate. Multiple order acoustic wave modes can be excited on the piezoelectric film acoustic wave device.

As an implementation scheme, the wavelength of the piezoelectric film acoustic wave device is 800-1200 μm, the supporting substrate is an aluminum plate with a thickness of 100-300 μm; the piezoelectric film is zinc oxide or aluminum nitride with a thickness of 5-8 μm; the material of the interdigitated electrode is aluminum or gold with a thickness of 50-200 nm.

As a further preference, the piezoelectric film is zinc oxide or aluminum nitride, and has a thickness ranging from 4 to 8 μm. As a further preference, the piezoelectric film is zinc oxide, and has a thickness of 5 μm.

As a further preference, the material of the interdigital electrodes is aluminum or gold, with a thickness of 50 to 200 nm. As a further preference, the material of the interdigital electrodes is aluminum, with a thickness of 100 nm.

As an embodiment, the wavelength of the piezoelectric film type acoustic wave device is 3 to 6 times the sum of the thickness of the supporting substrate and the piezoelectric film.

Preferably, the ratio of the wavelength of the Lamb wave device to the substrate thickness is 3 to 6. Further preferably, the ratio of the wavelength of the Lamb wave device to the substrate thickness is 5.5, and the wavelength is 1100 μm.

Preferably, the Lamb wave device can excite acoustic wave modes of order 1 to 4. More preferably, the Lamb wave device excites acoustic wave modes of order 3, including 0th order (A ₀ and S ₀ ), first order (A ₁ and S ₁ ) and second order (A ₂ and S ₂ ). Different particle patterns can be obtained by using different modes.

Preferably, the frequency range of the Lamb wave device is 1 to 30 MHz, and further preferably, the frequency range of the Lamb wave device is 1 to 12 MHz.

Preferably, the interdigital electrodes are connected to the SMA interface via conductive silver glue or a radio frequency probe, and the radio frequency signal source is connected to the SMA interface using a radio frequency connecting line. Further preferably, the interdigital electrodes are connected to the SMA interface via conductive silver glue.

As an implementation scheme, the thickness of the glass piece is 100-400 μm; more preferably, the thickness of the glass piece is 100-300 μm; as a further preferred embodiment, the thickness of the glass piece is 200 μm.

As an implementation scheme, the glass piece is fixed relative to the Lamb wave device by a clamping mechanism; the glass piece is a single glass sheet, or the glass piece is a double glass assembly consisting of two parallel glass sheets; when in use: for a glass piece with a single glass sheet structure, the particle solution is placed on the upper surface of the glass sheet; for a double glass assembly, the particle solution is placed between the two glass sheets.

As a further preference, the glass is placed perpendicular to or parallel to the surface of the acoustic wave device to produce a variety of particle patterns.

As an implementation scheme, the glass member is arranged in parallel with the Lamb wave device and is parallel-coupled via a coupling medium; or the glass member is laterally coupled to the Lamb wave device via a coupling medium.

As an implementation scheme, during lateral coupling, the side of the glass member in contact with the coupling medium is parallel to the long strip direction of the interdigital electrodes of the Lamb wave device.

As an embodiment, the coupling medium is ultrasonic gel. Lamb waves are coupled from the acoustic wave device to the glass member through the ultrasonic gel.

As an option, a device and method for generating diversified particle patterns based on multi-order Lamb waves include: a radio frequency signal source, a radio frequency connecting line, a Lamb wave device, ultrasonic gel and glass.

The radio frequency signal source is connected to the Lamb wave device through a radio frequency connecting line, and the sound waves generated on the Lamb wave device are coupled to the glass through the ultrasonic gel, forming sound waves propagating along the glass substrate, and finally forming an arrayed particle pattern inside the particle solution on the glass piece.

A method for generating diversified particle patterns based on multi-order Lamb waves, using any of the above-mentioned devices, adjusting the vibration mode of the Lamb wave device and/or adjusting the arrangement of the glass parts on the Lamb wave device to adjust the size and/or shape of the particle pattern.

Furthermore, according to the desired particle pattern, the vibration mode of the Lamb wave device is determined, thereby determining the output frequency of the radio frequency signal.

In actual use, the output frequency of the radio frequency signal should be the same as the resonant frequency of the acoustic wave mode to be excited each time.

The present invention provides a device and method for generating diversified particle patterns based on multi-order Lamb waves, comprising: generating a radio frequency signal using a radio frequency signal source, then applying the radio frequency signal to the interdigital electrodes (Lamb wave device) of an acoustic wave device, generating acoustic waves through the inverse piezoelectric effect of a piezoelectric film, then coupling the acoustic waves to a glass piece using an ultrasonic gel, and finally forming a particle pattern on the glass piece, while achieving the generation of diversified particle patterns by adjusting the acoustic wave mode and the arrangement of the glass on the surface of the acoustic wave device.

Before using the present invention, it is necessary to first use a network analyzer to test the RF signal of the Lamb wave device, and simulate the modes at different frequencies to determine the corresponding acoustic wave modes at different resonant frequencies. Then, a RF signal source is used to generate the frequency of the corresponding acoustic wave mode to be excited, and the frequency is input into the Lamb wave device to generate the acoustic wave of the corresponding mode.

During work, an RF signal source is connected to a Lamb wave device using an RF connecting line, and the sound waves generated by the Lamb wave device are coupled to the glass using ultrasonic gel. The particle solution is then placed on the glass or between two pieces of glass to generate an arrayed particle pattern.

Preferably, the device and method for generating diversified particle patterns based on multi-order Lamb waves comprises the following steps:

S1: Use a network analyzer to test the RF characteristics of the acoustic wave device, and use finite element analysis software to simulate the resonant mode of the acoustic wave device to determine the acoustic wave mode of the acoustic wave device at different resonant peaks;

S2: Use a radio frequency line to connect the radio frequency signal source to the interdigital electrodes of the acoustic wave device. The output frequency of the radio frequency signal source must be the same as the resonance frequency of the acoustic wave mode to be excited each time;

S3: Use ultrasonic gel to couple the acoustic waves generated by the Lamb wave device to the glass, and place the particle solution on the surface of the glass or between two glass pieces. Use the acoustic pressure field generated inside the droplet by the acoustic waves propagating on the glass to complete the array generation of the particle pattern. The size of the particle pattern can be achieved by adjusting the excitation mode/frequency of the acoustic wave device.

Preferably, the power applied to the Lamb wave device by the RF signal source is 0.4-0.8W. Further preferably, the RF power applied to the Lamb wave device is 0.5W.

Preferably, the particle diameter in the particle solution is 1 to 20 μm, and more preferably, the particle diameter of the solution is 10 μm.

Preferably, the size of the single particle pattern unit is 50 to 800 μm, and further preferably, the size of the single particle pattern unit is 60 to 590 μm.

As a preferred solution, the present invention is a device for generating diversified particle patterns based on multi-order Lamb waves, which includes: a radio frequency signal source, a radio frequency connecting line, a Lamb wave device, one or two pieces of glass and a CCD camera, and also includes ultrasonic gel. The radio frequency signal source is connected to the Lamb wave device by the radio frequency connecting line, and the sound wave is coupled to the glass by the ultrasonic gel, and finally an arrayed particle pattern is generated inside the particle solution on the glass. The shape and size of the particle pattern can be adjusted by the sound wave mode and the arrangement of the glass on the surface of the sound wave device.

The present invention discloses a method for generating diversified particle patterns based on multi-order Lamb waves. The method adopts a piezoelectric thin film acoustic wave device. By designing the wavelength of the device to be greater than the thickness of the substrate, multi-order acoustic wave modes are excited on the piezoelectric thin film acoustic wave device, and the multi-order acoustic wave modes are coupled to the glass through ultrasonic gel. Finally, by adjusting the excitation mode of the acoustic wave and the arrangement of the glass sheet on the acoustic wave device, the generation of diversified particle patterns is achieved.

The present invention proposes a device and method for generating diversified particle patterns based on multi-order Lamb waves, which has the following advantages:

(1) The present invention couples acoustic waves to glass to generate particle patterns, thereby avoiding the contamination of acoustic wave devices by particle solution samples and achieving repeatable use of acoustic wave devices. It has broad application prospects in the fields of acoustic fluidic manipulation of cells and particles.

(2) The present invention realizes the excitation of multi-order acoustic wave modes based on piezoelectric thin film acoustic wave devices, and realizes the generation of diversified particle patterns based on multi-order acoustic wave modes, which has the advantages of simple operation and low cost.

(3) The present invention realizes various shapes of particle arrangement patterns by adjusting the arrangement of the glass sheets. Compared with the traditional acoustofluidic method, it has the advantage of diversified particle patterns and enriches the forms of acoustofluidic patterns.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a schematic diagram of an experimental device for generating diversified particle patterns based on multi-order Lamb waves proposed in the present invention, wherein: 1 is a radio frequency signal source, 2 is a radio frequency connecting line, 3 is a Lamb wave acoustic wave device, 4 is an ultrasonic gel, 5 is a particle solution, 6 is glass, and 7 is a CCD camera.

FIG2 is a schematic diagram of the structure of the Lamb wave device used in the present invention, wherein 3a is an interdigitated electrode, 3b is a piezoelectric film, and 3b is a supporting substrate.

FIG. 3 is a physical picture of the Lamb wave device used in the present invention.

FIG. 4 shows the radio frequency characteristics of the Lamb wave device used in the present invention and the vibration modes of each order of Lamb waves obtained by simulation.

Figure 5 is a schematic diagram of the present invention (a) placing a single glass sheet perpendicular to the acoustic wave device and placing a droplet on the glass sheet, (b) a sound pressure diagram formed inside the droplet on the glass sheet using _A0 mode excitation, (c) a sound pressure diagram formed inside the droplet on the glass sheet using _S0 mode excitation, (d) a particle pattern generated inside the particle solution on the glass sheet using _A0 mode driving, and (e) a particle pattern generated inside the particle solution on the glass sheet using _S0 mode driving.

Figure 6 is a schematic diagram of the present invention (a) placing two glass sheets perpendicular to the acoustic wave device and placing a liquid between the two glass sheets, (b) an acoustic pressure diagram formed inside the liquid between the two glass sheets by using _A0 mode excitation, (c) an acoustic pressure diagram formed inside the liquid between the two glass sheets by using _S0 mode excitation, (d) a particle pattern generated inside the particle solution between the two glass sheets by using _A0 mode driving, and (e) a particle pattern generated inside the particle solution between the two glass sheets by using _S0 mode driving.

Figure 7 is _a schematic diagram of the present invention (a) placing a single glass sheet parallel to the acoustic wave device and placing a droplet on the glass sheet, (b) the sound pressure diagram formed inside the proximal droplet using _A0 mode excitation, (c) the sound pressure diagram formed inside the distal droplet using A0 mode excitation, (d) the particle pattern generated inside the proximal particle solution using _A0 mode drive, and (e) the particle pattern generated inside the distal particle solution using _A0 mode drive.

FIG8 shows particle patterns generated by the present invention on glass placed parallel to the acoustic wave device using (a) _A0 mode, (b) _S0 mode, (c) _A1 mode, and (d) _A2 mode driving.

Detailed ways

In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below through specific implementation methods in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

The present invention proposes a device and method for generating diversified particle patterns based on multi-order Lamb waves, wherein the device mainly includes a radio frequency signal source, a radio frequency connecting line, a Lamb wave device, an ultrasonic gel and glass. In the experiment, a radio frequency signal is generated by a radio frequency signal source, and then the radio frequency signal is input to the interdigital electrodes of the Lamb wave device through the radio frequency connecting line. Under the excitation of the radio frequency signal, the interdigital electrodes generate acoustic waves on the piezoelectric film, which propagate along the supporting substrate of the Lamb wave device, and then the acoustic waves propagating on the substrate are coupled to the glass through the ultrasonic gel, and finally an arrayed particle pattern is generated inside the particle solution placed on the glass or between two pieces of glass. By adjusting the excitation frequency of the radio frequency signal source, the Lamb wave device can be resonated in different modes, and the size adjustment or conversion of the particle pattern unit can be achieved based on the acoustic waves of different resonant modes. At the same time, adjusting the arrangement of the glass sheet on the acoustic wave device can achieve the shape adjustment of the particle pattern.

The present invention proposes a device and method for generating diversified particle patterns based on multi-order Lamb waves, and its experimental establishment schematic diagram is shown in Figure 1, including: a radio frequency signal source 1, a radio frequency connecting line 2, a Lamb wave device 3, an ultrasonic gel 4, a particle solution 5, a glass 6, and a CCD camera 7.

The radio frequency signal source 1 is mainly used to generate radio frequency signals, and the output frequency of the radio frequency signals can be adjusted according to the acoustic wave mode to be excited.

The radio frequency connecting line 2 is mainly used to connect the radio frequency signal source 1 and the Lamb wave device 3, and input the radio frequency signal to the interdigital electrodes of the Lamb wave device.

The Lamb wave device 3 is mainly used to stimulate Lamb waves on the piezoelectric film through the inverse piezoelectric effect after receiving the RF signal output by the RF signal source 1. The acoustic vibration mode of the Lamb wave can be successively excited by adjusting the output frequency of the RF signal source 1.

The ultrasonic gel 4 is mainly used to couple the sound waves propagating on the Lamb wave device 3 to the glass 6 to form sound waves propagating along the glass substrate.

The particle solution 5 is placed on a glass 6 or between two glasses 6 , and a CCD camera 7 is used to observe the particle pattern generated by the particle solution on the glass 6 or between two glasses 6 under the action of the sound wave.

Before the experiment, the relevant instruments and components are first placed on the experimental table in the order of Figure 1. During the experiment, the RF signal source 1 generates an RF signal, which is input to the interdigital electrode 3a of the Lamb wave device 3 through the RF connecting line 2. Under the excitation of the RF signal, the interdigital electrode 3a generates sound waves on the piezoelectric film 3b through the inverse piezoelectric effect. The sound waves are coupled from the Lamb wave device 3 to the glass 6 through the ultrasonic gel 4, and finally form propagating sound waves on the glass 6. When the particle solution 5 is placed on the glass 6, under the acoustic radiation force generated by the sound field on the objects inside the droplet, the particles will accumulate to the pressure point to form a patterned particle array.

Example 1: Using multi-order Lamb waves to generate an arrayed particle pattern on a single piece of glass placed perpendicular to the acoustic wave device

In the embodiment of the present invention, the RF signal source used is a RF source (RIGOL, DSG 815) produced by RIGOL Technology Co., Ltd., with a frequency range of 9kHz to 1.5GHz and a power range of -110dbm to 13dbm; the Lamb wave device used is a piezoelectric thin film acoustic wave device with a device wavelength of 1100μm, the piezoelectric film is zinc oxide with a thickness of about 5μm, the supporting substrate is an aluminum plate with a thickness of 200μm, and the material of the interdigital electrode is aluminum with a thickness of 100nm; the glass used is a glass sheet produced by Corning Glass Products Co., Ltd. with a thickness of 200μm; the particle solution used is a polystyrene ball solution with a diameter of 10μm.

The specific experimental steps of this embodiment are as follows:

S1: Using a network analyzer to test the radio frequency characteristics of the Lamb wave device 3, FIG4 shows the radio frequency characteristics of the Lamb wave device used in the present invention and the simulated vibration modes of each order of Lamb waves. In this embodiment, the A ₀ mode and the S ₀ mode are used for experiments to further determine the resonant frequencies corresponding to the Lamb wave device 3 at the A ₀ mode and the S ₀ mode; the output frequency of the radio frequency signal source 1 is determined according to the resonant frequency;

S2: Connect the RF signal source 1 to the Lamb wave device 3 using the RF connecting line 2, then place the glass sheet 6 perpendicular to the Lamb wave device 3, and keep the contact edge coupled with the Lamb wave device 3 through the coupling gel 4 parallel to the long strip direction of the interdigital electrode of the Lamb wave device 3, and fix the two by a clamping device, the contact point between the glass sheet 6 and the Lamb wave device 3 is coated with ultrasonic gel 4 for coupling sound waves, and then drop the polystyrene ball solution 5 on the glass sheet 6;

S3: Adjust the output frequency of the RF signal source 1 to the corresponding frequency values of the A ₀ mode and the S ₀ mode of the Lamb wave device 3, adjust the RF power to 0.5 W, and observe the particle patterns formed by the particle solution 5 on the glass sheet 6 under the driving of the A ₀ mode and the S ₀ mode.

FIG2 is a schematic diagram of the structure of a Lamb wave device 3 used in some embodiments of the present invention, wherein 3a is an interdigitated electrode, 3b is a piezoelectric film, and 3c is a supporting substrate.

FIG3 is a physical picture of the Lamb wave device used in the present invention. The wavelength of the device is 1100 μm, the thickness of the piezoelectric zinc oxide film is about 5 μm, the thickness of the aluminum substrate is 200 μm, the thickness of the interdigital electrode is 100 nm, and the number of electrode pairs is 20.

FIG4 is a radio frequency characteristic curve of the Lamb wave device used in some embodiments of the present invention and the vibration modes under various modes. It can be seen that the Lamb wave device can excite _A0 mode, _S0 mode, _A1 mode, _S1 mode, _A2 mode and _S2 mode.

Figure 5 is a schematic diagram of the placement of the sound wave and the glass sheet and the placement of the droplet on the glass sheet in Example 1 of the present invention, the sound pressure field formed by the simulated sound wave inside the droplet, and the particle pattern formed, wherein (a) is a schematic diagram of the placement of the glass sheet perpendicular to the sound wave device and the placement of the droplet on the glass sheet, (b) is a sound pressure diagram formed inside the droplet on the glass sheet using _A0 mode excitation, (c) is a sound pressure diagram formed inside the droplet on the glass sheet using _S0 mode excitation, (d) is a particle pattern generated inside the particle solution on the glass sheet using _A0 mode driving, and (e) is a particle pattern generated inside the particle solution on the glass sheet using _S0 mode driving.

Example 2: Multi-order Lamb waves are used to generate an arrayed particle pattern between two pieces of glass placed perpendicular to the acoustic wave device.

In Example 2 of the present invention, the RF signal source 1, RF connecting line 2, acoustic wave device 3, ultrasonic gel 4, and particle solution 5 used are the same as those in Example 1, except that the single glass sheet 6 originally placed perpendicular to the acoustic wave device is replaced with two pieces, and the contact between the two glass sheets 6 and the acoustic wave device 3 is coated with ultrasonic gel 4 to facilitate acoustic wave coupling.

The specific experimental steps of Example 2 are as follows:

S1: Using a network analyzer to test the radio frequency characteristics of the Lamb wave device 3, determine the resonant frequencies of the Lamb wave device 3 corresponding to the A ₀ mode and the S ₀ mode; and determine the output frequency of the radio frequency signal source 1 according to the resonant frequencies;

S2: Use the RF connection line 2 to connect the RF signal source 1 to the Lamb wave device 3, then place two glass sheets 6 perpendicular to the Lamb wave device 3, and keep the coupling edge of the glass 6 and the acoustic wave device 3 parallel to the long strip direction of the interdigital electrode of the Lamb wave device 3, fix the two by a clamping device, and apply ultrasonic gel 4 at the contact point between the glass sheet 6 and the Lamb wave device 3 for coupling acoustic waves, and then inject a polystyrene ball solution 5 between the two glass sheets 6;

S3: Adjust the output frequency of the RF signal source 1 to the corresponding frequency values of the A ₀ mode and the S ₀ mode of the Lamb wave device 3, adjust the RF power to 0.5 W, and observe the particle patterns formed by the particle solution 5 between the two glass sheets 6 under the driving of the A ₀ mode and the S ₀ mode.

Figure 6 is a schematic diagram of the placement of the sound wave and the glass sheets and the liquid in Example 2 of the present invention, the sound pressure field formed by the simulated sound wave inside the droplet, and the particle pattern formed, wherein (a) is a schematic diagram of placing two glass sheets perpendicular to the sound wave device and placing the liquid between the glass sheets, (b) is a sound pressure diagram formed inside the liquid between the two glasses using _A0 mode excitation, (c) is a sound pressure diagram formed inside the liquid between the two glasses using _S0 mode excitation, (d) is a particle pattern generated inside the particle solution between the two glasses using _A0 mode driving, and (e) is a particle pattern generated inside the particle solution between the two glasses using S0 mode driving.

Example 3: Using multi-order Lamb waves to generate an arrayed particle pattern on a single piece of glass placed parallel to the acoustic wave device.

In Example 3 of the present invention, the RF signal source 1, RF connecting line 2, acoustic wave device 3, ultrasonic gel 4, and particle solution 5 used are the same as those in Examples 1 and 2, except that a single glass sheet 6 is placed parallel to the acoustic wave device 3, and ultrasonic gel 4 is coated between the glass sheet 6 and the acoustic wave device 3 to facilitate acoustic wave coupling.

The specific experimental steps of Example 3 are as follows:

S1: using a network analyzer to test the radio frequency characteristics of the Lamb wave device 3, and determining the resonant frequencies of the Lamb wave device 3 corresponding to the A ₀ , S ₀ , A ₁ , and S ₁ modes; and determining the output frequency of the radio frequency signal source 1 according to the resonant frequencies;

S2: Connect the RF signal source 1 to the Lamb wave device 3 using the RF connecting line 2, then place a single glass sheet 6 parallel to the acoustic wave device 3, the contact between the glass sheet 6 and the Lamb wave device 3 is coated with ultrasonic gel 4 for coupling acoustic waves, and then drop a polystyrene ball solution 5 onto the glass sheet 6;

S3: Adjust the output frequency of the RF signal source 1 to the corresponding frequency values of the A ₀ , S ₀ , A ₁ , S ₁ modes of the Lamb wave device 3 , adjust the RF power to 0.5 W, and observe the particle patterns formed by the particle solution 5 on the single glass sheet 6 under the driving of the corresponding acoustic wave modes.

Figure 7 is a schematic diagram of the placement of the acoustic wave and the glass sheet, the placement of the droplet on the glass sheet, the acoustic pressure field formed by the simulated acoustic wave inside the droplet, and the particle pattern formed in Example 3 of the present invention, wherein (a) is a schematic diagram of placing a single glass sheet parallel to the acoustic wave device and placing the droplet on the glass sheet, (b) is a sound pressure diagram formed inside the proximal droplet using _{A0 mode} excitation, (c) is a sound pressure diagram formed inside the distal droplet using _A0 mode excitation, (d) is a particle pattern generated inside the proximal particle solution using A0 mode drive, and (e) is a particle pattern generated inside the distal particle solution using _A0 mode drive.

FIG8 shows particle patterns generated by the present invention using the experimental apparatus shown in FIG7(a) using (a) _A0 mode, (b) _S0 mode, (c) _A1 mode, and (d) _A2 mode on glass placed parallel to the acoustic wave device.

The above contents are further detailed descriptions of the present invention in combination with specific implementation methods, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the scope of protection of the present invention.

Claims (10)

1. A device for generating diversified particle patterns based on multi-order Lamb waves, comprising: A radio frequency signal source, generating a radio frequency signal; A Lamb wave device connected to the output end of the radio frequency signal source receives the radio frequency signal and generates a sound wave of a corresponding mode; A glass piece that holds the particle solution; A coupling medium is used to couple the Lamb wave device with the glass member, and couples the sound wave generated by the Lamb wave device to the glass member to form a sound wave propagating along the glass member; When in use, a particle solution is placed on a glass piece to form a particle pattern. 2. The device for generating diversified particle patterns based on multi-order Lamb waves according to claim 1 is characterized in that the Lamb wave device is a piezoelectric film acoustic wave device, and the piezoelectric film acoustic wave device includes: a supporting substrate, a piezoelectric film and interdigital electrodes arranged on the supporting substrate. 3. The device for generating diversified particle patterns based on multi-order Lamb waves according to claim 2 is characterized in that the wavelength of the piezoelectric film type acoustic wave device is 800-1200 μm, the supporting substrate is an aluminum plate with a thickness of 100-300 μm; the piezoelectric film is zinc oxide or aluminum nitride with a thickness of 5-8 μm; the material of the interdigitated electrode is aluminum or gold with a thickness of 50-200 nm. 4. The device for generating diversified particle patterns based on multi-order Lamb waves according to claim 2 is characterized in that the wavelength of the piezoelectric film acoustic wave device is 3 to 6 times the sum of the thickness of the supporting substrate and the piezoelectric film, and the Lamb wave device can excite an acoustic wave mode order of 1 to 4. 5. The device for generating diversified particle patterns based on multi-order Lamb waves according to claim 1 is characterized in that the glass piece is relatively fixed to the Lamb wave device through a clamping device; the glass piece is a single glass sheet, or the glass piece is a double glass assembly composed of two parallel glass sheets; when in use: for a glass piece with a single glass sheet structure, the particle solution is placed on the upper surface of the glass sheet; for a double glass assembly, the particle solution is placed between the two glass sheets. 6. The device for generating diversified particle patterns based on multi-order Lamb waves according to claim 1 is characterized in that the glass piece is arranged in parallel with the Lamb wave device and is parallel coupled through a coupling medium; or the glass piece is placed perpendicular to the acoustic wave device and is laterally coupled with the Lamb wave device through a coupling medium. 7. The device for generating diversified particle patterns based on multi-order Lamb waves according to claim 6 is characterized in that, during lateral coupling, the edge of the glass member in contact with the coupling medium is parallel to the long strip direction of the interdigital electrodes of the Lamb wave device. 8. The device for generating diversified particle patterns based on multi-order Lamb waves according to claim 1, characterized in that the coupling medium is ultrasonic gel. 9. A method for generating diversified particle patterns based on multi-order Lamb waves, characterized in that the size and/or shape of the particle pattern is adjusted by using the device described in any one of claims 1 to 8 by adjusting the vibration mode of the Lamb wave device and/or adjusting the arrangement of the glass parts on the Lamb wave device. 10. The method for generating diversified particle patterns based on multi-order Lamb waves according to claim 9 is characterized in that the vibration mode of the Lamb wave device is determined according to the required particle pattern, and then the output frequency of the radio frequency signal is determined.