阅读说明：本技术 表面波时频调控的局域化异质形复合材料制备装置及方法 (Device and method for preparing localized heterogeneous composite material regulated and controlled by surface wave time frequency ) 是由 汪延成 韩晨阳 梅德庆 许诚瑶 于 2020-05-11 设计创作，主要内容包括：本发明公开了一种表面波时频调控的局域化异质形复合材料制备装置及方法。将功能微粒、光敏液体与光引发剂混合均匀,步向一对变频率声表面波换能器输入频率、持续时间、间断时间且有时间差的周期性时频调控正弦信号,一对变频率声表面波换能器被激励出对应的声表面驻波,耦合入液槽内部后在光敏液体内形成局域化声场,光敏液体内功能微粒受到局域化声场的声辐射力作用,形成稳定的阵列状分布；打开紫外光源固化完成制造。本发明在液槽内部实现局域化的声场分布,实现对应局域化异质形复合材料的制备,解决了声表面波辅助异质性复合材料制备区域选择性差的问题。(The invention discloses a device and a method for preparing a localized heterogeneous composite material regulated and controlled by surface wave time frequency. Uniformly mixing functional particles, photosensitive liquid and a photoinitiator, inputting periodic time-frequency regulation sinusoidal signals with frequency, duration and interruption time and time difference to a pair of variable-frequency surface acoustic wave transducers, exciting the pair of variable-frequency surface acoustic wave transducers to form corresponding surface acoustic standing waves, coupling the surface acoustic standing waves into a liquid tank, and forming a localized sound field in the photosensitive liquid, wherein the functional particles in the photosensitive liquid are subjected to the action of acoustic radiation force of the localized sound field to form stable array-shaped distribution; and turning on an ultraviolet light source to cure to finish the manufacture. The invention realizes the localized sound field distribution in the liquid tank, realizes the preparation of the corresponding localized heterogeneous composite material, and solves the problem of poor regional selectivity of the preparation of the surface acoustic wave assisted heterogeneous composite material.)

1. A device for preparing a localized heterogeneous composite material regulated and controlled by surface wave time frequency is characterized in that:

the pair of frequency-variable surface acoustic wave transducers (2) are distributed on the surfaces of two sides of the lithium niobate wafer (1), the liquid tank (3) is placed on the surface of the middle part of the lithium niobate wafer (1) between the pair of frequency-variable surface acoustic wave transducers (2), the liquid tank (3) is filled with a mixture (5) of photosensitive liquid, functional particles and a photoinitiator, and the ultraviolet light source (4) is placed under the lithium niobate wafer (1).

2. The device for preparing a localized heterogeneous composite material by surface wave time-frequency modulation according to claim 1, wherein: the pair of frequency-variable surface acoustic wave transducers (2) are interdigital transducers, the finger width of the interdigital transducers continuously changes along the finger length direction, and the finger length direction is a straight line or an arc, so that an interdigital transducer and an arc interdigital transducer are respectively formed.

3. The device for preparing a localized heterogeneous composite material by surface wave time-frequency modulation according to claim 2, wherein: after a pair of frequency-variable surface acoustic wave transducers (2) are excited by a sinusoidal signal, surface acoustic waves with different frequencies are generated on the surface of the lithium niobate wafer (1) and in parallel to the finger length direction, the middle area of the lithium niobate wafer (1) between the pair of frequency-variable surface acoustic wave transducers (2) is overlapped to form a surface acoustic standing wave, and the liquid tank (3) is positioned above the area formed by the surface acoustic standing wave.

4. The device for preparing a localized heterogeneous composite material by surface wave time-frequency modulation according to claim 1, wherein: ultraviolet light emitted by the ultraviolet light source (4) penetrates through the transparent lithium niobate wafer (1) to irradiate into the liquid tank (3) to carry out photocuring on the photosensitive liquid in the liquid tank (3).

5. The device for preparing a localized heterogeneous composite material by surface wave time-frequency modulation according to claim 1, wherein: the functional particles include, but are not limited to, metal powder, organic particles, and cells.

6. The preparation method of the surface wave time-frequency regulated localized heterogeneous composite material applied to the device of any one of claims 1 to 5 is characterized by comprising the following steps:

step 1: uniformly mixing functional particles, photosensitive liquid and a photoinitiator, and putting the mixture into a liquid tank (3) through a liquid transfer device;

step 2: inputting frequency f to a pair of variable frequency SAW transducers (2)₁Duration t₁Off time t₂The time difference is provided with a periodic time frequency regulation sinusoidal signal, so that a pair of frequency-variable surface acoustic wave transducers (2) are excited to form corresponding surface acoustic standing waves, the surface acoustic standing waves are coupled into the liquid tank (3) and then form a localized sound field in the photosensitive liquid, and functional particles in the photosensitive liquid are acted by the acoustic radiation force of the localized sound field to form stable array distribution;

and step 3: and (3) turning on the ultraviolet light source (4) to cure the photosensitive liquid to finish the manufacture of the localized heterogeneous composite material, wherein the functional particles are fixedly distributed in the localized sound field range (6) in an array shape.

7. The method of claim 6, wherein the surface wave time-frequency controlled localized heterogeneous composite material is prepared by: the functional particle material includes but is not limited to metal powder, organic particles and cells.

8. The method of claim 6, wherein the surface wave time-frequency controlled localized heterogeneous composite material is prepared by: the periodic time-frequency regulation sinusoidal signals respectively input by the pair of frequency-variable surface acoustic wave transducers (2) have the same period, and each period is formed by the duration of t₁With a sinusoidal signal of duration t₂Is connected to zero input signal for a duration t₁The frequency of the internal sinusoidal signal being f₁Furthermore, a time difference t exists between the periodic time-frequency regulation sinusoidal signals of a pair of frequency conversion surface acoustic wave transducers (2)_c。

Technical Field

The invention relates to a rapid preparation technology, in particular to a device and a method for preparing a localized heterogeneous intelligent composite material based on surface wave time-frequency regulation.

Background

The intelligent composite material member is a novel material system integrating sensing, controlling and executing functions, the functional particles in the member can sense the change of external factors such as heat, light, electricity, magnetism, stress and the like, the material generates expected response according to the change information, and finally the member is controlled to realize dynamic adjustment. The intelligent composite material member can be divided into two parts of a base material and a functional medium, wherein the base material determines the geometric appearance of the member and plays a role in bearing external load; the functional medium is usually a simple substance or a compound with specific physicochemical properties, such as dielectric, piezoelectric, photosensitive, catalytic and adsorbing materials and the like, and plays a role in sensing and executing in the intelligent composite material component. Besides the geometric shape and the self-property of the functional medium, the key factor influencing the perception and execution of the intelligent composite material component is the internal spatial distribution characteristic of the functional medium, and the internal spatial distribution characteristic can be specifically classified into a homogeneous type and a heterogeneous type. The distribution of the functional medium in the homogeneous intelligent composite material member is uniform, so that any part of the member has the same response under the same external factor change. The functional medium distribution in the heterogeneous intelligent composite material component has a specific orientation or arrangement rule, and the component has anisotropy in space at the moment, so that the function and application potential of the intelligent composite material component are greatly expanded.

For the manufacture of heterogeneous intelligent composite material members, the current common method is to combine magnetic field or electric field auxiliary arrangement with photocuring three-dimensional printing, however, the electric/magnetic field auxiliary arrangement requires that the functional medium itself has electromagnetic properties, and for other functional media such as ceramics, high molecular polymers and biological cells, the arrangement method is useless, so the application range is limited. The surface acoustic wave auxiliary particle arrangement is a non-contact control technology, can realize the arrangement and movement of substance particles in fluid, and has no specific requirements on the shape and physical properties of the substance. In recent years, the surface acoustic wave auxiliary particle arrangement technology has received wide attention and research from scholars at home and abroad in the fields of cell, macromolecular protein arrangement and biological micro-fluidic chip research. Therefore, there is also a method proposed by researchers to arrange functional particles in a photosensitive liquid using a sound field, and then to perform a process of producing a heterogeneous intelligent composite material by photocuring. However, due to the limitation of the distribution of the surface waves on the lithium niobate wafer, the functional particles are often arranged in a single array in the manufacturing result, and the selectivity of the arrangement range and the position of the functional particles needs to be realized by a waveguide structure or by changing an acoustic boundary, so that the operation is complex and the dynamic regulation capability is poor. In summary, there is no apparatus and method for preparing localized heterogeneous intelligent composite material by adjusting and controlling input signal to achieve selectivity of different regions and locations in the prior art.

Disclosure of Invention

In order to solve the problem of poor regional selectivity of the surface acoustic wave assisted heterogeneous composite material preparation, the invention provides a device and a method for preparing a localized heterogeneous composite material based on surface wave video regulation.

The technical scheme adopted by the invention comprises the following steps:

a preparation device of a localized heterogeneous composite material regulated and controlled by surface wave time frequency comprises the following steps:

the pair of frequency-variable surface acoustic wave transducers are distributed on the surfaces of two sides of the lithium niobate wafer, the liquid tank is placed on the surface of the middle part of the lithium niobate wafer between the pair of frequency-variable surface acoustic wave transducers, the liquid tank is filled with a mixture of photosensitive liquid, functional particles and a photoinitiator, and the ultraviolet light source is placed under the lithium niobate wafer.

The pair of frequency-variable surface acoustic wave transducers are interdigital transducers, the finger width of the interdigital transducers continuously changes along the finger length direction, and the finger length direction is a straight line or an arc, so that an interdigital transducer and an arc-interdigital transducer are respectively formed.

After a pair of frequency-variable surface acoustic wave transducers are excited by a sinusoidal signal, acoustic waves with different frequencies are generated on the surface of the lithium niobate wafer and in parallel to the finger length direction, the middle area of the lithium niobate wafer between the pair of frequency-variable surface acoustic wave transducers is overlapped to form a surface acoustic standing wave, and the liquid tank is positioned above the area formed by the surface acoustic standing wave.

The ultraviolet light emitted by the ultraviolet light source penetrates through the transparent lithium niobate wafer to irradiate into the liquid tank, and the photosensitive liquid in the liquid tank is subjected to photocuring.

The functional particles include, but are not limited to, metal powder, organic particles, and cells. The photosensitive liquid and the photoinitiator are PEGDA solution with small molecular weight and 2959 photoinitiator respectively.

Secondly, a preparation method of the localized heterogeneous composite material regulated by the surface wave time frequency. Comprises the following steps:

step 1: uniformly mixing functional particles, photosensitive liquid and a photoinitiator, and putting the mixture into a liquid tank through a liquid transfer device;

step 2: inputting frequency f to a pair of variable frequency SAW transducers₁Duration t₁Off time t₂The time difference periodic time frequency regulation sinusoidal signal is provided, so that a pair of frequency-variable surface acoustic wave transducers are excited to form corresponding surface acoustic standing waves, the surface acoustic standing waves are coupled into the liquid tank and then form a localized sound field in the photosensitive liquid, and functional particles in the photosensitive liquid are subjected to the action of the acoustic radiation force of the localized sound field to form stable array distribution in a designed designated area;

and step 3: and opening an ultraviolet light source to cure the photosensitive liquid to finish the manufacture of the localized heterogeneous composite material, wherein the functional particles are fixedly distributed in the localized sound field range in an array shape.

The functional particle material includes but is not limited to metal powder, organic particles and cells.

The periodic time-frequency regulation sinusoidal signals respectively input by a pair of frequency-variable surface acoustic wave transducers have the same period, and each period is t₁With a sinusoidal signal of duration t₂Is connected to zero input signal for a duration t₁The frequency of the internal sinusoidal signal being f₁Furthermore, a time difference t exists between the periodic time-frequency regulation sinusoidal signals of a pair of frequency conversion surface acoustic wave transducers_c。

The functional fine particles are in the form of an arrayTotal width a of distribution₁The total length a is adjusted and controlled by exciting frequency and variable frequency surface wave transducer₂From sinusoidal signal duration t₁And the interval time t₂And (5) adjusting and controlling.

The width position b of the functional fine particles distributed in an array₁Length position b by adjusting and controlling exciting frequency and variable frequency surface wave transducer₂The time difference t between two periodic time-frequency regulated sinusoidal signals_cAnd (5) adjusting and controlling.

The invention generates the corresponding surface acoustic wave by inputting special periodic time-frequency control sinusoidal signals to the frequency conversion surface acoustic wave transducer, thereby realizing the localized sound field distribution in the liquid tank, and realizing the preparation of the corresponding localized heterogeneous composite material by ultraviolet exposure after the arrangement of the driving functional particles.

The invention has the beneficial effects that:

according to the invention, through surface wave time-frequency regulation and control, functional particles in the photosensitive liquid are subjected to the action of sound radiation force of a localized sound field to form stable array-shaped distribution in a designed designated area, so that the localized heterogeneous composite material is prepared, and the preparation diversity of the heterogeneous composite material is enhanced, thereby playing an important role in the fields of cell and macromolecular protein arrangement in biomedicine, flexible touch sensors in wearable electronic equipment and the like.

Drawings

FIG. 1 is a schematic view of a localized heterogeneous composite material preparation apparatus arrangement according to the present invention;

FIG. 2 is a schematic diagram of the characteristic range of standing wave of the surface acoustic wave based on the frequency control of the surface acoustic wave;

FIG. 3 is an input signal based on surface acoustic wave time modulation;

FIG. 4 is a schematic diagram of the characteristic range of standing wave of the acoustic surface based on the time regulation of the acoustic surface wave;

FIG. 5 is a schematic diagram of the arrangement of functional particles of localized heterogeneous composite material based on surface acoustic wave time-frequency modulation.

In the figure: the device comprises a lithium niobate wafer (1), a pair of variable frequency surface acoustic wave transducers (2), a liquid tank (3), an ultraviolet light source (4), a mixture (5) and a localized sound field range (6).

Detailed Description

The present invention will be described in further detail below with reference to the drawings and examples, but the embodiments of the present invention are not limited thereto.

In the experimental preparation apparatus of the present invention shown in fig. 1, a pair of frequency-variable surface acoustic wave transducers 2 are fabricated on both sides of a lithium niobate wafer 1 by an MEMS process, the material of the pair of frequency-variable surface acoustic wave transducers 2 is usually aluminum or gold, the pattern thereof is determined by a mask in the MEMS process, the thickness thereof is determined by a sputtering time, usually 50nm to 200nm, and the finger width of the pair of frequency-variable surface acoustic wave transducers 2 is equal to the finger pitch. The liquid tank 3 is used for containing a mixture 5 of photosensitive liquid, photoinitiator and functional particles, and is placed in the middle of the pair of frequency-variable surface acoustic wave transducers 2, and the material of the liquid tank is usually an organic polymer material with small acoustic impedance, such as polydimethylsiloxane PDMS, so as to reduce the reflection of the acoustic surface waves between the lithium niobate wafer 1 and the liquid tank 3. The ultraviolet light source 4 is placed below the lithium niobate wafer 1.

In order to realize the preparation of the localized heterogeneous composite material, the pair of variable frequency surface acoustic wave transducers 2 can be inclined fingers or arc fingers. If the pair of frequency surface acoustic wave transducers 2 are slanted fingers, as shown in FIG. 1, the pair of frequency interdigital transducers should be symmetrically distributed along the lithium niobate wafer 1. If the pair of frequency surface acoustic wave transducers 2 are arc fingers, the centers of curvature radii of the pair of frequency interdigital transducers 2 should coincide to a point, and are symmetrically distributed about the point. The above structural design can ensure that the surface acoustic waves of different frequencies generated by the pair of frequency conversion surface acoustic wave transducers 2 after excitation can be superposed in the central areas of the pair of frequency conversion surface acoustic wave transducers 2 to form surface acoustic standing waves. The fluid bath 3 should be located above the area where the standing surface acoustic wave is formed. Meanwhile, in order to realize the preparation of the localized heterogeneous composite material, ultraviolet light emitted by the ultraviolet light source 4 can enter the liquid tank through the irradiation of the transparent lithium niobate wafer 1 to carry out photocuring on the photosensitive liquid in the liquid tank.

The preparation process of the localized heterogeneous composite material is divided into three steps:

step 1: the functional particles, the photosensitive liquid and the photoinitiator are uniformly mixed to form a mixture 5, and the mixture is placed into the liquid tank 2 through a liquid transfer device, wherein the functional particles are represented by black dots in figure 2.

The functional particulate material includes, but is not limited to, metal powder, organic particles, and cells.

The maximum size of the functional particles is smaller than 1/10 of the wave length of the surface wave, so that the functional particles are prevented from influencing the sound field distribution. The light-sensitive liquid is selected from the light-sensitive liquid with lower dynamic viscosity as far as possible, such as PEGDA with small molecular weight and the like. After the functional particles, the photosensitive liquid and the photoinitiator are mixed, ultrasonic oscillation is adopted to enable the functional particles to be uniformly dispersed in the photosensitive liquid.

Step 2: and inputting a high-frequency sinusoidal signal with the regulated frequency and time to the variable-frequency surface acoustic wave transducer 2 so as to excite a corresponding surface acoustic standing wave, and forming a localized sound field in the photosensitive liquid after the surface acoustic standing wave is coupled into the liquid tank. The functional particles in the photosensitive liquid are acted by the sound radiation force to form an array-shaped stable arrangement in the localized area 6.

And step 3: and opening the ultraviolet light source to cure the photosensitive liquid to complete the manufacture of the localized heterogeneous composite material. The photosensitive liquid is protected by nitrogen in the curing process, so that the phenomenon that the surface liquid cannot be cured due to the contact of the surface of the photosensitive liquid and oxygen is avoided. The position of the functional particles remains unchanged after curing and still is distributed in the localized acoustic field range 6.

The preparation of the localized heterogeneous composite material of the present invention is described by the following specific examples:

example 1: surface acoustic wave frequency regulation-based surface acoustic wave standing wave distribution range characteristic

FIG. 2 shows a pair of interdigital variable frequency SAW transducers, which can be seen as a top view of the apparatus of FIG. 1 with the fluid bath 3 and mixture 5 removed. According to the principle of the surface acoustic wave transducer, the excitation frequency of the transducer corresponds to the finger width, wherein f is c/4m, c is the sound velocity of the lithium niobate wafer 1 parallel to the finger width direction of the surface acoustic wave transducer 2 with variable frequency, m is the finger width (or finger distance) of a pair of interdigital surface acoustic wave transducers with variable frequency, and the excitation frequency is changed due to the change of the finger width of the surface acoustic wave transducers with variable frequencyHas an adjustment range of f_min<f<f_maxMinimum frequency f_minCorresponding to maximum finger width, similarly, maximum frequency f_maxCorresponding to the minimum finger width.

In the application process, due to the influence of the quality factor of a pair of variable frequency surface acoustic wave transducers, the resonant frequency of the variable frequency surface acoustic wave transducers has a certain bandwidth, so when the specific excitation frequency is input to be f₁(f_min<f₁<f_max) At a specific frequency f₁Corresponding to two sides of the finger width to form a width of a₁Standing surface acoustic waves, as shown by the dotted line in FIG. 2, where a₁An approximation formula a can be adopted₁＝1/n*f/(f_max-f_min) D is calculated. Wherein n is the interdigital logarithm of the variable frequency surface acoustic wave transducer 2, and d is the acoustic aperture, i.e. the total width of the electrode, as shown in fig. 2.

At the same time, the relative position b of the standing surface acoustic wave generated by inputting a specific frequency relative to the surface acoustic wave transducer 2 with variable frequency₁Can be controlled by the excitation frequency f₁B, calculating the design parameters of the variable frequency surface wave transducer, wherein for the variable frequency surface acoustic wave transducer 2 with uniformly-changed finger width, the calculation method is₁＝(f_max-f)/(f_max-f_min)*d。

Example 1 demonstrates that the selectivity of the standing acoustic surface wave in the width direction region and position can be achieved by frequency modulation of the input sinusoidal signal.

Example 2: surface acoustic wave time regulation-based surface acoustic wave standing wave distribution range characteristic

For convenience, the two-dimensional case is analyzed, that is, the surface wave propagation characteristics of the frequency-variable surface acoustic wave transducer 2 along the horizontal centerline section of fig. 2 after the input of the time-modulated sinusoidal signal. The time-modulated input signal is shown in FIG. 3, V₁And V₂Respectively, input signals of a pair of surface acoustic wave transducers. Wherein t is₁Sinusoidal signal in time and zero input signal input at time t2, V₁And V₂The signals are identical in each period but have a relative time difference t_c. The period of the sine signal is corresponding to the frequency conversion of a specific positionThe excitation frequency of the saw surface wave transducer 2. Let t_m(t) is satisfied in order to prevent the signals from overlapping at other positions for the time taken for the surface acoustic wave to propagate from excitation to complete absorption at both sides of the lithium niobate wafer₁+t₂)>t_m. However, in practice, to ensure maximum energy, t₁+t₂Is slightly larger than t_m。

After the time-modulated signal is input, the signal forms two surface acoustic waves from the frequency-variable interdigital transducer 2, as shown in fig. 4, the two surface acoustic waves form a standing wave (within a dotted line region) after propagating in opposite directions (as shown by the black arrow at the upper part in fig. 4), the width of the standing wave region is the same as that of the single traveling wave, and is denoted by a₂＝t₁C, as shown by the dotted line in fig. 4, c is the sound velocity of the lithium niobate wafer 1 in the width direction parallel to the variable frequency surface acoustic wave transducer 2. The standing wave formation region is located at a position b opposite to the center of the lithium niobate wafer 1₂The time difference t of sinusoidal signals of two transducers_cDetermine, in particular, b₂＝t_cC. If t_c0, the two surface waves meet exactly in the middle of the lithium niobate wafer 2, b₂Equal to 0. Meanwhile, the time difference t of the periodic signal can be regulated and controlled_cTo change the position b of the standing wave₂。

Example 2 demonstrates that the selectivity of the standing acoustic surface wave in the length direction region and position can be achieved by time-modulation of the input sinusoidal signal.

Example 3: movement and photocuring of functional particles under the action of sound field

Examples 1 and 2 can calculate the range of the variable frequency surface acoustic wave transducer forming the surface acoustic standing wave under the excitation of the time-frequency regulating signal. After the acoustic surface standing wave is formed on the lithium niobate wafer, the acoustic surface standing wave can enter the photosensitive liquid along Rayleigh angle coupling to form nodes and antinodes with the same period in the photosensitive liquid. However, in practice, the extent of the resulting sound pressure field, which is influenced by propagation loss and the height of the photosensitive liquid surface, may be slightly smaller than the area of the standing surface acoustic wave, and in practice, the calculation may be performed in the time domain by a finite element methodUnder the premise of (1), the sound field distribution p (x, y, z, t) in the photosensitive liquid is obtained in the time domain through piezoelectric coupling and acoustic structure coupling. Then by calculating 1/(t)₁+t₂) (integral p (x, y, z, t) dt) over one input signal period, i.e. t₁+t₂The integration of the above results in the final sound pressure distribution range p (x, y, z).

In the calculated sound pressure distribution range, there are periodic nodes and antinodes, and the distribution period is the same as the period of using the surface acoustic wave. Meanwhile, the sound pressure can apply sound radiation force to the functional particles in the photosensitive liquid, so that the functional particles move to a sound pressure node and finally converge at the node position, namely the period of the final particle arrangement is equal to half of the period of the used surface acoustic wave. If the ultraviolet light source 4 is turned on, the photosensitive liquid is driven by the photoinitiator to be crosslinked, and micromolecules form macromolecular materials, so that the heterogeneous composite material is manufactured by changing liquid into solid and curing. Since the photocuring time is usually short, the functional particles do not move significantly during the photocuring process, and the arrangement position of the final functional particles is the same as that before the photocuring.

Example 4: preparation example of localized heterogeneous composite material based on surface wave time-frequency regulation

Fig. 5 is a top view of a localized heterogeneous composite material manufactured by a pair of interdigital frequency surface acoustic wave transducers 2 after inputting a time-frequency modulated surface wave signal. In this example, the lithium niobate wafer 1 has a length of 5mm and a width of 3mm in this view, and the longitudinal direction thereof coincides with the Y-cut 128 ° X crystal direction of the lithium niobate wafer 1, and has a wave velocity c of 3940m/s corresponding to t_mIt was 1.27. mu.s. The frequency-variable surface acoustic wave transducer 2 is a linear interdigital transducer with the finger length direction, the finger width variation range of the interdigital transducer is 25 mu m to 50 mu m, and the variation range corresponds to f_maxAnd f_min39.4MHz and 19.7MHz, respectively, with a total electrode width d of 2mm and 4 pairs of logarithms (for clarity, the frequency translating saw transducer 2 is shown in fig. 5 only schematically and not to scale).

The frequency of the input frequency of the pair of frequency conversion surface acoustic wave transducers 2 is 30MHz, and the wavelength of the corresponding surface acoustic wave is 131 mu m. Duration t of the sinusoidal signal₁0.33 mus (10 sinusoidal cycles) spaced by a time t₂1 mus (30 sinusoidal cycles) satisfying t₁+t₂Is slightly larger than t_mAnd the input signals of a pair of frequency conversion surface acoustic wave transducers 2 have a time difference t_c0.2 μ s. It can be calculated that it localizes the size a of the sound field distribution range 6₁＝0.6mm，a₂1.3 mm. Position b of the distribution range 6 of the localized sound field₁＝0.96mm，b₂＝0.76mm。

As previously mentioned, the functional particles (black dots) are distributed in an array over the localized acoustic field range 6 at half the wavelength of the input surface acoustic wave, i.e., 66 μm in this example. Under the influence of Rayleigh radiation, the specific arrangement range is slightly smaller than the localized sound field range 6, and the precise calculation can be performed by adopting a finite element method according to the foregoing. Outside the localized sound field range 6, the functional particles are randomly arranged.