Control system and method for non-spherical micro-nano bubble patterning

Abstract

The invention discloses a non-spherical micro-nano bubble patterning control system and method. The system comprises a laser, an acousto-optic deflector, a dichroscope and a microcavity sample chamber, the microcavity sample chamber is filled with liquid, the opening side of the microcavity sample chamber is covered with a substrate, one side of the substrate is provided with a metal film of a nano structure, and the metal film is in contact with the liquid; a laser beam emitted by the laser device sequentially passes through the acousto-optic deflector, the dichroscope and the liquid in the microcavity sample chamber to reach the metal film, so that a non-spherical micro-nano bubble pattern consistent with a preset pattern is formed at the interface of the metal film and the liquid. According to the embodiment of the invention, diversified non-spherical micro-nano bubble patterns can be generated in a submicron-micron size range, the position is accurate and controllable, and the method can be widely applied to the technical field of optics.

Description

Technical Field

[0001] The present invention relates to the field of optical technologies, and in particular, to a control system and method for non-spherical micro-nano bubble patterning. Background Art

[0002] The non-contact controllable formation and precise manipulation of micro-nano bubbles in a liquid environment is one of the key technologies in research fields such as microfluidics, drug delivery, particle self-assembly, and micro-pattern printing. Commonly used methods for generating micro-nano bubbles include the ultrasonic method, the hydrodynamic method, etc. Among them, the ultrasonic method uses the cavitation effect and acoustic streaming phenomenon when ultrasonic waves propagate in a liquid to generate micro-bubbles, which has been applied in the biomedical field. However, the bubble size generated by this method is generally limited to the micron range, and the positions of the bubbles are usually random; the hydrodynamic method relies on the shear force between the liquid and the gas flow at the connection in the microfluidic channel to achieve high-throughput production of micro-bubbles. However, the bubble generation positions are limited to the connections, and the bubbles are immediately washed away with the fluid and cannot be fixed. Moreover, the bubbles generated by the above methods are all spherical, and there are few reports on the generation method of non-spherical micro-nano bubble patterns with simple operation and flexible control up to now. Summary of the Invention

[0003] In view of this, to solve one of the above problems, an object of an embodiment of the present invention is to provide a control system and method for non-spherical micro-nano bubble patterning, which can generate diverse non-spherical micro-nano bubble patterns within the sub-micron to micron size range with precise and controllable positions.

[0004] On the one hand, an embodiment of the present invention provides a control system for non-spherical micro-nano bubble patterning, including a laser, an acousto-optic deflector, a dichroic mirror, and a microcavity sample chamber; the microcavity sample chamber is filled with a liquid, the opening side of the microcavity sample chamber is covered with a substrate, a metal thin film with a nanostructure is arranged on one side of the substrate, and the metal thin film is in contact with the liquid; the laser beam emitted by the laser sequentially passes through the acousto-optic deflector, the dichroic mirror, and the liquid in the microcavity sample chamber to reach the metal thin film, so as to form a non-spherical micro-nano bubble pattern consistent with a preset pattern at the interface between the metal thin film and the liquid.

[0005] Optionally, the size range of the non-spherical micro-nano bubble pattern is 0.4×0.4~100×100 μm 2 。

[0006] Optionally, the metal thin film includes a gold film, and the thickness range of the gold film is 30~80 nm.

[0007] Optionally, the substrate includes a wave plate, and the gold film is deposited on the surface of the wave plate by a thermal evaporation coater and annealed at 300~600 °C for 0.5~3 hours.

[0008] Optionally, the wavelength range of the laser is 800 - 1550 nm, and the power range of the laser is 1 - 100 mW.

[0009] Implementing the embodiments of the present invention includes the following beneficial effects: The laser beam emitted by the laser in this embodiment sequentially passes through an acousto-optic deflector, a dichroic mirror, and the liquid in the microcavity sample chamber to reach the metal film. Utilizing the photothermal effect between the laser and the nanostructured metal film, a non-spherical micro-nano bubble pattern consistent with the preset pattern is generated at the interface between the nanostructured film and the liquid, and its position is accurately controllable.

[0010] On the other hand, the embodiments of the present invention provide a method for controlling non-spherical micro-nano bubble patterning, including:

[0011] Determine the first control parameter of the laser and the second control parameter of the acousto-optic deflector according to the preset pattern; the first control parameter includes the laser power, and the second control parameter includes the step size, frequency, and trajectory of the laser beam movement;

[0012] Turn on the laser and control the laser according to the first control parameter, turn on the acousto-optic deflector and control the acousto-optic deflector according to the second control parameter, so that the laser beam generated by the laser irradiates the metal film according to the preset pattern to form a non-spherical micro-nano bubble pattern.

[0013] Optionally, the laser power is determined by the following method:

[0014] Determine the correlation model between the line width of the non-spherical micro-nano bubble pattern and the laser power;

[0015] Determine the laser power according to the correlation model and the line width of the preset pattern.

[0016] Optionally, the second control parameter is determined by the following method:

[0017] Determine the step size of the laser beam movement according to the line width of the preset pattern;

[0018] Determine the survival time of the hemispherical micro-nano bubble according to the line width of the preset pattern, and determine the frequency of the laser beam movement according to the survival time and the preset pattern size;

[0019] Determine the trajectory of the laser beam movement according to the preset pattern.

[0020] Optionally, the control method further includes:

[0021] Turn on or off the laser at preset time intervals, and control the laser beam to move along several trajectories in sequence through the acousto-optic deflector to form a dynamic display.

[0022] The implementation of the embodiments of the present invention has the following beneficial effects: By controlling parameters such as the power of the laser, the step size, frequency, and trajectory of the laser beam movement through the acousto-optic deflector, the line width, size, and shape of the non-spherical micro-nano bubble pattern are controlled more accurately. Furthermore, non-spherical micro-nano bubble patterns of various shapes are generated within the sub-micron to micron size range, and the position is precisely controllable. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a schematic structural diagram of a control system for non-spherical micro-nano bubble patterning provided by an embodiment of the present invention;

[0024] Figure 2 is a schematic flow chart of the steps of a control method for non-spherical micro-nano bubble patterning provided by an embodiment of the present invention;

[0025] Figure 3 is the design drawing and experimental drawing of a geometric pattern of a single non-spherical micro-nano bubble provided by an embodiment of the present invention;

[0026] Figure 4 is the design drawing and experimental drawing of a combination of non-spherical micro-nano bubble letter patterns provided by an embodiment of the present invention;

[0027] Figure 5 is the design drawing and experimental drawing of the dynamic display of non-spherical micro-nano bubble digital patterns provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. For the step numbers in the following embodiments, they are only set for the convenience of explanation and illustration, and no limitation is imposed on the order between the steps. The execution order of each step in the embodiments can be adaptively adjusted according to the understanding of those skilled in the art.

[0029] As Figure 1 shown, an embodiment of the present invention provides a control system for non-spherical micro-nano bubble patterning, including a laser (1-1), an acousto-optic deflector (1-2), a dichroic mirror (1-3), and a microcavity sample chamber (1-4); the microcavity sample chamber (1-4) is filled with a liquid (1-5), the opening side of the microcavity sample chamber (1-4) is covered with a substrate (1-6), a metal thin film with a nanostructure is provided on one side of the substrate (1-6), and the metal thin film is in contact with the liquid (1-5); the laser beam emitted by the laser (1-1) sequentially passes through the acousto-optic deflector (1-2), the dichroic mirror (1-3), and the liquid (1-5) in the microcavity sample chamber (1-4) to reach the metal thin film, so as to form a non-spherical micro-nano bubble pattern consistent with a preset pattern at the interface between the metal thin film and the liquid (1-5).

[0030] An acousto-optic deflector is used to deflect the angle of a laser beam so that the focusing position of the laser beam can be moved and scanned on the focal plane, with a scanning frequency greater than 60 KHz and a positioning accuracy better than 0.1 nanometers; a dichroic mirror is used to adjust the optical path. The liquid in the microcavity sample chamber includes but is not limited to ultrapure water. A substrate coated with a nanostructured metal film is placed upside down, and the ultrapure water contacts the nanostructured metal film, and the interface thereof is the two-dimensional plane for generating and manipulating non-spherical micro-nano bubble patterns.

[0031] Due to the interaction between the laser beam and the nanostructured metal film on the focal plane, surface plasmon resonance occurs at the "hot spots" on the surface of the nanostructured metal film, causing the light field intensity to increase significantly, which is converted into heat to vaporize the liquid or aggregate the air dissolved in the liquid, thereby forming non-spherical micro-nano bubble patterns with a line width in the sub-micron to micron range.

[0032] It should be noted that the substrate includes but is not limited to glass slides, and the liquid in the microcavity sample chamber includes but is not limited to water or other transparent liquids. The shape of the generated bubbles is not limited to hemispherical, and diverse non-spherical micro-nano bubble patterns can be generated.

[0033] Optionally, the size range of the non-spherical micro-nano bubble patterns is 0.4×0.4~100×100μm 2 。

[0034] The specific size of the preset pattern is determined according to the actual application, and no specific limitation is made in this embodiment. The acousto-optic deflector controls the movement of the laser beam on the focal plane, and its movement range is 100×100μm 2 . The larger the movement range of the laser beam, the larger the size of the non-spherical micro-nano bubble patterns, and its size ranges from 0.4×0.4 to 100×100μm 2 . Due to the laser beam position control accuracy being better than 0.1nm, the position accuracy of the formed non-spherical micro-nano bubble patterns is high.

[0035] Optionally, the metal film includes a gold film, and the thickness range of the gold film is 30~80nm.

[0036] Optionally, the substrate includes a wave plate, and the gold film is deposited on the wave plate using a thermal evaporation coater and annealed at 300~600℃ for 0.5~3 hours.

[0037] The metal film is determined according to the actual application, and no specific limitation is made in this embodiment. The metal film includes but is not limited to a gold film. Specifically, a clean glass slide is prepared, and a gold film with a thickness of 30~80nm is deposited on the glass slide using a thermal evaporation coater, and then thermally annealed at 300~600℃ for 0.5~3h to obtain a glass slide with a nanostructured gold film deposited on its surface.

[0038] Optionally, the wavelength range of the laser is 800~1550nm, and the power range of the laser is 1~100mW.

[0039] The laser is a continuous-wave laser with a wavelength of 800 - 1550 nm and a power of 1 - 100 mW, which is used to irradiate the nanostructured gold film to generate a non-spherical micro-nano bubble pattern by means of the photothermal effect. The specific wavelength of the laser is determined according to the actual application and is not specifically limited in this embodiment.

[0040] Implementing the embodiments of the present invention includes the following beneficial effects: The laser beam emitted by the laser in this embodiment passes through an acousto-optic deflector, a dichroic mirror, and the liquid in the microcavity sample chamber in sequence and reaches the metal film. By using the photothermal effect between the laser and the nanostructured metal film, a non-spherical micro-nano bubble pattern consistent with the preset pattern is generated at the interface between the nanostructured film and the liquid, and its position is accurately controllable.

[0041] Refer to Figure 2 , the embodiments of the present invention provide a method for controlling non-spherical micro-nano bubble patterning, including:

[0042] S100. Determine the first control parameter of the laser and the second control parameter of the acousto-optic deflector according to the preset pattern; the first control parameter includes the laser power, and the second control parameter includes the step size, frequency, and trajectory of the laser beam movement;

[0043] S200. Turn on the laser and control the laser according to the first control parameter, turn on the acousto-optic deflector and control the acousto-optic deflector according to the second control parameter, so that the laser beam generated by the laser irradiates the metal film according to the preset pattern to form a non-spherical micro-nano bubble pattern.

[0044] Specifically, first, design the preset pattern of the non-spherical micro-nano bubbles, and determine the control parameters of the laser and the acousto-optic deflector according to the preset pattern of the non-spherical micro-nano bubbles; then, turn on the laser, set the power of the laser, turn on the acousto-optic deflector, set the step size and movement frequency of the laser beam, and the movement trajectory is along the contour of the designed non-spherical micro-nano bubble pattern. The laser beam generated by the laser irradiates the metal film, and surface plasmon resonance occurs at the "hot spots" on the surface of the metal film, which greatly enhances the light field intensity and is converted into heat to vaporize the liquid in the microcavity sample chamber or aggregate the air dissolved in the liquid, thereby forming a non-spherical micro-nano bubble pattern within the sub-micron to micron size range.

[0045] Optionally, the laser power is determined by the following method:

[0046] Determine the correlation model between the line width of the non-spherical micro-nano bubble pattern and the laser power;

[0047] Determine the laser power according to the correlation model and the line width of the preset pattern.

[0048] The correlation model is determined according to the corresponding relationship between the measured line width and the laser power, which is not specifically limited in this embodiment. The correlation model can be a linear model or a curve model, etc. After the correlation model is determined, the laser power is determined according to the line width of the preset pattern and the correlation model. For example, the line width of the non-spherical micro-nano bubble pattern is controlled by adjusting the power of the laser beam. The greater the laser power, the wider the line width, and the minimum can reach 0.4 μm. The laser power is denoted as P, and the line width is denoted as w, then P ∝ w.

[0049] Optionally, the second control parameter is determined by the following method:

[0050] Determine the step size of the laser beam movement according to the line width of the preset pattern;

[0051] Determine the survival time of the hemispherical micro-nano bubbles according to the line width of the preset pattern, and determine the movement frequency of the laser beam according to the survival time and the preset pattern size;

[0052] Determine the movement trajectory of the laser beam according to the preset pattern.

[0053] Specifically, when determining the line width of the preset pattern, the step size of the laser beam movement should be less than the line width of the non-spherical micro-nano bubble pattern. The step size is denoted as s, then s < w. The survival time of the hemispherical micro-nano bubbles is denoted as T, T ∝ w; the movement frequency is denoted as f, and the total number of movement positions is denoted as n, then f > n·T -1 . The preset pattern first determines the starting point and the ending point, and determines the movement trajectory of the laser beam according to the starting point and the ending point.

[0054] The following is illustrated by several specific embodiments.

[0055] Embodiment 1: Generate a geometric pattern of a single non-spherical micro-nano bubble.

[0056] Prepare a clean glass slide, coat a 40-nm-thick gold film on the glass slide using a thermal evaporation coater, and then perform thermal annealing at 450 °C for 2 hours to obtain a glass slide with a nano-structured gold film coated on its surface.

[0057] Refer to Figure 3 , design regular triangle, square, and circular patterns as shown in (a1 - a3) in Figure 3 . Select a laser with a wavelength of 1064 nm, turn on the laser, and set the laser power to 1.2 mW; turn on the acousto-optic deflector, set the step size of the laser beam movement to 0.2 μm and the movement frequency to 85 KHz, and repeatedly scan one by one along the movement trajectory of the regular triangle pattern shown in (a1) in Figure 3 . Observe a regular triangle micro-nano bubble pattern with a side length of 4 μm and a line width of 0.4 μm as shown in (b1) in Figure 3 . Keep the setting parameters of the laser and the acousto-optic deflector unchanged, and along Figure 3The square pattern trajectory shown in (a2) was repeatedly scanned one by one, and it was observed that as Figure 3 shown in (b2), a square micro-nano bubble pattern with a side length of 6 μm and a line width of 0.4 μm. The laser power was adjusted to 5 mW, and the setting parameters of the acousto-optic deflector remained unchanged. Along Figure 3 the circular pattern trajectory shown in (a3), it was repeatedly scanned one by one, and it was observed that as Figure 3 shown in (b3), an annular micro-nano bubble pattern with a diameter of 8 μm and a line width of 1.7 μm.

[0058] Example 2: Generating a combination of non-spherical micro-nano bubble letter patterns.

[0059] A clean glass slide was prepared, and a gold film with a thickness of 40 nm was deposited on the glass slide using a thermal evaporation coater. Subsequently, it was thermally annealed at 450 °C for 2 hours to obtain a glass slide with a nanostructured gold film deposited on its surface.

[0060] Referring to Figure 4 , a combination of JNU letter patterns as shown in (a) was designed. A laser with a wavelength of 1064 nm was selected, the laser was turned on, and the laser power was set to 2.5 mW; the acousto-optic deflector was turned on, and the laser beam movement step size was set to 0.7 μm and the movement frequency was set to 100 KHz. Along Figure 4 the trajectory of the JNU letter pattern combination shown in (a), it was repeatedly scanned one by one, and it was observed that as Figure 4 shown in (b), a JNU micro-nano bubble letter pattern combination with a line width of 1 μm. Figure 4

[0061] Optionally, the control method further includes:

[0062] Turning on or off the laser at a preset time interval, and controlling the laser beam to move along several trajectories in sequence through the acousto-optic deflector to form a dynamic display.

[0063] It should be noted that the time interval for turning on the laser or the time interval for turning off the laser is determined according to the actual application, and no specific limitation is made in this embodiment, and they can be the same or different. The types of trajectories for the laser beam movement are determined according to the actual application, and no specific limitation is made in this embodiment, and there is at least 1.

[0064] Example 3: Dynamic display of non-spherical micro-nano bubble digital patterns.

[0065] A clean glass slide was prepared, and a gold film with a thickness of 40 nm was deposited on the glass slide using a thermal evaporation coater. Subsequently, it was thermally annealed at 450 °C for 2 hours to obtain a glass slide with a nanostructured gold film deposited on its surface.

[0066] Figure 5 Referring to Figure 5 , a design as Figure 5The digital pattern of numbers 1, 2, 3, 4, and 5 shown in (a). Select a laser with a wavelength of 1064 nm, turn on the laser, and set the laser power to 1.5 mW; turn on the acousto-optic deflector, and set the laser beam moving step size to 0.4 μm and the moving frequency to 90 KHz. First, scan repeatedly one by one along the trajectory of the digital 1 pattern shown in (a), record the time as t = 0 s, and turn off the laser at t = 2 s; turn on the laser at t = 3 s, and scan repeatedly one by one along the trajectory of the digital 2 pattern shown in (a), turn off the laser at t = 5 s; turn on the laser at t = 6 s, and scan repeatedly one by one along the trajectory of the digital 3 pattern shown in (a), turn off the laser at t = 8 s; turn on the laser at t = 9 s, and scan repeatedly one by one along the trajectory of the digital 4 pattern shown in (a), turn off the laser at t = 11 s; turn on the laser at t = 12 s, and scan repeatedly one by one along the trajectory of the digital 5 pattern shown in (a), turn off the laser at t = 14 s. In the above process, the laser beam scans each digital pattern for a duration of 2 s, and there is a 1 s pause in the middle when switching to the next digit. Figure 5 Scan repeatedly one by one along the trajectory of the digital 1 pattern shown in (a), record the time as t = 0 s, and turn off the laser at t = 2 s; turn on the laser at t = 3 s, and scan repeatedly one by one along the trajectory of the digital 2 pattern shown in (a), turn off the laser at t = 5 s; turn on the laser at t = 6 s, and scan repeatedly one by one along the trajectory of the digital 3 pattern shown in (a), turn off the laser at t = 8 s; turn on the laser at t = 9 s, and scan repeatedly one by one along the trajectory of the digital 4 pattern shown in (a), turn off the laser at t = 11 s; turn on the laser at t = 12 s, and scan repeatedly one by one along the trajectory of the digital 5 pattern shown in (a), turn off the laser at t = 14 s. In the above process, the laser beam scans each digital pattern for a duration of 2 s, and there is a 1 s pause in the middle when switching to the next digit. Figure 5 Scan repeatedly one by one along the trajectory of the digital 2 pattern shown in (a), turn off the laser at t = 5 s; turn on the laser at t = 6 s, and scan repeatedly one by one along the trajectory of the digital 3 pattern shown in (a), turn off the laser at t = 8 s; turn on the laser at t = 9 s, and scan repeatedly one by one along the trajectory of the digital 4 pattern shown in (a), turn off the laser at t = 11 s; turn on the laser at t = 12 s, and scan repeatedly one by one along the trajectory of the digital 5 pattern shown in (a), turn off the laser at t = 14 s. In the above process, the laser beam scans each digital pattern for a duration of 2 s, and there is a 1 s pause in the middle when switching to the next digit. Figure 5 Scan repeatedly one by one along the trajectory of the digital 3 pattern shown in (a), turn off the laser at t = 8 s; turn on the laser at t = 9 s, and scan repeatedly one by one along the trajectory of the digital 4 pattern shown in (a), turn off the laser at t = 11 s; turn on the laser at t = 12 s, and scan repeatedly one by one along the trajectory of the digital 5 pattern shown in (a), turn off the laser at t = 14 s. In the above process, the laser beam scans each digital pattern for a duration of 2 s, and there is a 1 s pause in the middle when switching to the next digit. Figure 5 Scan repeatedly one by one along the trajectory of the digital 4 pattern shown in (a), turn off the laser at t = 11 s; turn on the laser at t = 12 s, and scan repeatedly one by one along the trajectory of the digital 5 pattern shown in (a), turn off the laser at t = 14 s. In the above process, the laser beam scans each digital pattern for a duration of 2 s, and there is a 1 s pause in the middle when switching to the next digit. Figure 5 Scan repeatedly one by one along the trajectory of the digital 5 pattern shown in (a), turn off the laser at t = 14 s. In the above process, the laser beam scans each digital pattern for a duration of 2 s, and there is a 1 s pause in the middle when switching to the next digit.

[0067] It can be observed that the dynamic display process of the digital patterns of micro-nano bubbles of 1, 2, 3, 4, and 5 shown in (b), and the line width of the pattern is 0.5 μm. Figure 5 It can be observed that the dynamic display process of the digital patterns of micro-nano bubbles of 1, 2, 3, 4, and 5 shown in (b), and the line width of the pattern is 0.5 μm.

[0068] The above is a specific description of the preferred embodiment of the present invention, but the present invention is not limited to the described embodiments. Those skilled in the art can make various equivalent deformations or substitutions without departing from the spirit of the present invention, and these equivalent deformations or substitutions are all included within the scope defined by the claims of this application.

Claims

1. A control system for non-spherical micro-nano bubble patterning, characterized in that, It includes a laser, an acousto-optic deflector, a dichroic mirror and a microcavity sample chamber; the microcavity sample chamber is filled with a liquid, the open side of the microcavity sample chamber is covered with a substrate, a nanostructured metal thin film is provided on one side of the substrate, and the metal thin film is in contact with the liquid; the laser beam emitted by the laser sequentially passes through the acousto-optic deflector, the dichroic mirror, and the liquid in the microcavity sample chamber to reach the metal thin film, so as to form a non-spherical micro-nano bubble pattern consistent with a preset pattern at the interface between the metal thin film and the liquid.

2. The control system according to claim 1, wherein The size range of the non-spherical micro-nano bubble pattern is 0.4×0.4~100×100 μm 2 .

3. The control system according to claim 1, wherein The metal thin film includes a gold film, and the thickness range of the gold film is 30 - 80 nm.

4. The control system according to claim 1, wherein The substrate includes a wave plate, and the gold film is deposited on the surface of the wave plate by a thermal evaporation coater and annealed at 300 - 600 °C for 0.5 - 3 hours.

5. The control system according to claim 1, characterized in that, The wavelength range of the laser is 800 - 1550 nm, and the power range of the laser is 1 - 100 mW.

6. A control method for non-spherical micro-nano bubble patterning, characterized in that, It includes: Determine the first control parameter of the laser and the second control parameter of the acousto-optic deflector according to the preset pattern; the first control parameter includes the laser power, and the second control parameter includes the step size, frequency and trajectory of the laser beam movement; Turn on the laser and control the laser according to the first control parameter, turn on the acousto-optic deflector and control the acousto-optic deflector according to the second control parameter, so that the laser beam generated by the laser irradiates the metal thin film according to the preset pattern to form a non-spherical micro-nano bubble pattern.

7. The control method according to claim 6, wherein The laser power is determined by the following method: Determine the correlation model between the line width of the non-spherical micro-nano bubble pattern and the laser power; Determine the laser power according to the correlation model and the line width of the preset pattern.

8. The control method according to claim 6, wherein The second control parameter is determined by the following method: Determine the step size of the laser beam movement according to the line width of the preset pattern; Determine the survival time of the hemispherical micro-nano bubble according to the line width of the preset pattern, and determine the frequency of the laser beam movement according to the survival time and the preset pattern size; Determine the trajectory of the laser beam movement according to the preset pattern.

9. The control method according to claim 6, wherein The control method further includes: Turn on or off the laser at preset time intervals, and control the laser beam to move sequentially along several trajectories through the acousto-optic deflector to form a dynamic display.

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