An accurate micro-nano hole device and method based on acousto-optic effect

Abstract

The present application relates to the technical field of pulse laser micro-nano manufacturing. Specifically relates to a kind of accurate micro-nano hole making device and method based on acousto-optic effect, device includes light source system;Acousto-optic off-axis adjustment module is set on the emergent light axis of light source system;Acousto-optic angle deflection module is set on the emergent light axis of acousto-optic off-axis adjustment module;Three-mirror rotating light cylinder is set on the emergent light axis of acousto-optic angle deflection module;Dichroic mirror is set on the emergent light axis of three-mirror rotating light cylinder;Monitoring camera module is set above dichroic mirror, three-axis machining platform is set below dichroic mirror;First radio frequency signal generator is electrically connected with acousto-optic off-axis adjustment module, second radio frequency signal generator is electrically connected with acousto-optic angle deflection module;And host computer control system is electrically connected with monitoring camera module, first radio frequency signal generator and second radio frequency signal generator. Overcome the inertia of traditional galvanometer or rotating mirror and other mechanical structures, slow response and other problems.

Description

Technical Field

[0001] This invention relates to the technical field of pulsed laser micro / nano fabrication, and in particular to a precise micro / nano hole fabrication device and method based on the acousto-optic effect. Background Technology

[0002] Pulsed laser micro / nano-hole fabrication technology, due to its high precision, non-contact nature, and wide applicability, has become an important tool for product processing in fields such as microelectronics, displays, optical devices, and biomedicine. Especially in achieving taper-adjustable micro / nano-holes, pulsed lasers possess unique advantages: firstly, ultrashort pulsed lasers can generate high peak power density on materials, forming non-thermal processing or weakly heat-affected zones, thereby obtaining high-quality hole wall morphologies; secondly, by controlling the laser emission angle or energy distribution, the hole taper can be flexibly adjusted to meet the application requirements of different functional devices for micro-hole taper. Therefore, high-speed, high-resolution, taper-adjustable pulsed laser hole fabrication technology has become an important direction for current research and application.

[0003] In related technologies, patent application number 201120158392.6, entitled "Laser Rotary Cutting and Drilling Device," describes a method that involves sequentially setting two pairs of optical wedges in the beam path. By precisely controlling the relative rotation angle of one pair of wedges, a beam translation offset with variable direction and adjustable size can be synthesized. By controlling the rotation of the other pair of wedges, additional changes in the optical path can be compensated for or introduced. Finally, by driving these wedges to rotate in tandem with a motor, the focused laser spot scans a circular trajectory relative to the workpiece surface. By controlling the diameter of the scanning circle, a tapered hole can be processed. However, this device relies on mechanical rotation drive for the optical wedges, resulting in problems such as high inertia, low adjustment resolution, and slow response speed, which limits processing efficiency and flexibility in hole shape switching.

[0004] For example, in patent application number 202510098278.5, entitled "A Highly Dynamic Five-Axis Laser Processing Device Based on a Double-Wedge," the laser emission direction and spatial position are flexibly adjusted through the joint control of a double-wedge structure and a five-axis motion platform, thereby enabling the fabrication of complex three-dimensional conical or irregular hole structures. This method offers high flexibility and processing freedom, suitable for the fabrication of irregular and non-standard holes. However, such devices are still limited by the shortcomings of traditional mechanical systems. Due to mechanical inertia, they suffer from low resolution in adjusting the hole taper and size at the micro-nano scale, slow processing speed, and poor stability, making it difficult to meet the high-speed and high-precision processing requirements at the micro-nano scale. Furthermore, the multi-coordinate system collaborative control of the five-axis mechanical platform is extremely complex.

[0005] Therefore, when fabricating micro-nano-scale hole structures with adjustable taper, it is necessary to further optimize the method of adjusting the hole taper and size during the hole fabrication process. There is an urgent need for a new pulsed laser micro-nano hole fabrication technology with high resolution, no mechanical inertia, high speed response, and flexible control of the hole taper, in order to solve the problems of slow response speed, low processing accuracy, and insufficient manufacturing stability caused by mechanical drive adjustment. Summary of the Invention

[0006] The purpose of this invention is to provide a precise micro / nano hole fabrication device and method based on acousto-optic effects, which solves the problems of slow response speed, low processing accuracy, and insufficient manufacturing stability caused by the reliance on mechanical drive adjustment in traditional technologies.

[0007] According to one aspect of the present invention, a precise micro / nano aperture fabrication device based on acousto-optic effect is provided, comprising:

[0008] The light source system is used to output the required laser beam;

[0009] An acousto-optic off-axis adjustment module is disposed on the output optical axis of the light source system;

[0010] An acousto-optic angle deflection module is disposed on the output optical axis of the acousto-optic off-axis adjustment module.

[0011] The three-mirror rotating optical tube is disposed on the output optical axis of the acousto-optic angle deflection module;

[0012] A dichroic mirror is disposed on the output optical axis of the three-mirror rotating optical tube;

[0013] A monitoring camera module and a three-axis machining platform are provided, wherein the monitoring camera module is positioned above the dichroic mirror and the three-axis machining platform is positioned below the dichroic mirror;

[0014] A first radio frequency signal generator and a second radio frequency signal generator, wherein the first radio frequency signal generator is electrically connected to the acousto-optic off-axis adjustment module, and the second radio frequency signal generator is electrically connected to the acousto-optic angle deflection module;

[0015] The host computer control system is electrically connected to the monitoring camera module, the first radio frequency signal generator, and the second radio frequency signal generator.

[0016] In one embodiment, the light source system includes a pulsed laser, a beam expander, a half-wave plate, and a mirror module. The beam expander is disposed on the output optical axis of the pulsed laser. The half-wave plate is arranged on the side of the beam expander away from the pulsed laser, and its optical center is located on the output optical axis of the beam expander. The mirror module is disposed on the output optical axis of the half-wave plate.

[0017] In one embodiment, the reflector module includes a first reflector and a second reflector, wherein the center of the mirror surface of the first reflector is disposed on the outgoing optical axis of the half-wave plate, and the normal of the mirror surface of the first reflector is arranged at a 45° angle to the outgoing optical axis of the half-wave plate.

[0018] The center of the second reflector is located on the output optical axis of the first reflector, and the normal of the second reflector is installed at an adjustable angle θ with the output optical axis of the first reflector, so that the output beam from the second reflector can be emitted at a predetermined output angle θ. B1 Reached the first expected position.

[0019] In one embodiment, the acousto-optic off-axis adjustment module includes a first acousto-optic action module, a first aperture, an image-side telecentric correction module, and a leveling mechanism. The first acousto-optic action module includes a first acousto-optic medium, a first ultrasonic transducer, a first sound-absorbing material, and a first electrode.

[0020] The first acousto-optic module is positioned at the first intended location, enabling the emitted light beam from the second reflector to be incident on the central action area of ​​the first acousto-optic medium, so as to receive the light beam from the second reflector at an angle θ. B1The emitted light beam has a first ultrasonic transducer attached to one end of the first acousto-optic medium, and the other end of the first acousto-optic medium is attached to the first sound-absorbing material. A first electrode is attached to the surface of the first ultrasonic transducer and connected to the external drive port of the first acousto-optic module to receive radio frequency signals, causing the light beam to generate +1st, 0th, and other higher orders (±n) diffracted light after passing through the first acousto-optic module. The central action area of ​​the first acousto-optic medium is located at the entrance pupil of the image-side telecentric correction module. A first aperture is placed in the emitted light path of the first acousto-optic module, located after the first acousto-optic medium. The position and size of the aperture of the first aperture are limited to allow only the required +1st order diffracted light to pass through. It blocks 0th-order diffraction light and other useless diffraction-order secondary light; the image-side telecentric correction module is located on the output optical axis of the first acousto-optic module and behind the first aperture, with its entrance pupil aligned with the aperture of the first aperture, so that the +1st-order diffraction angle deflection information generated by the first acousto-optic module is converted into a lateral translation offset relative to the optical axis; the first acousto-optic module, the first aperture, and the image-side telecentric correction module are sequentially aligned with the optical path, and after their relative positions are fixed, they are encapsulated in the same metal housing with an entrance window and an exit window; the leveling mechanism is installed at the bottom of the metal housing and is used to finely adjust the tilt angle of the output beam of the image-side telecentric correction module so that the output beam of the image-side telecentric correction module can be at a predetermined exit angle θ. B2 Reached the second expected position.

[0021] In one embodiment, the acousto-optic angle deflection module includes a second acousto-optic action module, a 4f angle relay module, and a second aperture. The second acousto-optic action module includes a second acousto-optic medium, a second ultrasonic transducer, a second sound-absorbing material, and a second electrode.

[0022] The second acousto-optic module is positioned at the second intended location, enabling the emitted light beam from the image-side telecentric correction module to be incident on the central action area of ​​the second acousto-optic medium, so as to receive the light beam from the image-side telecentric correction module at an angle θ. B2The emitted light beam has a second ultrasonic transducer tightly disposed at one end of the second acousto-optic medium, and the other end of the second acousto-optic medium is attached to the second sound-absorbing material. A second electrode is attached to the surface of the second ultrasonic transducer and connected to the external drive port of the acousto-optic module to receive radio frequency signals, causing the light beam to generate +1, 0, and other higher orders (±n) diffracted light after passing through the second acousto-optic module. The central action area of ​​the second acousto-optic medium is located at the entrance pupil of the 4f-angle relay module. The 4f-angle relay module includes a convex lens L1 and a convex lens L2, both of which are identical biconvex lenses with a focal length of f. The center of the mirror surface of the convex lens L1 is located on the horizontal optical axis of the emitted light from the second acousto-optic module. The distance between the central action area of ​​the second acousto-optic medium and the central action area of ​​the second acousto-optic medium is one focal length f, so that the central action area of ​​the second acousto-optic medium is located at the entrance pupil of the 4f-angle relay module. The center of the mirror surface of the convex lens L2 is set on the horizontal optical axis of the convex lens L1, and the distance between the convex lens L2 and the convex lens L1 is two focal lengths 2f. The second aperture is set at the center between the optical axes of the convex lens L1's exit direction and the convex lens L2's incident direction. The position and size of the aperture of the second aperture are limited to allow only the required +1st order diffraction light to pass through, and block the 0th order diffraction light and other useless diffraction order light. The second acousto-optic action module, the 4f-angle relay module and the second aperture are aligned with the optical path in sequence, and after the relative positions are fixed, they are encapsulated in the same metal housing with an entrance window and an exit window.

[0023] In one embodiment, the precise micro / nano aperture fabrication device based on acousto-optic effect further includes a signal terminal controller, which is electrically connected to the host computer control system. The first radio frequency signal generator includes a first radio frequency generator and a first radio frequency amplifier. The first radio frequency generator is electrically connected to the first radio frequency amplifier, the first radio frequency amplifier is electrically connected to the first electrode, and the first radio frequency generator is electrically connected to the signal terminal controller.

[0024] The second radio frequency generator is electrically connected to the second radio frequency amplifier, the second radio frequency amplifier is connected to the second electrode, and the second radio frequency generator is electrically connected to the signal terminal controller.

[0025] In one embodiment, the three-mirror rotating optical tube includes a first polarizing prism, a second polarizing prism, a total reflection mirror, and a high-speed rotation drive device. The mirror centers of the first and second polarizing prisms are located on the output optical axis of the acousto-optic angle deflection module. The first polarizing prism rotates at a predetermined angle θ. P The second polarizing prism is fixedly installed inside the three-mirror rotating optical tube, and is positioned at a predetermined angle -θ.P The total reflection mirror is fixedly installed on the output optical axis of the first polarizing prism in an axially symmetrical manner. The total reflection mirror is located between the first polarizing prism and the second polarizing prism and is fixedly installed at the bottom of the three-mirror rotating optical tube. The high-speed rotation drive device is installed on the outside of the three-mirror rotating optical tube.

[0026] In one embodiment, the precise micro / nano aperture fabrication device based on acousto-optic effect further includes a Z-axis focusing module, which is disposed between the dichroic mirror and the triaxial processing platform and is located on the outgoing optical axis of the dichroic mirror.

[0027] In one embodiment, the three-axis machining platform includes a fixture and a three-axis motion module. The fixture is disposed on the three-axis motion module and is used to clamp and position the sample to be processed. The three-axis motion module is used to drive the sample to be processed to move in at least one of the horizontal transverse, horizontal longitudinal and vertical directions.

[0028] According to another aspect of the present invention, a method for fabricating pores based on the above-described acousto-optic effect-based precision micro / nano pore fabrication device is provided, comprising the following steps:

[0029] S10. Reset the acousto-optic precision micro / nano hole fabrication device, turn on the monitoring camera module and its light source, and adjust the pulsed laser parameters.

[0030] S20. Fix the sample to be processed on the three-axis machining platform, and send a control signal to the signal terminal controller through the host computer control system to move the three-axis machining platform to the camera center of the monitoring camera module.

[0031] S30. Load the preset target conical hole model into the host computer control system and send control commands to the signal terminal controller. After receiving the commands, the signal terminal controller sends control signals to the first radio frequency signal generator, the second radio frequency signal generator, the high-speed rotation drive device and the Z-axis focusing module.

[0032] S40, the acousto-optic off-axis adjustment module receives control signals and adjusts the lateral translation offset of the beam relative to the optical axis; the acousto-optic angle deflection module receives control signals and adjusts the angle of the beam incident on the rotating optical tube of the three mirrors; the Z-axis focusing module receives control signals and adjusts the depth of focus.

[0033] S50: The high-speed rotation drive device receives the control signal and drives the three-mirror rotating optical tube to rotate at high speed. The emitted light beam is reflected by the dichroic mirror onto the workpiece at the three-axis machining platform and is then rotated around the optical axis at high speed.

[0034] S60. The monitoring camera module captures the processing footage and uploads it to the host computer control system. It compares the footage with a preset target conical hole model to obtain error information regarding the hole diameter, cone shape, and hole depth. Based on this error, a feedback command is generated and sent to the terminal signal controller, forming a closed-loop control. Implementing this embodiment of the invention will have the following beneficial effects:

[0035] In this embodiment, the precise micro / nano hole-making device based on the acousto-optic effect operates by mounting the sample to be processed onto a triaxial processing platform. Then, the light source system is activated, outputting a laser beam to the acousto-optic off-axis adjustment module. This module utilizes the acousto-optic effect to control the angle deflection of the incident laser beam, converting the angle deflection information into a lateral translational offset relative to the optical axis, thereby controlling the taper of the hole. Furthermore, the acousto-optic angle deflection module similarly uses the acousto-optic effect to control the angle deflection of the incident laser beam, linearly mapping the beam's angle and position information to the rotating optical tube of the three mirrors, thereby controlling the hole size. All of the above processes fully utilize the interaction between sound waves and light waves in the acousto-optic medium, without involving the movement of any mechanical parts. Its response speed can reach sub-microsecond or even nanosecond levels, thus overcoming the problems of large inertia, slow response, and susceptibility to overshoot and vibration inherent in traditional mechanical structures such as galvanometers or rotating mirrors, ensuring precise controllability during high-frequency scanning or high-speed hole-making.

[0036] Furthermore, the adjustment of the beam by the acousto-optic off-axis adjustment module and the acousto-optic angle deflection module is driven by the radio frequency signal sources generated by the first radio frequency signal generator and the second radio frequency signal generator, respectively. The adjustment accuracy is determined by the resolution of the radio frequency signal, thus achieving extremely high translation resolution and angle resolution control. Moreover, the adjustment parameters of the hole taper and aperture are determined by the frequency of the radio frequency signal, thus avoiding the problems of hole shape distortion, low taper control resolution and poor consistency caused by inertia and vibration under traditional mechanical control.

[0037] Furthermore, the monitoring camera module can acquire images of the hole-making process in real time and upload them to the host computer control system. The host computer control system compares the actual hole shape with the preset target model, extracts the deviation information, generates corresponding feedback instructions, and adjusts the driving parameters of the control hole in real time, thereby realizing closed-loop adaptive adjustment. This mechanism can automatically correct the hole shape deviation under environmental disturbance conditions, ensuring that the final hole shape target design is highly consistent, and significantly improving the stability and robustness of the processing. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the structure of a precision micro / nano hole fabrication device based on the acousto-optic effect according to an embodiment;

[0039] Figure 2 This is a schematic diagram illustrating the principle of an acoustic-optical off-axis adjustment module according to one embodiment;

[0040] Figure 3 This is a schematic diagram of the principle of an acousto-optic angle deflection module according to one embodiment;

[0041] Figure 4 This is a schematic diagram of the cooperative structure of a reflector module and a first acousto-optic module according to one embodiment;

[0042] Figure 5 This is a schematic diagram of the structure of the second acousto-optic module in one embodiment;

[0043] Figure 6 This is a schematic diagram illustrating the principle of adjusting the off-axis offset of a three-mirror rotating optical tube according to an embodiment.

[0044] Figure 7 A schematic diagram of the internal optical path principle for adjusting the incident angle using a three-mirror rotating optical tube;

[0045] Figure 8a A schematic diagram illustrating the microscopic principle of adjusting the hole taper and hole diameter when the off-axis offset d1 is input;

[0046] Figure 8b A schematic diagram illustrating the microscopic principle of adjusting the cone shape and aperture of the hole when the deflection angle θ1 is input;

[0047] Figure 8c A schematic diagram illustrating the microscopic principle of adjusting the cone shape and aperture of a hole when both off-axis offset d2 and deflection angle θ2 are simultaneously input.

[0048] Figure 9 This is a schematic diagram illustrating the processing principle of forming tapered micro- and nano-pores on a sample to be processed, as shown in one embodiment.

[0049] Figure 10 This is a flowchart illustrating the steps of a method for fabricating a precise micro / nano aperture based on an acousto-optic effect according to an embodiment.

[0050] in:

[0051] 1. Pulsed laser; 2. Beam expander system; 3. Half-wave plate; 4. Mirror module; 41. First mirror; 42. Second mirror; 5. Acousto-optic off-axis adjustment module; 51. First acousto-optic interaction module; 52. Image-side telecentric correction module; 53. First aperture; 54. Leveling mechanism; 511. First acousto-optic medium; 512. First ultrasonic transducer; 513. First sound-absorbing material; 514. First electrode; 6. Acousto-optic angle deflection module; 61. Second acousto-optic interaction module; 62. 4f angle relay module; 63. Second aperture; 611. Second acousto-optic medium; 612. Second ultrasonic transducer. 613. Transducer; 614. Second sound-absorbing material; 615. Second electrode; 7. Three-mirror rotating optical tube; 71. First polarizing prism; 72. Second polarizing prism; 73. Total reflection mirror; 74. High-speed rotating transmission device; 8. Monitoring camera module; 9. Dichroic mirror; 10. Z-axis focusing module; 11. Host computer control system; 12. Signal terminal controller; 13. First radio frequency signal generator; 131. First radio frequency amplifier; 132. First radio frequency generator; 14. Second radio frequency signal generator; 141. Second radio frequency amplifier; 142. Second radio frequency generator; 15. Three-axis machining platform. Detailed Implementation

[0052] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0053] It should be noted that when a component is said to be "fixed to" another component, it can be directly attached to the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0054] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0055] Please refer to Figures 1-9An embodiment of a precision micro / nano hole fabrication device based on acousto-optic effect includes: a light source system, an acousto-optic off-axis adjustment module 5, an acousto-optic angle deflection module 6, a three-mirror rotating light tube 7, a dichroic mirror 9, a monitoring camera module 8, a three-axis processing platform 15, a first radio frequency signal generator 13, a second radio frequency signal generator 14, and a host computer control system 11.

[0056] The light source system outputs the required laser beam. This laser beam acts on the sample to be processed, creating micro- and nano-scale pore structures of the desired shape and size.

[0057] The acousto-optic off-axis adjustment module 5 is mounted on the output optical axis of the light source system; the acousto-optic angle deflection module 6 is mounted on the output optical axis of the acousto-optic off-axis adjustment module 5; the three-mirror rotating light tube 7 is mounted on the output optical axis of the acousto-optic angle deflection module 6; the dichroic mirror 9 is mounted on the output optical axis of the three-mirror rotating light tube 7; the monitoring camera module 8 is mounted above the dichroic mirror 9; and the three-axis machining platform 15 is mounted below the dichroic mirror 9. The first radio frequency signal generator 13 is electrically connected to the acousto-optic off-axis adjustment module 5, and the second radio frequency signal generator 14 is electrically connected to the acousto-optic angle deflection module 6. The host computer control system 11 is electrically connected to the monitoring camera module 8, the first radio frequency signal generator 13, and the second radio frequency signal generator 14.

[0058] In summary, implementing this embodiment will achieve the following technical effects: When the acousto-optic precision micro / nano hole-making device of this embodiment is working, the sample to be processed is installed on the triaxial processing platform 15, and then the light source system is started. The light source system outputs a laser beam to the acousto-optic off-axis adjustment module 5. The acousto-optic off-axis adjustment module 5 uses the acousto-optic effect to control the angle deflection of the incident laser and converts the angle deflection information into a lateral translation offset relative to the optical axis, thereby controlling the taper of the hole. Furthermore, the acousto-optic angle deflection module 6 similarly uses the acousto-optic effect to control the angle deflection of the incident laser and linearly maps the angle and position information of the beam to the three-mirror rotating optical tube 7, thereby controlling the aperture size. The above processes all utilize the interaction between sound waves and light waves in the acousto-optic medium without involving the movement of any mechanical parts. Its response speed can reach the sub-microsecond or even nanosecond level of fast response. Therefore, it overcomes the problems of large inertia, slow response, and easy overshoot and vibration of traditional mechanical structures such as galvanometers or rotating mirrors, ensuring precise controllability during high-frequency scanning or high-speed hole making.

[0059] Furthermore, the adjustment of the beam by the acousto-optic off-axis adjustment module 5 and the acousto-optic angle deflection module 6 is driven by the radio frequency signal sources generated by the first radio frequency signal generator 13 and the second radio frequency signal generator 14, respectively. The adjustment accuracy is determined by the resolution of the radio frequency signal, so extremely high translation resolution and angle resolution control can be achieved. Moreover, the adjustment parameters of the hole taper and the hole diameter are determined by the frequency of the radio frequency signal, thus avoiding the problems of hole shape distortion, low taper control resolution and poor consistency caused by inertia and vibration under traditional mechanical control.

[0060] Furthermore, with the help of the monitoring camera module 8, images of the hole-making process can be acquired in real time and uploaded to the host computer control system 11. The host computer control system 11 compares the actual hole shape with the preset target model, extracts the deviation information, generates corresponding feedback instructions, and adjusts the driving parameters of the control hole in real time, thereby realizing closed-loop adaptive adjustment. This mechanism can automatically correct the hole shape deviation under environmental disturbance conditions, ensuring that the final hole shape target design is highly consistent, and significantly improving the stability and robustness of the processing.

[0061] Please see Figure 1 In one embodiment, the light source system includes a pulsed laser 1, a beam expander 2, a half-wave plate 3, and a mirror module 4. The beam expander 2 is disposed on the output optical axis of the pulsed laser 1. The half-wave plate 3 is arranged on the side of the beam expander 2 away from the pulsed laser 1, and the optical center of the half-wave plate 3 is located on the output optical axis of the beam expander 2. The mirror module 4 is disposed on the output optical axis of the half-wave plate 3.

[0062] In actual operation, the technical parameters of the pulsed laser 1 are first adjusted at the start of processing to emit a laser beam. The beam expansion system 2 is used to expand and collimate the original pulsed laser beam. The expansion factor of the beam expansion system 2 is adjusted so that the diameter of the collimated laser beam reaches 80% of the aperture of the acousto-optic off-axis adjustment module 5. Then, the fast axis direction of the half-wave plate 3 is adjusted to the horizontal direction so that the incident linearly polarized light is adjusted to a horizontally polarized state, ensuring that the laser beam entering the subsequent optical device after passing through the half-wave plate 3 is horizontally polarized light.

[0063] In one embodiment, the reflector module 4 includes a first reflector 41 and a second reflector 42. The center of the mirror surface of the first reflector 41 is located on the outgoing optical axis of the half-wave plate 3, and the normal of the mirror surface of the first reflector 41 is arranged at a 45° angle to the outgoing optical axis of the half-wave plate 3.

[0064] The center of the mirror surface of the second reflector 42 is located on the output optical axis of the first reflector 41. The normal of the mirror surface of the second reflector 42 is installed at an adjustable angle θ with the output optical axis of the first reflector 41, so that the output beam of the second reflector 42 can be emitted at a predetermined output angle θ. B1The laser beam reaches the first expected position. After passing through the half-wave plate 3, it is incident on the first reflecting mirror 41. The first reflecting mirror 41 reflects the beam downwards at a 90° angle to the second reflecting mirror 42. The direction of the second reflecting mirror 42 is adjusted so that the beam can be incident on the central action area of ​​the first acousto-optic medium 511. This ensures the transmission quality and effect of the laser beam and improves the utilization rate of the laser beam.

[0065] Please see Figure 2 In one embodiment, the acoustic-optic off-axis adjustment module 5 includes a first acoustic-optic action module 51, a first aperture 53, an image-side telecentric correction module 52, and a leveling mechanism 54. The first acoustic-optic action module 51 includes a first acoustic-optic medium 511, a first ultrasonic transducer 512, a first sound-absorbing material 513, and a first electrode 514.

[0066] The first acousto-optic module 51 is positioned at a first predetermined location, enabling the emitted light beam from the second reflector 42 to be incident on the central action area of ​​the first acousto-optic medium 511, so as to receive the light beam from the second reflector 42 at an angle θ. B1 The emitted light beam has a first ultrasonic transducer 512 attached to one end of a first acousto-optic medium 511, and a first sound-absorbing material 513 attached to the other end of the first acousto-optic medium 511. A first electrode 514 is attached to the surface of the first ultrasonic transducer 512 and is connected to the external drive port of the first acousto-optic module 51 to receive radio frequency electrical signals so that the light beam generates +1, 0, and other higher orders ±n order diffracted light after passing through the first acousto-optic module 51. The central action area of ​​the first acousto-optic medium 511 is located at the entrance pupil of the image-side telecentric correction module 52. A first aperture 53 is placed in the emitted light path of the first acousto-optic module 51 and is located after the first acousto-optic medium 511. The position and size of the aperture of the first aperture 53 are limited to allow only the required +1 order diffracted light. The diffracted light passes through, while blocking the 0th order diffracted light and other useless diffracted order light; the image-side telecentric correction module 52 is located on the output optical axis of the first acousto-optic module 51 and is located after the first aperture 53. Its entrance pupil position is aligned with the light-transmitting aperture of the first aperture 53, so that the angle deflection information of the +1st order diffracted light generated by the first acousto-optic module 51 is converted into a lateral translation offset relative to the optical axis; the first acousto-optic module 51, the first aperture 53, and the image-side telecentric correction module 52 are aligned with the optical path in sequence, and after fixing their relative positions, they are encapsulated in the same metal housing with an entrance window and an exit window; the leveling mechanism 54 is installed at the bottom of the metal housing and is used to finely adjust the tilt angle of the output beam of the image-side telecentric correction module 52 so that the output beam of the image-side telecentric correction module 52 can be at a predetermined exit angle θ. B2 Reached the second expected position.

[0067] For example, in a specific processing scenario, the first ultrasonic transducer 512 converts the received radio frequency electrical signal into ultrasonic waves and couples the ultrasonic waves into the interior of the first acousto-optic medium 511, causing the refractive index of the first acousto-optic medium 511 to change periodically, thereby forming a periodically changing dynamic grating. After the incident beam enters the central action area of ​​the first acousto-optic medium 511, it interacts with the ultrasonic waves, and Bragg diffraction occurs, producing +1st order, 0th order and other higher orders ±n order diffracted light. The 0th order diffracted light maintains its original direction of transmission, while the deflection angle of the +1st order diffracted light is proportional to the frequency of the radio frequency electrical signal. By changing the frequency of the radio frequency signal, the diffraction angle of the beam can be controlled.

[0068] In this process, the amplitude of the radio frequency (RF) signal determines the diffraction efficiency of the diffracted beam. Changing the frequency of the RF signal linearly changes the deflection angle of the diffracted beam. The higher the frequency resolution of the RF signal, the higher the accuracy of the diffraction angle control. Let the frequency of the RF signal be f1, and the speed of sound in the acousto-optic medium be V. a1 The wavelength of the light beam is λ1, and the diffraction angle is θ. y1 Then sin(θ) y1 )=λ1f1 / V a1 .

[0069] Furthermore, the propagation speed of sound waves in the acousto-optic medium is positively correlated with the response time of the light beam. The first aperture 53 is placed in the output light path of the first acousto-optic module 51. After the diffracted light passes through the first acousto-optic module 51, it arrives at the first aperture 53. The first aperture 53 causes the 0th order diffracted light to be spatially separated from the +1st order diffracted light and other higher order ±n order diffracted light during propagation, allowing only the +1st order diffracted light to pass through. After passing through the first aperture 53, the +1st order diffracted light arrives at the image-side telecentric correction module 52, where the light beam is corrected to be an output beam parallel to the optical axis, achieving parallel output of the +1st order diffracted light. This converts the angle deflection information of the +1st order diffracted light generated by the first acousto-optic module 51 into a lateral translation offset relative to the optical axis.

[0070] Please see Figure 3 In one embodiment, the acousto-optic angle deflection module 6 includes a second acousto-optic action module 61, a 4f angle relay module 62, and a second aperture 63. The second acousto-optic action module 61 includes a second acousto-optic medium 611, a second ultrasonic transducer 612, a second sound-absorbing material 613, and a second electrode 614.

[0071] The second acousto-optic module 61 is positioned at the second intended location, enabling the emitted light beam from the image-side telecentric correction module 52 to be incident on the central action area of ​​the second acousto-optic medium 611, so as to receive the light beam from the image-side telecentric correction module 52 at an angle θ. B2The emitted light beam has a second ultrasonic transducer 612 tightly disposed at one end of a second acousto-optic medium 611, and a second sound-absorbing material 613 adhered to the other end of the second acousto-optic medium 611. A second electrode 614 is attached to the surface of the second ultrasonic transducer 612 and is connected to the external drive port of the acousto-optic module to receive radio frequency electrical signals so that the light beam generates +1, 0, and other higher orders ±n diffracted light after passing through the second acousto-optic module 61. The central action area of ​​the second acousto-optic medium 611 is located at the entrance pupil of the 4f-angle relay module 62. The 4f-angle relay module 62 includes a convex lens L1 and a convex lens L2, which are identical biconvex lenses with a focal length of f. The center of the mirror surface of the convex lens L1 is located at the exit horizontal plane of the second acousto-optic module 61. On the optical axis, and with a distance of one focal length f from the central working area of ​​the second acousto-optic medium 611, so that the central working area of ​​the second acousto-optic medium 611 is located at the entrance pupil of the 4f-angle relay module 62, the center of the mirror surface of the convex lens L2 is set on the horizontal optical axis of the exit of the convex lens L1, and with a distance of two focal lengths 2f from the convex lens L1, the second aperture 63 is set at the center between the optical axes of the exit direction of the convex lens L1 and the incident direction of the convex lens L2, and the position and size of the light aperture of the second aperture 63 are limited to allow only the required +1 order diffraction light to pass through, and block the 0th order diffraction light and other useless diffraction order light; the second acousto-optic module 61, the 4f-angle relay module 62 and the second aperture 63 are aligned with the optical path in sequence, and after the relative positions are fixed, they are encapsulated in the same metal housing with an entrance window and an exit window.

[0072] In actual processing and use, the second ultrasonic transducer 612 converts the received radio frequency electrical signal into ultrasonic waves and couples the ultrasonic waves into the interior of the second acousto-optic medium 611, causing the refractive index of the second acousto-optic medium 611 to change periodically, thereby forming a periodically changing dynamic grating. After the incident beam enters the central action area of ​​the second acousto-optic medium 611, it interacts with the ultrasonic waves and causes Bragg diffraction, producing +1st order, 0th order and other higher orders ±n order diffracted light. Among them, the 0th order diffracted light maintains its original direction of transmission, while the deflection angle of the +1st order diffracted light is proportional to the frequency of the radio frequency electrical signal. By changing the frequency of the radio frequency signal, the diffraction angle of the beam is controlled.

[0073] In this process, the amplitude of the radio frequency (RF) signal determines the diffraction efficiency of the diffracted beam. Changing the frequency of the RF signal linearly changes the deflection angle of the diffracted beam. The higher the frequency resolution of the RF signal, the higher the accuracy of the diffraction angle control. Let the frequency of the RF signal be f2, and the speed of sound in the acousto-optic medium be V. a2 The wavelength of the light beam is λ2, and the diffraction angle is θ. y2 Then sin(θ) y2 )=λ2f2 / V a2Furthermore, the propagation speed of sound waves in the acousto-optic medium is positively correlated with the response time of the light beam. After being transmitted through the convex lens L1, the diffracted light reaches the second aperture 63. The second aperture 63 causes the 0th order diffracted light to be spatially separated from the +1st order diffracted light and other higher-order ±n order diffracted light during propagation, allowing only the +1st order diffracted light to pass through. After passing through the convex lens L2, the +1st order diffracted light is transmitted to the three-mirror rotating optical tube 7.

[0074] Please see Figure 4 and Figure 5 In one embodiment, the precise micro-nano aperture fabrication device based on acousto-optic effect further includes a signal terminal controller 12, which is electrically connected to the host computer control system 11. The first radio frequency signal generator 13 includes a first radio frequency generator 132 and a first radio frequency amplifier 131, which are electrically connected to each other. The first radio frequency amplifier 131 is electrically connected to the first electrode 514, and the first radio frequency generator 132 is electrically connected to the signal terminal controller 12.

[0075] The second radio frequency generator 142 is electrically connected to the second radio frequency amplifier 141, the second radio frequency amplifier 141 is connected to the second electrode 614, and the second radio frequency generator 142 is electrically connected to the signal terminal controller 12.

[0076] During operation, the first RF amplifier 131 is used to input RF electrical signals to the first electrode 514, and the second RF amplifier 141 is used to input RF electrical signals to the second electrode 614. The frequency of the RF signal can be adjusted by the signal terminal controller 12, thereby linearly changing the deflection angle of the diffracted beam. The higher the frequency resolution of the RF signal, the higher the diffraction angle control resolution, and the higher the control aperture cone and aperture resolution.

[0077] Please see Figure 6 and Figure 7 In one embodiment, the three-mirror rotating optical tube 7 includes a first polarizing prism 71, a second polarizing prism 72, a total reflection mirror 73, and a high-speed rotation drive device. The mirror centers of the first polarizing prism 71 and the second polarizing prism 72 are located on the output optical axis of the acousto-optic angle deflection module 6. The first polarizing prism 71 rotates at a predetermined angle θ. P The second polarizing prism 72 is fixedly installed inside the three-mirror rotating optical tube 7 at a predetermined angle -θ. P The total reflection mirror 73 is located between the first polarizing prism 71 and the second polarizing prism 72 and is fixedly installed at the bottom of the three-mirror rotating optical tube 7. The high-speed rotation drive device is installed on the outside of the three-mirror rotating optical tube 7.

[0078] It should be noted that, Figure 6 In this context, d represents the off-axis offset.

[0079] Figure 8a This diagram illustrates the microscopic principle of adjusting the cone shape and diameter of a hole when an off-axis offset of d1 is input. ① shows the initial processing state of the sample to be processed, and ② shows the processing state of the sample to be processed after the off-axis offset of d1 is input.

[0080] Figure 8b This diagram illustrates the microscopic principle of controlling the cone shape and aperture of a hole when the deflection angle θ1 is input. ① shows the initial processing state of the sample to be processed, and ③ shows the processing state of the sample to be processed after the deflection angle θ1 is input.

[0081] Figure 8c This diagram illustrates the microscopic principle of controlling the cone shape and aperture of a hole when both off-axis offset d2 and deflection angle θ2 are simultaneously input. ① shows the initial processing state of the sample to be processed, and ④ shows the processing state of the sample after simultaneously inputting the off-axis offset d2 and deflection angle θ2.

[0082] In actual operation, the signal terminal controller 12 sends control commands to the high-speed rotation drive device to control the high-speed rotation of the three-mirror rotating optical tube 7. This causes the outgoing beam of the three-mirror rotating optical tube 7 to be rapidly spun. The +1st order diffracted light enters the three-mirror rotating optical tube 7 and is then rotated at high speed before entering the dichroic mirror 9. The center of the mirror surface of the dichroic mirror 9 is mounted on the outgoing optical axis of the three-mirror rotating optical tube 7, and the normal of the mirror surface of the dichroic mirror 9 is installed at a 45° angle to the outgoing optical axis of the three-mirror rotating optical tube 7.

[0083] In one embodiment, the precise micro / nano hole-making device based on the acousto-optic effect further includes a Z-axis focusing module 10. The Z-axis focusing module 10 is disposed between the dichroic mirror 9 and the triaxial processing platform 15, and is located on the output optical axis of the dichroic mirror 9. During operation, the dichroic mirror 9 is used to reflect the output rotating laser beam of the triaxial rotating optical tube 7 and transmit the illumination source of the monitoring camera module 8. The high-speed rotating +1st order diffracted light enters the Z-axis focusing module 10 after being reflected by the dichroic mirror 9. The signal terminal controller 12 sends control commands to the Z-axis focusing module 10 to control the Z-axis focal depth, thereby adjusting the hole-making depth. After being focused by the Z-axis focusing module 10, the beam finally reaches the target position on the sample to be processed on the triaxial processing platform 15. The focused beam is then rapidly rotary-cut at the target position to form a tapered micro / nano hole.

[0084] Figure 9 The diagram shows the processing principle of forming tapered micro-nano holes in the sample to be processed; where h is the change in hole depth after processing.

[0085] The monitoring camera module 8 is located directly above the dichroic mirror 9 and is coaxially aligned with the outgoing optical axis of the dichroic mirror 9, so that the lens of the monitoring camera module 8 is vertically downward and aligned with the dichroic mirror 9. During the processing, the monitoring camera module 8 can capture the processing scene in real time and transmit it back to the host computer control system 11 through the signal terminal controller 12, so as to optimize and control the processing parameters in real time to obtain the best tapered hole processing quality.

[0086] In one embodiment, the three-axis machining platform 15 includes a fixture and a three-axis motion module. The fixture is disposed on the three-axis motion module and is used to clamp and position the sample to be processed. The three-axis motion module is used to drive the sample to be processed to move in at least one of the horizontal transverse, horizontal longitudinal and vertical directions.

[0087] The fixture is used to clamp and position the sample to be processed. For example, the fixture can use at least one of the following methods to clamp or release the sample: mechanical clamping, negative pressure adsorption, etc., whichever is required. The three-axis motion module moves the sample to be processed flexibly in space to adapt to the angle of the laser beam, so as to process the micro-nano holes with the required taper, thereby improving the flexibility and accuracy of the processing.

[0088] In this application, the signal terminal controller 12 is electrically connected to the first radio frequency signal generator 13, the second radio frequency signal generator 14, the high-speed rotary transmission device 74, the Z-axis focusing module 10, the three-axis machining platform 15, the pulsed laser 1, and the host computer control system 11. In specific applications, the signal terminal controller 12 receives instructions issued by the host computer control system 11 and can store them in the program memory for offline operation. It can also receive feedback signals from the first radio frequency signal generator 13, the second radio frequency signal generator 14, the Z-axis focusing module 10, the three-axis machining platform 15, and the monitoring camera module 8.

[0089] The host computer control system 11 is connected to the signal terminal controller 12. The host computer control system 11 is used to issue control commands to the first radio frequency signal generator 13, the second radio frequency signal generator 14, the high-speed rotary transmission device 74, the Z-axis focusing module 10, the three-axis machining platform 15, and the pulse laser 1.

[0090] In one embodiment, by finely adjusting the tilt angle of the leveling mechanism 54, the incident angle θ of the light beam incident on the central active area of ​​the second acousto-optic medium 611 is adjusted. B2 Satisfying the Bragg condition, let the wavelength of the beam emitted by pulsed laser 1 in vacuum be λ2, the frequency of the radio frequency signal input to the second radio frequency signal generator 14 be f2, the refractive index of the second acousto-optic medium 611 be n2, and the propagation speed of sound waves in the second acousto-optic medium 611 be V2. Then sin(θ) B2 =λ2f2 / (2n2V2).

[0091] In another embodiment, when the incident angle θ of the light beam incident on the central active region of the second acousto-optic medium 611 B2 After satisfying the Bragg condition, the angle of the second reflector 42 of the reflector module 4 is finely adjusted to make the incident angle θ of the light beam incident on the central action area of ​​the first acousto-optic medium 511. B1 Satisfying the Bragg condition, let λ1 be the wavelength of the beam emitted by pulsed laser 1 in vacuum, f1 be the frequency of the radio frequency signal input to the first radio frequency signal generator 13, n1 be the refractive index of the first acousto-optic medium 511, and V1 be the propagation speed of sound waves within the first acousto-optic medium 511. Let sin(θ) B1 =λ1f1 / (2n1V1).

[0092] In another embodiment, the central working area of ​​the second acousto-optic medium 611 in the acousto-optic angle deflection module 6 is located at the front focal plane of the convex lens L1, and the center of the mirror surface of the first polarizing prism 71 is located at the rear focal plane of the convex lens L2, so that the acousto-optic angle deflection module 6 is located on the entrance pupil side of the 4f angle relay module 62, the first polarizing prism 71 is located on the exit pupil side of the 4f angle relay module 62, and the entrance pupil side and the exit pupil side form an inverted relay relationship with a magnification of -1, so that the lateral position and propagation angle of the beam on the exit pupil side are respectively reversed to the lateral position and propagation angle of the corresponding beam on the entrance pupil side. In practical applications, the position and angle information of the +1st order diffracted light generated by the second acousto-optic medium 611 will be transmitted to subsequent components in a reverse mapping manner. For example, suppose the front focal plane of the convex lens L1 is located at coordinate x=a, and the rear focal plane of the convex lens L2 is separated from it by an equivalent focal length in the optical axis direction. When the light beam exits from the front focal plane of the convex lens L1 with a lateral coordinate of y and a propagation angle of θ, after being refracted by the convex lens L1 and the convex lens L2, the light beam will exit from the rear focal plane of the convex lens L2 with a lateral coordinate of -y and a propagation angle of -θ.

[0093] In another embodiment, the fixed installation angle θ of the first polarizing prism 71 inside the three-mirror rotating optical tube 7 is adjusted. P And the fixed installation angle -θ of the second polarizing prism 72 inside the three-mirror rotating optical tube 7. P This is such that when the incident beam is incident along the optical axis to the center of the mirror of the first polarizing prism 71, the incident beam will be refracted to the center of the total reflection mirror 73 inside the three-mirror rotating optical tube 7. After being reflected by the total reflection mirror 73, the beam is incident to the center of the lens of the second polarizing prism 72. After being refracted by the center of the mirror of the second polarizing prism 72, the beam exits horizontally along the optical axis.

[0094] In another embodiment, the three-mirror rotating optical tube 7 is driven to rotate by an external high-speed rotating transmission device 74. In specific applications, the high-speed rotating transmission device 74 is controlled by a high-speed servo motor, which is connected to a servo driver, and the servo driver is controlled by a signal terminal controller 12.

[0095] In another embodiment, the monitoring camera module 8 is connected to the signal terminal controller 12. The monitoring camera module 8 can transmit the acquired hole-making image to the host computer control system 11 via the signal terminal controller 12. In specific applications, the signal terminal controller 12 compares the image with the target conical hole model preset by the host computer control system 11 to obtain error information on the hole diameter, cone shape, and hole depth. Based on this error, it generates a feedback adjustment command. After receiving the command, the signal terminal controller 12 adjusts the parameters of the adjustment pulse laser 1, the control signals of the first radio frequency signal generator 13 and the second radio frequency signal generator 14, and the Z-axis focusing module 10 in real time to correct the shape of the hole, so that the processing result gradually approaches the preset target, thereby realizing closed-loop adaptive adjustment.

[0096] like Figure 10 As shown, according to another aspect of the present invention, a method for fabricating pores based on the above-described acousto-optic effect-based precision micro / nano pore fabrication device is provided, comprising the following steps:

[0097] S10. Reset the precision micro-nano hole fabrication device based on acousto-optic effect, turn on the monitoring camera module 8 and its light source, and adjust the parameters of the pulsed laser 1.

[0098] S20. Fix the sample to be processed on the three-axis machining platform 15, and send a control signal to the signal terminal controller 12 through the host computer control system 11 to move the three-axis machining platform 15 to the camera center of the monitoring camera module 8.

[0099] S30. Load the preset target conical hole model into the host computer control system 11 and send control commands to the signal terminal controller 12. After receiving the commands, the signal terminal controller 12 sends control signals to the first radio frequency signal generator 13, the second radio frequency signal generator 14, the high-speed rotation drive device and the Z-axis focusing module 10.

[0100] S40, the acousto-optic off-axis adjustment module 5 receives the control signal and adjusts the lateral translation offset of the beam relative to the optical axis; the acousto-optic angle deflection module 6 receives the control signal and adjusts the angle of the beam incident on the three-mirror rotating optical tube 7; the Z-axis focusing module 10 receives the control signal and adjusts the focal depth.

[0101] S50, the high-speed rotation drive device receives the control signal and drives the three-mirror rotating optical tube 7 to rotate at high speed. The emitted light beam is reflected by the dichroic mirror 9 onto the workpiece at the three-axis machining platform 15 and is then rotated around the optical axis at high speed.

[0102] S60, the monitoring camera module 8 captures the processing scene and uploads it to the host computer control system 11. It compares the scene with the preset target conical hole model to obtain error information on hole diameter, cone shape and hole depth. Based on the error, it generates a feedback command and sends it to the terminal signal controller to form a closed loop adjustment.

[0103] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A precise micro / nano aperture fabrication device based on acousto-optic effect, characterized in that, include: The light source system is used to output the required laser beam; An acousto-optic off-axis adjustment module is disposed on the output optical axis of the light source system; An acousto-optic angle deflection module is disposed on the output optical axis of the acousto-optic off-axis adjustment module. The three-mirror rotating optical tube is disposed on the output optical axis of the acousto-optic angle deflection module; A dichroic mirror is disposed on the output optical axis of the three-mirror rotating optical tube; A monitoring camera module and a three-axis machining platform are provided, wherein the monitoring camera module is positioned above the dichroic mirror and the three-axis machining platform is positioned below the dichroic mirror; A first radio frequency signal generator and a second radio frequency signal generator, wherein the first radio frequency signal generator is electrically connected to the acousto-optic off-axis adjustment module, and the second radio frequency signal generator is electrically connected to the acousto-optic angle deflection module; The host computer control system is electrically connected to the monitoring camera module, the first radio frequency signal generator, and the second radio frequency signal generator. The light source system includes a pulsed laser, a beam expander, a half-wave plate, and a mirror module. The beam expander is disposed on the output optical axis of the pulsed laser. The half-wave plate is arranged on the side of the beam expander away from the pulsed laser, and its optical center is located on the output optical axis of the beam expander. The mirror module is disposed on the output optical axis of the half-wave plate. The reflector module includes a first reflector and a second reflector. The center of the mirror surface of the first reflector is located on the output optical axis of the half-wave plate, and the normal of the mirror surface of the first reflector is arranged at a 45° angle to the output optical axis of the half-wave plate. The center of the second reflector is located on the output optical axis of the first reflector, and the normal of the second reflector is installed at an adjustable angle θ with the output optical axis of the first reflector, so that the output beam from the second reflector can be emitted at a predetermined output angle θ. B1 Reached the first expected position; The acousto-optic off-axis adjustment module includes a first acousto-optic action module, a first aperture, an image-side telecentric correction module, and a leveling mechanism. The first acousto-optic action module includes a first acousto-optic medium, a first ultrasonic transducer, a first sound-absorbing material, and a first electrode. The first acousto-optic module is positioned at the first intended location, enabling the emitted light beam from the second reflector to be incident on the central action area of ​​the first acousto-optic medium, so as to receive the light beam from the second reflector at an angle θ. B1 The emitted light beam has a first ultrasonic transducer attached to one end of the first acousto-optic medium, and the other end of the first acousto-optic medium is attached to the first sound-absorbing material. A first electrode is attached to the surface of the first ultrasonic transducer and connected to the external drive port of the first acousto-optic module to receive radio frequency signals, causing the light beam to generate +1st, 0th, and other higher orders (±n) diffracted light after passing through the first acousto-optic module. The central action area of ​​the first acousto-optic medium is located at the entrance pupil of the image-side telecentric correction module. A first aperture is placed in the emitted light path of the first acousto-optic module, located after the first acousto-optic medium. The position and size of the aperture of the first aperture are limited to allow only the required +1st order diffracted light to pass through. It blocks 0th-order diffraction light and other useless diffraction-order secondary light; the image-side telecentric correction module is located on the output optical axis of the first acousto-optic module and behind the first aperture, with its entrance pupil aligned with the aperture of the first aperture, so that the +1st-order diffraction angle deflection information generated by the first acousto-optic module is converted into a lateral translation offset relative to the optical axis; the first acousto-optic module, the first aperture, and the image-side telecentric correction module are sequentially aligned with the optical path, and after their relative positions are fixed, they are encapsulated in the same metal housing with an entrance window and an exit window; the leveling mechanism is installed at the bottom of the metal housing and is used to finely adjust the tilt angle of the output beam of the image-side telecentric correction module so that the output beam of the image-side telecentric correction module can be at a predetermined exit angle θ. B2 Reached the second expected position.

2. The precise micro / nano aperture fabrication device based on acousto-optic effect according to claim 1, characterized in that, The acousto-optic angle deflection module includes a second acousto-optic action module, a 4f angle relay module, and a second aperture. The second acousto-optic action module includes a second acousto-optic medium, a second ultrasonic transducer, a second sound-absorbing material, and a second electrode. The second acousto-optic module is positioned at the second intended location, enabling the emitted light beam from the image-side telecentric correction module to be incident on the central action area of ​​the second acousto-optic medium, so as to receive the light beam from the image-side telecentric correction module at an angle θ. B2 The emitted light beam has a second ultrasonic transducer tightly disposed at one end of the second acousto-optic medium, and the other end of the second acousto-optic medium is attached to the second sound-absorbing material. A second electrode is attached to the surface of the second ultrasonic transducer and connected to the external drive port of the second acousto-optic module to receive radio frequency signals, causing the light beam to generate +1, 0, and other higher orders ±n-order diffraction light after passing through the second acousto-optic module. The central action area of ​​the second acousto-optic medium is located at the entrance pupil of the 4f-angle relay module. The 4f-angle relay module includes a convex lens L1 and a convex lens L2, both of which are identical biconvex lenses with a focal length of f. The center of the mirror surface of the convex lens L1 is located on the emitted horizontal optical axis of the second acousto-optic module. The distance between the central active area of ​​the second acousto-optic medium and the central active area of ​​the second acousto-optic medium is one focal length f, so that the central active area of ​​the second acousto-optic medium is located at the entrance pupil of the 4f-angle relay module. The center of the mirror surface of the convex lens L2 is set on the horizontal optical axis of the convex lens L1, and the distance between the convex lens L1 and the convex lens L2 is two focal lengths 2f. The second aperture is set at the center between the optical axes of the convex lens L1's exit direction and the convex lens L2's incident direction. The position and size of the aperture of the second aperture are limited to allow only the required +1st order diffraction light to pass through, and block the 0th order diffraction light and other useless diffraction order light. The second acousto-optic active module, the 4f-angle relay module and the second aperture are aligned with the optical path in sequence, and after fixing their relative positions, they are encapsulated in the same metal housing with an entrance window and an exit window.

3. The precise micro / nano aperture fabrication device based on acousto-optic effect according to claim 2, characterized in that, The precise micro / nano aperture fabrication device based on acousto-optic effect further includes a signal terminal controller, which is electrically connected to the host computer control system. The first radio frequency signal generator includes a first radio frequency generator and a first radio frequency amplifier. The first radio frequency generator is electrically connected to the first radio frequency amplifier, the first radio frequency amplifier is electrically connected to the first electrode, and the first radio frequency generator is electrically connected to the signal terminal controller. The second radio frequency generator is electrically connected to the second radio frequency amplifier, the second radio frequency amplifier is connected to the second electrode, and the second radio frequency generator is electrically connected to the signal terminal controller.

4. The precise micro / nano aperture fabrication device based on acousto-optic effect according to claim 3, characterized in that, The three-mirror rotating optical tube includes a first polarizing prism, a second polarizing prism, a total reflection mirror, and a high-speed rotation drive device. The mirror centers of the first and second polarizing prisms are located on the output optical axis of the acousto-optic angle deflection module. The first polarizing prism rotates at a predetermined angle θ. P The second polarizing prism is fixedly installed inside the three-mirror rotating optical tube, and is positioned at a predetermined angle -θ. P The total reflection mirror is fixedly installed on the output optical axis of the first polarizing prism in an axially symmetrical manner. The total reflection mirror is located between the first polarizing prism and the second polarizing prism and is fixedly installed at the bottom of the three-mirror rotating optical tube. The high-speed rotation drive device is installed on the outside of the three-mirror rotating optical tube.

5. The precise micro / nano aperture fabrication device based on acousto-optic effect according to claim 4, characterized in that, The precise micro / nano hole-making device based on acousto-optic effect also includes a Z-axis focusing module, which is located between the dichroic mirror and the triaxial processing platform and is situated on the outgoing optical axis of the dichroic mirror.

6. The precise micro / nano aperture fabrication device based on acousto-optic effect according to claim 5, characterized in that, The three-axis machining platform includes a fixture and a three-axis motion module. The fixture is mounted on the three-axis motion module and is used to clamp and position the sample to be processed. The three-axis motion module is used to drive the sample to be processed to move in at least one of the horizontal transverse, horizontal longitudinal and vertical directions.

7. A method for fabricating pores using a precise micro / nano pore fabrication device based on the acousto-optic effect as described in claim 6, characterized in that, Includes the following steps: S10. Reset the acousto-optic precision micro / nano hole fabrication device, turn on the monitoring camera module and its light source, and adjust the pulsed laser parameters. S20. Fix the sample to be processed on the three-axis machining platform, and send a control signal to the signal terminal controller through the host computer control system to move the three-axis machining platform to the camera center of the monitoring camera module. S30. Load the preset target conical hole model into the host computer control system and send control commands to the signal terminal controller. After receiving the commands, the signal terminal controller sends control signals to the first radio frequency signal generator, the second radio frequency signal generator, the high-speed rotation drive device and the Z-axis focusing module. S40, the acousto-optic off-axis adjustment module receives control signals and adjusts the lateral translation offset of the beam relative to the optical axis; the acousto-optic angle deflection module receives control signals and adjusts the angle of the beam incident on the rotating optical tube of the three mirrors; the Z-axis focusing module receives control signals and adjusts the depth of focus. S50: The high-speed rotation drive device receives the control signal and drives the three-mirror rotating optical tube to rotate at high speed. The emitted light beam is reflected by the dichroic mirror onto the workpiece at the three-axis machining platform and is then rotated around the optical axis at high speed. The S60 monitoring camera module captures the processing footage and uploads it to the host computer control system. It compares the footage with the preset target conical hole model to obtain error information on the hole diameter, cone shape, and hole depth. Based on the error information, it generates feedback commands and sends them to the terminal signal controller to form a closed-loop regulation.

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