An ultra-thin prepreg single laser drilling system

Abstract

The application relates to the technical field of laser processing, and particularly discloses a single-shot laser pore forming system for ultrathin prepreg, which aims to solve the contradiction between precision, thermal damage and efficiency in laser processing of the ultrathin prepreg; the system is cooperated by an ultrashort pulse laser source, precise beam shaping and transmission, material processing and positioning, real-time monitoring and feedback, and intelligent control and optimization modules, so as to finely regulate and control the interaction between the laser and the material. In a single or equivalent single laser event, the ultrathin prepreg is processed into a microstructure with high precision and low damage, defects such as a thermal affected zone, carbonization and delamination are effectively reduced, and the processing quality and efficiency are improved.

Description

Technical Field

[0001] This invention belongs to the field of laser processing technology, specifically relating to a single-shot laser hole-forming system for ultrathin prepreg sheets. Background Technology

[0002] In modern industrial manufacturing, precision materials processing technology, especially the refined processing of high-performance composite materials, is key to driving the development of many high-tech industries. With the increasing demands for miniaturization, lightweighting, and integration of components in fields such as electronics, aerospace, and new energy, unprecedented challenges have been placed on the processing precision and efficiency of ultra-thin materials. Laser processing technology, with its advantages of non-contact operation, high energy density, and high precision, has become an indispensable advanced method in precision manufacturing, demonstrating enormous potential in processes such as cutting, drilling, and welding of various materials.

[0003] Ultrathin prepregs, as a core medium in printed circuit boards (PCBs) and packaging substrates, place extreme demands on the quality of hole formation due to their high performance and reliability. Laser drilling technology, with its unique advantages, is gradually replacing traditional mechanical drilling and becoming the preferred solution for precision hole formation on ultrathin prepregs, aiming to achieve micro-aperture, high-density arrangement, and excellent hole wall quality.

[0004] Current technologies for laser drilling of ultrathin prepregs still face many unresolved problems. Traditional mechanical drilling methods, due to their contact processing, are prone to material damage, have limited precision, and are inefficient, making them unsuitable for processing ultrathin materials. While multi-shot laser drilling improves efficiency, the cumulative energy effect can lead to an excessively large heat-affected zone (HAZ), severe ablation at the hole edges, irregular hole shapes, and can cause delamination or structural damage to ultrathin materials. Existing single-shot laser drilling technology, although improved in some aspects, still has many limitations. For example, it is difficult to precisely control the energy distribution of a single pulse to obtain ideal hole shape and hole wall quality, and it is prone to problems such as burrs, taper, or residue adhesion. Furthermore, for ultrathin prepregs of different thicknesses and materials, the system lacks versatility and process stability, making it difficult to ensure both production efficiency and processing precision and quality. Therefore, how to achieve efficient, high-precision, and high-quality single-shot laser drilling of ultrathin prepregs has become a critical technical challenge that urgently needs to be overcome in this field. Summary of the Invention

[0005] This invention provides a single-shot laser drilling system for ultrathin prepregs, aiming to overcome the technical contradictions between precision, thermal damage, and efficiency faced by existing laser processing technologies when handling ultrathin prepregs. Existing technologies typically employ multiple pulses or a single high-energy pulse for processing. However, multiple pulses are inefficient, while a single high-energy pulse easily causes significant heat-affected zones, carbonization, delamination, and irregular hole shapes in ultrathin and heat-sensitive prepreg materials. These problems severely limit the application of ultrathin prepregs in the manufacturing of high-end electronic products, particularly in the production of printed circuit boards and flexible electronic devices requiring extremely high density and reliability. This invention integrates advanced ultrashort pulse laser technology, precision beam shaping technology, and a real-time feedback control mechanism to achieve precise control of the laser-material interaction process. This allows for high-precision, low-damage microstructure processing, including hole drilling and slit cutting, to be completed in a single or equivalent single laser event.

[0006] According to one aspect of the present invention, a single-shot laser drilling system for ultrathin prepregs is provided, comprising: an ultrashort pulse laser source module, a beam shaping and transmission module, a material processing and positioning module, a real-time monitoring and feedback module, and an intelligent control and optimization module. The modules of the system work collaboratively to achieve efficient and precise microstructure processing of ultrathin prepregs.

[0007] Ultrashort pulse laser source modules are used to generate laser pulses with specific parameters. These pulses have ultrashort pulse widths, for example, on the order of femtoseconds or picoseconds. The modules can generate laser outputs with high peak power and low single-pulse energy. The center wavelength of the laser pulses generated by the module can be in the ultraviolet, visible, or infrared bands, for example, 355 nm, 532 nm, or 1064 nm. The modules have adjustable pulse repetition frequencies, for example, in the range of kilohertz to megahertz. They also have adjustable single-pulse energy output capabilities, for example, in the range of microjoules to millijoules. The modules ensure good beam quality and stability of the output laser beam. This laser source module is key to achieving "cold" ablation of materials; through extremely short pulse durations, the laser energy ablates the target area before heat diffuses to the surrounding material, thus significantly reducing the heat-affected zone.

[0008] The beam shaping and transmission module is optically connected to the ultrashort pulse laser source module. It precisely shapes the received laser pulses spatially and temporally, and transmits the shaped laser beam to the surface of the ultrathin prepreg. The beam shaping and transmission module includes: a beam expander, a spatial light modulator, a diffractive optical element, an aperture, a focusing optical system, and a scanning galvanometer. The beam expander adjusts the diameter of the laser beam to match the size requirements of subsequent optical elements, ensuring beam uniformity upon entering the shaping system. The spatial light modulator or diffractive optical element allows for arbitrary control of the spatial intensity distribution of the laser beam to produce the desired processing spot shape, such as a flat-top spot, a ring spot, a multi-point array spot, or a linear spot. The aperture precisely defines the physical size and shape of the laser beam. The focusing optical system employs a high numerical aperture telecentric f-θ scanning lens system to ensure a uniform focused spot size and shape within the working plane and provides high-precision focusing depth control. Scanning galvanometers are used to achieve high-speed and high-precision scanning and positioning of laser beams on the surface of ultra-thin prepregs to complete complex pattern processing paths.

[0009] Furthermore, the beam shaping and transmission module also includes a time-pulse shaping unit. This unit is used to regulate the temporal characteristics of the laser pulse. The time-pulse shaping unit can consist of a pulse stretcher, pulse compressor, electro-optic modulator, or acousto-optic modulator. It can decompose a seemingly single laser event into a series of closely connected sub-pulses, forming pulse clusters or a pre-pulse-main-pulse-post-pulse sequence. By precisely controlling the interval, energy, and duration of these sub-pulses, the system can achieve layer-by-layer material removal, preheating, main ablation, and post-processing within the effective single laser irradiation time, thereby optimizing the ablation effect and minimizing thermal damage.

[0010] The material handling and positioning module is used for precise fixation, positioning, and motion control of the ultrathin prepreg. This module includes a high-precision vacuum chuck or electrostatic chuck, a high-resolution motion platform, a dust removal system, and a gas environment control unit. The high-precision vacuum chuck or electrostatic chuck ensures the ultrathin prepreg maintains extremely high flatness and stability during processing, eliminating the impact of warping and vibration on processing accuracy. The high-resolution motion platform includes an XYZ three-axis linear motion platform equipped with a high-precision linear encoder, achieving nanometer-level positioning accuracy and high-speed movement capability of the ultrathin prepreg in three-dimensional space. The Z-axis motion platform is used to precisely adjust the relative position of the laser focusing plane and the surface of the ultrathin prepreg. The dust removal system integrates efficient vacuum suction and filtration devices to remove particles and fumes generated during laser ablation in real time, preventing contamination of optical components or secondary pollution of the processing area. The gas environment control unit can deliver inert gases such as nitrogen, argon, or reactive gases such as oxygen to the processing area to control the chemical environment during laser ablation, thereby affecting the ablation rate, the size of the heat-affected zone, and the morphology of the hole edge or cutting edge.

[0011] The real-time monitoring and feedback module is used to monitor the interaction between the laser and the material, as well as the processing results, in real time during laser processing. This module includes a high-speed vision camera, a thermal imager, a spectrometer, and an optical coherence tomography (OCT) scanner or confocal microscope. The high-speed vision camera, including visible light or infrared cameras, is used to observe the plasma plume generated during laser ablation, the dynamics of material ejection, and the instantaneous morphology of the processed surface. The thermal imager is used to monitor the local temperature distribution in the processed area in real time to assess the size of the heat-affected zone. The spectrometer is used to analyze the emission spectrum of the plasma plume to infer changes in material composition and ablation efficiency. The OCT scanner or confocal microscope is used to acquire three-dimensional depth information and precise geometric dimensions of the microstructure during or immediately after processing, such as the depth and diameter of holes and the width and depth of cuts. The real-time monitoring and feedback module preprocesses the acquired data, including noise suppression, feature extraction, and time synchronization, and then transmits the processed data to the intelligent control and optimization module with extremely low latency.

[0012] The intelligent control and optimization module is the core of the entire system. It receives data from the real-time monitoring and feedback module and dynamically adjusts and optimizes the parameters of the ultrashort pulse laser source module, beam shaping and transmission module, and material handling and positioning module according to preset processing targets. The intelligent control and optimization module includes: a high-performance industrial computer, an embedded real-time processor such as a field-programmable gate array (FPGA) or digital signal processor (DSP), a process parameter database, and a machine learning or adaptive control engine. The high-performance industrial computer and embedded real-time processor provide powerful computing capabilities and real-time control response speed. The process parameter database stores the optimal laser parameter set for different types of ultrathin prepreg materials and different microstructure processing targets, including pulse energy, pulse width, repetition frequency, spatial spot shape, and temporal pulse sequence.

[0013] The machine learning or adaptive control engine is the core of the intelligent control and optimization module. It receives real-time monitoring data, compares it with target processing parameters, and predicts the processing result deviation under the current parameter settings using a pre-trained machine learning model, such as a neural network or deep learning model. Based on the prediction results, the machine learning or adaptive control engine implements a closed-loop control algorithm to dynamically adjust parameters such as the output power, pulse width, and pulse repetition frequency of the ultrashort pulse laser source module, the spot shape and scanning speed of the beam shaping and transmission module, and the ambient gas flow rate of the material handling and positioning module. The goal of the machine learning or adaptive control engine is to achieve adaptive optimization of the processing process, thereby minimizing thermal damage, ensuring geometric accuracy, improving processing efficiency, and enhancing the robustness and reliability of the system under different materials and processing tasks. Furthermore, for laser cutting tasks, the intelligent control and optimization module also includes advanced trajectory planning algorithms to generate smooth, high-speed, and high-precision cutting paths, taking into account the kerf width and material removal characteristics. The intelligent control and optimization module also provides an intuitive user interface for operators to set processing tasks, monitor processing status, and evaluate processing quality.

[0014] The workflow of the entire single-shot laser drilling system for ultrathin prepreg sheets is as follows: The operator selects the type of ultrathin prepreg material to be processed through the user interface and inputs the desired microstructure processing targets, such as hole diameter, cutting line width, and depth. The intelligent control and optimization module retrieves and loads the initial processing parameters from the process parameter database. The ultrathin prepreg sheet is precisely fixed on the high-precision chuck of the material handling and positioning module and moved to the processing starting position by a high-resolution motion platform. The ultrashort pulse laser source module generates laser pulses with specific parameters according to the instructions of the intelligent control and optimization module. The laser pulses enter the beam shaping and transmission module, undergo precise spatial and temporal shaping to form a spot with the desired shape and temporal characteristics, and are precisely guided to the surface of the ultrathin prepreg sheet by a scanning galvanometer. The laser beam interacts with the material, completing one or equivalent single-shot formation of the microstructure. The real-time monitoring and feedback module captures real-time data on plasma plume, material ablation products, local temperature, and the geometry of the formed microstructure at the moment of laser action and afterward. This data is rapidly transmitted to the intelligent control and optimization module for analysis. Based on the discrepancy between real-time data and preset targets, the intelligent control and optimization module uses machine learning or an adaptive control engine to calculate the optimal parameter adjustment scheme in a very short time. It then immediately sends instructions to the ultrashort pulse laser source module, beam shaping and transmission module, and material processing and positioning module to dynamically correct laser parameters, beam characteristics, and the material processing environment. This closed-loop feedback and optimization process continues until all microstructure processing tasks are completed, ensuring that each laser action achieves high precision, low damage, and high efficiency.

[0015] Compared with the prior art, the advantages and positive effects of the present invention are as follows:

[0016] This invention introduces an ultrashort pulse laser source, which achieves "cold" ablation of ultrathin prepregs with a pulse width of femtosecond or picosecond. This greatly reduces defects commonly found in traditional laser processing, such as heat-affected zones, carbonization, delamination, and burrs, and significantly improves processing quality and material integrity.

[0017] This invention integrates an advanced beam shaping and transmission module. Through a spatial light modulator, diffractive optical elements, and a time pulse shaping unit, it achieves precise control over the shape of the laser spot and the pulse sequence. This allows a single laser event to form an optimal energy deposition profile based on material properties and processing requirements, thereby completing the precise shaping of complex microstructures in one or an equivalent single action, ensuring the roundness of the aperture and the cleanliness of the cutting edges.

[0018] This invention deploys a real-time monitoring and feedback module, which uses a variety of sensors such as high-speed vision cameras, thermal imagers, spectrometers, and optical coherence tomography scanners to comprehensively monitor the laser ablation process and results in situ, providing rich and timely process data.

[0019] This invention constructs an intelligent control and optimization module. Its core machine learning or adaptive control engine can dynamically adjust laser parameters, beam characteristics, and material processing environment based on real-time feedback data, achieving adaptive optimization of the processing. This closed-loop control mechanism effectively compensates for fluctuations in material and environmental factors, ensuring processing accuracy and stability, and significantly reducing manual intervention and trial-and-error costs.

[0020] This invention, through a material processing and positioning module consisting of a high-precision vacuum chuck, a multi-axis motion platform, and a gas environment control unit, ensures the extreme flatness and precise micron-level positioning of the ultra-thin prepreg during processing, providing a stable and reliable physical basis for the precise application of lasers.

[0021] This invention improves processing efficiency while ensuring extremely high processing quality, enabling ultra-thin prepregs to be more widely used in advanced electronic manufacturing fields with stringent requirements for precision and reliability, such as high-density interconnect printed circuit boards, flexible electronics, and chip packaging. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall technical solution architecture of the present invention;

[0023] Figure 2 This is a schematic diagram of the real-time monitoring and feedback module architecture of the present invention. Detailed Implementation

[0024] This embodiment provides a single-shot laser drilling system for ultrathin prepreg sheets. This system aims to address the comprehensive challenges faced by existing laser technologies in the processing of ultrathin prepreg sheets, including insufficient precision, significant thermal damage, and low processing efficiency. By integrating advanced ultrashort pulse laser technology, precision beam shaping and transmission technology, and a real-time closed-loop feedback control mechanism, this system aims to achieve high-precision, low-thermal-damage microstructure processing of ultrathin prepreg materials, covering various application scenarios such as hole forming and fine slit cutting.

[0025] Please refer to Figure 1 and Figure 2The single-shot laser drilling system for ultrathin prepreg sheets of this invention mainly consists of the following five core functional modules: an ultrashort pulse laser source module, a beam shaping and transmission module, a material processing and positioning module, a real-time monitoring and feedback module, and an intelligent control and optimization module. These modules work closely together through carefully designed functional interfaces and data interaction protocols to achieve comprehensive and precise microstructure processing control of ultrathin prepreg materials.

[0026] The ultrashort pulse laser source module is responsible for generating laser pulses with specific physical parameters. The laser pulses output by this module have ultrashort pulse widths, typically in the femtosecond or picosecond range. This extremely short pulse duration is the key physical basis for achieving "cold" ablation of materials. The mechanism involves the deposition of laser energy into the target material region within a very short time, causing the material to ablate and vaporize before the energy diffuses to the surrounding area through thermal conduction, thus significantly suppressing the formation of the heat-affected zone. The ultrashort pulse laser source module can generate high peak power while maintaining low single-pulse energy laser output characteristics, which further enhances the "cold" ablation effect. The center wavelength of the laser pulses generated by the module is selective, covering the ultraviolet band (e.g., 355 nm), the visible light band (e.g., 532 nm), or the infrared band (e.g., 1064 nm). The wavelength selection depends on the absorption characteristics of the ultrathin prepreg material to be processed for different laser bands, in order to optimize energy absorption efficiency and minimize material damage. The ultrashort pulse laser source module features an adjustable pulse repetition frequency, typically ranging from kilohertz to megahertz. A high repetition frequency improves processing efficiency, while precise control of single-pulse energy avoids accumulated heat effects. The module also offers adjustable single-pulse energy output, typically ranging from microjoules to millijoules, to accommodate different materials and processing depths. Through a built-in laser cavity stability control system and beam quality monitoring system, the module ensures excellent beam quality, such as a low M² factor and long-term output stability, including power fluctuations of less than one percent and pointing stability of less than microradians. The ultrashort pulse laser source module's controller communicates with the intelligent control and optimization module via a digital interface, receiving commands regarding pulse width, repetition frequency, single-pulse energy, and wavelength selection, and providing real-time feedback on the laser output status. The laser source integrates a high-precision temperature sensor and an active cooling system to maintain a stable operating temperature for the laser gain medium and optical components, ensuring the accuracy and repeatability of laser parameter output.

[0027] The beam shaping and transmission module is physically connected and optically coupled to the ultrashort pulse laser source module through a precise optical path system. Its function is to precisely shape the received laser pulses in both spatial and temporal dimensions, and then efficiently and accurately transmit the optimized laser beam to the processing surface of the ultrathin prepreg material. This module is a key execution unit for achieving the precision forming of complex microstructures, determining the instantaneous geometry, energy distribution, and timing of the laser's impact on the material. The components of the beam shaping and transmission module include: a beam expander, a spatial light modulator, diffractive optical elements, an aperture, a focusing optical system, and a scanning galvanometer.

[0028] A beam expander is used to adjust the cross-sectional diameter of a laser beam. Its main function is to match the size requirements of subsequent optical components, especially spatial light modulators and focusing optics, thereby ensuring a uniform energy density distribution of the laser beam as it enters the shaping system, avoiding edge effects and distortion. Beam expanders typically employ Galilean or Keplerian structures, and their magnification can be precisely configured according to the original and target diameters of the laser beam, ensuring effective control of the beam divergence angle. The placement of the beam expander in the optical path is rigorously calculated to maintain the axial stability of the entire optical path.

[0029] Spatial light modulators, or diffractive optical elements, are core components for achieving arbitrary control of the spatial intensity distribution of a laser beam. Spatial light modulators typically employ liquid crystal arrays or microelectromechanical systems (MEMS) mirror arrays. By applying an electric field or physical deformation, they locally modulate the phase, amplitude, or polarization state of the incident laser beam, thereby reconstructing the beam's intensity distribution and generating the desired processing spot shape. For example, a Gaussian beam can be reshaped into a flat-topped spot with uniform energy distribution using precise phase modulation algorithms. This spot can significantly improve the perpendicularity of the hole wall and reduce the heat-affected zone in hole forming. Furthermore, the system can generate annular spots for the "knife-cutting" effect in laser cutting or drilling, multi-point array spots for parallel processing to improve efficiency, or linear spots for slit cutting. Diffractive optical elements, on the other hand, diffract light waves through micro / nano structures to generate a pre-defined complex light field distribution. Their advantages include high stability and low energy loss, making them suitable for large-scale production. Both the spatial light modulator and the diffractive optical element communicate with the intelligent control and optimization module to receive instructions on the shape of the target light spot and adjust their modulation parameters in real time.

[0030] An aperture stop is used to precisely define the physical size and shape of a laser beam. It removes stray light or inhomogeneities from the edges of the laser beam through physical blocking, ensuring that the laser beam entering the focusing optics system has a highly clear and stable spot profile, which in turn affects the geometric accuracy of the final processed microstructure. The aperture of the aperture stop is typically adjustable, or achieved through a series of switchable fixed apertures, to adapt to the precise spot size requirements of different processing tasks.

[0031] The focusing optics system employs a high numerical aperture (NA) telecentric f-θ scanning lens system. The telecentric optical design ensures a constant incident angle of the laser beam within the scanning working plane, resulting in a uniform focused spot size and shape across the entire processing area and avoiding distortions caused by conventional lenses in edge regions. The high numerical aperture (NA) ensures the laser beam can be focused to an extremely small size, enabling high energy density and high-resolution processing. The f-θ scanning lens system linearly converts the angular displacement of the scanning galvanometer into linear displacement within the working plane, simplifying scanning path control. The system also features high-precision focusing depth control, using a Z-axis motion platform to drive axial movement of the focusing optics system, achieving micron- or even sub-micron-level precise adjustments to the laser focal point position to accommodate materials of varying thicknesses or to perform layer-by-layer processing of multi-layered materials.

[0032] A scanning galvanometer is used to achieve high-speed and high-precision scanning and positioning of a laser beam on the surface of an ultra-thin prepreg. The scanning galvanometer consists of two mirrors, corresponding to the X and Y axes respectively, driven by independent servo motors to achieve rapid deflection of the laser beam in a two-dimensional plane. Its core technologies lie in a high-performance servo control system and a high-precision angle encoder, ensuring that the positioning accuracy of the laser beam reaches the micrometer level, and that the repeatability and trajectory tracking accuracy meet the requirements of high-end micromachining. The motion commands for the scanning galvanometer come from an intelligent control and optimization module, used to complete complex graphic processing paths, including straight-line scanning, curve scanning, and the generation and execution of trajectories for arbitrarily complex patterns. Scanning speed, acceleration, and the galvanometer's response time are key parameters affecting processing efficiency and accuracy.

[0033] Furthermore, the beam shaping and transmission module also includes a time-pulse shaping unit. This unit is used for fine-tuning the temporal characteristics of the laser pulse. The time-pulse shaping unit can consist of a pulse stretcher, a pulse compressor, an electro-optic modulator, or an acousto-optic modulator. Its core function is to decompose and reconstruct a seemingly single laser event into a series of closely connected sub-pulse sequences, forming pulse clusters or a pre-pulse-main-pulse-post-pulse sequence. By precisely controlling the interval time between these sub-pulses, the energy distribution of each sub-pulse, and its duration, the system can achieve multi-stage processes such as layer-by-layer material removal, preheating, main ablation, and post-processing within an effective single laser attack time. For example, a weak pre-pulse can be used to clean the material surface or preheat the target area, reducing the ablation threshold of the main pulse; the main pulse is responsible for the main material removal; while one or more post-pulses can be used to remove ablation products, optimize the morphology of hole walls or cutting edges, thereby minimizing thermal damage and improving processing quality. Pulse stretchers and compressors typically employ grating pairs or prism pairs, using dispersion effects to change the pulse width. Electro-optic modulators and acousto-optic modulators utilize the electro-optic effect or acousto-optic effect to achieve rapid switching and intensity modulation of light pulses, thereby generating complex pulse sequences. The control parameters of the time pulse shaping unit, such as the number of sub-pulses, energy ratio, and time delay, interact in real time with the digital interface of the intelligent control and optimization module to adapt to different material properties and processing requirements.

[0034] The material handling and positioning module is used for the precise fixation, positioning, and motion control of ultra-thin prepreg material in three-dimensional space. This module is the physical basis for ensuring processing accuracy and repeatability. The material handling and positioning module includes: a high-precision vacuum chuck or electrostatic chuck, a high-resolution motion platform, a dust removal system, and a gas environment control unit.

[0035] High-precision vacuum chucks or electrostatic chucks are used to ensure the extremely high flatness and stability of ultrathin prepregs throughout the entire processing. For flexible materials like ultrathin prepregs, warping or minor vibrations are easily caused by their own weight, airflow disturbances, or thermal stress, all of which severely affect the precision of laser processing. Vacuum chucks eliminate warping by creating negative pressure on their surface, tightly adhering the material to a flat substrate. The chuck surface is typically designed with micron-sized, uniformly distributed vacuum holes and is made of highly flat ceramic or metal materials. Electrostatic chucks utilize the principle of electrostatic adsorption, generating electrostatic force between the chuck and the material by applying high voltage, achieving contactless material fixation, and are particularly suitable for applications requiring extremely precise adsorption traces. Chuck systems are typically equipped with high-precision pressure or voltage sensors to monitor the adsorption state in real time and adjust the power of the vacuum pump or the output of the high-voltage power supply via feedback loops to ensure the stability and uniformity of the adsorption force.

[0036] The high-resolution motion platform includes a three-axis XYZ linear motion platform equipped with a high-precision linear encoder. The two-axis XY linear motion platform enables high-speed and nanometer-level positioning accuracy movement of the ultrathin prepreg in a two-dimensional plane, carrying the material and collaboratively completing complex pattern processing paths according to the instructions of the scanning galvanometer. These platforms are typically driven by linear motors, offering advantages such as high response speed, high acceleration, and wear-free operation. The Z-axis motion platform precisely adjusts the relative position of the laser's focusing plane to the surface of the ultrathin prepreg material. By combining surface height information provided by a real-time monitoring module, the Z-axis platform can dynamically compensate, ensuring that the laser focus always falls precisely on the material surface or at a preset depth, thus maintaining focus consistency during processing. High-precision linear encoders, such as grating rulers or laser interferometers, provide nanometer-level displacement feedback, ensuring the positioning accuracy and repeatability of the motion platform, which is crucial for achieving micrometer-level or even sub-micrometer-level processing accuracy. The motion platform's controller and intelligent control and optimization module receive commands and provide position feedback via a high-speed digital communication bus, such as EtherCAT or Profinet.

[0037] The dust removal system integrates highly efficient vacuum suction and filtration devices to remove particles and fumes generated during laser ablation in real time. If these particles and fumes are not removed promptly, they can contaminate optical components, leading to decreased laser energy transmission efficiency, deteriorated spot quality, and even damage to the components. Furthermore, these products may undergo secondary deposition in the processing area, affecting processing quality, such as causing rough hole walls or edge burrs. The dust removal system uses a powerful vacuum pump to create a negative pressure airflow above or to the side of the processing area, rapidly extracting the ablation products. The gas is then purified through multi-stage high-efficiency filters, such as HEPA filters and activated carbon filters, ensuring that the emitted air meets environmental standards. The on / off status and suction intensity of the dust removal system can be dynamically adjusted by an intelligent control and optimization module based on the processing material and laser parameters.

[0038] The gas environment control unit delivers inert gases, such as high-purity nitrogen or argon, or reactive gases, such as oxygen, to the processing area. By controlling the gas environment in the processing area, the chemical reactions during laser ablation can be precisely controlled. An inert gas environment effectively suppresses oxidation reactions of materials at high temperatures, thereby reducing the heat-affected zone, preventing carbonization and oxide formation, and maintaining the cleanliness of hole edges or cutting edges. A reactive gas environment, such as oxygen, can promote the ablation rate of materials under certain conditions, but it requires precise control to avoid excessive oxidation and thermal damage. The gas environment control unit typically includes a high-precision mass flow controller to precisely control the gas type, flow rate, and mixing ratio, ensuring the stability and repeatability of the gas environment in the processing area. Its control parameters are set by an intelligent control and optimization module according to the material type and processing requirements.

[0039] The real-time monitoring and feedback module is used to monitor the dynamic interaction between the laser and the material, as well as the instantaneous morphology of the processing result, in real time and comprehensively throughout the entire laser processing process. This module is the foundation for achieving closed-loop control and adaptive optimization. By providing rich and timely data, it enables the intelligent control and optimization module to sense the processing status and make corresponding adjustments. The real-time monitoring and feedback module includes: a high-speed vision camera, a thermal imager, a spectrometer, and an optical coherence tomography scanner or confocal microscope.

[0040] High-speed vision cameras, including visible light or infrared cameras, are used to observe the plasma plume, material ejection dynamics, and instantaneous morphology of the processed surface generated during laser ablation. High-speed cameras can capture images at thousands to tens of thousands of frames per second, thus capturing the ultrafast dynamics of laser action. By analyzing the shape, size, and brightness of the plasma plume, laser energy coupling efficiency and ablation intensity can be assessed in real time; by observing the direction and velocity of the ejected material, the ablation mechanism and the presence of spatter can be determined. Cameras typically employ high-resolution image sensors and high-brightness illumination, such as coaxial or ring illumination, to ensure image quality. Image data is transmitted to a data preprocessing unit via a high-speed data interface, such as CameraLink or CoaXPress.

[0041] Thermal imagers are used to monitor the local temperature distribution in the processing area in real time. By measuring the radiation intensity of the material surface in the infrared band, thermal imagers can acquire high spatial and temporal resolution temperature field distribution maps non-contactly. By analyzing the range and maximum temperature of the temperature field, the size of the heat-affected zone during laser ablation can be accurately assessed, which is a key indicator for evaluating the effectiveness of "cold" ablation. The data from thermal imagers can be used to build thermal damage prediction models in intelligent control and optimization modules, and as feedback signals, guide the adjustment of laser parameters to suppress heat accumulation.

[0042] Spectrometers are used to analyze the emission spectra of the plasma plume generated during laser ablation. When a laser interacts with a material, the material is vaporized to form a high-temperature, high-pressure plasma containing excited-state atoms and ions. These excited-state particles emit light of characteristic wavelengths when they decay back to their ground state, forming an emission spectrum. By analyzing these spectra, changes in the material composition of the ablated region can be inferred, such as determining the presence of carbide products or oxides. Furthermore, based on the intensity and broadening of specific spectral lines, physical parameters such as plasma temperature and electron density can be deduced, thereby assessing the efficiency and mechanism of laser ablation. Spectrometers are typically triggered synchronously with high-speed cameras to acquire time-resolved spectral data.

[0043] Optical coherence tomography (OCT) or confocal microscopy is used to acquire three-dimensional depth information and precise geometric dimensions of microstructures during or immediately after processing. OCT utilizes the principle of low-coherence interference, measuring the time delay of light beams scattered back from different depths within the material to achieve non-contact tomographic scanning of the material's internal structure, thereby obtaining geometric parameters such as hole depth and diameter, and cut width and depth. Confocal microscopy, on the other hand, uses spatial filtering technology to eliminate the influence of light scattered outside the focal plane, enabling optical slicing and acquiring high-resolution surface morphology and depth information. This three-dimensional geometric data is crucial for ensuring processing accuracy and serves as the direct basis for closed-loop control by the intelligent control and optimization module.

[0044] The real-time monitoring and feedback module preprocesses the collected raw data, including noise suppression, feature extraction, and time synchronization. The noise suppression stage employs digital filtering algorithms, such as median filtering, Gaussian filtering, or Kalman filtering, to eliminate random noise and interference introduced during sensor acquisition. The feature extraction stage extracts key information directly related to processing quality from the raw data, such as aperture edge coordinates, ablation depth, heat-affected zone boundaries, and plasma peak intensity. The time synchronization mechanism ensures precise alignment of data collected by different sensors on the time axis, enabling the intelligent control and optimization module to perform effective multimodal data fusion analysis. The preprocessed data is transmitted to the intelligent control and optimization module with extremely low latency via a high-speed data bus, ensuring real-time feedback.

[0045] The intelligent control and optimization module is the core decision-making and execution unit of the entire single-shot laser drilling system for ultrathin prepreg sheets. It receives processing data from the real-time monitoring and feedback module and dynamically adjusts and optimizes various parameters of the ultrashort pulse laser source module, beam shaping and transmission module, and material handling and positioning module according to preset processing goals, achieving adaptive control of the processing process. The intelligent control and optimization module includes: a high-performance industrial computer, an embedded real-time processor, a process parameter database, and a machine learning or adaptive control engine.

[0046] High-performance industrial computers and embedded real-time processors work together to provide powerful computing capabilities and real-time control response speeds. The high-performance industrial computer handles complex algorithm calculations, user interface interactions, and data storage management. It is typically equipped with a multi-core central processing unit (CPU) and large-capacity random access memory (RAM) to meet the demands of high-speed data processing and complex model calculations. Embedded real-time processors, such as field-programmable gate arrays (FPGAs) or digital signal processors (DSPs), focus on time-critical control tasks, such as precise triggering of laser pulse sequences, trajectory tracking control of galvanometers, and real-time position synchronization of motion platforms. FPGAs achieve extremely low control latency and high-speed data throughput through hardware parallel processing, while DSPs excel at fast digital signal processing and complex control algorithm calculations. These two processors exchange data and coordinate tasks through an internal high-speed communication bus, forming a highly efficient and reliable control core.

[0047] The process parameter database stores optimal laser parameter sets for different types of ultrathin prepreg materials and various microstructure processing targets. This database is built upon extensive experimental data, materials science theory, and historical processing experience. The parameters included are, but are not limited to: typical laser pulse energy ranges, such as microjoules to millijoules; femtosecond or picosecond pulse width settings; kilohertz to megahertz repetition frequency adjustment ranges; spatial spot shapes, such as flat-top, ring, linear, or multi-point array configurations; and temporal pulse sequences, including the relative energy and time intervals of pre-pulse, main pulse, and post-pulse. The database also stores the physicochemical properties of different materials, such as absorption coefficients, ablation thresholds, and thermal diffusivity. When the operator selects a specific material and processing target, the intelligent control and optimization module retrieves and loads a set of validated initial processing parameters from this database as the baseline for system operation. The database is managed using a Structured Query Language (SQL) or NoSQL database management system to ensure efficient data access and reliability.

[0048] The machine learning or adaptive control engine is the core intelligent unit of the intelligent control and optimization module. This engine receives pre-processed real-time processing data from the real-time monitoring and feedback module and compares it with preset target processing parameters. Through an internally deployed pre-trained machine learning model, such as a convolutional neural network, recurrent neural network, or deep learning model, the engine can predict the processing result deviation under the current parameter settings. For example, it can predict the difference between the actual diameter, taper, heat-affected zone size, or burr degree of the cut edge and the target values ​​under the current laser parameter combination.

[0049] Based on the prediction results, machine learning or adaptive control engines implement closed-loop control algorithms to dynamically adjust various parameters of the system. These parameter adjustment commands are sent to the corresponding functional modules in real time. For example, adjusting the output power, pulse width, and pulse repetition frequency of the ultrashort pulse laser source module; adjusting the spatial spot shape and scanning speed of the scanning galvanometer of the beam shaping and transmission module; and adjusting the gas flow rate or type of the gas environment control unit of the material handling and positioning module.

[0050] To ensure precise control and rapid response during the processing, this system employs an adaptive control strategy. The core of this strategy lies in dynamically evaluating the deviation between the processing state and the target, and adjusting the control parameters in real time based on this deviation. The calculation formula for the laser processing parameter adjustment model used to dynamically evaluate the deviation between the processing state and the target is as follows:

[0051] ;

[0052] in, Indicates at time The amount of adjustment required for the current processing parameters Indicates at time From the The error or feature value extracted from real-time monitoring data (such as aperture deviation, heat-affected zone area, etc.). This represents a nonlinear function that maps errors or eigenvalues ​​to the contributions of parameter adjustment. Indicates the first The weighting coefficients for each monitored feature are dynamically learned and adjusted by a machine learning model based on historical data and real-time processing targets. This formula reflects how the system integrates multiple real-time monitoring feedback information to adaptively calculate the optimal parameter adjustment amount.

[0053] The goal of machine learning or adaptive control engines is to achieve adaptive optimization of the machining process. This optimization aims to minimize thermal damage during machining, ensure the geometric accuracy of microstructures, improve machining efficiency, and enhance the robustness and reliability of the system when handling different material types and performing different machining tasks. For example, when the system detects an excessively large heat-affected zone, the engine may instruct the laser source to reduce the single-pulse energy or shorten the pulse width; when the aperture deviates from the target value, the engine may adjust the spot size or scanning speed. The entire optimization process is a continuous feedback loop, enabling the system to learn and correct itself, and always maintain optimal machining conditions.

[0054] Furthermore, for laser cutting tasks, the intelligent control and optimization module includes an advanced trajectory planning algorithm. This algorithm is responsible for generating a smooth, high-speed, and high-precision cutting path based on the target cutting pattern. Trajectory planning considers not only geometric accuracy but also material removal characteristics and laser beam scanning speed. For example, it generates smooth trajectories through spline interpolation or Bézier curves to avoid vibrations and processing defects caused by sudden stops and starts. The algorithm also considers compensation for the kerf width and potential deformation of the cut material to ensure the dimensional accuracy of the final cut part.

[0055] The intelligent control and optimization module also provides an intuitive user interface. This interface allows operators to easily set processing task parameters, including material selection, microstructure type, and dimensional requirements; monitor the processing status in real time, such as displaying real-time video, temperature profiles, and pore size measurement results; and evaluate processing quality, such as providing processing reports, defect analysis, and parameter optimization suggestions. The user interface, through graphical display and interactive control, greatly simplifies the operational complexity of the system.

[0056] The workflow of the entire single-shot laser drilling system for ultrathin prepregs is as follows:

[0057] Operators select the type of ultrathin prepreg material to be processed through an intuitive user interface and input the desired microstructure processing objectives. These objectives include, but are not limited to, the diameter, depth, and taper requirements of the holes; the line width, depth, and smoothness requirements of the cutting edges.

[0058] Upon receiving operator input, the intelligent control and optimization module immediately retrieves and loads the initial processing parameter set corresponding to the selected material and processing target from its built-in process parameter database. These parameters have been verified and optimized through prior experiments and serve as the starting baseline for this processing task.

[0059] Subsequently, the ultrathin prepreg is precisely fixed onto the high-precision chuck of the material handling and positioning module. The chuck, through vacuum or electrostatic adsorption, ensures the material surface maintains extremely high flatness and mechanical stability throughout the entire processing, effectively suppressing any warping or minor vibrations that could lead to processing errors. Next, using a high-resolution XYZ three-axis motion platform, the ultrathin prepreg is accurately moved to the preset processing starting position, and its relative position to the focusing optical system is precisely adjusted via the Z-axis platform to ensure the laser focus is ideally positioned on the material surface.

[0060] The ultrashort pulse laser source module generates laser pulses with specific parameters based on instructions sent by the intelligent control and optimization module. These parameters include pulse width, single pulse energy, repetition frequency, and center wavelength, all of which have been precisely set according to the initial processing parameter set.

[0061] After leaving the laser source module, the laser pulse immediately enters the beam shaping and transmission module. In this module, the laser beam first passes through a beam expander to adjust its diameter, and then its spatial intensity distribution is precisely shaped by a spatial light modulator or diffractive optical element to form the desired processing spot shape, such as a flat-top spot, annular spot, or linear spot. If the time-pulse shaping unit is activated, the laser pulse is further decomposed into a series of sub-pulse sequences with specific time intervals and energy distributions. The shaped laser beam is then physically sized by an aperture, focused by a high numerical aperture telecentric f-θ scanning lens system, and precisely guided to the designated processing surface of the ultrathin prepreg material by a scanning galvanometer.

[0062] The laser beam interacts with the ultrathin prepreg material, completing the formation of microstructures in a single or equivalent single laser event. This process relies on the "cold" ablation mechanism of ultrashort pulses, minimizing thermal damage to the material.

[0063] At the moment of laser irradiation and immediately thereafter, the real-time monitoring and feedback module begins capturing real-time data on the processing and results. A high-speed vision camera observes the plasma plume, material jet dynamics, and the instantaneous morphology of the ablated surface; a thermal imager monitors the local temperature distribution in the processed area in real time; a spectrometer analyzes the emission spectrum of the plasma plume; and an optical coherence tomography scanner or confocal microscope acquires the three-dimensional depth information and geometric dimensions of the formed microstructure. After undergoing preprocessing steps such as noise suppression, feature extraction, and time synchronization within the module, this raw data is rapidly transmitted with extremely low latency to the intelligent control and optimization module for in-depth analysis.

[0064] After receiving real-time monitoring data, the intelligent control and optimization module performs a high-precision comparison with the preset target processing parameters. Through its internal machine learning or adaptive control engine, the system can quickly calculate the deviation between the current processing state and the target. Based on these deviations, the engine uses pre-trained models, such as neural networks, to predict potential processing defects or deficiencies under the current parameter settings.

[0065] Based on the predicted results and real-time deviations, a machine learning or adaptive control engine calculates the optimal parameter adjustment scheme in a very short time. These adjustment schemes are generated through a closed-loop control algorithm and are sent in real-time to the ultrashort pulse laser source module, beam shaping and transmission module, and material processing and positioning module. These instructions may include: adjusting the output power of the laser source to control the ablation depth; changing the pulse repetition frequency to manage the cumulative thermal effect; adjusting the beam shaping unit to generate a new spot shape to optimize the aperture shape; correcting the scanning speed of the scanning galvanometer to adapt to the material ablation rate; and adjusting the gas flow rate or type of the gas environment control unit to optimize the ablation environment.

[0066] To further clarify the decision-making logic of the system in the adaptive control process, especially how the system dynamically adjusts laser parameters to achieve optimization when the processing result deviates from the preset target, an adaptive adjustment strategy for laser single-pulse energy can be considered. When there is a deviation between the microstructure diameter fed back by the real-time monitoring module and the target diameter, the calculation formula for the adaptive adjustment strategy of laser single-pulse energy in the intelligent control and optimization module is as follows:

[0067] ;

[0068] in, This indicates the single-pulse energy of the next laser pulse. This represents the single-pulse energy of the current laser pulse. Indicates at time The diameter of the microstructure was monitored in real time. Indicates the diameter of the target microstructure. It is the proportional gain coefficient. It is the integral gain coefficient. This is the sampling time interval. This formula shows how the system uses a classic proportional-integral (PI) control strategy to dynamically adjust the single-pulse energy of the laser based on the deviation between the real-time measured diameter and the target diameter, as well as the accumulation of historical deviations, in order to achieve precise control of the microstructure dimensions.

[0069] This closed-loop feedback and optimization process will continue until all microstructure processing tasks are completed. Through this efficient, real-time adaptive adjustment mechanism, the system ensures that each laser action meets the preset requirements of high precision, low damage, and high efficiency, thereby significantly improving the overall quality and productivity of ultrathin prepreg processing.

[0070] In summary, the single-shot laser ablation system for ultrathin prepreg sheets proposed in this embodiment achieves "cold" ablation by integrating an ultrashort pulse laser source, significantly reducing the heat-affected zone and defects such as carbonization and delamination. The system utilizes an advanced beam shaping and transmission module, including a spatial light modulator, diffractive optical elements, and a time-pulse shaping unit, to achieve precise control over the laser spot shape and pulse sequence. This allows for the precise shaping of complex microstructures in a single or equivalent single laser event, ensuring the roundness of the hole and the cleanliness of the cutting edges. The system's real-time monitoring and feedback module provides rich and timely process data through multi-sensor in-situ monitoring. The constructed intelligent control and optimization module, with its core machine learning or adaptive control engine, dynamically adjusts laser parameters, beam characteristics, and material processing environment based on real-time feedback data, achieving adaptive optimization of the processing. This closed-loop control mechanism effectively compensates for fluctuations in material and environmental factors, ensuring processing accuracy and stability, and significantly reducing manual intervention and trial-and-error costs. The system, through a material handling and positioning module consisting of a high-precision vacuum chuck, a multi-axis motion platform, and a gas environment control unit, ensures the extreme flatness and precise micron-level positioning of the ultrathin prepreg during processing, providing a stable and reliable physical basis for the precision of laser operation. While improving processing efficiency, this system ensures extremely high processing quality, enabling the ultrathin prepreg to be more widely used in advanced electronic manufacturing fields with stringent requirements for precision and reliability, such as high-density interconnect printed circuit boards, flexible electronics, and chip packaging.

Claims

1. A single-shot laser drilling system for ultrathin prepregs, characterized in that, include: An ultrashort pulse laser source module is used to generate laser pulses with specific parameters; The beam shaping and transmission module is optically connected to the ultrashort pulse laser source module and is used to precisely shape the received laser pulse in space and time, and transmit the shaped laser beam to the surface of the ultrathin prepreg. The material handling and positioning module is used for precise fixing, positioning, and motion control of the ultrathin prepreg. The real-time monitoring and feedback module is used to monitor the interaction between the laser and the material and the processing results in real time during the laser processing process; The intelligent control and optimization module is used to receive data from the real-time monitoring and feedback module, and dynamically adjust and optimize the parameters of the ultrashort pulse laser source module, the beam shaping and transmission module, and the material processing and positioning module according to the preset processing target. The intelligent control and optimization module includes: a high-performance industrial computer, an embedded real-time processor, a process parameter database, and a machine learning or adaptive control engine. The ultrashort pulse laser source module, the beam shaping and transmission module, the material processing and positioning module, the real-time monitoring and feedback module, and the intelligent control and optimization module work together. The beam shaping and transmission module further includes a time pulse shaping unit; the time pulse shaping unit is used to regulate the temporal characteristics of the laser pulse; the time pulse shaping unit is composed of one of a pulse stretcher, a pulse compressor, an electro-optic modulator, or an acousto-optic modulator; the time pulse shaping unit can decompose a laser event into a series of closely connected sub-pulses, forming a pulse cluster or a pre-pulse-main-pulse-post-pulse sequence. By precisely controlling the interval, energy, and duration of the sub-pulses, the system can achieve layer-by-layer removal, preheating, main ablation, and post-processing of materials within an effective single laser action time, thereby optimizing the ablation effect and minimizing thermal damage. A machine learning or adaptive control engine is used to receive real-time monitoring data from the real-time monitoring and feedback module, compare it with preset target processing parameters, and predict the processing result deviation under the current parameter settings through a pre-trained machine learning model. Based on the predicted processing result deviation under the current parameter settings, the machine learning or adaptive control engine implements a closed-loop control algorithm to dynamically adjust the output power, pulse width, and pulse repetition frequency of the ultrashort pulse laser source module, the spot shape and scanning speed of the beam shaping and transmission module, and the ambient gas flow rate of the material processing and positioning module, so as to achieve adaptive optimization of the processing process.

2. The single-shot laser drilling system for ultrathin prepregs according to claim 1, characterized in that, The ultrashort pulse laser source module has laser pulses with ultrashort pulse widths on the order of femtoseconds or picoseconds; the ultrashort pulse laser source module is capable of generating laser output with high peak power and low single pulse energy; the center wavelength of the laser pulse is one of the ultraviolet, visible, or infrared bands; the ultrashort pulse laser source module also has an adjustable pulse repetition frequency and adjustable single pulse energy output capability; furthermore, the ultrashort pulse laser source module ensures that the output laser beam has good beam quality and stability, the beam quality is characterized by a low M² factor, and the stability is characterized by power fluctuations of less than one percent.

3. The single-shot laser drilling system for ultrathin prepregs according to claim 1, characterized in that, The beam shaping and transmission module includes: a beam expander, a spatial light modulator, a diffractive optical element, an aperture, a focusing optical system, and a scanning galvanometer. The beam expander is used to adjust the diameter of the laser beam to match the size requirements of subsequent optical components and ensure the uniformity of the beam when it enters the shaping system. The spatial light modulator or diffractive optical element is used to achieve arbitrary control of the spatial intensity distribution of the laser beam to generate the desired processing spot shape, wherein the processing spot shape includes one of a flat-top spot, annular spot, multi-point array spot, or linear spot. The aperture is used to precisely define the physical size and shape of the laser beam; The focusing optical system is used to focus the shaped laser beam and provide high-precision focusing depth control; The scanning galvanometer is used to enable the laser beam to scan and position itself at high speed and with high precision on the surface of the ultrathin prepreg, so as to complete complex pattern processing paths.

4. The single-shot laser drilling system for ultrathin prepregs according to claim 3, characterized in that, The focusing optical system employs a high numerical aperture telecentric f-θ scanning lens system. This telecentric f-θ scanning lens system ensures that the laser beam has a uniform focused spot size and shape within the working plane. Furthermore, driven by the Z-axis motion platform, it enables micron-level adjustment of the relative position between the laser focusing plane and the surface of the ultrathin prepreg to accommodate materials of different thicknesses or to achieve layer-by-layer processing of multi-layer materials.

5. The single-shot laser drilling system for ultrathin prepregs according to claim 1, characterized in that, The material handling and positioning module includes: a high-precision vacuum chuck or electrostatic chuck, a high-resolution motion platform, a dust removal system, and a gas environment control unit. The high-precision vacuum chuck or electrostatic chuck is used to ensure that the ultra-thin prepreg maintains extremely high flatness and stability during processing, eliminating the impact of warping and vibration on processing accuracy. The high-resolution motion platform is used to achieve nanometer-level positioning accuracy and high-speed motion capability of the ultra-thin semi-cured sheet in three-dimensional space. The dust removal system is used to remove particles and smoke generated during the laser ablation process in real time, preventing them from contaminating optical components or causing secondary pollution to the processing area. The gas environment control unit is used to deliver inert or reactive gas to the processing area to control the chemical environment during the laser ablation process, thereby affecting the ablation rate, the size of the heat-affected zone, and the morphology of the hole edge or cutting edge.

6. The single-shot laser drilling system for ultrathin prepregs according to claim 5, characterized in that, The high-resolution motion platform includes an XYZ three-axis linear motion platform equipped with a high-precision linear encoder. The XY two-axis linear motion platform is used to achieve high-speed and nanometer-level positioning accuracy motion capability of the ultrathin prepreg in a two-dimensional plane. The Z-axis motion platform is used to combine the surface height information provided by the real-time monitoring module to accurately adjust the relative position of the laser focusing plane and the surface of the ultrathin prepreg material, ensuring that the laser focus always falls accurately on the material surface or at a preset depth, thereby maintaining focus consistency during the processing.

7. The single-shot laser drilling system for ultrathin prepregs according to claim 1, characterized in that, The real-time monitoring and feedback module includes: a high-speed visual camera, a thermal imager, a spectrometer, and an optical coherence tomography scanner or a confocal microscope; The high-speed vision camera includes a visible light camera or an infrared camera, used to observe the plasma plume, material jet dynamics, and instantaneous morphology of the processed surface generated during laser ablation. The thermal imager is used to monitor the local temperature distribution in the processing area in real time in order to assess the size of the heat-affected zone; The spectrometer is used to analyze the emission spectrum of plasma plumes, thereby inferring changes in material composition and ablation efficiency. The optical coherence tomography scanner or confocal microscope is used to acquire three-dimensional depth information and precise geometric dimensions of the microstructure during or immediately after processing. The geometric dimensions include the depth and diameter of the hole and the width and depth of the cut. The real-time monitoring and feedback module preprocesses the collected data, including noise suppression, feature extraction, and time synchronization, and then transmits the processed data to the intelligent control and optimization module with extremely low latency.

8. The single-shot laser drilling system for ultrathin prepregs according to claim 1, characterized in that, The high-performance industrial computer and embedded real-time processor provide powerful computing capabilities and real-time control response speed. The embedded real-time processor includes a field-programmable gate array or a digital signal processor. The process parameter database stores the optimal laser parameter set for different types of ultrathin prepreg materials and different microstructure processing targets. The optimal laser parameter set includes pulse energy, pulse width, repetition frequency, spatial spot shape, and time pulse sequence. The machine learning or adaptive control engine is the core intelligent unit of the intelligent control and optimization module.

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