A process control method and system for laser cutting of optical elements

Abstract

The present invention provides a process control method and system for laser cutting of optical components. By real-time monitoring and dynamic compensation for thermal field offsets in transition zones, the method solves the problems of microcracks and edge collapse caused by heat accumulation during laser cutting. The method includes: pre-identifying transition zones in the cutting path and marking key points; real-time monitoring of the thermal field distribution during cutting to obtain the offset and direction of the heat center; dynamically adjusting the laser power and cutting speed according to the offset, and synchronously adjusting the spot position to compensate for the offset according to the offset direction and offset; symmetrically restoring the laser parameters to their initial values ​​after passing the transition center point. The system includes path analysis, thermal field monitoring, control and adjustment, parameter recovery, and execution modules, and the system can implement closed-loop control of the method. The present invention can effectively suppress thermal damage in transition zones during laser cutting, maintain consistency in cutting quality before and after the transition zone, and improve processing yield.

Description

Technical Field

[0001] The present invention relates to the field of laser cutting technology, and in particular to a process control method and system for laser cutting of optical elements. Background Art

[0002] High-precision laser cutting technology for optical components is one of the core processes in the field of optoelectronic manufacturing. Especially with the rapid development of miniaturized devices such as smartphone lenses and AR / VR optical modules, more stringent requirements are placed on the processing quality of brittle materials such as ultra-thin glass and sapphire.

[0003] The industry currently generally uses ultraviolet picosecond lasers for precision cutting, but it still faces severe challenges when processing complex contours. When the cutting path has sharp turns or sharp angles, the laser beam's prolonged residence time at the corner and asymmetric heat diffusion will lead to two key problems: excessive heat accumulation on the inside of the bend forms a local high-temperature zone, while the heat center continues to shift toward the inside of the bend. This unbalanced heat distribution will produce a significant lateral temperature gradient, which in turn induces defects such as microcracks and edge chipping, reducing the fracture strength of the optical component and directly affecting the quality of the finished optical component.

[0004] Existing technologies primarily employ two solutions: one is to reduce heat input by pre-setting the laser power, but fixed-range power adjustment cannot adapt to the varying curvatures of turning areas; the other is to introduce pauses and cooling times at turning points, which significantly reduces machining efficiency and produces noticeable tool marks. Neither approach fundamentally addresses the problem of dynamic thermal field imbalance. Summary of the Invention

[0005] To this end, the technical problem to be solved by the present invention is to overcome the problem of dynamic imbalance of the thermal field in the turning area of ​​laser cutting that has not been fundamentally solved in the prior art, and to provide a process control method for laser cutting of optical elements, which can effectively suppress microcracks and edge collapse caused by heat accumulation by real-time monitoring and dynamic compensation of the heat center offset in the turning area, and at the same time introduce a parameter recovery mechanism to ensure the consistency of laser cutting before and after dynamic compensation in the turning area.

[0006] To solve the above technical problems, the present invention provides a process control method for laser cutting of optical elements, comprising the following steps:

[0007] Before cutting, all curvature changes in the laser cutting path are obtained, and all turning areas on the cutting path are identified according to the curvature changes, and the starting point, center point and end point of each turning area are determined;

[0008] During the cutting process, when the cutting reaches the starting point, the transverse temperature distribution of the laser action area is obtained in real time, and the offset and offset direction of the heat center relative to the laser spot center are identified based on the transverse temperature distribution;

[0009] Dynamically adjust the laser power and cutting speed according to the offset, so that the laser power gradually decreases as the offset increases, and the cutting speed gradually decreases as the offset increases;

[0010] Adjust the laser spot position according to the offset direction and offset amount to compensate for the offset of the heat center;

[0011] When the cutting reaches the center point, the laser power, cutting speed and laser spot position are reversely adjusted with equal amplitude according to the dynamic changes of the laser power, cutting speed and laser spot position between the starting point and the center point, so that when the cutting reaches the end point, the laser power, cutting speed and laser spot position are restored to the initial parameters.

[0012] In one embodiment of the present invention, identifying all turning areas on the cutting path according to the curvature variation includes the following steps:

[0013] Divide the continuous cutting path into path segments of equal length and calculate the curvature change of each path segment, wherein the curvature change is obtained by measuring the angle difference between the tangent directions at both ends of the path segment;

[0014] When the curvature changes of three consecutive path segments all exceed the reference curvature change, the area is determined to be a turning area;

[0015] Extend from the turning area to both sides until a path segment is found where the curvature change is lower than the reference curvature change for the first time, and mark the endpoint of the path segment as the starting point or end point of the turning area;

[0016] After determining that the two end points of the turning area are the starting point and the ending point, the midpoint of the path between the starting point and the ending point is determined as the center point.

[0017] In one embodiment of the present invention, the reference curvature variation is determined by the following steps:

[0018] Perform a standard straight-line cutting test on the target optical component material and record the curvature fluctuation range naturally generated during the cutting process;

[0019] Based on the standard straight line cutting test results, the maximum allowable curvature change when the cutting quality meets the standard is selected as the initial reference value;

[0020] During the actual cutting process, the initial reference value is dynamically corrected based on the cutting quality feedback from real-time monitoring, and the correction range does not exceed ±20% of the initial reference value;

[0021] For cutting areas of different thicknesses, the base curvature change is adjusted according to the thickness ratio. For every 0.1mm increase in thickness, the base value increases by 5%.

[0022] In one embodiment of the present invention, a plane rectangular coordinate system is established with the starting point of the cutting path as the coordinate origin, and the starting point, center point and end point are represented by coordinates in the coordinate system. During the cutting process, the coordinates of each feature point are called in real time to guide the adjustment of process parameters.

[0023] In one embodiment of the present invention, identifying the offset and offset direction of the heat center relative to the laser spot center based on the transverse temperature distribution includes the following steps:

[0024] Taking the theoretical center of the laser spot as the reference point, the detection area is divided into four quadrants. The temperature distribution of each quadrant is scanned in sequence using an infrared thermal imager, and the highest temperature value and corresponding coordinate position in each quadrant are recorded.

[0025] Compare the maximum temperature values ​​of the four quadrants to determine the dominant quadrant with the most concentrated temperature distribution. Within the dominant quadrant, select the area with the largest temperature gradient change as the high-temperature core area, and calculate the geometric center of all high-temperature points in the high-temperature core area as the actual heat center point;

[0026] Connect the theoretical center of the laser spot and the actual heat center to form a baseline, measure the length of the baseline as the offset, take the cutting direction as the reference axis, and measure the angle between the baseline and the reference axis as the offset direction.

[0027] In one embodiment of the present invention, dynamically adjusting the laser power according to the offset comprises the following steps:

[0028] The detected offset is divided into several levels, each level corresponds to a different power adjustment range;

[0029] Determine a basic power value based on the path characteristics of the current cutting position, wherein the basic power value is the minimum power value for achieving quality standards when cutting in a straight line;

[0030] When the offset is within the first level range, the current power remains unchanged;

[0031] When the offset is in the second level range, the power is gradually reduced according to the first adjustment range, and the first adjustment range is 3% to 5% of the current power value;

[0032] When the offset is in the third level range, the power is quickly reduced according to the second adjustment range, which is 6% to 8% of the current power value;

[0033] Power lower limit protection: Set the minimum power threshold to ensure the cutting process continues stably.

[0034] In one embodiment of the present invention, dynamically adjusting the cutting speed according to the offset comprises the following steps:

[0035] Determine the adjustable speed range according to the material type and thickness;

[0036] Establish an offset-speed mapping relationship, including: a small offset interval corresponds to a speed reduction of 5% to 10%; a medium offset interval corresponds to a speed reduction of 11% to 20%; a large offset interval corresponds to a speed reduction of 21% to 30%;

[0037] Set the upper limit of the speed change rate to 5% per second, and use a gradual transition when switching between adjacent offset intervals;

[0038] Monitor changes in cutting surface quality in real time and dynamically optimize the offset-speed mapping relationship based on the cutting effect.

[0039] In one embodiment of the present invention, while adjusting the laser spot position according to the offset direction, auxiliary gas is introduced to adjust the heat offset. According to the offset compensation direction of the laser spot, the injection angle of the auxiliary gas nozzle is synchronously adjusted to align the center line of the gas flow field with the midpoint line position of the compensated laser spot.

[0040] In one embodiment of the present invention, it further comprises:

[0041] Real-time monitoring of the energy fluctuation amplitude and frequency during the cutting process. When the energy fluctuation amplitude exceeds 30% of the normal range and lasts for more than 50ms, it is determined to be an abnormal situation;

[0042] Immediately freeze the current laser power and cutting speed parameters, and keep the laser spot position unchanged in the current compensation state;

[0043] Analyze the temperature distribution change trend of the last 10 sampling cycles, detect whether there is a sudden change in the movement trajectory of the heat center point, and check whether the optical path system is disturbed;

[0044] If the diagnosis is instantaneous interference, the current parameters are maintained and cutting continues; if the diagnosis is persistent abnormality, a gradual parameter rollback mechanism is initiated;

[0045] The laser power is gradually restored to 50% of the original adjustment amount, the cutting speed is synchronously adjusted according to the power recovery ratio, and the spot position is restored last to ensure the stability of the thermal field. After the recovery is completed, the normal adjustment mechanism is re-established.

[0046] The present invention also discloses a process control system for laser cutting of optical elements, comprising:

[0047] The path analysis module is used to obtain all curvature changes in the laser cutting path, identify all turning areas on the cutting path based on the curvature changes, and determine the starting point, center point, and end point of each turning area;

[0048] Thermal field monitoring module, used to obtain the lateral temperature distribution of the laser action area in real time during the cutting process, and identify the offset and offset direction of the heat center relative to the laser spot center when the cutting reaches the starting point;

[0049] The control and regulation module is connected to the thermal field monitoring module and is used to:

[0050] Dynamically adjust the laser power and cutting speed according to the offset, so that the laser power gradually decreases as the offset increases, and the cutting speed gradually decreases as the offset increases;

[0051] Adjust the laser spot position according to the offset direction and offset amount to compensate for the offset of the heat center;

[0052] a parameter recovery module for, when the cutting reaches the center point, reversely adjusting the laser power, cutting speed, and laser spot position with equal amplitude according to the dynamic changes of the laser power, cutting speed, and laser spot position between the starting point and the center point, so that when the cutting reaches the end point, the laser power, cutting speed, and laser spot position are all restored to the initial parameters;

[0053] The execution module is used to execute the instructions of the control and adjustment module and the parameter recovery module to complete the laser cutting operation.

[0054] The above technical solution of the present invention has the following advantages over the prior art:

[0055] The process control method for laser cutting of optical components described in the present invention uses the thermal center offset as the key control mechanism. When the cutting enters the turning zone, the lateral temperature field distribution at the cutting front is captured in real time, and the thermal center offset, including the offset amount and direction, is calculated. This essentially reflects the severity of the thermal field imbalance. Based on this data, three key parameters are synchronously adjusted:

[0056] The laser power and cutting speed are controlled to decrease in proportion to the offset, ensuring sufficient energy to complete the cutting while avoiding heat accumulation.

[0057] According to the offset direction and offset amount, the laser spot position is adjusted to move in the opposite direction of the offset, and the physical influence of the thermal field offset is directly offset through active compensation;

[0058] On the basis of the above-mentioned dynamic regulation, the present invention also introduces a parameter recovery mechanism to control the laser cutting to symmetrically restore the parameters according to the amplitude of reduction in the first half after passing the center point of the turning area. This mirror adjustment method ensures a smooth transition of thermal effects and achieves consistency of laser cutting before and after the turning area, avoiding insufficient cutting after the turning area due to reducing the laser power and cutting speed, and also avoiding secondary thermal shock caused by instantaneously increasing the laser power and cutting speed after the cutting of the turning area is completed. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments of the present invention in conjunction with the accompanying drawings, wherein:

[0060] Figure 1 is a flowchart of the process control method for laser cutting of optical elements of the present invention;

[0061] Figure 2 This is a flowchart of the steps of identifying all turning areas on the cutting path according to the curvature change of the present invention;

[0062] Figure 3 is a flow chart of the steps for determining the reference curvature change amount of the present invention;

[0063] Figure 4 This is a flow chart of the steps of identifying the offset amount and offset direction of the heat center relative to the laser spot center based on the transverse temperature distribution of the present invention;

[0064] Figure 5 is a flow chart of the steps of dynamically adjusting the laser power according to the offset of the present invention;

[0065] Figure 6 is a flow chart of the steps of dynamically adjusting the cutting speed according to the offset amount of the present invention;

[0066] Figure 7 is a flowchart of the steps of the emergency method of the present invention;

[0067] Figure 8 It is a structural block diagram of the process control system for laser cutting of optical elements of the present invention. DETAILED DESCRIPTION

[0068] The present invention will be further described below with reference to the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it. However, the embodiments are not intended to limit the present invention.

[0069] Reference Figure 1 As shown, a process control method for laser cutting of an optical element of the present invention comprises the following steps:

[0070] S10, before cutting, obtaining all curvature changes in the laser cutting path, identifying all turning areas on the cutting path according to the curvature changes, and determining the starting point, center point, and end point of each turning area;

[0071] In this embodiment, by pre-analyzing the geometric features of the cutting path, the turning areas that require special treatment are accurately identified, and the key position points of the control are determined. The purpose of this is to determine precise position information for subsequent real-time control, ensure that the thermal field adjustment can completely correspond to the actual geometric turning, avoid the blindness of the control, and enable subsequent temperature monitoring and parameter adjustment to accurately act on the areas that actually need to be controlled, thereby improving the response accuracy of the entire process control.

[0072] S20. During the cutting process, when the cutting reaches the starting point, the transverse temperature distribution of the laser action area is obtained in real time, and the offset and offset direction of the heat center relative to the laser spot center are identified based on the transverse temperature distribution;

[0073] In the specific implementation process, an infrared thermal imager can be used to capture temperature field information in real time and calculate the offset of the heat center, which can quantify the specific degree and direction of thermal field imbalance and provide accurate input parameters for subsequent dynamic adjustment.

[0074] S30, dynamically adjusting the laser power and cutting speed according to the offset, so that the laser power gradually decreases as the offset increases, and the cutting speed gradually decreases as the offset increases;

[0075] In this embodiment, by establishing a proportional relationship between the offset and the process parameters, precise control of the laser energy input is achieved, and the energy input is adjusted according to the actual degree of thermal field imbalance, which not only ensures the continuity of cutting but also effectively suppresses heat accumulation. Through the dynamic balance control of energy input and heat load, the problem that traditional fixed value adjustment cannot adapt to different curvature turns is avoided, and the problem of inaccurate adjustment of laser cutting parameters according to the bending angle in the existing technology is further solved, which significantly reduces the risk of thermal damage.

[0076] S40, adjusting the laser spot position according to the offset direction and offset amount to compensate for the offset of the heat center;

[0077] In a specific implementation process, the present invention also directly intervenes in the distribution state of the thermal field by actively adjusting the position of the light spot. Adjusting the position of the light spot can directly physically offset the influence of the thermal field offset, thereby improving the symmetry of the thermal distribution.

[0078] Furthermore, in the above steps, due to the local excessive temperature caused by the offset of the heat center, heat accumulation is suppressed by reducing the laser power and cutting speed. However, this adjustment will form different process parameters in the turning area than in the straight section. After laser cutting the turning area, the different process parameters will lead to different cutting quality before and after the turning area. To solve this problem, the present invention also adopts a mirror-symmetric parameter recovery method:

[0079] S50, when the cutting reaches the center point, according to the dynamic changes of the laser power, cutting speed and laser spot position between the starting point and the center point, the laser power, cutting speed and laser spot position are reversely adjusted with equal amplitude, so that when the cutting reaches the end point, the laser power, cutting speed and laser spot position are restored to the initial parameters;

[0080] In this embodiment, the magnitude of the parameter reduction in the first half of the process is used as a benchmark, and an equal and opposite adjustment is made in the second half. This ensures a symmetrical distribution of energy input in the transition zone, avoiding secondary thermal shock or fluctuations in cutting quality caused by sudden parameter changes. This achieves a smooth transition of process conditions, eliminating the risk of thermal damage caused by parameter reduction in the first half of the process while ensuring process stability during the second half of the process, ensuring that the cutting quality throughout the transition zone remains consistent with that of the straight line segment. This symmetrical recovery mechanism is particularly suitable for materials sensitive to thermal shock, such as ultra-thin optical glass, and can maintain processing efficiency while controlling thermal effects.

[0081] Reference Figure 2 As shown, in this embodiment, the continuous cutting path is discretized to achieve accurate capture of the turning features in the complex path, providing an accurate geometric reference for subsequent temperature control and parameter adjustment. The specific implementation process includes:

[0082] S11, path feature analysis: Divide the continuous cutting path into path segments of equal length, and calculate the curvature change of each path segment. The curvature change is obtained by measuring the angle difference between the tangent directions at both ends of the path segment;

[0083] S12, turning area determination: when the curvature changes of three consecutive path segments all exceed the reference curvature change, the area is determined to be a turning area;

[0084] S13, determining the boundary of the turning area: extending from the turning area to both sides until a path segment is found where the curvature change is lower than the reference curvature change for the first time, and marking the endpoint of the path segment as the starting point or the ending point of the turning area;

[0085] S14. Determine the center point of the turning area: After determining that the two end points of the turning area are the starting point and the ending point, the midpoint of the path between the starting point and the ending point is determined as the center point.

[0086] From the perspective of technical effects, the recognition method of this embodiment can accurately capture the turning features of various complex shapes through multi-level criteria and boundary extension mechanism. Its discretization processing method is particularly suitable for the digital control requirements of CNC systems, and the calculation method based on tangent angle difference greatly reduces the resource consumption of real-time calculation, and can achieve rapid response while maintaining high precision; each step is closely linked, from path discretization to curvature calculation, from area determination to boundary confirmation, and finally completing key point positioning, forming a complete and reliable turning area recognition system, which lays a solid foundation for the subsequent dynamic adjustment of process parameters.

[0087] Reference Figure 3 As shown, in order to further improve the above technical solution and realize the application of the above solution in the process, this embodiment further discloses how to determine the reference curvature change, including:

[0088] S121, Standard Straight Cutting Test: Perform a standard straight cutting test on the target optical component material to record the curvature fluctuation range naturally generated during the cutting process. This basic test eliminates the influence of equipment errors and material unevenness, providing an objective basis for setting benchmark values.

[0089] S122, determining an initial reference value: Based on the standard straight line cutting test results, selecting the maximum allowable curvature change when the cutting quality meets the standard as the initial reference value, ensuring that the true turning characteristics are retained to the greatest extent possible while ensuring the cutting quality;

[0090] S123, dynamic optimization adjustment: During the actual cutting process, the initial reference value is dynamically corrected based on the real-time monitoring of cutting quality feedback, and the correction range does not exceed ±20% of the initial reference value. This adaptive capability effectively copes with uncertainties in the processing process, such as material batch differences or ambient temperature fluctuations.

[0091] S124. Thickness differentiation adjustment: For cutting areas of different thicknesses, the base curvature change is adjusted according to the thickness ratio. For every 0.1mm increase in thickness, the base value is increased by 5%. This on-demand adjustment method accurately reflects the influence of material thickness on cutting deformation characteristics.

[0092] In this embodiment, this benchmark value determination method combines experimental testing with theoretical calculations, which not only ensures the objectivity of the parameters but also takes into account practicality. Among them: the dynamic correction mechanism gives the adaptability to complex working conditions, and the adjustment for thickness changes reflects the scientific nature of the parameter setting and the applicability of the method to products of different materials.

[0093] Specifically, from basic testing to practical application, from static setting to dynamic optimization, a complete parameter determination system has been formed, which provides reliable technical support for turning area identification, ensuring that the real turning features can be accurately identified under various working conditions, avoiding misjudgment or missed detection. It not only improves the accuracy of turning identification, but also provides a guarantee for the stability of the entire cutting process, so that subsequent temperature control and parameter adjustment can be based on accurate geometric features.

[0094] In this embodiment, in order to connect the determined geometric features (starting point, center point, and end point) with the digitalization of process control, a standardized coordinate system is established to convert the starting point, center point, and end point of the turning area into quantifiable coordinate parameters, thereby providing a spatial reference for the precise control of the entire cutting process. Specifically, the design of establishing a plane rectangular coordinate system with the starting point of the cutting path as the coordinate origin not only conforms to the conventional operating logic of the CNC machining system, but also ensures the uniqueness and stability of the coordinate system, avoiding positioning errors caused by changes in the reference system. The method of representing feature points with coordinates is essentially to convert the identified geometric features into digital instructions that can be recognized by the machine. This digital conversion enables subsequent process parameter adjustments to establish a precise correspondence with the spatial position. The mechanism of real-time calling of coordinate data during the cutting process ensures strict synchronization between process control and geometric position. This spatiotemporal consistency is particularly critical for the precise processing of the turning area.

[0095] In this embodiment, this coordinate processing method eliminates the benchmark differences between different processes by establishing a unified spatial reference system; binds the feature point coordinates to the process parameters to achieve precise position-based control; and the real-time calling mechanism ensures the timeliness of the control. From the establishment of the coordinate system to the determination of the coordinates, and then to the data call, a complete spatial positioning control chain is formed, so that the identified turning features can be accurately converted into control instructions to guide the precise adjustment of parameters such as laser power and cutting speed.

[0096] This coordinate-based control method not only improves the accuracy of process execution, but also enhances the repeatability of the method, providing reliable guarantees for the stable processing of complex paths, so that temperature control and parameter compensation can be accurately implemented in the correct spatial position.

[0097] Reference Figure 4 As shown, in this embodiment, in order to achieve accurate quantification of thermal field asymmetry during laser cutting, a method for identifying the offset of the center of gravity of the thermal field is provided, including:

[0098] S21. Temperature field partition scanning: The design of dividing the field into four quadrants based on the theoretical center of the laser spot creatively transforms the complex thermal field distribution problem into a structured data analysis problem. This partition processing method not only improves detection efficiency, but also enhances the reliability of the results through comparative analysis between quadrants. An infrared thermal imager is used to scan the temperature distribution of each quadrant in turn and record the highest temperature value and position. This method not only ensures the comprehensiveness of data collection, but also reduces the complexity of data processing through key feature extraction.

[0099] S22. Heat center positioning: The dominant quadrant is determined by comparing the highest temperature values ​​in the four quadrants. The area with the largest temperature gradient change in the dominant quadrant is selected as the high-temperature core area for design. The physical characteristic of temperature gradient is used to identify the true center of heat influence, avoiding the misjudgment that may be caused by relying solely on absolute temperature values. Furthermore, the geometric center of the high-temperature core area is calculated as the actual heat center point, and the interference of local abnormal points is effectively eliminated through multi-point averaging.

[0100] S23. Determination of offset parameters: The operation of connecting the theoretical center and the actual center to form a baseline converts the abstract thermal field offset into an intuitive geometric quantity, which is convenient for subsequent parameter adjustment. Measuring the length of the baseline as the offset can reflect the degree of thermal field imbalance, and measuring the angle between the baseline and the reference axis with the cutting forward direction as the reference axis as the offset direction can accurately capture the spatial orientation of the offset.

[0101] In this embodiment, this thermal field analysis method significantly improves the accuracy of heat center positioning through structured partitioning and gradient feature recognition, converts temperature distribution into geometric parameter design, and forms a strict thermal field detection chain from area division to data acquisition, from feature analysis to parameter calculation, so that thermal field regulation can be based on precise quantification, ensuring that the adjustment of parameters such as laser power and cutting speed can accurately correspond to the actual heat distribution state, thereby effectively improving the cutting quality of the turning area.

[0102] Reference Figure 5 As shown, in order to further guide the application of the process, the present invention also discloses a preferred process for dynamically adjusting the laser power according to the offset, including:

[0103] S301. Offset grading: The detected offset is divided into several levels, each level corresponds to a different power adjustment range, and the continuous physical quantity change is converted into a discrete control strategy, so that the power adjustment can accurately match the offset conditions of different degrees.

[0104] S302. Power benchmark setting: Determine the basic power value based on the current cutting position path characteristics. The basic power value is the minimum power value that meets the quality standard when cutting straight lines, and fully considers the differences in energy requirements of different geometric shapes. This position-based energy benchmark setting ensures the rationality of power regulation.

[0105] S303, power adjustment execution: When the offset is within the first level range, in actual processes, the first level range can be quantified as 0.1mm to 0.3mm depending on different optical components. An offset within this range does not affect product quality. Therefore, the strategy of maintaining a constant laser power avoids overreaction to minor fluctuations and improves process stability.

[0106] When the offset is in the second level range, which can be quantified as 0.3mm to 0.6mm depending on the optical element, the laser power is gradually reduced by 3% to 5%, achieving precise compensation for moderate thermal offset. This gradual adjustment ensures timely thermal control and avoids cutting instability caused by sudden power changes.

[0107] When the offset is in the third level range, in actual processes, the third level range can be quantified as: greater than 0.6mm, depending on different optical elements, the laser power is quickly reduced by 6% to 8%, which can timely suppress the risk of severe heat accumulation;

[0108] This graded response mechanism improves adaptability to thermal excursions of varying severity.

[0109] S304, power lower limit protection: Set the minimum power threshold to ensure that the cutting process continues stably, essentially preventing the cutting interruption caused by too low power, and providing reliable protection for the process.

[0110] In this embodiment, this hierarchical power regulation method realizes the organic combination of thermodynamic process and process control by establishing a precise correspondence between offset and power change; the basic power setting based on path characteristics ensures the rationality of energy input; and the multi-level response mechanism gives it the adaptability to cope with different working conditions.

[0111] Specifically, a complete power control chain is formed from offset grading to power benchmark determination, and from graded adjustment to safety protection, so that thermal field regulation can be achieved through precise power matching, ensuring that the laser energy input always maintains a dynamic balance with the thermal load of the material.

[0112] Similarly, refer to Figure 6 As shown, the present invention also discloses a preferred process for dynamically adjusting the cutting speed according to the offset, including:

[0113] S311. Speed ​​adjustment interval division: The speed adjustable range is determined according to the material type and thickness. First, the difference in sensitivity of different materials to heat input is considered. By pre-setting a reasonable speed adjustment interval, a safety margin is provided for subsequent dynamic adjustment. This parameter setting based on material characteristics can effectively prevent cutting quality problems caused by improper speed adjustment.

[0114] S312. Establish an offset-speed mapping relationship: Set a small offset range (0.1-0.3mm) to a speed reduction of 5%-10%, a medium offset range (0.3-0.5mm) to a speed reduction of 11%-20%, and a large offset range (>0.5mm) to a speed reduction of 21%-30%. This graded mapping design enables speed adjustment to accurately match different degrees of offset. Specifically, the offset-speed mapping relationship is determined through experiments, achieving a balance between heat input and material removal rate while ensuring product cutting quality.

[0115] S313, speed adjustment control: set the upper limit of speed change rate to 5% per second, and adopt gradual transition when switching between adjacent offset intervals. This measure effectively prevents cutting instability caused by sudden speed changes. The gradual transition ensures smooth changes in process parameters and avoids fluctuations in cutting quality caused by parameter jumps.

[0116] S314, Dynamic Optimization Mapping Relationship: A closed-loop control mechanism that monitors changes in cutting surface quality in real time and dynamically optimizes the offset-speed mapping relationship based on the cutting effect gives it self-learning optimization capabilities. By continuously fine-tuning control parameters through continuous quality feedback, it can adapt to the differences in characteristics of different batches of materials and changes in the processing environment.

[0117] In this embodiment, this speed regulation method achieves precise matching of process parameters and thermodynamic states by establishing an accurate mapping relationship between physical quantities; the limitation of speed change rate ensures process stability; and the real-time optimization mechanism enables it to have the ability of continuous improvement.

[0118] Specifically, from parameter range setting to mapping relationship establishment, from change rate control to real-time optimization, a complete speed control system has been formed, which enables thermal field management to be achieved through intelligent speed adjustment, ensuring that the cutting process is always in the optimal thermodynamic equilibrium state.

[0119] In the laser cutting process, the auxiliary gas not only assumes the basic function of removing the molten material, but its flow characteristics also play an important regulatory role in the temperature distribution of the cutting area. The application position of the auxiliary gas in the existing technology is fixed. However, in this embodiment, since the position of the laser spot is adjusted in real time, it is also necessary to adjust the application position of the auxiliary gas according to the position change of the laser spot, ensuring that the center line of the gas flow field is accurately aligned with the midpoint line of the compensated laser spot, so that the auxiliary gas can act most effectively on the thermal offset area.

[0120] Specifically, when a shift in the heat center is detected, the direction and distance of the laser spot that needs to be compensated are first determined, and then the gas nozzle is driven to adjust the corresponding angle. This linkage control ensures that the gas jet always points to the area that most needs heat dissipation. On the one hand, it enhances the slag discharge efficiency and prevents secondary heat conduction; on the other hand, targeted cooling of high-temperature areas is achieved through directional airflow, effectively balancing the temperature distribution.

[0121] This collaborative adjustment method significantly improves the thermal compensation effect through the precise matching of gas flow and laser spot position. From offset detection to spot compensation, from nozzle adjustment to flow field optimization, a complete thermal management closed loop is formed, which enables thermal field control to be achieved through multiple physical means, significantly improving the cutting quality in the turning area.

[0122] During the laser cutting process of precision optical components, due to factors such as uneven material microstructure, environmental vibration or transient equipment failure, special situations such as abnormal energy fluctuations may occur. These emergencies will have a serious impact on the cutting quality. Therefore, this embodiment also provides an emergency treatment method, referring to Figure 7 As shown, including:

[0123] S61, abnormal situation identification: Real-time monitoring of energy fluctuation amplitude and frequency during the cutting process. When the fluctuation amplitude exceeds the normal range by 30% and lasts for 50ms, it is determined to be an abnormal situation. The dual judgment design ensures the sensitivity of abnormality identification and avoids the occurrence of false alarms.

[0124] S62. Parameter stabilization processing: Immediately freezing the current process parameters can effectively prevent the abnormal condition from further deteriorating, buying valuable time for diagnosis, and keeping the laser spot position unchanged maintains the relative stability of the thermal field.

[0125] S63. Diagnosis of abnormal causes: By analyzing the temperature distribution change trend of the last 10 sampling cycles, detecting the movement trajectory of the heat center point, and checking the status of the optical path system, this multi-angle diagnostic method can accurately distinguish between transient interference and persistent abnormalities.

[0126] S64. Recovery strategy selection: For instantaneous interference, the strategy of maintaining the current parameters and continuing cutting is selected, which reflects the fault tolerance ability to short-term fluctuations; and for persistent anomalies, a progressive parameter fallback mechanism is activated. This hierarchical processing method ensures both safety and production efficiency.

[0127] S65, safe recovery: The design of gradually restoring the laser power by 50% of the original adjustment amount realizes a smooth transition of energy. The cutting speed is adjusted synchronously according to the power recovery ratio to maintain the coordination and consistency of process parameters. Finally, the spot position is restored to ensure the ultimate stability of the thermal field.

[0128] The entire exception handling mechanism, from real-time monitoring to rapid response, from precise diagnosis to hierarchical processing, and finally to smooth recovery, forms a complete emergency management closed loop, so that the process method of this embodiment can still guarantee processing quality in the face of emergencies.

[0129] Reference Figure 8 As shown, in order to implement the above method, the present invention also discloses a process control system for laser cutting of optical elements, comprising:

[0130] The path analysis module is used to obtain all curvature changes in the laser cutting path, identify all turning areas on the cutting path based on the curvature changes, and determine the starting point, center point, and end point of each turning area;

[0131] Thermal field monitoring module, used to obtain the lateral temperature distribution of the laser action area in real time during the cutting process, and identify the offset and offset direction of the heat center relative to the laser spot center when the cutting reaches the starting point;

[0132] The control and regulation module is connected to the thermal field monitoring module and is used to:

[0133] Dynamically adjust the laser power and cutting speed according to the offset, so that the laser power gradually decreases as the offset increases, and the cutting speed gradually decreases as the offset increases;

[0134] Adjust the laser spot position according to the offset direction and offset amount to compensate for the offset of the heat center;

[0135] a parameter recovery module for, when the cutting reaches the center point, reversely adjusting the laser power, cutting speed, and laser spot position with equal amplitude according to the dynamic changes of the laser power, cutting speed, and laser spot position between the starting point and the center point, so that when the cutting reaches the end point, the laser power, cutting speed, and laser spot position are all restored to the initial parameters;

[0136] The execution module is used to execute the instructions of the control and adjustment module and the parameter recovery module to complete the laser cutting operation.

[0137] The process control system for laser cutting of optical elements of this embodiment can realize the process control method for laser cutting of optical elements in the above embodiments. The specific implementation process refers to the description of the above embodiments and will not be repeated here.

[0138] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present application may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0139] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0140] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0141] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0142] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will appreciate that other variations or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A process control method for laser cutting of optical components, characterized by: The following steps are involved: Before cutting, all curvature changes in the laser cutting path are obtained, all turning areas on the cutting path are identified according to the curvature changes, and the starting point, center point and end point of each turning area are determined; including: dividing the continuous cutting path into path segments of equal length, calculating the curvature change of each path segment, and the curvature change is obtained by measuring the angle difference in the tangent direction at both ends of the path segment; when the curvature changes of three consecutive path segments all exceed the reference curvature change, the area is determined to be a turning area; extending from the turning area to both sides until a path segment is found where the curvature change is lower than the reference curvature change for the first time, marking the end point of the path segment as the starting point or end point of the turning area; after determining that the two end points of the turning area are the starting point and the end point respectively, the midpoint of the path between the starting point and the end point is determined as the center point; During the cutting process, when the cutting reaches the starting point, the lateral temperature distribution of the laser action area is obtained in real time, and the offset and offset direction of the heat center point relative to the laser spot center are identified according to the lateral temperature distribution; including: taking the theoretical center of the laser spot as the reference point, dividing the detection area into four quadrants, using an infrared thermal imager to scan the temperature distribution of each quadrant in turn, and recording the highest temperature value and the corresponding coordinate position in each quadrant; comparing the highest temperature values ​​of the four quadrants, determining the dominant quadrant with the most concentrated temperature distribution, and in the dominant quadrant, selecting the area with the largest temperature gradient change as the high-temperature core area, calculating the geometric center of all high-temperature points in the high-temperature core area as the actual heat center point; connecting the theoretical center of the laser spot and the actual heat center point to form a baseline, measuring the length of the baseline as the offset, taking the cutting forward direction as the reference axis, and measuring the angle between the baseline and the reference axis as the offset direction; Dynamically adjust the laser power and cutting speed according to the offset, so that the laser power gradually decreases as the offset increases, and the cutting speed gradually decreases as the offset increases; including: dividing the detected offset into several levels, each level corresponding to a different power adjustment range; determining a basic power value according to the path characteristics of the current cutting position, the basic power value is the minimum power value that meets the quality standard when cutting in a straight line; when the offset is in the first level range, keep the current power unchanged; when the offset is in the second level range, gradually reduce the power according to the first adjustment range, the first adjustment range is 3% to 5% of the current power value; when the offset is in the third level range, quickly reduce the power according to the second adjustment range, the second adjustment range is 6% to 8% of the current power value; power lower limit protection: set a minimum power threshold to ensure that the cutting process is continuous and stable; Adjust the laser spot position according to the offset direction and offset amount to compensate for the offset of the heat center; When the cutting reaches the center point, the laser power, cutting speed and laser spot position are reversely adjusted with equal amplitude according to the dynamic changes of the laser power, cutting speed and laser spot position between the starting point and the center point, so that when the cutting reaches the end point, the laser power, cutting speed and laser spot position are restored to the initial parameters.

2. The process control method for laser cutting of optical components according to claim 1, characterized in that: The reference curvature variation is determined by the following steps: Perform a standard straight-line cutting test on the target optical component material and record the curvature fluctuation range naturally generated during the cutting process; Based on the standard straight line cutting test results, the maximum allowable curvature change when the cutting quality meets the standard is selected as the initial reference value; During the actual cutting process, the initial reference value is dynamically corrected based on the cutting quality feedback from real-time monitoring, and the correction range does not exceed ±20% of the initial reference value; For cutting areas of different thicknesses, the base curvature change is adjusted according to the thickness ratio. For every 0.1mm increase in thickness, the base value increases by 5%.

3. The process control method for laser cutting of optical components according to claim 1, characterized in that: With the starting point of the cutting path as the coordinate origin, a plane rectangular coordinate system is established, and the starting point, center point and end point are represented by coordinates in the coordinate system. During the cutting process, the coordinates of each feature point are called in real time to guide the adjustment of process parameters.

4. The process control method for laser cutting of optical components according to claim 1, characterized in that: Dynamically adjusting the cutting speed according to the offset includes the following steps: Determine the adjustable speed range according to the material type and thickness; Establish an offset-speed mapping relationship, including: a small offset interval corresponds to a speed reduction of 5% to 10%; a medium offset interval corresponds to a speed reduction of 11% to 20%; a large offset interval corresponds to a speed reduction of 21% to 30%; Set the upper limit of the speed change rate to 5% per second, and use a gradual transition when switching between adjacent offset intervals; Monitor changes in cutting surface quality in real time and dynamically optimize the offset-speed mapping relationship based on the cutting effect.

5. The process control method for laser cutting of optical components according to claim 1, characterized in that: While adjusting the laser spot position according to the offset direction, auxiliary gas is also introduced to adjust the heat offset. According to the offset compensation direction of the laser spot, the injection angle of the auxiliary gas nozzle is synchronously adjusted to align the center line of the gas flow field with the midpoint line position of the compensated laser spot.

6. The process control method for laser cutting of optical components according to claim 1, characterized in that: Also includes: Real-time monitoring of the energy fluctuation amplitude and frequency during the cutting process. When the energy fluctuation amplitude exceeds 30% of the normal range and lasts for more than 50ms, it is determined to be an abnormal situation; Immediately freeze the current laser power and cutting speed parameters, and keep the laser spot position unchanged in the current compensation state; Analyze the temperature distribution change trend of the last 10 sampling cycles, detect whether there is a sudden change in the movement trajectory of the heat center point, and check whether the optical path system is disturbed; If the diagnosis is instantaneous interference, the current parameters are maintained and cutting continues; if the diagnosis is persistent abnormality, a gradual parameter rollback mechanism is initiated; The laser power is gradually restored to 50% of the original adjustment amount, the cutting speed is synchronously adjusted according to the power recovery ratio, and the spot position is restored last to ensure the stability of the thermal field. After the recovery is completed, the normal adjustment mechanism is re-established.

7. A process control system for laser cutting of optical elements, used to implement the process control method according to any one of claims 1 to 6, characterized in that: include: The path analysis module is used to obtain all curvature changes in the laser cutting path, identify all turning areas on the cutting path based on the curvature changes, and determine the starting point, center point, and end point of each turning area; Thermal field monitoring module, used to obtain the lateral temperature distribution of the laser action area in real time during the cutting process, and identify the offset and offset direction of the heat center relative to the laser spot center when the cutting reaches the starting point; The control and regulation module is connected to the thermal field monitoring module and is used to: Dynamically adjust the laser power and cutting speed according to the offset, so that the laser power gradually decreases as the offset increases, and the cutting speed gradually decreases as the offset increases; Adjust the laser spot position according to the offset direction and offset amount to compensate for the offset of the heat center; a parameter recovery module for, when the cutting reaches the center point, reversely adjusting the laser power, cutting speed, and laser spot position with equal amplitude according to the dynamic changes of the laser power, cutting speed, and laser spot position between the starting point and the center point, so that when the cutting reaches the end point, the laser power, cutting speed, and laser spot position are all restored to the initial parameters; The execution module is used to execute the instructions of the control and adjustment module and the parameter recovery module to complete the laser cutting operation.

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