A laser processing system with adjustable optical path

Abstract

The application provides a laser processing system with adjustable light path, and relates to the technical field of laser processing. The two-dimensional scanning mirror, the flat-field lens, the tube lens and the objective lens are arranged on independent moving devices respectively, and are accurately controlled by a control computer, so that they can move forward and backward along the optical axis direction, thereby realizing flexible adjustment of the spacing between these elements. The problems that the system adaptability is poor, the system is difficult to integrate and functionally expand, and the universality and expandability of the system are improved due to the fixed position and relative distance of the optical elements in the existing laser processing system are solved.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of laser processing, in particular to a laser processing system with adjustable optical path. BACKGROUND

[0002] For a highly integrated laser processing system, especially a laser processing system with scanning components such as a galvanometer mirror, a fast mirror and a relay mirror, the installation positions of the optical elements in the optical path are usually strictly limited, and the relative distances between the elements are fixed and unchangeable. If the position of an optical element is changed, spatial interference may occur between the optical elements. If a sensor-related functional component is added, spatial interference may also occur between the original optical elements and the added functional component, so that the laser processing system cannot work normally. Therefore, a system with continuously adjustable positions and relative distances of the optical elements and unchanged laser processing performance is needed to realize adaptive integration with different devices and functional expansion.

[0003] At present, there is no effective technical solution to the above problems. SUMMARY

[0004] The application aims to provide a laser processing system with adjustable optical path, which can continuously adjust the positions and relative distances of the optical elements in the optical path, avoid spatial interference, improve the flexibility and adaptability of the system, and meet more extensive application requirements and functional expansion.

[0005] The application provides a laser processing system with adjustable optical path, which comprises a laser, a beam adjusting device, a two-dimensional scanning mirror, a flat-field lens, a tube lens, an objective lens, a control computer and a sample stage.

[0006] The laser is used for emitting laser beams, and the laser beams pass through the beam adjusting device, the two-dimensional scanning mirror, the flat-field lens, the tube lens and the objective lens in sequence to process a workpiece of the sample stage.

[0007] The two-dimensional scanning mirror, the flat-field lens, the tube lens and the objective lens are arranged on a first moving device, a second moving device, a third moving device and a fourth moving device respectively, and the control computer is used for controlling the first moving device, the second moving device, the third moving device and the fourth moving device to move forward and backward along the optical axis direction respectively, so as to adjust a first distance between the two-dimensional scanning mirror and the flat-field lens, a second distance between the flat-field lens and the tube lens, and a third distance between the tube lens and the objective lens.

[0008] Through the above scheme, the positions and relative distances of the optical elements in the optical path can be continuously adjusted, spatial interference can be avoided, and the flexibility and adaptability of the system can be improved.

[0009] Optionally, the control computer specifically performs the following when adjusting the second distance:

[0010] determining the second distance according to a focal length of the field flattener and a focal length of the tube lens;

[0011] controlling the second moving device and / or the third moving device to move forward and backward along the optical axis direction according to the second distance.

[0012] By the above scheme, the second distance can be accurately adjusted according to the focal length of the optical element, and the light path matching is ensured.

[0013] Optionally, the control computer specifically performs the following when adjusting the first distance and the third distance:

[0014] obtaining a first range of the first distance and a third range of the third distance according to the following three conditions:

[0015] the first condition:

[0016]

[0017] wherein, is the first distance, is the second distance, is the third distance, is a maximum scanning angle corresponding to the field flattener, is a focal length of the field flattener; is a focal length of the tube lens;

[0018] the second condition:

[0019] respectively, the irradiation height of the light beam irradiated on the field flattener, the tube lens and the objective lens is a first height, a second height and a third height, when the laser is output at different scanning angles, each of the first height, each of the second height and each of the third height is less than or equal to a first preset threshold, and the irradiation height is the radial distance between the irradiation position of the light beam and the central axis of the corresponding optical element;

[0020] the third condition:

[0021] the total distance of the first distance, the second distance and the third distance is less than or equal to a second preset threshold.

[0022] By the above scheme, the reasonable range of the first distance and the third distance can be obtained by the preset condition, and the light path performance is further optimized and the light beam is prevented from being cut off.

[0023] Optionally, the maximum scanning angle is calculated according to the following formula:

[0024] ​ ;

[0025] in, ;

[0026] In the formula, The diameter of the processing area. The magnification of the relay lens group consisting of the tube lens and the objective lens is [missing information]. The diameter of the scanning area of ​​the flat-field lens is denoted as .

[0027] Optionally, when the control computer executes the second condition, it specifically performs the following:

[0028] Obtain the different scanning angles of the laser output;

[0029] The first height at which the light beam corresponding to each scanning angle is irradiated by the two-dimensional scanning mirror onto the flat lens is calculated based on each scanning angle and the first spacing.

[0030] The second height at which the light beam corresponding to each scanning angle is irradiated by the flat lens onto the tube mirror is calculated based on each scanning angle, the first spacing, the second spacing, the focal length of the flat lens, and the focal length of the tube mirror.

[0031] The third height at which the light beam corresponding to each scanning angle is irradiated by the objective lens through the tube lens is calculated based on each scanning angle, the first spacing, the third spacing, the focal length of the flat lens, and the focal length of the tube lens.

[0032] Each of the first heights, each of the second heights, and each of the third heights is less than or equal to a first preset threshold.

[0033] The above method can calculate the beam illumination height based on the scanning angle and spacing, ensuring effective beam transmission on the optical element and avoiding beam truncation.

[0034] Optionally, the formula for calculating the first preset threshold is as follows:

[0035] ;

[0036] In the formula, For the first The first preset threshold corresponding to each optical element The light beam illuminates the first The aperture of each optical element The width of the light beam.

[0037] Optionally, each of the first heights is calculated according to the following formula:

[0038] ;

[0039] wherein, is the i-th first height, is the i-th first height, is the i-th scanning angle.

[0040] Optionally, each of the second heights is calculated according to the following formula:

[0041] ;

[0042] wherein, is the i-th second height, is the i-th second height, is the i-th scanning angle.

[0043] Optionally, each of the third heights is calculated according to the following formula:

[0044] ;

[0045] wherein, is the i-th third height, is the i-th third height, is the i-th scanning angle.

[0046] Optionally, the laser processing system further comprises a sensor element or a functional component, which is arranged between the two-dimensional scanning mirror and the flat-field lens.

[0047] As can be seen from the above, the laser processing system with adjustable optical path provided by the present application can realize flexible adjustment of the spacing between the elements by arranging the two-dimensional scanning mirror, the flat-field lens, the tube lens and the objective lens on independent moving devices and precisely controlling them by the control computer to move along the optical axis direction, thereby effectively solving the problem that the poor adaptability, difficulty in integration and functional expansion of the existing laser processing system caused by the fixed position and relative distance of the optical elements, and improving the versatility and expandability of the system.

[0048] Other features and advantages of the present application will be set forth in the following description, and in part will become apparent from the description, or can be learned by practice of the present application. The objects and other advantages of the present application will be realized and attained by the structure particularly pointed out in the written description and claims hereof. BRIEF DESCRIPTION OF DRAWINGS

[0049] Figure 1 FIG. 1 is a structural schematic diagram of a laser processing system with adjustable optical path provided by an embodiment of the present application.

[0050] Figure 2 FIG. 2 is a spacing schematic diagram of a first spacing, a second spacing and a third spacing provided by an embodiment of the present application.

[0051] Figure 3 The range diagram of the second preset threshold provided for the embodiment of the present application.

[0052] Figure 4 The range diagram of the first interval and the third interval provided for the embodiment of the present application.

[0053] Figure 5 The diagram of the effect of the height of the light beam output by the laser processing system with different optical element interval settings on the objective lens changing with the scanning angle provided for the embodiment of the present application.

[0054] Figure 6 The diagram of the position of the temperature and humidity sensor added in the laser processing system with adjustable optical path provided in the present application.

[0055] Label explanation: 1, laser; 2, light beam adjusting device; 3, two-dimensional scanning mirror; 4, flat field lens; 5, tube lens; 6, objective lens; 7, first moving device; 8, second moving device; 9, third moving device; 10, fourth moving device; 11, control computer; 12, sample stage; 13, temperature and humidity sensor. DETAILED DESCRIPTION

[0056] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0057] It should be noted that: similar labels and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. Meanwhile, in the description of the present application, the terms “first”, “second” and the like are only used for distinguishing description, and cannot be understood as indicating or implying relative importance.

[0058] Please refer to Figures 1-6 The present application provides a laser processing system with adjustable optical path, which can realize continuous adjustment of the position and relative distance of each optical element in the optical path, avoid spatial interference, improve the flexibility and adaptability of the system, and meet more extensive application requirements and functional expansion.

[0059] The application provides a laser processing system with adjustable optical path, which comprises a laser 1, a beam adjusting device 2, a two-dimensional scanning mirror 3, a flat-field lens 4, a tube lens 5, an objective lens 6, a control computer 11 and a sample stage 12.

[0060] The laser 1 is used for emitting laser, and the laser beam passes through the beam adjusting device 2, the two-dimensional scanning mirror 3, the flat-field lens 4, the tube lens 5 and the objective lens 6 in sequence to process a workpiece on the sample stage 12.

[0061] The two-dimensional scanning mirror 3, the flat-field lens 4, the tube lens 5 and the objective lens 6 are arranged on a first moving device 7, a second moving device 8, a third moving device 9 and a fourth moving device 10 respectively, and the control computer 11 is used for controlling the first moving device 7, the second moving device 8, the third moving device 9 and the fourth moving device 10 to move forward and backward along the optical axis direction respectively, so as to adjust a first interval between the two-dimensional scanning mirror 3 and the flat-field lens 4, a second interval between the flat-field lens 4 and the tube lens 5 and a third interval between the tube lens 5 and the objective lens 6.

[0062] The laser 1 is used for emitting laser, and the laser beam passes through the beam adjusting device 2, the two-dimensional scanning mirror 3, the flat-field lens 4, the tube lens 5 and the objective lens 6 in sequence to process a workpiece on the sample stage 12.

[0063] Specifically, the system emits laser light through the laser 1, the laser beam is pretreated by the beam adjustment device 2, and then is incident to the two-dimensional scanning mirror 3. The two-dimensional scanning mirror 3 deflects the laser beam so that it can scan the predetermined area. The deflected laser beam passes through the flat-field lens 4, the tube lens 5 and the objective lens 6 in turn, and is finally focused on the workpiece on the sample stage 12 for processing. In order to realize the adjustability of the optical path, the four key optical elements, the two-dimensional scanning mirror 3, the flat-field lens 4, the tube lens 5 and the objective lens 6, are respectively installed on independent moving devices. The first moving device 7 carries the two-dimensional scanning mirror 3, the second moving device 8 carries the flat-field lens 4, the third moving device 9 carries the tube lens 5, and the fourth moving device 10 carries the objective lens 6. The control computer 11 is connected with these moving devices and can send control instructions to them respectively. By driving these moving devices to move back and forth along the optical axis direction through the control computer 11, the system can accurately adjust the first distance between the two-dimensional scanning mirror 3 and the flat-field lens 4, the second distance between the flat-field lens 4 and the tube lens 5, and the third distance between the tube lens 5 and the objective lens 6. This design makes the relative positions of the optical elements no longer fixed, but can be adjusted according to the processing needs or external integration conditions, such as adapting to the optical system space size and shape reserved by different equipment, or upgrading the system to add functional optical elements, sensors, etc., thereby avoiding the space interference that may occur when adjusting the traditional fixed optical path system, and improving the adaptability of the system to different processing tasks and equipment environments.

[0064] Among them, the control computer 11 refers to a computing unit composed of one or more processors, memories and input / output interfaces, which can be realized by an industrial PC, an embedded controller or a special integrated circuit, and is used to execute instructions and process data.

[0065] In some embodiments, when adjusting the second distance, the control computer 11 specifically executes:

[0066] determining the second distance according to the focal length of the flat-field lens 4 and the focal length of the tube lens 5;

[0067] controlling the second moving device 8 and / or the third moving device 9 to move back and forth along the optical axis direction according to the second distance.

[0068] In the laser processing system with adjustable optical path, the control computer 11 first determines the second distance between the flat-field lens 4 and the tube lens 5 based on the focal length of the flat-field lens 4 and the focal length of the tube lens 5 when adjusting the second distance. This step is based on optical principles, as the flat-field lens 4 and the tube lens 5 are usually designed to be placed in confocal, which means the ideal distance between them is the sum of their respective focal lengths to ensure the beam maintains good collimation or focusing properties after passing through both elements. In this way, the determination of the second distance is no longer dependent on experience or trial and error, but is based on the inherent parameters of the optical elements, ensuring the scientificity and accuracy of the adjustment. When the optimal second distance is determined, the control computer 11 will accurately instruct the second moving device 8 carrying the flat-field lens 4 and / or the third moving device 9 carrying the tube lens 5 to move forward and backward along the optical axis direction according to the determined value. This precise physical positioning ensures that the flat-field lens 4 and the tube lens 5 can be accurately placed at the calculated optimal relative position. In this way, the scheme combines optical theory with precise mechanical control, making the optical path adjustment process intelligent and automated, avoiding errors and efficiency problems that may occur in traditional manual adjustment, thereby ensuring the optical path performance and processing quality of the laser processing system under different configurations. This adjustment method combined with the overall optical path adjustability of the system enables the system to adapt to different processing needs and optical configurations, improving the flexibility and versatility of the system.

[0069] In practical applications, when the second distance between the flat-field lens 4 and the tube lens 5 needs to be adjusted, the control computer 11 can read the focal length of the flat-field lens 4 (e.g. ) and the focal length of the tube lens 5 (e.g. ) from its memory in the current system. Then, the control computer 11 can execute a preset calculation program to add these two focal length values, i.e. calculate the second distance = + +. For example, if the focal length of the flat-field lens 4 is 100 mm and the focal length of the tube lens 5 is 200 mm, the control computer 11 can calculate the ideal second distance as 300 mm. After determining the target second distance of 300 mm, the control computer 11 can send control instructions to the second moving device 8 and / or the third moving device 9. The second moving device 8 can be a linear slide driven by a precision stepper motor, with the flat-field lens 4 mounted on it; the third moving device 9 can also be a similar linear slide, with the tube lens 5 mounted on it. The control computer 11 can calculate the distance and direction to be moved based on the deviation between the actual measurement value and the target value of the current second distance, and then accurately control the stepper motor to rotate through pulse signals or serial communication interfaces, thereby driving the corresponding linear slide to move forward and backward along the optical axis direction until the actual distance between the flat-field lens 4 and the tube lens 5 reaches or approaches 300 mm.

[0070] In some embodiments of the present application, the control computer 11 is configured to adjust the relative distances of the optical elements in the optical path, for example, the control computer 11 can determine the second distance according to the focal length of the flat-field lens 4 and the tube lens 5. However, if the first distance and the third distance are adjusted only according to the second distance without considering other key optical and physical constraints, a series of problems can occur. For example, arbitrarily adjusting the first distance and the third distance can cause the laser beam to be truncated when passing through the flat-field lens 4, the tube lens 5 and the objective lens 6, i.e. the radial size of the beam exceeds the effective clear aperture of the optical element, resulting in energy loss, spot distortion, and even damage to the optical element. In addition, if the distances between the optical elements do not meet certain optical relationships, the imaging quality can be reduced or the desired scanning range cannot be achieved. At the same time, the total length of the entire optical path can exceed the physical space limit allowed by the system, causing space interference, making the laser processing system unable to work normally or difficult to integrate into a compact device. Therefore, it is necessary to define the effective range of the first distance and the third distance to ensure that the system remains adjustable in the optical path while maintaining processing performance, avoiding space interference and adapting to physical space limitations.

[0071] In some embodiments, the control computer 11 specifically performs the following when adjusting the first distance and the third distance:

[0072] obtaining a first range of the first distance and a third range of the third distance according to the following three conditions;

[0073] The first condition is:

[0074] (1)

[0075] wherein, is the first distance, is the second distance, is the third distance, is the maximum scanning angle corresponding to the flat-field lens 4, is the focal length of the flat-field lens 4; is the focal length of the tube lens 5;

[0076] The second condition is:

[0077] The irradiation height of the beam on the flat-field lens 4, the tube lens 5 and the objective lens 6 is the first height, the second height and the third height respectively, each first height, each second height and each third height is less than or equal to the corresponding first preset threshold when the laser is output at different scanning angles, and the irradiation height is the radial distance between the beam irradiation position and the central axis of the corresponding optical element (i.e. the flat-field lens 4, the tube lens 5 and the objective lens 6);

[0078] The third condition is:

[0079] The total distance of the first distance, the second distance, and the third distance is less than or equal to a second preset threshold.

[0080] Wherein, the first range of the first distance and the third range of the third distance are obtained according to three conditions, which means that the control computer 11 does not adjust the first distance and the third distance at will, but determines the feasible adjustment interval thereof through a set of preset rules based on optical and physical principles. This method ensures that the optical path can meet the specific performance requirements and physical limitations while being adjustable.

[0081] The first condition defines an optical relationship between the first distance, the second distance, and the third distance. It relates the key distances in the optical path to the maximum scan angle of the flat-field lens 4 and the focal lengths of the flat-field lens 4 and the tube lens 5. The introduction of this formula aims to ensure that the laser beam can maintain the expected optical properties when passing through the optical system during the adjustment of the optical path, such as maintaining the imaging quality or achieving a specific scanning range, especially at the maximum scan angle, the beam can pass through the objective lens 6 correctly.

[0082] The "illumination height" in the second condition is the radial distance between the beam illumination position and the central axis of the flat-field lens 4, the tube lens 5, and the objective lens 6. The "first preset threshold" represents the limitation of the effective clear aperture of the optical element, which is usually half of the element's clear aperture minus the beam radius to ensure that the beam is not truncated by the edge of the element. The core of this condition is that no matter what scan angle the laser outputs, the illumination height on all key optical elements (flat-field lens 4, tube lens 5, objective lens 6) must be less than or equal to the threshold, thereby avoiding beam truncation and ensuring effective transmission of laser energy and spot quality.

[0083] The third condition imposes a physical limitation on the total length of the entire adjustable optical path. The "second preset threshold" represents the maximum total length of the optical path allowed by the system, which is usually determined according to the overall physical space and integration requirements of the laser processing system. By limiting the total distance, it can be ensured that when adjusting the first distance, the second distance, and the third distance, the entire optical path will not exceed the physical space allowed by the system, thereby avoiding physical interference between optical elements and other system components, and ensuring the compactness and integrability of the system.

[0084] In particular, the control computer 11 can pre-store or compute in real-time optical parameters related to the first condition, such as the focal length of the field flattener 4, the focal length of the tube lens 5, and the maximum scan angle corresponding to the field flattener 4. Based on these parameters and the determined second separation, the control computer 11 can derive the relationship that must be satisfied between the first separation and the third separation using the mathematical formula in the first condition. This relationship can be represented as a curve or a region that defines the feasible combinations of the first separation and the third separation in terms of optical performance. Meanwhile, the control computer 11 will take into account the second condition. It will simulate or calculate the radial distances of the laser beam impinging on the field flattener 4, the tube lens 5, and the objective lens 6 at different scan angles, i.e., the first height, the second height, and the third height. These calculations can be performed for a series of discrete scan angles or evaluated through a continuous function. The control computer 11 will compare these calculated impinging heights with the first preset threshold. Only when all simulated or calculated impinging heights are less than or equal to the first preset threshold, the corresponding combination of the first separation and the third separation is considered valid, thereby avoiding beam truncation. In addition, the control computer 11 will also apply the third condition, i.e., ensuring that the sum of the first separation, the second separation, and the third separation does not exceed the second preset threshold. This threshold can be a pre-set maximum physical length, e.g., determined by the maximum available space through system design. The control computer 11 will check in real-time or pre-compute all possible combinations of the first separation and the third separation to ensure that they satisfy the first two conditions while also satisfying this total length limit. By evaluating these three conditions comprehensively, the control computer 11 can determine an intersection region within which the combinations of the first separation and the third separation can guarantee both optical performance and avoid beam truncation, while also conforming to the physical space limitations of the system. The control computer 11 can display this adjustable range to the operator or automatically select a combination and instruct the corresponding moving devices to move the optical elements to the target positions. For example, the control computer 11 can use an iterative algorithm or a numerical optimization method to find a combination of the first separation and the third separation that satisfies all constraints.

[0085] In one specific embodiment, Figure 3 An embodiment of an optical path adjustable laser processing system is provided, which is configured to allow a maximum optical path length (i.e., the second preset threshold) of =1100mm, the positions of the two-dimensional scanning mirror 3, the flat-field lens 4, the tube lens 5, and the objective lens 6 in the system can be adjusted according to actual application needs, wherein the flat-field lens 4 and the tube lens 5 are placed in a confocal manner, and the relative positions of the two do not change during the adjustment process. It is assumed that the light beam width output by the light beam adjusting device 2 is 4mm, and the light beam width in different directions output by the two-dimensional scanning mirror 3 is approximately constant at 4mm. The clear aperture and focal length of the flat-field lens 4 used are 24mm and 300mm respectively, the clear aperture and focal length of the tube lens 5 used are 22mm and 200mm respectively, and the clear aperture and focal length of the objective lens 6 used are 3.5mm and 4mm respectively. It is assumed that the diameter of the region to be processed of the processing sample table 12 is 340μm, and the corresponding maximum scanning angle is 1.62° (calculated according to formula (2)). First, according to formula (4) below, the maximum value of the first spacing between the two-dimensional scanning mirror 3 and the flat-field lens 4 is about 424mm, which is obtained from the clear aperture radius of the flat-field lens 4 (the clear aperture radius is the first height), mm, that is, the first spacing is variable within the range of 0mm-424mm. Convert 1.62° to 0.0283rad, and use formula (1) above to obtain

[0086] ;

[0087] ;

[0088] The value of the third spacing between the tube lens 5 and the objective lens 6 is variable within the range of 144mm-333mm. Further, in order to avoid light cutting, according to the limitation of the clear aperture radius of each element on the light beam height, that is, the first height is less than or equal to 10mm (according to the clear aperture radius of the flat-field lens 4, 12mm, in order to design a safe range, the first height is less than or equal to 10mm, and the second height is less than or equal to 9.66mm (according to the clear aperture radius of the tube lens 5, 11mm, in order to design a safe range, the first height is less than or equal to 9.66mm), it is determined that the effective range of the first spacing is about 237mm-353mm;

[0089] Since the first height mm, it is obtained that ;

[0090] The second height mm, according to formula (5), ;

[0091] It is obtained that ;

[0092] The lower limit of the first spacing of 237mm is determined by the second height being less than or equal to 9.66mm, and the upper limit of the first spacing of 353mm is determined by the first height being less than or equal to 10mm.

[0093] The range of values ​​for the third spacing corresponding to formula (1) is approximately 176mm-227mm (formula (1) is derived from the premise that the third height is 0mm, and naturally satisfies the constraint that the third height is less than or equal to 0.42mm (calculated according to formula (6))).

[0094] ;

[0095] .

[0096] because Therefore, 237 + 500 + 227 = 964; 353 + 500 + 176 = 1029;

[0097] Therefore, the total distance between the first, second, and third spacings varies from approximately 964mm to 1029mm (i.e., the second preset threshold).

[0098] Figure 5 The relationship between the height of the laser beam reaching the objective lens 6 and the scanning angle of the laser processing system with different optical element spacing settings is given. The combination of the first spacing and the third spacing satisfying the relationship (1) is ( , ) = (240.1mm,226.4mm), ( , ) = (290.1mm,204.2mm), ( , ) = (320.2mm,191.0mm), ( , ) = (346.7mm, 179.1mm), from Figure 5 As can be seen, within the scanning angle range of 0-1.62°, the height H of the laser beam varies by 10. -3 The magnitude means that the beam always passes through the center of objective lens 6, and changes in the spacing between optical elements do not affect the laser transmission characteristics and processing performance of the laser processing system.

[0099] The present scheme determines the effective range of the first and third spacings by introducing three key conditions, solving the performance degradation and physical interference problems caused by the adjustment of the optical path in the prior art. Through the first condition, it is ensured that the laser processing system can maintain the expected optical performance when adjusting the spacing of the optical path, such as maintaining the imaging quality and scanning range, avoiding the optical performance degradation caused by the mismatch of the spacing. Through the second condition, the beam truncation of the laser beam when passing through the optical element is effectively avoided, thereby ensuring the effective transmission of the laser energy, reducing the energy loss, and preventing the spot distortion, while protecting the optical element from long-term ablation of the edge beam, improving the stability and consistency of the laser processing. Through the third condition, the total length of the entire adjustable optical path is physically constrained, ensuring that the total length of the optical path does not exceed the maximum physical space allowed by the system, thereby avoiding the physical interference between the optical element and other internal components or the shell of the system, ensuring the compactness, integrability and normal operation of the system, so that the laser processing system can overcome the performance degradation, beam truncation and physical space limitation challenges faced by traditional fixed optical path or simple adjustable optical path while realizing the adjustable optical path, improving the adaptability, reliability and processing quality of the system.

[0100] In some embodiments, the maximum scanning angle is calculated according to the following formula:

[0101] ; (2)

[0102] wherein, ;

[0103] In the formula, is the diameter of the processing area, is the magnification of the relay lens group composed of the tube lens 5 and the objective lens 6, is the scanning area diameter of the flat field lens 4.

[0104] wherein, the scanning area diameter of the flat field lens 4 refers to the maximum radial range that the flat field lens 4 can effectively receive and process the laser beam. The diameter of the processing area refers to the diameter of the largest circular area that the laser processing system can realize processing on the sample table 12. It can be determined according to the actual processing requirements or system design specifications, for example, if it is required to process in a circular area with a diameter of 50 millimeters, the diameter of the processing area can be set to 50 millimeters.

[0105] In the laser processing system, the maximum scanning angle is a key parameter for determining the effective range of the spacing between optical elements, by taking the diameter of the processing area and the magnification of the relay lens group into account ​The calculation ensures that the maximum scanning angle can be adjusted according to actual application requirements, so that the optical path design is consistent with the actual processing target. The accuracy of optical path adjustment is ensured, and the adaptability and performance of the laser processing system are improved.

[0106] In some embodiments, the control computer 11 specifically performs the following when executing the second condition:

[0107] Obtain different individual scanning angles of the laser output;

[0108] Calculate the individual first heights of the light beam irradiated to the flat-field lens 4 by the two-dimensional scanning mirror 3 corresponding to the individual scanning angles according to the individual scanning angles and the first interval;

[0109] Calculate the individual second heights of the light beam irradiated to the tube lens 5 by the flat-field lens 4 corresponding to the individual scanning angles according to the individual scanning angles, the first interval, the second interval, the focal length of the flat-field lens 4 and the focal length of the tube lens 5;

[0110] Calculate the individual third heights of the light beam irradiated to the objective lens 6 by the tube lens 5 corresponding to the individual scanning angles according to the individual scanning angles, the first interval, the third interval, the focal length of the flat-field lens 4 and the focal length of the tube lens 5;

[0111] The individual first heights, the individual second heights and the individual third heights are all less than or equal to the corresponding first preset threshold.

[0112] Wherein, the scanning angle refers to the deflection angle of the laser beam at the two-dimensional scanning mirror 3 relative to the optical axis, which can be obtained by using the control signal of the two-dimensional scanning mirror 3 or the feedback value of the angle sensor. The first preset threshold refers to the maximum radial irradiation distance allowed by the light beam on the optical element, which can be set according to the effective clear aperture of the optical element and the width of the light beam itself, so as to ensure that the light beam will not be truncated when passing through the element.

[0113] Specifically, firstly, the control computer 11 acquires the various scanning angles of the laser output to ensure that the beam behavior across the entire scanning range is considered. Then, based on these scanning angles and the first spacing, it calculates the various first heights at which the beam illuminates the planar lens 4 after passing through the two-dimensional scanning mirror 3. This calculation is a preliminary assessment of the beam behavior at the first critical optical element in the optical path, predicting the radial position of the beam when it enters the planar lens 4. Next, the control computer 11 further calculates the various second heights at which the beam illuminates the tube mirror 5 after passing through the planar lens 4, based on the scanning angle, the first spacing, the second spacing, the focal length of the planar lens 4, and the focal length of the tube mirror 5. This calculation considers the refraction and propagation of the beam after passing through the planar lens 4, as well as the influence of the second spacing and the focal lengths of the two lenses on the beam path, ensuring that the beam remains within the effective light transmission range of the tube mirror 5 when passing through the relay system. Based on this, the control computer 11 continues to calculate the various third heights at which the beam illuminates the objective lens 6 after passing through the tube mirror 5, based on the scanning angle, the first spacing, the third spacing, the focal length of the planar lens 4, and the focal length of the tube mirror 5. This calculation integrates the effects of the spacing between various points in the optical path and the focal length of the optical elements, ensuring that the beam remains within the effective light transmission range of objective lens 6 when it finally enters objective lens 6. This is crucial for guaranteeing the quality and energy transmission efficiency of the final processed spot. Through this technical solution, the control computer 11 can specifically acquire and calculate the illumination height of the beam on each optical element at different scanning angles and verify whether these heights meet preset thresholds. Therefore, the system can accurately determine and adjust the optical path spacing, effectively preventing the laser beam from being truncated on the optical elements or exceeding the effective light transmission aperture, thereby ensuring the stability and reliability of laser processing performance and effectively preventing potential damage to the optical elements.

[0114] In some implementations, the first preset threshold is calculated using the following formula:

[0115] (3)

[0116] In the formula, For the first The optical elements (referring to the two-dimensional scanning mirror 3, the plan lens 4, the tube mirror 5, and the objective lens 6) are: The first preset threshold corresponds to the sequential order of the two-dimensional scanning mirror 3, the flat lens 4, the tube mirror 5, and the objective lens 6. For the beam of light to illuminate the first The aperture of each optical element The width of the beam.

[0117] Light aperture of optical elements This represents the maximum diameter of the light beam that the element can effectively transmit, and its radius. This is the maximum theoretical distance from the center of the laser beam to the edge of the element. However, the laser beam itself has a certain width. This is not an ideal point. Therefore, to ensure that the entire beam, not just the beam center, passes completely through the optical element, the beam width needs to be subtracted from the radius of the aperture. Half of it. Thus, the calculated... This value effectively provides a safety margin for the beam at the edge of the optical element, ensuring that even if the beam hits the edge of the optical element at its maximum scanning angle, its outermost edge will not exceed the effective aperture of the optical element. It is precisely this precise calculation based on the aperture and beam width of the optical element that allows the setting of the first preset threshold to no longer rely on experience or estimation, but rather on objective physical parameters, thus ensuring the scientific validity and applicability of the threshold. In an adjustable laser processing system, when adjusting the optical path spacing, the control computer 11 needs to ensure that the beam's illumination height on the planar lens 4, tube lens 5, and objective lens 6 is less than or equal to this first preset threshold. The calculation method provided in this solution allows for setting a precise and reliable upper limit for these illumination heights. This enables the system to more accurately assess the beam transmission safety at different scanning angles when calculating the range of the first and third spacings, avoiding beam truncation, energy loss, and potential damage to the optical element.

[0118] In some implementations, each first height is calculated according to the following formula:

[0119] (4)

[0120] In the formula, For the first The first height, Let be the i-th scanning angle.

[0121] Through the above calculation formula (4), the control computer 11 can accurately judge and control the beam illumination height, effectively avoiding the beam overflowing the light transmission aperture of the optical element or causing spatial interference, thereby ensuring the stability and processing performance of the laser processing system with adjustable optical path when adjusting the optical path.

[0122] In some implementations, the respective second heights are calculated according to the following formula:

[0123] (5)

[0124] In the formula, For the first The second highest point, Let be the i-th scanning angle.

[0125] Specifically, the second height of the light beam irradiated to the tube lens 5 by the flat-field lens 4 is calculated by the above formula (5), effectively solving the problem that the light beam may exceed the clear aperture of the tube lens 5 due to inaccurate calculation in the prior art. The accurate calculation enables the control computer 11 to reliably determine the radial position of the light beam, thereby effectively avoiding the risk of the light beam being cut off, energy loss, and damage to the optical element. Especially in the laser processing system with adjustable optical path, the present scheme ensures that the system can still maintain stable operation and excellent optical performance under different optical path configurations.

[0126] In some embodiments, each third height is calculated according to the following formula:

[0127] ; (6)

[0128] In the formula, is the i-th third height, is the i-th scanning angle.

[0129] Specifically, by the above formula (6), the laser processing system can accurately obtain each third height of the light beam irradiated to the objective lens 6 by the tube lens 5, so that the control computer 11 can accurately determine whether the light beam will exceed the clear aperture of the objective lens 6, thereby effectively verifying whether the optical path satisfies the condition that the light beam irradiation height is less than or equal to the first preset threshold. Therefore, the accuracy and reliability of the optical path adjustment are significantly improved, and problems such as light beam being cut off, energy loss, or processing quality degradation are avoided, ensuring the normal operation and processing performance of the laser processing system.

[0130] In some embodiments, a sensor element or functional component is further included, which is arranged between the two-dimensional scanning mirror 3 and the flat-field lens 4.

[0131] The sensor element or functional component refers to a component that can provide optical path state information or perform a specific optical function. It can be implemented in various ways, for example, the sensor element can be a light beam position sensor for monitoring the accurate position of the laser beam in the optical path; it can also be a light power meter for real-time measurement of the power of the laser beam; or a temperature sensor, humidity sensor, or vacuum degree sensor, etc. The functional component can be a beam splitter for leading part of the laser beam out for monitoring; or a filter for adjusting the characteristics of the light beam, which is not limited specifically here.

[0132] ​Specifically, the laser processing system adds a sensor element in the original optical path, i.e. between the two-dimensional scanning mirror 3 and the flat-field lens 4. This location selection enables the sensor element to effectively monitor the optical path information, such as real-time acquisition of the power, position or wavelength of the light beam, etc., thereby providing a basis for the intelligent and automated operation of the system. However, in the system with adjustable optical path, the distance between the two-dimensional scanning mirror 3 and the flat-field lens 4 is variable, which may cause physical interference between the newly added sensor element and these movable optical elements. In order to overcome this possible problem, the present scheme sets the sensor element between the two-dimensional scanning mirror 3 and the flat-field lens 4, and ensures that the control computer 11 can comprehensively control the movement devices of all optical elements, thereby solving the space interference problem that may occur when integrating additional functional components in the laser processing system. This enables the system to still achieve optical path adjustment after adding the sensor function, avoids physical interference, and ensures the normal operation of the system. At the same time, the introduction of the sensor element or functional component improves the monitoring and feedback capability of the system, enabling the system to achieve intelligent and automated function improvement, such as real-time optical path calibration or state monitoring, thereby enhancing the functional expandability of the system and improving the adaptive integration capability with different devices.

[0133] In a specific embodiment, as shown in Figure 6 In a specific embodiment, as shown in

[0134] In this document, relational terms such as first and second and the like can be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions.

[0135] The above description is merely illustrative of the application, and not intended to limit the scope of the application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the application shall be included in the scope of the application.

Claims

1. A laser processing system with an adjustable optical path, characterized in that, The laser (1), the beam adjusting device (2), the two-dimensional scanning mirror (3), the flat-field lens (4), the tube lens (5), the objective lens (6), the control computer (11) and the sample stage (12); The laser (1) is used for emitting laser, and the light beam of the laser passes through the beam adjusting device (2), the two-dimensional scanning mirror (3), the flat-field lens (4), the tube lens (5) and the objective lens (6) in turn to process the workpiece on the sample stage (12); The two-dimensional scanning mirror (3), the flat-field lens (4), the tube lens (5) and the objective lens (6) are arranged on the first moving device (7), the second moving device (8), the third moving device (9) and the fourth moving device (10) respectively, and the control computer (11) is used for controlling the first moving device (7), the second moving device (8), the third moving device (9) and the fourth moving device (10) to move back and forth along the optical axis direction respectively, so as to adjust the first distance between the two-dimensional scanning mirror (3) and the flat-field lens (4), the second distance between the flat-field lens (4) and the tube lens (5) and the third distance between the tube lens (5) and the objective lens (6); The control computer (11) specifically performs the following steps when adjusting the second distance: determining the second distance according to the focal length of the flat-field lens (4) and the focal length of the tube lens (5); controlling the second moving device (8) and / or the third moving device (9) to move back and forth along the optical axis direction according to the second distance; The control computer (11) specifically performs the following steps when adjusting the first distance and the third distance: obtaining a first range of the first distance and a third range of the third distance according to the following three conditions; the first condition is that the first height, the second height and the third height are less than or equal to a first preset threshold value when the laser is output at different scanning angles, the first height is the radial distance between the light beam irradiation position and the central axis of the flat-field lens (4), the second height is the radial distance between the light beam irradiation position and the central axis of the tube lens (5), and the third height is the radial distance between the light beam irradiation position and the central axis of the objective lens (6); ； wherein is the first distance, is the second distance, is the third distance, is the maximum scanning angle of the flat field lens (4), is the focal length of the flat field lens (4); is the focal length of the tube lens (5); the second condition is that the first height, the second height and the third height are less than or equal to a second preset threshold value when the laser is output at different scanning angles, the first height is the radial distance between the light beam irradiation position and the central axis of the flat-field lens (4), the second height is the radial distance between the light beam irradiation position and the central axis of the tube lens (5), and the third height is the radial distance between the light beam irradiation position and the central axis of the objective lens (6); the third condition is that the total distance of the first distance, the second distance and the third distance is less than or equal to a second preset threshold value. The maximum scanning angle is calculated according to the following formula: The control computer (11) specifically performs the following steps when performing the second condition:

2. The adjustable optical path laser processing system according to claim 1, wherein, obtaining different scanning angles of the laser output; ； wherein ; wherein is the diameter of the processing region, is the magnification of the relay lens group consisting of the tube lens (5) and the objective lens (6), is the scan field diameter of the flat field lens (4).

3. The adjustable optical path laser processing system according to claim 1, wherein, calculating the first height corresponding to each scanning angle according to each scanning angle and the first distance, the first height being the radial distance between the light beam irradiation position and the central axis of the flat-field lens (4); calculating the second height corresponding to each scanning angle according to each scanning angle, the first distance, the second distance, the focal length of the flat-field lens (4) and the focal length of the tube lens (5), the second height being the radial distance between the light beam irradiation position and the central axis of the tube lens (5); ​ ​ The third height corresponding to each of the scanning angles is calculated according to each of the scanning angles, the first interval, the third interval, the focal length of the field flattening lens (4) and the focal length of the tube lens (5). Each of the first height, the second height and the third height is less than or equal to a corresponding first preset threshold.

4. The adjustable optical path laser processing system according to claim 3, wherein, The first preset threshold is calculated according to the following formula: ； In the formula, is a first preset threshold value corresponding to the first optical element, is a first preset threshold value corresponding to the first optical element, is a first preset threshold value corresponding to the first optical element, is an entrance pupil of the light beam irradiated to the first optical element, is a first preset threshold value corresponding to the first optical element, 5. The adjustable optical path laser processing system according to claim 3, wherein, Each of the first height is calculated according to the following formula: ； wherein is the first height, is the i-th first height, is the i-th scan angle.

6. The adjustable optical path laser processing system according to claim 3, wherein, Each of the second height is calculated according to the following formula: ； wherein is the second height for the i-th is the second height for the i-th is the i-th scan angle.

7. The adjustable optical path laser processing system according to claim 3, wherein, Each of the third height is calculated according to the following formula: ； wherein is the third height for the is the third height for the is the i-th scan angle.

8. The adjustable optical path laser processing system according to claim 1, wherein, The first preset threshold is calculated according to the following formula: Each of the first height is calculated according to the following formula: Each of the second height is calculated according to the following formula: Each of the third height is calculated according to the following formula: The sensor element is arranged between the two-dimensional scanning mirror (3) and the field flattening lens (4).

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