A laser processing system and method for brittle materials

Abstract

The application belongs to the technical field of laser processing, and relates to a brittle material laser processing system and a processing method. The brittle material laser processing system comprises a first processing assembly. The first processing assembly is used for forming a modified zone on a workpiece to be processed along a preset processing path. In a first direction, the first processing assembly comprises a first laser and a phase modulation unit arranged in sequence. The first laser is used for emitting a first light beam. The phase modulation unit is used for modulating the first light beam emitted from the laser to obtain a modulated light beam with long focal depth and an elliptical spot. The modulated light beam is used for being emitted to the workpiece to be processed to process the workpiece to be processed. The technical scheme provided by the laser processing system and the processing method can reduce the probability of edge collapse when processing the workpiece to be processed, and make the cross section uniform.

Description

Technical Field

[0001] The present invention relates to the field of laser processing technology, and in particular to a laser processing system and method for brittle materials. Background Art

[0002] With the continuous development of the electronics industry, most of the panel materials used in electronic products are brittle materials. Common hard and brittle materials include sapphire, glass, ceramics, etc.

[0003] Currently, the processing methods for brittle materials such as glass primarily involve machine tool processing or laser processing. Laser processing is widely used due to its non-contact, simple operation, and high flexibility. However, conventional laser processing techniques often use Gaussian beams for operations such as drilling and cutting. Due to the circular symmetry of the Gaussian beam's lateral spot, irregular cracks often form on both sides of the cutting path formed using the Gaussian beam. Since the cracks are uncontrollable, they can cause edge collapse in the brittle material during further fragmentation. In addition, the cross-section obtained by cutting with a Gaussian beam has a large taper, resulting in an uneven cross-section. Summary of the Invention

[0004] The purpose of the embodiments of the present invention is to provide a laser processing system and method for brittle materials, so as to solve the technical problem that the existing processing methods for brittle materials easily lead to chipping of cutting edges or uneven cross-sections.

[0005] In order to solve the above technical problems, an embodiment of the present invention provides a laser processing system for brittle materials, which adopts the following technical solutions:

[0006] The laser processing system for brittle materials comprises: a first processing component, the first processing component being used to form a modified area on a workpiece to be processed along a preset processing path;

[0007] Along the first direction, the first processing assembly includes a first laser and a phase modulation unit arranged in sequence; the first laser is used to emit a first light beam;

[0008] The phase modulation unit is used to modulate the first light beam emitted from the laser to obtain a modulated light beam with a long focal depth and an elliptical light spot, and the modulated light beam is used to be emitted to a workpiece to be processed so as to process the workpiece.

[0009] In some embodiments, the phase modulation unit includes a first phase modulation element and a second phase modulation element sequentially arranged along a first direction, and the first phase modulation element is arranged at a position between the first laser and the second phase modulation element;

[0010] The first phase modulation element is provided with an even number of phase regions all passing through the center of the first phase modulation element, and the phases of the phase regions are centrally symmetric along the central axis of the first phase modulation element; the first phase modulation element is used to phase modulate the first light beam emitted from the laser to obtain a modulated light beam with an elliptical light spot;

[0011] The second phase modulation element is a long focal depth optical element, and the long focal depth optical element is used to modulate the modulated light beam to obtain a modulated light beam with a long focal depth.

[0012] In some embodiments, in the phase regions of the first phase modulation element, adjacent phase regions have different phases, and separated phase regions have the same phase, and the phase difference between two adjacent phase regions is π.

[0013] In some embodiments, the first laser is an ultrashort pulse laser, and the wavelength of the emitted first light beam is 300nm-1100nm, the pulse width is less than 50ps, the single pulse energy is greater than 50μJ, and the pulse repetition frequency is 1KHz-300KHz.

[0014] In some embodiments, the laser processing system further includes a first beam expansion and collimation unit and a first focusing unit; along the first direction, the first laser, the first beam expansion and collimation unit, the phase modulation unit and the first focusing unit are arranged in sequence;

[0015] The first beam expansion and collimation unit is used to expand and collimate the first light beam emitted from the first laser to obtain a collimated first light beam, and the collimated first light beam is then emitted into the phase modulation unit;

[0016] The first focusing unit is used to focus the modulated light beam emitted from the phase modulation unit and then emit it toward the workpiece to be processed so as to process the workpiece.

[0017] In some embodiments, the laser processing system further includes a first stage and a first motion device; along a first direction, the first stage is arranged on a side of the phase modulation unit away from the first laser, the first stage is used to fix the workpiece to be processed, and the first motion device is used to drive the first stage to move and rotate in a three-dimensional plane.

[0018] In some embodiments, the laser processing system further includes a second processing component, the second processing component being configured to further process the modified region along a preset processing path to increase the width of the modified region;

[0019] The second processing assembly comprises a second laser arranged along a second direction, a second beam expanding and collimating unit, a beam scanning unit and a second focusing unit; a second light beam emitted by the second laser passes through the second beam expanding and collimating unit, the beam scanning unit and the second focusing unit in sequence and is then emitted to a workpiece to be processed;

[0020] The second beam expanding and collimating unit is configured to expand and collimate the second light beam emitted by the second laser to obtain a collimated second light beam;

[0021] The beam scanning unit is configured to control the second light beam emitted by the second beam expanding and collimating unit to move along the preset processing path;

[0022] The second focusing unit is configured to focus the second light beam emitted by the beam scanning unit and then emit the second light beam to the workpiece to be processed to process the workpiece.

[0023] In some embodiments, the second laser is a CO2 laser, and the second light beam emitted by the second laser has a wavelength of 10.6 μm.

[0024] In some embodiments, the laser processing system further comprises a second object table and a second moving device; along the second direction, the second object table is arranged on a side of the second focusing unit away from the beam scanning unit, the second object table is configured to fix the workpiece to be processed, and the second moving device is configured to move and rotate the second object table in a three-dimensional plane.

[0025] To solve the above technical problems, the embodiments of the present application further provide a laser processing method for brittle materials, which adopts the technical scheme as follows: the laser processing method for brittle materials is based on the laser processing system for brittle materials described above, and the laser processing method comprises the following steps:

[0026] The first laser emits a first light beam;

[0027] The first light beam is emitted into the phase modulation unit to be modulated to obtain a modulated light beam having long focal depth and an elliptical spot;

[0028] Along a preset processing path, the modulated light beam is emitted to a workpiece to be processed to process the workpiece to form a modified region.

[0029] Compared with the prior art, the laser processing system for brittle materials and the processing method provided by the embodiments of the present application have the following beneficial effects:

[0030] The laser processing system for brittle materials modulates a first light beam generated by a first laser through a phase modulation unit to obtain a modulated light beam, so that the modulated light beam can form an elliptical light spot with a long focal depth. When the modulated light beam is irradiated on a workpiece to be processed, an elliptical light spot with a long focal depth is formed. On the one hand, cracks on the workpiece to be processed are more likely to extend along the long axis direction of the elliptical light spot, reducing the probability of edge chipping. On the other hand, the long focal depth characteristic of the modulated light beam in the light propagation direction can improve the cross-sectional uniformity and flatness of the workpiece to be processed, and can improve processing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] To more clearly illustrate the solutions of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort. Among them:

[0032] Figure 1 1 is a schematic structural diagram of a laser processing system for brittle materials according to an embodiment of the present invention;

[0033] Figure 2 yes Figure 1 The longitudinal spot effect diagram of the modulated beam;

[0034] Figure 3 yes Figure 2 Energy distribution diagram of the longitudinal focal depth of the modulated beam;

[0035] Figure 4 yes Figure 1 The lateral spot effect diagram of the modulated beam;

[0036] Figure 5 It is adopted Figure 1 A cutting effect diagram obtained by the first processing component cutting the workpiece to be processed;

[0037] Figure 6 yes Figure 1 Phase distribution diagram of a first modulation element of a laser processing system for moderately brittle materials;

[0038] Figure 7 1 is a schematic flow chart of a laser processing method for brittle materials according to an embodiment of the present invention;

[0039] Figure 8 It is a schematic flow chart of a laser processing method for brittle materials in another embodiment of the present invention.

[0040] The reference numerals in the accompanying drawings are as follows:

[0041] 100. Laser processing system; 200. Workpiece to be processed;

[0042] 1. first processing assembly; 11. first laser; 12. phase modulation unit; 121. first phase modulation element; 122. second phase modulation element; 13. first beam expanding and collimating unit; 14. first focusing unit; 15. first stage; 16. first beam deflection unit; 2. second processing assembly; 21. second laser; 22. second beam expanding and collimating unit; 23. beam scanning unit; 24. second focusing unit; 25. second stage. DETAILED DESCRIPTION

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting of the application, for example, the terms "length", "width", "upper", "lower", "left", "right", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, refer to orientation or position as shown in the drawings and are used for convenience in describing the present application and are not intended to be limiting. The terminology includes the above-listed terms, derivatives thereof, and words of similar import.

[0044] The terms "include", "has", "having" or any variation thereof, in the present specification and claims, and the above description of the drawings, are intended to cover a non-exclusive inclusion; the terms "first", "second", and the like, in the present specification and claims, and the above description of the drawings, are used to distinguish different objects, not to describe a particular order. In the present specification and claims, and the above description of the drawings, when an element is referred to as being "fixed to" or "mounted to" or "connected to" or "coupled to" another element, it can be directly or indirectly connected to the other element. For example, when an element is referred to as being "connected to" another element, it can be directly or indirectly connected to the other element.

[0045] In addition, the reference herein to "embodiment" means that the specific features, structures, or characteristics described in connection with the embodiment can be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily all refer to the same embodiment, nor is it necessarily independent or alternative to other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0046] It should be noted that the laser processing system 100 of the embodiment of the present invention is primarily used for processing workpieces 200 made of brittle materials. Such workpieces 200 include products made of sapphire, zirconia, glass, and other materials. Specifically, the laser processing system 100 can be used to perform operations such as cutting and drilling holes on the brittle workpieces 200. Of course, the laser processing system 100 can also be used for processing other materials. Furthermore, the laser processing system 100 of the embodiment of the present invention can be a laser cutting device, a laser milling device, a laser engraving device, or other processing device. For ease of description, the following description focuses on cutting processing.

[0047] The embodiment of the present invention provides a laser processing system 100 for brittle materials, such as Figure 1 As shown, the laser processing system 100 includes a first processing component 1, which is used to form a modified area along a preset processing path on a workpiece 200 to be processed. Specifically in this embodiment, the first processing component 1 is used to cut the workpiece 200 to be processed, such as sapphire, to form cutting paths.

[0048] like Figure 1 As shown, along the first direction, the first processing component 1 includes a first laser 11 and a phase modulation unit 12 arranged in sequence; it should be noted that, in this embodiment, there is no special restriction on the specific path of the first direction, so that the light beam transmitted along the first direction can reach the preset cutting position of the workpiece 200 to be processed.

[0049] The first laser 11 is used to emit a first light beam; the phase modulation unit 12 is used to modulate the first light beam emitted from the first laser 11 to obtain a modulated light beam having a long focal depth and an elliptical light spot. The modulated light beam is used to be emitted toward the workpiece 200 to be processed to process the workpiece 200. It should be noted that in this embodiment, the modulated light beam with an elliptical light spot is formed by phase modulating the first light beam, wherein the modulated light beam obtained by modulation forms an even number of phases along its radial cross-section, all of which pass through the center of the modulated light beam and are symmetrical along the centerline of the modulated light beam.

[0050] It can be understood that the working principle of the laser processing system 100 for brittle materials is as follows: when a workpiece 200 of brittle material needs to be processed, such as cutting, for example, when cutting a glass plate, the glass plate is placed at a preset processing position, and a first light beam is emitted by the first laser 11. The first light beam is incident on the phase modulation unit 12 for modulation to obtain a modulated light beam with a long focal depth and an elliptical light spot; along the preset processing path, the modulated light beam is emitted toward the workpiece 200 to be processed to cut the workpiece 200 to form a cutting path. Specifically in this embodiment, as Figure 5As shown, when a 1mm thick glass plate is cut, the first laser 11 emits a first light beam, which enters the phase modulation unit 12 for modulation to obtain a modulated light beam with a long focal depth and an elliptical light spot. The modulated light beam can form multiple penetration points on the 1mm thick glass, and the distance between two adjacent penetration points is equal, so that the glass will crack along the preset processing path direction to form a cutting path.

[0051] In summary, compared with the existing technology, the laser processing system 100 for brittle materials has at least the following beneficial effects: the laser processing system 100 for brittle materials modulates the first light beam generated by the first laser 11 through the phase modulation unit 12 to obtain a modulated light beam, so that the modulated light beam can form an elliptical light spot and has the characteristic of a long focal depth. When the modulated light beam is irradiated on the workpiece 200 to be processed, an elliptical light spot with a long focal depth can be formed. On the one hand, the cracks on the workpiece 200 to be processed are more easily extended along the long axis direction of the elliptical light spot, reducing the probability of edge chipping. On the other hand, the long focal depth characteristic of the modulated light beam in the direction of light propagation can improve the cross-sectional uniformity and flatness of the workpiece 200 to be processed, and can improve the processing efficiency.

[0052] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0053] In some embodiments, as Figure 1 As shown, the phase modulation unit 12 includes a first phase modulation element 121 and a second phase modulation element 122 sequentially arranged along a first direction, and the first phase modulation element 121 is arranged between the first laser 11 and the second phase modulation element 122 .

[0054] like Figure 6As shown, the first phase modulation element 121 is provided with an even number of phase regions all passing through the center of the first phase modulation element 121, and the phases of the phase regions are centrally symmetric along the central axis of the first phase modulation element 121; the first phase modulation element 121 is used to phase-modulate the first light beam emitted from the first laser 11 to obtain a modulated light beam with an elliptical light spot; specifically, the first phase modulation element 121 can be a spatial light modulator or a diffraction optical element, etc., any element that can phase modulate the first light beam, and no special limitation is imposed here. It can be understood that by injecting the first light beam emitted by the first laser 11 into different phase regions of the first phase modulation element 121 for phase modulation, the first phase modulation element 121 destroys the circular symmetry of the lateral phase of the first light beam emitted from the first laser 11. It should be noted that the lateral phase in this embodiment refers to the phase of the radial cross-section of the first light beam, so that the first light beam is modulated to form an even number of modulated light beams along the radial cross-section direction of its own light beam, all of which pass through the center line of the modulated light beam and are centrally symmetric along the center line of the modulated light beam, so that the modulated light beam forms an ellipse. Even if the first light beam with a circular spot emitted from the first laser 11 is modulated by the first phase modulation element 121 to form a modulated light beam with an elliptical spot, the cracks formed by the modulated light beam with the elliptical spot in cutting the workpiece 200 to be processed can be more easily extended along the long axis direction of the elliptical spot, thereby reducing the probability of edge collapse.

[0055] The second phase modulation element 122 is a long-focus optical element, which is used to modulate the modulated light beam to obtain a modulated light beam with a long focal depth. It is understood that the long-focus optical element can be an optical element capable of producing a long-focus light beam, such as an axicon, and is not particularly limited herein. It should be noted that in this embodiment, the long-focus modulated light beam has a focal depth of up to 2 mm, capable of penetrating a workpiece 200 to be processed with a thickness of less than 2 mm. It is understood that further modulation of the modulated light beam modulated by the first phase modulation element 121 by the long-focus optical element can produce a modulated light beam with a long focal depth, i.e., can form an elliptical light spot with a long focal depth. The long focal depth characteristic of the laser in the direction of light propagation can further improve the cross-sectional uniformity and flatness of the workpiece 200 to be processed, and further improve processing efficiency. It should be noted that, in other embodiments, the first phase modulation element 121 and the second phase modulation element 122 can be combined into one optical element for replacement, wherein the optical element can both phase modulate the first light beam and modulate the first light beam into a light beam with a long focal depth performance.

[0056] In some embodiments, in the phase region of the first phase modulation element 121, the phases of adjacent phase regions are different, the phases of separated phase regions are the same, and the phase difference between two adjacent phase regions is π. It can be understood that the first light beam emitted by the first laser 11 is modulated by the first phase modulation element 121, and the first light beam can be modulated into an even number of modulated light beams that all pass through the center line of the modulated light beam and are symmetrical along the center line of the modulated light beam, and the adjacent phases of the modulated light beams differ by π, and the separated phases are the same. Figures 2 to 4 As shown, a modulated light beam can be formed that is filamentous along the propagation direction of the light beam, with a very small central spot and an elliptical spot shape. When cutting the workpiece 200 to be processed, an extremely narrow cutting path can be formed, which can further effectively reduce the risk of edge collapse. In a specific embodiment, as Figure 6 As shown, twelve phase regions are formed in the first phase modulation element 121, wherein the phase difference between two adjacent phase regions is π, and the phases of the separated phase regions are the same, wherein the angle of the phase region α in the figure is less than 10°.

[0057] In some embodiments, the first laser 11 is an ultrashort pulse laser, and the first light beam emitted is a Gaussian beam. Before entering the phase modulation unit 12, the Gaussian beam is a laser beam with a circular spot distribution; the wavelength of the first light beam is 300nm~1100nm, the pulse width is less than 50ps, the single pulse energy is greater than 50μJ, and the pulse repetition frequency is 1KHz~300KHz.

[0058] In some embodiments, as Figure 1 As shown, the laser processing system 100 further includes a first beam expansion and collimation unit 13 and a first focusing unit 14; along the first direction, the first laser 11, the first beam expansion and collimation unit 13, the phase modulation unit 12 and the first focusing unit 14 are arranged in sequence. The first beam expansion and collimation unit 13 is used to expand and collimate the first light beam emitted from the first laser 11 to obtain a collimated first light beam, and the collimated first light beam is then emitted into the phase modulation unit 12. The first focusing unit 14 is used to focus the modulated light beam emitted from the phase modulation unit 12 to form a focused light spot, which is emitted toward the workpiece 200 to be processed so as to perform high-precision processing on the workpiece 200 to be processed; it should be noted that the first focusing unit 14 can be a single lens or a combined lens system as long as it can focus the modulated light beam, and there is no special limitation here. It can be understood that the first light beam emitted by the first laser 11 passes through the first beam expansion and collimation unit 13, the phase modulation unit 12 and the first focusing unit 14 in sequence to form a focused modulated light beam. The spot size of the modulated light beam can reach 2 to 4 μm, and the focal depth can reach 2 mm, which can penetrate the workpiece 200 to be processed with a thickness of less than 2 mm.

[0059] In some embodiments, as Figure 1 As shown, the first processing component 1 may further include a first beam deflection unit 16, which is used to change the transmission direction of the first light beam according to the actual optical path space structure, and can be placed between any two adjacent elements of the first laser 11, the first beam expansion and collimation unit 13, the phase modulation unit 12, and the first focusing unit 14. Specifically, in this embodiment, the first beam deflection unit 16 is arranged between the first laser 11 and the first beam expansion and collimation unit 13, and the first beam deflection unit 16 is at a 45° angle to the incident light of the first beam. The first light beam emitted by the first laser 11 and propagating in the horizontal direction is turned 90° toward the first beam expansion and collimation unit 13, thereby improving the compactness of the structure.

[0060] In some embodiments, as Figure 1 As shown, the laser processing system 100 also includes a second processing component 2, which is used to further process the modified area along a preset processing path to increase the width of the modified area. It should be noted that the width of the modified area refers to the direction of intersection along the preset processing path, such as further widening the width of the cutting path through the second processing component 2.

[0061] Specifically, the second processing assembly 2 comprises a second laser 21, a second beam expanding and collimating unit 22, a beam scanning unit 23 and a second focusing unit 24 arranged along a second direction; the second laser 21 emits a second light beam which sequentially passes through the second beam expanding and collimating unit 22, the beam scanning unit 23 and the second focusing unit 24 and then is directed to the workpiece 200 to be processed; the second beam expanding and collimating unit 22 is configured to expand and collimate the second light beam emitted from the second laser 21 to obtain a collimated second light beam; the beam scanning unit 23 is configured to control the second light beam emitted from the second beam expanding and collimating unit 22 to move along a preset processing path, and it is to be noted that in the embodiment, the beam scanning unit 23 can be a galvanometer scanning system, by which the second light beam can be controlled to move along the preset processing path and to move along a direction intersecting with the preset processing path to further widen the cutting path, and of course, in other embodiments, the beam scanning unit 23 is not limited to the galvanometer scanning system; the second focusing unit 24 is configured to focus the second light beam emitted from the beam scanning unit 23 and then direct the second light beam to the workpiece 200 to be processed to process the workpiece 200 to be processed. It can be understood that the further scanning of the modified region such as the cutting path processed by the first processing assembly 1 by the second light beam along the preset processing path separates the material to be removed from the material to be retained on the workpiece 200 to be processed, so that the width of the cutting path is further widened; it is to be noted that in the embodiment, after being processed by the first processing assembly 1, the material to be removed on the workpiece 200 to be processed is not completely separated from the material to be retained, and further processing by the second processing assembly 2 is needed to separate the material to be removed from the material to be retained on the workpiece.

[0062] In some embodiments, the laser processing system 100 further comprises a visual detection assembly (not shown in the figure) configured to identify the modified region formed on the workpiece 200 to be processed after being processed by the first processing assembly 1, so that the processing path of the modified region on the workpiece 200 to be processed coincides with the scanning path of the second light beam, thereby improving the processing accuracy.

[0063] In some embodiments, the second laser 21 is a CO2 laser, and the second light beam emitted by the second laser 21 is a Gaussian light beam with a wavelength of 10.6 μm; the Gaussian light beam is used to further scan and process the modified region such as the cutting path processed by the first processing assembly 1, so as to further widen the width of the cutting path and to separate the material to be removed from the material to be retained, and the surface integrity of the material to be retained is not affected.

[0064] In some embodiments, the second processing component 2 may further include a second beam deflection unit (not shown), which is used to change the transmission direction of the second light beam according to the actual optical path spatial structure, and can be placed between any two adjacent elements of the second laser 21, the second beam expansion and collimation unit 22, the beam scanning unit 23, and the second focusing unit 24.

[0065] In some embodiments, as Figure 1 As shown, the laser processing system 100 also includes a first stage 15 and a first motion device (not shown); along the first direction, the first stage 15 is arranged on the side of the phase modulation unit 12 away from the first laser 11, the first stage 15 is used to fix the workpiece 200 to be processed, and the first motion device is used to drive the first stage 15 to move and rotate in a three-dimensional plane. Specifically in this embodiment, the first motion device is used to drive the first stage 15 to rotate around the central axis of the first stage 15 itself. It is understandable that when laser cutting is required on the workpiece 200 to be processed, the workpiece 200 to be processed is placed on the first stage 15, and the first motion device drives the first stage 15 to perform translational motion, so that the modulated light beam modulated by the phase modulation unit 12 is focused on the preset processing position of the workpiece 200 to be processed. Then, the first motion device drives the first stage 15 to further rotate, so that the long axis direction of the elliptical spot of the modulated light beam coincides with the preset processing path, so that cracks formed in the workpiece 200 to be processed during the cutting process are more likely to extend along the long axis direction of the elliptical spot, thereby reducing the probability of edge chipping. Of course, in other embodiments, the first motion device can only drive the first stage 15 to perform translational motion, in which case the phase modulation unit 12 is fixed to an external rotation drive device, which can drive the phase modulation unit 12 to rotate, so that the long axis direction of the elliptical spot of the modulated light beam coincides with the preset processing path.

[0066] In some embodiments, as Figure 1 As shown, the laser processing system 100 also includes a second stage 25 and a second motion device (not shown). Along the second direction, the second stage 25 is positioned on a side of the second focusing unit 24 away from the beam scanning unit 23. The second stage 25 is used to secure the workpiece 200 to be processed, and the second motion device is used to drive the second stage 25 to move and rotate within a three-dimensional plane. It is understood that after the workpiece 200 is processed by the first processing assembly 1 to obtain a modified area, the workpiece 200 is placed on the second stage 25. The second motion device drives the second stage 25 to perform translational or rotational motion, so that the second beam is focused on the modified area of ​​the workpiece 200.

[0067] In some embodiments, vacuum adsorption holes may be provided on both the first stage 15 and the second stage 25, and the vacuum adsorption holes are used to adsorb the workpiece 200 to be processed. It is understood that by providing vacuum adsorption holes on the respective stages of the first stage 15 and the second stage 25, the vacuum adsorption holes are connected to an external vacuum generating device to adsorb and position the workpiece 200 to be processed placed on the stages, thereby fixing the workpiece 200 to be processed.

[0068] In some embodiments, the laser processing system 100 further includes a gripping device (not shown) for gripping and loading the workpiece 200. Specifically, in this embodiment, the gripping device can be used to grip the workpiece 200 and move it to the first loading platform 15 or the second loading platform 25.

[0069] Based on the above-mentioned laser processing system 100 for brittle materials, an embodiment of the present invention further provides a laser processing method for brittle materials, wherein the laser processing method for brittle materials is based on the above-mentioned laser processing system 100 for brittle materials, such as Figure 7 As shown, the laser processing method includes the following steps:

[0070] S110. The first laser 11 emits a first light beam;

[0071] S120. The first light beam is incident on the phase modulation unit 12 for modulation to obtain a modulated light beam having a long focal depth and an elliptical spot;

[0072] S130 . Along a preset processing path, the modulated light beam is emitted toward the workpiece 200 to be processed so as to process the workpiece 200 to form a modified area.

[0073] It should be noted that, in step S110, after the first laser 11 emits the first light beam, the following steps may also be included: the emitted first light beam is injected into the first beam expansion and collimation unit 13 to obtain a collimated first light beam, and the collimated first light beam is then injected into the phase modulation unit 12 for modulation; in addition, in step S120, after the first light beam is injected into the phase modulation unit 12 for modulation to obtain a modulated light beam with a long focal depth and an elliptical light spot, the following steps may also be included: the first light beam emitted from the phase modulation unit 12 is injected into the first focusing unit 14 to obtain a focused first light beam, and the focused first light beam is then injected toward the workpiece 200 to be processed.

[0074] In summary, compared with the existing technology, the laser processing method of brittle materials has at least the following beneficial effects: the laser processing method of brittle materials adopts the above-mentioned laser processing system 100 for brittle materials, and modulates the first light beam generated by the first laser 11 through the phase modulation unit 12 to obtain a modulated light beam, so that the modulated light beam can form an elliptical light spot and has the characteristic of a long focal depth. When the modulated light beam is irradiated on the workpiece 200 to be processed, it can form an elliptical light spot with a long focal depth. On the one hand, it makes it easier for cracks on the workpiece 200 to be processed to extend along the long axis direction of the elliptical light spot, reducing the probability of edge chipping. On the other hand, the long focal depth characteristic of the laser in the direction of light propagation can improve the uniformity and flatness of the cross section, and can improve the processing efficiency.

[0075] In some embodiments, after the step of irradiating the workpiece 200 along a preset processing path with a modulated light beam to process the workpiece 200 to form a modified area, Figure 8 As shown, the following steps are also included:

[0076] S210. The second laser 21 emits a second light beam, and the emitted second light beam enters the second beam expansion and collimation unit 22 to obtain a collimated second light beam;

[0077] S220. The collimated second light beam is incident on the light beam scanning unit 23 so that the second light beam moves along the first processing track direction;

[0078] S230. The second light beam emitted from the beam scanning unit 23 is incident on the second focusing unit 24 to obtain a focused second light beam;

[0079] S240. Along the preset processing path, the second light beam is emitted toward the workpiece 200 to be processed to further process the modified area to increase the width of the modified area.

[0080] It can be understood that the second light beam is used to further scan the modified area such as the cutting path obtained by the first processing component 1 along the preset processing path, so as to separate the material to be removed and the material to be retained on the workpiece 200 to be processed, so that the width of the cutting path is further widened.

[0081] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be included within the scope of the claims of the present invention.

Claims

1. A laser processing system for brittle materials, characterized in that: The laser processing system includes a first processing component, which is used to form a modified area on a workpiece to be processed along a preset processing path; Along the first direction, the first processing assembly includes a first laser and a phase modulation unit arranged in sequence; the first laser is used to emit a first light beam; The phase modulation unit is used to modulate the first light beam emitted from the first laser to obtain a modulated light beam with a long focal depth and an elliptical light spot, and the modulated light beam is used to be emitted to a workpiece to be processed so as to process the workpiece; The phase modulation unit includes a first phase modulation element and a second phase modulation element sequentially arranged along a first direction, and the first phase modulation element is arranged at a position between the first laser and the second phase modulation element; The first phase modulation element is provided with an even number of phase regions all passing through the center of the first phase modulation element, and the phases of the phase regions are centrally symmetric along the central axis of the first phase modulation element; the first phase modulation element is used to phase modulate the first light beam emitted from the first laser to obtain a modulated light beam with an elliptical light spot; The second phase modulation element is a long focal depth optical element, and the long focal depth optical element is used to modulate the modulated light beam to obtain a modulated light beam with a long focal depth.

2. The laser processing system for brittle materials according to claim 1, characterized in that: In the phase regions of the first phase modulation element, adjacent phase regions have different phases, and separated phase regions have the same phase. The phase difference between two adjacent phase regions is π.

3. The laser processing system for brittle materials according to claim 1, characterized in that: The first laser is an ultrashort pulse laser, and the wavelength of the emitted first light beam is 300nm-1100nm, the pulse width is less than 50ps, the single pulse energy is greater than 50μJ, and the pulse repetition frequency is 1KHz-300KHz.

4. The laser processing system for brittle materials according to claim 1, characterized in that: The laser processing system further includes a first beam expansion and collimation unit and a first focusing unit; along the first direction, the first laser, the first beam expansion and collimation unit, the phase modulation unit and the first focusing unit are arranged in sequence; The first beam expansion and collimation unit is used to expand and collimate the first light beam emitted from the first laser to obtain a collimated first light beam, and the collimated first light beam is then emitted into the phase modulation unit; The first focusing unit is used to focus the modulated light beam emitted from the phase modulation unit and then emit it toward the workpiece to be processed so as to process the workpiece.

5. The laser processing system for brittle materials according to claim 1, characterized in that: The laser processing system also includes a first stage and a first motion device; along the first direction, the first stage is arranged on the side of the phase modulation unit away from the first laser, the first stage is used to fix the workpiece to be processed, and the first motion device is used to drive the first stage to move and rotate in a three-dimensional plane.

6. The laser processing system for brittle materials according to any one of claims 1 to 5, characterized in that: The laser processing system further includes a second processing component, which is used to further process the modified area along a preset processing path to increase the width of the modified area; The second processing assembly includes a second laser, a second beam expansion and collimation unit, a beam scanning unit, and a second focusing unit arranged along a second direction; the second beam emitted by the second laser passes through the second beam expansion and collimation unit, the beam scanning unit, and the second focusing unit in sequence and then is emitted to the workpiece to be processed; The second beam expansion and collimation unit is used to expand and collimate the second light beam emitted from the second laser to obtain a collimated second light beam; The beam scanning unit is used to control the second light beam emitted from the second beam expansion and collimation unit so that the second light beam moves along the preset processing path; The second focusing unit is used to focus the second light beam emitted from the light beam scanning unit and then emit it toward the workpiece to be processed so as to process the workpiece.

7. The laser processing system for brittle materials according to claim 6, characterized in that: The second laser is a CO2 laser, and the wavelength of the second light beam emitted is 10.6 μm.

8. The laser processing system for brittle materials according to claim 6, characterized in that: The laser processing system also includes a second stage and a second motion device; along the second direction, the second stage is arranged on the side of the second focusing unit away from the beam scanning unit, the second stage is used to fix the workpiece to be processed, and the second motion device is used to drive the second stage to move and rotate in a three-dimensional plane.

9. A laser processing method for brittle materials, characterized in that: The laser processing method is based on the laser processing system for brittle materials according to any one of claims 1 to 8; the laser processing method comprises the following steps: The first laser emits a first light beam; The first light beam is incident on the phase modulation unit for modulation to obtain a modulated light beam with a long focal depth and an elliptical light spot; Along a preset processing path, the modulated light beam is emitted toward the workpiece to be processed to process the workpiece to form a modified area.

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