阅读说明：本技术 一种双激光复合隐形切割方法及加工系统 (Double-laser composite invisible cutting method and processing system ) 是由 谢小柱 张祖铖 龙江游 任庆磊 胡伟 赖庆 黄亚军 于 2021-08-04 设计创作，主要内容包括：本发明提供了一种双激光复合隐形切割方法,具体包括如下步骤：S1选取连续激光器和脉冲激光器,通过控制系统控制用于放置待加工工件的运动加工平台能运动至加工位置；S2打开连续激光器,保持连续激光器连续发出激光,对待加工工件进行预改质,形成预改质区；S3打开脉冲激光器,脉冲激光器输出特定频率的激光在预改质区内沿预定切割路径进行二次改质,形成二次改质区,关闭激光器,完成工件的隐形切割。本发明还提供一种双激光复合隐形切割方法所用的加工系统。本发明解决现有的双激光隐形切割技术需严格控制两个脉冲激光之间的时序,操作难度大的问题。本发明大幅度降低实用难度,提高了切割效果和产品优良率。(The invention provides a double-laser composite invisible cutting method, which specifically comprises the following steps: s1, selecting a continuous laser and a pulse laser, and controlling a motion processing platform for placing a workpiece to be processed to move to a processing position through a control system; s2, opening the continuous laser, keeping the continuous laser to continuously emit laser, and pre-modifying the workpiece to be processed to form a pre-modified region; and S3, turning on the pulse laser, outputting laser with specific frequency by the pulse laser to carry out secondary modification in the pre-modification region along a preset cutting path to form a secondary modification region, turning off the laser, and finishing the invisible cutting of the workpiece. The invention also provides a processing system used by the double-laser composite invisible cutting method. The invention solves the problems that the existing double-laser invisible cutting technology needs to strictly control the time sequence between two pulse lasers and has high operation difficulty. The invention greatly reduces the practical difficulty and improves the cutting effect and the product yield.)

1. A double-laser composite invisible cutting method is characterized by comprising the following steps:

s1: selecting a continuous laser (1) and a pulse laser (2), controlling a motion processing platform (11) for placing a workpiece (10) to be processed to move to a processing position through a control system, and controlling a laser beam emitted by the continuous laser (1) to be focused to an initial cutting position of the workpiece (10) to be processed through a first light path and a laser beam emitted by the pulse laser (2) to be focused to the initial cutting position of the workpiece (10) to be processed through a second light path through the control system;

s2: opening the continuous laser (1), controlling the motion processing platform (11) to move according to a set processing path by the control system, keeping the continuous laser (1) continuously emitting laser, and performing pre-modification on a workpiece (10) to be processed to form a pre-modification region;

s3: and (3) opening the pulse laser (2), outputting laser with a specific frequency by the pulse laser (2), performing secondary modification in the pre-modified region along a preset cutting path to form a secondary modified region, and closing the continuous laser (1) and the pulse laser (2) after finishing the secondary modification of the preset cutting path to finish the invisible cutting of the workpiece.

2. The dual-laser composite stealth dicing method according to claim 1, wherein the workpiece subjected to stealth dicing is subjected to an external force along a dicing path to perform dicing along the dicing path.

3. The double-laser composite stealth dicing method according to claim 1, characterized in that the laser wavelength of the continuous laser (1) is between a weak absorption band and an absorption band of the workpiece to be processed (10).

4. The double-laser composite stealth dicing method according to claim 1, wherein a laser pulse width of the pulse laser (2) is any one of nanosecond, picosecond, and femtosecond levels.

5. The double-laser composite invisible cutting method according to claim 1, characterized in that the workpiece (10) to be processed is any one of transparent materials such as Si, SiC, GaAs-GaP, GaAsP, GaAsAl, glass, InSb, Ge, AlN, GaN, ZnO, Ge-Si, diamond, sapphire, and the like.

6. The dual-laser composite invisible cutting method as claimed in claim 2, characterized in that a splitting machine is used for splitting the workpiece which is subjected to the invisible cutting along the cutting path direction, so that the workpiece which is subjected to the invisible cutting is split along the cutting path.

7. A processing system used in a double-laser composite invisible cutting method is characterized by comprising a control system, a motion processing platform (11) which is used for placing a workpiece (10) to be processed and can move according to a set processing path, a continuous laser (1) which is used for emitting continuous laser beams, a pulse laser (2) which is used for emitting pulse laser beams, a first light path which can focus the continuous laser beams emitted by the continuous laser (1) on the workpiece (10) to be processed and can carry out pre-modification on the workpiece (10) to be processed to form a pre-modification area, a second light path which can focus the pulse laser beams emitted by the pulse laser (2) on the workpiece (10) to be processed and can carry out secondary modification on the pre-modification area to form a secondary modification area, the continuous laser (1), the pulse laser (2) and the motion processing platform (11) are all electrically connected with a control system.

8. The processing system for the double-laser composite invisible cutting method according to claim 7, further comprising a focusing system for focusing the laser beams of the continuous laser (1) and the pulse laser (2) to an initial cutting position, wherein the focusing system is electrically connected with the control system.

9. The processing system used in the double-laser composite invisible cutting method according to claim 8, wherein the first optical path comprises a first beam expander (3), a first beam splitter (6) and a first focusing high power objective lens (9) which are sequentially arranged, a laser beam emitted by the continuous laser (1) is expanded by the first beam expander (3), the beam is converted into a vertical direction by the first beam splitter (6), and a laser beam spot is focused into a workpiece to be processed by the first focusing high power objective lens (9); the second light path comprises a second beam expander (4), a second beam splitter (7) and a first focusing high-power objective lens (9) which are sequentially arranged, laser emitted by the pulse laser (2) is expanded through the second beam expander (4), the light beam is converted into a vertical direction through the second beam splitter (7), and laser beam spots are focused into a workpiece to be processed through the first focusing high-power objective lens (9); the focusing system is a CCD focusing system, the CCD focusing system comprises a CCD light source (13) and a CCD camera (12), a light beam emitted by the CCD light source (13) reaches the surface of a workpiece (10) to be processed and is reflected to enter a third light path of the CCD camera (12) for imaging, the third light path comprises a first focusing high-power objective lens (9) and a third spectroscope (8), after the light beam emitted by the CCD light source (13) is focused to the surface of the workpiece (10) to be processed through the first focusing high-power objective lens (9), the reflected light beam reversely passes through the first focusing high-power objective lens (9) and enters the CCD camera (12) for imaging through the third spectroscope (8) in the direction changing manner.

10. The processing system used in the double-laser composite invisible cutting method according to claim 8, wherein the first optical path comprises a first beam expander (3), a first beam splitter (6) and a first focusing high power objective lens (9) which are sequentially arranged, a laser beam emitted by the continuous laser (1) is expanded by the first beam expander (3), the beam is converted into a vertical direction by the first beam splitter (6), and a laser beam spot is focused into a workpiece to be processed by the first focusing high power objective lens (9); the second light path comprises a second beam expander (4), a second beam splitter (7) and a second focusing high-power objective lens (91) which are sequentially arranged, laser emitted by the pulse laser (2) is expanded through the second beam expander (4), the light beam is converted into a vertical direction through the second beam splitter (7), and laser beam spots are focused into a workpiece to be processed through the second focusing high-power objective lens (91);

the focusing system comprises a first CCD focusing system and a second CCD focusing system, the first CCD focusing system comprises a CCD light source (13) and a CCD camera (12), light beams emitted by the CCD light source (13) reach the surface of a workpiece (10) to be processed and are reflected to enter a third light path of the CCD camera (12) for imaging, the third light path comprises a first focusing high-power objective lens (9) and a third beam splitter (8), after the light beams emitted by the CCD light source (13) are focused to the surface of the workpiece (10) to be processed through the first focusing high-power objective lens (9), the reflected light beams reversely pass through the first focusing high-power objective lens (9) and enter the CCD camera (12) for imaging through the third beam splitter (8) in the direction changing manner; the second CCD focusing system comprises a second CCD light source (131) and a second CCD camera (121), a fourth light path which enables light beams emitted by the second CCD light source (131) to reach the surface of a workpiece (10) to be processed and is reflected to enter the second CCD camera (121) for imaging is arranged, the fourth light path comprises a second focusing high-power objective lens (91) and a fourth spectroscope (81), after the light beams emitted by the second CCD light source (131) are focused to the surface of the workpiece (10) to be processed through the second focusing high-power objective lens (91), the reflected light beams reversely pass through the second focusing high-power objective lens (91) and enter the second CCD camera (121) for imaging through the fourth spectroscope (81) in a direction changing mode.

Technical Field

The invention relates to the technical field of laser cutting, in particular to a double-laser composite invisible cutting method and a processing system.

Background

In comparison with the development from sawing to laser cutting, which requires the advantages of non-contact, less damage to the wafer, and high efficiency, the laser cutting is favored and becomes one of the key technologies for cutting semiconductor. Many laser cutting is based on laser surface ablation to form stress grooves for splitting, and compared with mechanical cutting methods such as sawing, the method has obvious progress, and the method still has certain damage to the wafer, namely a large amount of slag exists on the cutting surface of laser 'hot cutting', and the edge breakage phenomenon exists during cutting. In order to solve the problem, the semiconductor industry provides a new processing method, namely a laser invisible cutting technology, namely invisible cutting is carried out in the wafer, and then splitting is carried out, so that the surface cannot be damaged.

The laser invisible cutting is used as a scheme for cutting the wafer by laser, so that the problem of the scribing of the grinding wheel can be avoided. The laser invisible cutting is to focus a single pulse of pulse laser inside a material through the surface of the material, and the energy density is higher in a focal region to form a multi-photon absorption nonlinear absorption effect, so that the material is modified to form a crack. Each laser pulse acts at equal intervals to form equal-interval damage, so that a modified layer can be formed in the material, the molecular bond of the material at the position of the modified layer is damaged, the connection of the material is fragile and easy to separate, the product is fully separated by stretching the carrier film after cutting, a gap is formed between the chip and the chip, and the damage caused by mechanical direct contact and pure water flushing is avoided by the processing mode. The laser stealth cutting is a high-temperature and high-pressure process for forming a modified layer inside, so that the process becomes mild and controllable, and the problem that the stealth cutting quality is improved still needs to be solved in the stealth cutting field at present. Chinese patent publication No. CN111069793A discloses a method for stealth cutting with a double-pulse laser, which respectively adopts a nanosecond long-pulse laser and an ultrafast pulse laser, preheats the long-pulse laser to form a modified layer, then performs stealth cutting with the ultrafast laser, and alternately emits laser through an electric control device, so that plasma generated by ablation of the short-pulse laser beam in a material, material vapor, and a melt can directionally expand along the direction of the modified layer generated by preheating the long-pulse laser beam, thereby realizing the controllability of the direction of a stealth cutting crack, reducing the damage area of the stealth cutting in the material, and greatly improving the processing quality.

However, in the above scheme, an electrical device is required to control the time sequence alternation of the two lasers, the secondary modification process of the pulse laser is difficult to control, and in the actual cutting process, the time sequence between the two pulse lasers needs to be strictly controlled to control the light emission, so that the processing difficulty is greatly improved.

Disclosure of Invention

The invention aims to solve the problems that the existing double-laser invisible cutting technology needs to strictly control the time sequence between two pulse lasers and has high operation difficulty, and provides a double-laser composite invisible cutting method and a processing system. The invention does not need to control the time sequence alternation, interference and other influences of the two lasers, greatly reduces the practical difficulty, and improves the effect after cutting and the excellent rate of products.

In order to solve the technical problems, the invention adopts the technical scheme that:

a double-laser composite invisible cutting method specifically comprises the following steps:

s1: selecting a continuous laser and a pulse laser, controlling a motion processing platform for placing a workpiece to be processed to move to a processing position through a control system, and controlling a laser beam emitted by the continuous laser to be focused to an initial cutting position of the workpiece to be processed through a first light path and a laser beam emitted by the pulse laser to be focused to the initial cutting position of the workpiece to be processed through a second light path through the control system;

s2: opening the continuous laser, controlling the motion processing platform to move according to a set processing path by the control system, keeping the continuous laser to continuously emit laser, and performing pre-modification on a workpiece to be processed to form a pre-modified region;

s3: and (3) opening the pulse laser, outputting laser with a specific frequency by the pulse laser to perform secondary modification in the pre-modification region along the preset cutting path to form a secondary modification region, and closing the continuous laser and the pulse laser after finishing the secondary modification of the preset cutting path to finish the invisible cutting of the workpiece.

In this way, a continuous laser and a pulse laser are selected to respectively emit a continuous laser beam and a pulse laser beam, the continuous laser is kept normally open, a pre-modification region is formed in the workpiece, the pulse laser performs secondary modification in the pre-modification region formed by the continuous laser, the process of the secondary modification of the pulse laser becomes milder and more controllable, the effect of the secondary modification of the pulse laser is improved, and the required energy of the pulse laser is greatly reduced; the continuous laser and the pulse laser do not work alternately but work, namely the pulse laser performs invisible cutting in the environment that the continuous laser irradiates, the positioning platform where the workpiece is located is moved in the cutting process, the whole workpiece can be cut, a series of cracks such as the shape of the invisible cutting crack, the length, the direction and the effect of the crack are controllable in forming related parameters through the pre-modification of a continuous laser spot and the ablation of the pulse laser, the actual operation difficulty is greatly reduced, and the effect of the invisible cutting after the crack is cut and the yield of products are improved.

Further, the workpiece which is subjected to the invisible cutting is subjected to external acting force along the cutting path, so that the workpiece is divided along the cutting path.

Further, the laser wavelength of the continuous laser is between the weak absorption band and the absorption band of the workpiece to be processed. Thus, the energy density of the continuous laser can be controlled below the material ablation threshold, so that the spot obtained by the continuous laser is larger, and a pre-modification region with larger depth and width is formed.

Further, the pulse width of the laser of the pulse laser is one of nanosecond, picosecond and femtosecond level. Therefore, the light spot of the continuous laser is larger than that of the pulse laser, so that the energy density of the continuous laser is smaller than that of the pulse laser, and the continuous laser is more moderate, so that the light spot obtained by the continuous laser is larger, a pre-modified region with larger depth and width can be formed, the invisible cutting process can be mild by combining with the secondary modification of the pulse laser, the unexpected and uncontrollable cracks caused by the conventional invisible cutting can be avoided, and the continuous laser can be greatly suitable for materials with different thicknesses.

Further, the workpiece to be processed includes, but is not limited to, one of transparent materials such as Si, SiC, GaAs-GaP, GaAsP, GaAsAl, glass, InSb, Ge, AlN, GaN, ZnO, Ge-Si, diamond, sapphire, etc.

Furthermore, a splitting machine can be used for splitting the cut workpiece according to the direction of the cutting path, so that the workpiece is separated along the cutting path.

A processing system used in a double-laser composite invisible cutting method comprises a control system, a motion processing platform used for placing a workpiece to be processed and moving according to a set processing path, a continuous laser used for emitting a continuous laser beam, a pulse laser used for emitting a pulse laser beam, a first light path used for focusing the continuous laser beam emitted by the continuous laser on the workpiece to be processed and pre-modifying the workpiece to be processed to form a pre-modified region, and a second light path used for focusing the pulse laser beam emitted by the pulse laser on the workpiece to be processed and performing secondary modification on the pre-modified region to form a secondary modified region, wherein the continuous laser, the pulse laser and the motion processing platform are electrically connected with the control system.

Further, the laser cutting machine also comprises a focusing system for focusing the laser beams of the continuous laser and the pulse laser at the initial cutting position, and the focusing system is electrically connected with the control system.

As a preferred scheme, the first optical path comprises a first beam expander, a first beam splitter and a first focusing high-power objective lens which are sequentially arranged, a laser beam emitted by the continuous laser is expanded by the first beam expander, the beam is converted into a vertical direction by the first beam splitter, and a laser beam spot is focused into a workpiece to be processed by the first focusing high-power objective lens; the second optical path comprises a second beam expander, a second beam splitter and a first focusing high-power objective lens which are sequentially arranged, laser emitted by the pulse laser is expanded by the second beam expander, the beam is converted into a vertical direction by the second beam splitter, and laser beam spots are focused into a workpiece to be processed by the first focusing high-power objective lens; the focusing system is a CCD focusing system, the CCD focusing system comprises a CCD light source and a CCD camera, and a third light path, light beams emitted by the CCD light source reach the surface of a workpiece to be processed and are reflected to enter the CCD camera) for imaging, the third light path comprises a first focusing high-power objective lens and a third beam splitter, after the light beams emitted by the CCD light source are focused to the surface of the workpiece to be processed through the first focusing high-power objective lens, the reflected light beams reversely pass through the first focusing high-power objective lens and enter the CCD camera for imaging through the direction change of the third beam splitter.

As another preferred scheme, the first optical path includes a first beam expander, a first beam splitter and a first focusing high power objective lens, which are sequentially arranged, the laser beam emitted by the continuous laser is expanded by the first beam expander, the beam is converted into a vertical direction by the first beam splitter, and the laser beam spot is focused into the workpiece to be processed by the first focusing high power objective lens; the second optical path comprises a second beam expander, a second beam splitter and a second focusing high-power objective lens which are sequentially arranged, laser emitted by the pulse laser is expanded by the second beam expander, the beam is converted into a vertical direction by the second beam splitter, and laser beam spots are focused into a workpiece to be processed by the second focusing high-power objective lens; the focusing system comprises a first CCD focusing system and a second CCD focusing system, the first CCD focusing system comprises a CCD light source and a CCD camera, light beams emitted by the CCD light source are transmitted to the surface of a workpiece to be processed and reflected to enter a third light path for imaging of the CCD camera, the third light path comprises a first focusing high-power objective lens and a third beam splitter, after the light beams emitted by the CCD light source are focused to the surface of the workpiece to be processed through the first focusing high-power objective lens, the reflected light beams reversely pass through the first focusing high-power objective lens and enter the CCD camera for imaging through the direction change of the third beam splitter; the second CCD focusing system comprises a second CCD light source and a second CCD camera, a light beam emitted by the second CCD light source is transmitted to the surface of a workpiece to be processed and reflected to enter a fourth light path of the second CCD camera for imaging, the fourth light path comprises a second focusing high-power objective lens and a fourth light splitting mirror, after the light beam emitted by the second CCD light source is focused to the surface of the workpiece to be processed through the second focusing high-power objective lens, the reflected light beam reversely penetrates through the second focusing high-power objective lens and enters the second CCD camera for imaging through the direction change of the fourth light splitting mirror.

It should be noted that the focusing principle of the focusing system is as follows: the laser beam of the CCD light source reaches the surface of a workpiece to be processed, is reflected by the beam splitter after being radiated by the surface of the workpiece to be processed and enters the CCD camera for imaging, the CCD camera finds the focus of the laser beam on the workpiece to be processed, so that the CCD camera is calibrated, and the electric positioning platform is adjusted by the control system, so that the movement processing platform enables the focus of the laser beam of the continuous laser and the pulse laser to be positioned at a proper cutting position in the workpiece to be processed. Therefore, when the focusing light beams of the first light path and the second light path are coaxially arranged, the same set of CCD focusing system can be shared; when the focusing light beams of the first light path and the second light path are arranged in a paraxial mode, the first light path and the second light path can be respectively provided with a set of CCD focusing system; meanwhile, the setting position of the CCD light source is not unique, the CCD light source can be positioned outside the first light path or the second light path and passes through the first light path or the second light path, and can also be arranged in the first light path or the second light path, only the light of the CCD light source is required to be focused to a workpiece to be processed through the focusing high-power objective lens and radiated to the CCD camera, and the realization of the aim of the invention is not influenced by the change of the setting position of the CCD light source.

It should be noted that the beam expander is intended to generate a larger light beam and obtain a larger incident diameter on the focusing objective lens to obtain a smaller light spot and a larger energy density, so that the focusing light beam of the first optical path and the focusing light beam of the second optical path may be arranged on the optical path by a plurality of arrangements, such as the beam expander, the beam splitter, the focusing high power objective lens, and other optical components, which may be arranged coaxially or paraxially, and according to different implementation requirements, the beam expander, the focusing high power objective lens, and other optical components may be shared to achieve reflection or focusing of the optical path without affecting the achievement of the object of the invention.

It should be noted that, on the second light path, a polarizer may be further disposed between the second beam expander and the second beam splitter, so that the polarizer can eliminate dazzling reflected light and scattered light, and make the messy light become parallel light, thereby improving the processing effect of the laser beam.

Compared with the prior art, the invention has the beneficial effects that:

(1) the invention combines the pre-modification of the material by continuous laser and the secondary modification of the pulse laser, so that the invisible cutting process becomes mild, the growth and the appearance of cracks can be controlled by adjusting the parameters of the laser, unexpected and uncontrollable cracks can not be generated by conventional invisible cutting, and the invention can be greatly suitable for materials with different thicknesses.

(2) The invention adopts the composite processing of the continuous laser and the pulse laser, so that the interference between the two lasers is not required to be considered, the time sequence distribution is not required to be considered, and any equipment is not required to be added to control the alternate light emitting of the two lasers, thereby simplifying the process and reducing the cost.

Drawings

FIG. 1 is a flowchart of the operation of example 1;

FIG. 2 is a schematic view of a laser modification process of a workpiece to be processed according to example 1;

FIG. 3 is a gold phase diagram of a modified region of the workpiece to be processed according to example 1;

FIG. 4 is a schematic diagram of the optical path in example 2;

fig. 5 is a schematic diagram of the optical path of embodiment 3.

The graphic symbols are illustrated as follows:

the method comprises the following steps of 1-a continuous laser, 2-a pulse laser, 3-a first beam expander, 4-a second beam expander, 5-a polaroid, 6-a first beam splitter, 7-a second beam splitter, 8-a third beam splitter, 9-a first focusing high-power objective lens, 10-a workpiece to be processed, 11-a motion processing platform, 12-a CCD camera, 121-a second CCD camera, 13-a CCD light source, 131-a second CCD light source, 81-a fourth beam splitter and 91-a second focusing high-power objective lens.

Detailed Description

The present invention will be further described with reference to the following embodiments. Wherein the showings are for the purpose of illustration only and are shown by way of illustration only and not in actual form, and are not to be construed as limiting the present patent; to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product; it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted.

The same or similar reference numerals in the drawings of the embodiments of the present invention correspond to the same or similar components; in the description of the present invention, it should be understood that if there is an orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", etc. based on the orientation or positional relationship shown in the drawings, it is only for convenience of describing the present invention and simplifying the description, but it is not intended to indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and are not to be construed as limiting the present patent, and the specific meaning of the terms may be understood by those skilled in the art according to specific circumstances.

Example 1

As shown in fig. 1 to 3, a double-laser composite invisible cutting method specifically includes the following steps:

s1: selecting a continuous laser 1 with the wavelength of 1030nm and a pulse laser 2 with the wavelength of 1030nm, the pulse width of 290fs, the single pulse energy of 40 muJ and the repetition frequency of 1kHz, controlling a motion processing platform 11 for placing a workpiece 10 to be processed to move to a processing position through a control system, and controlling a laser beam emitted by the continuous laser 1 to be focused to an initial cutting position of the workpiece 10 to be processed through a first light path and a laser beam emitted by the pulse laser 2 to be focused to the initial cutting position of the workpiece 10 to be processed through a second light path through the control system; in the embodiment, the workpiece 10 to be processed is glass;

s2: opening the continuous laser 1, controlling the motion processing platform 11 to move according to a set processing path by the control system, keeping the continuous laser 1 continuously emitting laser, and performing pre-modification on the workpiece 10 to be processed to form a pre-modified region;

s3: and (3) turning on the pulse laser 2, outputting laser with a specific frequency by the pulse laser 2, carrying out secondary modification in the pre-modified region along a preset cutting path, wherein the focal point of the pulse laser is 70 μm away from the surface to form a secondary modified region, and turning off the continuous laser 1 and the pulse laser 2 after finishing the secondary modification of the preset cutting path to finish the invisible cutting of the workpiece.

The embodiment also comprises the step of applying external force to the workpiece subjected to the invisible cutting along the cutting path by using the splitting machine so as to divide the workpiece along the cutting path.

In this way, the continuous laser 1 and the pulse laser 2 are selected to respectively emit continuous laser beams and pulse laser beams, the continuous laser is kept normally open, a pre-modified area is formed in the workpiece, and the pulse laser performs secondary modification in the pre-modified area formed by the continuous laser, so that the secondary modification process of the pulse laser becomes milder and controllable, the secondary modification effect of the pulse laser is improved, and the required energy of the pulse laser is greatly reduced; the continuous laser and the pulse laser do not work alternately but work, namely the pulse laser performs invisible cutting in the environment that the continuous laser irradiates, the moving processing platform 11 where the workpiece is located is moved in the cutting process, the whole workpiece can be cut, a series of cracks such as the shape of the invisible cutting crack, the length, the direction and the effect of the crack are controllable in forming related parameters through the pre-modification of a continuous laser spot and the ablation of the pulse laser, the actual operation difficulty is greatly reduced, and the effect of the invisible cutting after the cutting of the crack and the excellent rate of products are improved.

Example 2

As shown in fig. 4, a processing system used in a double-laser composite invisible cutting method includes a control system, a motion processing platform 11 for placing a workpiece 10 to be processed and moving according to a set processing path, a continuous laser 1 for emitting a continuous laser beam, a pulse laser 2 for emitting a pulse laser beam, a first optical path for focusing the continuous laser beam emitted by the continuous laser 1 on the workpiece 10 to be processed and pre-modifying the workpiece 10 to be processed to form a pre-modified region, and a second optical path for focusing the pulse laser beam emitted by the pulse laser 2 on the workpiece 10 to be processed and secondary modifying the pre-modified region to form a secondary modified region, wherein the continuous laser 1, the pulse laser 2, and the motion processing platform 11 are electrically connected to the control system; the laser cutting machine further comprises a focusing system for focusing the laser beams of the continuous laser 1 and the pulse laser 2 to an initial cutting position, and the focusing system is electrically connected with the control system.

As shown in fig. 4, the first optical path includes a first beam expander 3, a first beam splitter 6 and a first focusing high power objective lens 9, which are sequentially arranged, the laser beam emitted by the continuous laser 1 is expanded by the first beam expander 3, the beam is converted into a vertical direction by the first beam splitter 6, and the laser beam spot is focused into the workpiece to be processed by the first focusing high power objective lens 9; the second optical path comprises a second beam expander 4, a second beam splitter 7 and a first focusing high-power objective lens 9 which are sequentially arranged, laser emitted by the pulse laser 2 is expanded by the second beam expander 4, the light beam is converted into a vertical direction by the second beam splitter 7, and laser beam spots are focused into a workpiece to be processed by the first focusing high-power objective lens 9; the focusing system is a CCD focusing system, the CCD focusing system comprises a CCD light source 13 and a CCD camera 12, and a third light path, the light beam emitted by the CCD light source 13 reaches the surface of a workpiece 10 to be processed and is reflected to enter the CCD camera 12 for imaging, the third light path comprises a first focusing high-power objective lens 9 and a third spectroscope 8, after the light beam emitted by the CCD light source 13 is focused to the surface of the workpiece 10 to be processed through the first focusing high-power objective lens 9, the reflected light beam reversely passes through the first focusing high-power objective lens 9 and enters the CCD camera 12 for imaging through the direction change of the third spectroscope 8; on the second optical path, a polarizing plate 5 is further disposed between the second beam expander 4 and the second beam splitter 7.

In this embodiment, the first optical path and the second optical path are coaxially arranged in the focusing section, the optical paths of the focusing section are partially overlapped, the first optical path and the second optical path both pass through the second beam splitter 7 and the third beam splitter 8, and the first optical path and the second optical path share the first focusing high power objective lens 9;

in the embodiment, the CCD light source 13 of the focusing system is arranged outside the focusing section where the first optical path and the second optical path are coaxially arranged, and the third beam splitter 8 is arranged between the second beam splitter 7 and the first focusing high power objective lens 9;

in this embodiment, a laser beam of the continuous laser 1 is sequentially focused into a workpiece 10 to be processed through a first beam expander 3, a first beam splitter 6, a second beam splitter 7, a third beam splitter 8 and a first focusing high power objective 9; the laser beam of the pulse laser 2 is focused into a workpiece 10 to be processed through a second beam expander 4, a polaroid 5, a second spectroscope 7, a third spectroscope 8 and a first focusing high-power objective lens 9 in sequence; the light beam of the CCD light source 13 sequentially passes through the first spectroscope 6, the second spectroscope 7, the third spectroscope 8 and the first focusing high-power objective lens 9 to the surface of the workpiece 10 to be processed and reflected, and the reflected light beam reversely passes through the first focusing high-power objective lens 9 and is refracted by the third spectroscope 8 to enter the CCD camera 12 for imaging.

The focusing principle of the focusing system is as follows: and (3) opening a CCD light source 13 and a CCD camera 12, coaxially calibrating the continuous laser beam emitted by the continuous laser 1 and the pulse laser beam emitted by the pulse laser 2, and adjusting the bottom motion processing platform 11 after calibration so that the focuses of the laser beams of the continuous laser 1 and the pulse laser 2 are positioned at the proper cutting position of the workpiece 10 to be processed on the motion processing platform 11.

Example 3

As shown in fig. 5, a processing system used in a double-laser composite invisible cutting method includes a control system, a motion processing platform 11 for placing a workpiece 10 to be processed and moving according to a set processing path, a continuous laser 1 for emitting a continuous laser beam, a pulse laser 2 for emitting a pulse laser beam, a first optical path for focusing the continuous laser beam emitted by the continuous laser 1 on the workpiece 10 to be processed and pre-modifying the workpiece 10 to be processed to form a pre-modified region, and a second optical path for focusing the continuous laser beam emitted by the pulse laser 2 on the workpiece 10 to be processed and secondary modifying the pre-modified region to form a secondary modified region, wherein the continuous laser 1, the pulse laser 2, and the motion processing platform 11 are electrically connected to the control system; the laser cutting machine further comprises a focusing system for focusing the laser beams of the continuous laser 1 and the pulse laser 2 to an initial cutting position, and the focusing system is electrically connected with the control system.

11. As shown in fig. 5, the first optical path includes a first beam expander 3, a first beam splitter 6 and a first focusing high power objective lens 9, which are sequentially arranged, the laser beam emitted by the continuous laser 1 is expanded by the first beam expander 3, the beam is converted into a vertical direction by the first beam splitter 6, and the laser beam spot is focused into the workpiece to be processed by the first focusing high power objective lens 9; the second optical path comprises a second beam expander 4, a second beam splitter 7 and a second focusing high-power objective 91 which are sequentially arranged, laser emitted by the pulse laser 2 is expanded by the second beam expander 4, the light beam is converted into a vertical direction by the second beam splitter 7, and laser beam spots are focused into a workpiece to be processed by the second focusing high-power objective 91;

the focusing system comprises a first CCD focusing system and a second CCD focusing system, the first CCD focusing system comprises a CCD light source 13 and a CCD camera 12, a light beam emitted by the CCD light source 13 is transmitted to the surface of a workpiece 10 to be processed and reflected to enter a third light path of the CCD camera 12 for imaging, the third light path comprises a first focusing high-power objective lens 9 and a third beam splitter 8, after the light beam emitted by the CCD light source 13 is focused to the surface of the workpiece 10 to be processed through the first focusing high-power objective lens 9, the reflected light beam reversely passes through the first focusing high-power objective lens 9 and enters the CCD camera 12 for imaging through the direction change of the third beam splitter 8; the second CCD focusing system comprises a second CCD light source 131 and a second CCD camera 121, and a fourth light path for transmitting the light beam emitted by the second CCD light source 131 to the surface of the workpiece 10 to be processed and reflecting the light beam into the second CCD camera 121 for imaging, wherein the fourth light path comprises a second focusing high-power objective 91 and a fourth spectroscope 81, after the light beam emitted by the second CCD light source 131 is focused to the surface of the workpiece 10 to be processed by the second focusing high-power objective 91, the reflected light beam reversely passes through the second focusing high-power objective 91 and enters the second CCD camera 121 for imaging by changing the direction of the fourth spectroscope 81; on the second optical path, a polarizing plate 5 is further disposed between the second beam expander 4 and the second beam splitter 7.

In this embodiment, the first optical path and the second optical path are paraxial in the focusing section, and the first CCD focusing system and the second CCD focusing system are respectively disposed in the focusing section of the first optical path and the second optical path; the CCD light source 13 of the first CCD focusing system is arranged outside the focusing section of the first optical path, the second CCD light source 131 of the second CCD focusing system is arranged outside the focusing section of the second optical path, the third beam splitter 8 is arranged between the first beam splitter 6 and the first focusing high-power objective lens 9, and the fourth beam splitter 81 is arranged between the second focusing high-power objective lens 91 and the second beam splitter 7.

In this embodiment, a laser beam of the continuous laser 1 sequentially passes through the first beam expander 3, the first beam splitter 6, the third beam splitter 8 and the first focusing high power objective lens 9 and is focused into a workpiece 10 to be processed; the laser beam of the pulse laser 2 is focused into the workpiece 10 to be processed through the second beam expander 4, the polaroid 5, the second spectroscope 7, the fourth spectroscope 81 and the second focusing high-power objective 91 in sequence; the light beam of the CCD light source 13 sequentially passes through the first spectroscope 6, the third spectroscope 8 and the first focusing high-power objective lens 9 to reach the surface of the workpiece 10 to be processed and is reflected, and the reflected light beam reversely passes through the first focusing high-power objective lens 9 and is refracted by the third spectroscope 8 to be turned to enter the CCD camera 12 for imaging; the light beam of the second CCD light source 131 sequentially passes through the second beam splitter 7, the fourth beam splitter 81 and the second focusing high power objective 91 to the surface of the workpiece 10 to be processed and reflected, and the reflected light beam reversely passes through the second focusing high power objective 91 and is refracted by the fourth beam splitter 81 and turned to enter the second CCD camera 121 for imaging.

The focusing principle of the focusing system is as follows: and respectively turning on the CCD light source 13, the CCD camera 12, the second CCD light source 131 and the second CCD camera 121, respectively carrying out coaxial calibration on the continuous laser beam emitted by the continuous laser 1 and the pulse laser beam emitted by the pulse laser 2, and adjusting the bottom motion processing platform 11 after calibration so that the focuses of the laser beams of the continuous laser 1 and the pulse laser 2 are positioned at the proper cutting position of the workpiece 10 to be processed on the motion processing platform 11.

It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.