CN117161547A - Anti-return laser processing head and processing equipment - Google Patents

Abstract

The invention discloses an anti-return pulse laser processing head and processing equipment, comprising a laser scanning galvanometer, a flat field focusing lens, at least two collimating lenses, and an optical fiber output laser module correspondingly arranged in front of each collimating lens, wherein: the collimating lenses are used for converting the light output by the end face of the output optical fiber of the corresponding optical fiber output laser module into parallel light, and the collimating lenses are arranged in parallel; the laser scanning galvanometer is arranged on the output light path of the collimating lenses and is used for realizing one-dimensional or two-dimensional scanning; the flat field focusing lens is arranged on an output light path of the laser scanning galvanometer and is used for converging light beams from the laser scanning galvanometer into a plurality of light spots; the invention can greatly reduce the back light structurally through reasonable structural design, and directly adopts the low-power laser module to optimize and delete the beam combining link, thereby greatly reducing the equipment cost.

Description

Anti-return laser processing head and processing equipment

Technical Field

The invention belongs to the technical field of laser 3D processing, and particularly relates to an anti-return laser processing head and processing equipment.

Background

The pulse laser can provide extremely high peak power in extremely short time to process the surface of the material in a tiny area, such as surface carving, marking, cleaning, cutting, welding and the like, can process various materials such as metal materials, inorganic brittle materials, plastics and the like, and can process the inside of transparent materials. With the increasing processing demands, the requirements on the energy of laser processing light spots are increasing, and pulse lasers with higher average power are required. While the improvement of the average power of the pulse laser is limited by the laser device and the material characteristics, the current high-power laser is usually formed by combining a plurality of low-power lasers by a fiber combiner. The laser beam combining technology is characterized in that the degradation of the quality of the laser beam is large, and the design of a laser processing optical system is not facilitated. In addition, since pulsed lasers are relatively sensitive to retro-reflected light, it is often necessary to provide an optical isolator in the optical path, which has limited light tolerance due to limitations in materials and device characteristics, is technically difficult to meet and is expensive. In pulse laser processing systems, it is sometimes desirable to employ continuous light for auxiliary processing, and existing solutions employ two sets of laser systems for simultaneous processing, increasing system cost and complexity.

Disclosure of Invention

In order to solve the problems in the prior art, the invention aims to provide an anti-return laser processing head and processing equipment, which can greatly reduce return light structurally through reasonable structural design, and directly adopts a low-power laser module to optimize and delete a beam combining link, thereby greatly reducing equipment cost.

In order to achieve the above object, the present invention provides an anti-return laser processing head, which includes a laser scanning galvanometer, a flat-field focusing lens, at least two collimating lenses, and an optical fiber output laser module correspondingly disposed in front of each collimating lens, wherein:

the collimating lenses are used for converting the light output by the end face of the output optical fiber of the corresponding optical fiber output laser module into parallel light, and all the collimating lenses are arranged in parallel;

the laser scanning galvanometer is arranged on an output light path of the collimating lens and is used for realizing one-dimensional or two-dimensional scanning;

the flat field focusing lens is arranged on an output light path of the laser scanning galvanometer and is used for converging light beams from the laser scanning galvanometer into a plurality of light spots;

the optical fiber output laser module comprises pulse laser modules which work synchronously with each other; wherein:

sub-beams from the corresponding collimating lenses at the light emergent end of the flat-field focusing lens are not parallel to the optical axis of the flat-field focusing lens;

the paths of specular reflection light generated by the surface of any sub-beam perpendicular to the optical axis of the flat-field focusing lens and other sub-beams are not overlapped;

the specular reflection light generated by the surface of any light ray in any sub-beam perpendicular to the optical axis of the flat-field focusing lens is not coincident with the paths of other light rays in the sub-beam.

Further, the optical axis of the collimating lens is parallel and parallel to the optical axis of the flat field focusing lens; the position of the optical fiber output end face of the optical fiber output laser module, the shape of the optical fiber core, the size of the optical fiber core, the focal length of the corresponding collimating lens and the focal length of the flat field focusing lens are adjusted, so that the imaging of the optical fiber output end face of all the optical fiber output laser modules, which is formed near the focal plane after passing through the corresponding collimating lens and the flat field focusing lens, is overlapped together to form a spot; or images formed near the focal plane are arranged together to form a line spot.

The invention also provides an anti-return laser processing head, which comprises a dynamic focusing lens, a laser scanning galvanometer, at least two collimating lenses and an optical fiber output laser module correspondingly arranged in front of each collimating lens; wherein:

the collimating lenses are used for converting light output by the end face of the output optical fiber of the corresponding optical fiber output laser module into parallel light, and all the collimating lenses are arranged in parallel;

the dynamic focusing lens is arranged in an output light path of the collimating lens, and light from the collimating lens is converged into a plurality of light spots distributed on a back focal plane according to a certain rule; the dynamic focusing lens comprises at least one lens capable of moving along the optical axis direction of the lens and is used for enabling the converged light spots to move along the optical axis direction;

the laser scanning galvanometer is positioned in an output light path of the dynamic focusing lens and is used for realizing one-dimensional or two-dimensional angle scanning; the dynamic focusing lens and the laser scanning galvanometer work cooperatively and are used for enabling all light spots from the collimating lens to scan on a three-dimensional space behind the dynamic focusing lens; the optical fiber output laser module comprises pulse laser modules which work synchronously with each other; wherein:

all sub-beams from the corresponding collimating lens at the light emergent end of the dynamic focusing lens are not parallel to the optical axis of the dynamic focusing lens; the paths of specular reflection light generated by the surface of any sub-beam perpendicular to the optical axis of the dynamic focusing lens and other sub-beams are not overlapped; the specular reflection light generated by the surface of any light ray in any sub-beam perpendicular to the optical axis of the dynamic focusing lens is not coincident with the paths of other light rays in the sub-beam.

Further, the optical axis of the collimating lens is parallel and parallel to the optical axis of the dynamic focusing lens; and by adjusting the position of the optical fiber output end face, the shape of the fiber core, the size of the fiber core, the focal length of the corresponding collimating lens and the focal length of the dynamic focusing lens, the imaging formed on the image surface of all the optical fiber output laser module output optical fiber end faces after passing through the corresponding collimating lens and the dynamic focusing lens is overlapped to form spot light spots, or the imaging formed on the image surface is arrayed together to form line light spots.

Further, the dynamic focusing lens comprises a negative lens light group and a positive lens light group; the negative lens light group is arranged close to the collimating lens and is used for enabling a plurality of parallel light beams from the collimating lens to become emitted light from a plurality of virtual image points; the positive lens light group is used for converging light from the negative lens light group to an image surface behind the positive lens light group;

the negative lens light group is movable in a direction parallel to the optical axis.

Furthermore, at least one return light detection system is arranged in the end face area of the output optical fibers of all the collimating lenses or all the optical fiber output laser modules.

Further, each optical fiber output laser module is correspondingly provided with a return light detection system; the return light detection system is a photoelectric detector and is arranged near the end face of each optical fiber output laser module output optical fiber;

or the return light detection system comprises a photoelectric detector and a detection optical fiber, wherein one end of the detection optical fiber is arranged near the end face of the output optical fiber of the optical fiber output laser module, and the other end irradiates the detected return light on the photoelectric detector.

Further, the return light detection system comprises a detection lens and a photoelectric detector; the optical axis of the detection lens is coincident with the optical axis of the flat-field focusing lens or the dynamic focusing lens, and light returned by the flat-field focusing lens or the dynamic focusing lens is converged on the photoelectric detector;

or the return light detection system comprises a detection lens, an optical fiber and a photoelectric detector, wherein the optical axis of the detection lens coincides with the optical axis of the flat-field focusing lens or the dynamic focusing lens, the return light detection system is used for converging the light returned by the flat-field focusing lens or the dynamic focusing lens onto one end face of the detection optical fiber, and the light output by the other end face of the detection optical fiber irradiates the photoelectric detector.

Further, an optical isolator is correspondingly arranged at the position close to the light emitting end of each collimating lens;

the optical fiber output laser module also comprises at least one continuous light laser module.

Furthermore, the invention also provides laser processing equipment, which comprises the anti-return light laser-resistant processing head.

Compared with the prior art, the anti-return laser processing head provided by the invention has the advantages that a plurality of low-power laser modules are directly adopted as light sources, so that the use of an optical fiber beam combiner in the prior art is eliminated, and the equipment cost is reduced; and through reasonable setting of the position of the collimating lens, the influence of return light can be greatly reduced, the use of an isolator can be eliminated in most applications, and the cost is reduced.

Furthermore, the sub-beams generated by each collimating lens can be mutually not interfered by the back reflection light generated by the processing surface perpendicular to the optical axis of the flat-field focusing lens and cannot return to the receiving aperture of the collimating lens. Thereby greatly reducing the influence of back light in the processing process. The spot light forming scheme can form a high-power processing light spot. The arrangement of forming the line spot and directing the line perpendicular to the scan direction may improve processing efficiency in certain applications. Can flexibly produce light spots with various structures, is suitable for different processing requirements, and has high flexibility and strong adaptability.

Furthermore, by limiting the position of the collimating lens, the specular reflection light generated by any sub-beam in the processing process cannot enter other optical fiber output laser modules, and cannot enter the optical fiber output laser modules for generating the sub-beam, so that the influence of return light reflection on the optical fiber output laser modules can be greatly reduced.

Furthermore, the invention has reasonable structural design, and can increase the performance by arranging the low-power isolator in some places with high requirements on the return light reflection, thereby increasing the technical feasibility and reducing the cost.

Furthermore, by arranging a return light detection system at each input module, the corresponding laser module can be closed in real time under certain extreme conditions, and the continuity of work can not be affected because each module has limited influence on total energy. In addition, by arranging the return light detection system, the invention can monitor the laser processing effect in real time.

Furthermore, the beam quality after beam combination is far better than that which can be achieved by the existing tapering technology, the precision requirement on the mechanical movement part of the pulse laser processing equipment can be greatly relaxed, and the cost is reduced; meanwhile, the complexity of the optical system can be reduced, and the cost is reduced.

Furthermore, by integrating the pulse light source and the continuous light source into one optical system, the system complexity is reduced, the cost is effectively reduced, and the efficiency is improved.

Compared with the existing equipment, the equipment adopting the anti-return laser processing head provided by the invention has the characteristics of low cost and good work continuity.

Drawings

Fig. 1 is a schematic structural diagram of an anti-return laser processing head using a flat field focusing lens according to the present invention.

Fig. 2 is a schematic structural diagram of an anti-return laser processing head using a dynamic focusing lens according to the present invention.

Fig. 3 is a schematic structural diagram of an embodiment of an anti-return laser processing head using a dynamic focusing lens according to the present invention.

Fig. 4 is a schematic diagram of an implementation structure of a collimator lens arrangement of an anti-return laser processing head using a flat field focusing lens according to the present invention.

Fig. 5 is a schematic diagram of an implementation structure of an anti-return laser processing head using a flat-field focusing lens according to the present invention, in which a return detection system is used.

Fig. 6 shows an implementation structure of the anti-return laser processing head using dynamic focusing lens using an optical isolator according to the present invention.

Wherein: m-1 and M-N respectively represent optical fiber output laser modules; ZZ-1 and ZZ-N respectively represent a collimating lens; SMZJ represents a laser scanning galvanometer; DJJJ represents a dynamic focusing lens, DJJ-1 represents a negative lens light group in the dynamic focusing lens, and DJJ-1 represents a positive lens light group in the dynamic focusing lens; PCJJJ represents a flat field focus lens; GLQ-1 and GLQ-N respectively represent an isolator; TCQ, TCQ-1, TCQ-N represent detectors, respectively; TCJT denotes a probe lens; TCGX, TCGX-1, TCGX-N denote detection fibers.

Detailed Description

The anti-return laser processing head and the device provided by the invention are described in detail below with reference to the accompanying drawings and the specific embodiments.

The technical scheme of the anti-return laser processing head adopting the flat field focusing lens is shown in figure 1. The processing head comprises at least two collimating lenses, a laser scanning galvanometer and a flat-field focusing lens which are sequentially arranged, and further comprises an optical fiber output laser module which is correspondingly arranged in front of each collimating lens. Wherein: the collimating lenses ZZ-1, … and ZZ-N are arranged in parallel, namely the optical axes of the collimating lenses are arranged side by side in space according to a certain interval; the optical fiber laser device is used for respectively converting light output by the output optical fiber end faces of the optical fiber output laser modules M-1, … and M-N arranged on the front focal plane of the collimating lens into parallel light; the laser scanning galvanometer SMZJ is arranged on the output light path of the collimating lenses and is used for realizing one-dimensional or two-dimensional scanning of the angular space; the flat field focusing lens PCJJJ is arranged on an output light path of the laser scanning vibrating mirror SMZJ, and all light beams from the laser scanning vibrating mirror SMZJ are converged to form a combined light spot; the optical fiber output laser modules can be pulse laser modules and work synchronously; in some embodiments of the invention, the fiber output laser modules may also contain continuous-light laser modules that assist the pulsed laser modules in operation;

wherein: the positions of the collimating lenses are arranged so that sub-beams from the corresponding collimating lenses at the light emergent end of the flat-field focusing lens are not parallel to the optical axis of the flat-field focusing lens, the paths of specular reflection light generated by the surface of any sub-beam perpendicular to the optical axis of the flat-field focusing lens are not coincident with the paths of other sub-beams, and the paths of specular reflection light generated by the surface of any light in any sub-beam perpendicular to the optical axis of the flat-field focusing lens are not coincident with the paths of other light in the sub-beams. The arrangement ensures that the specular reflection light generated by any sub-beam in the processing process does not enter other optical fiber output laser modules and also does not enter the optical fiber output laser module generating the sub-beam, thereby greatly reducing the influence of return light reflection on the optical fiber output laser modules.

The system can integrate pulsed light and continuous light, and the flexibility of the system is increased. For example, in the composite laser cleaning, continuous light is used as a bottom light source to preheat an object, so that the cleaning efficiency is remarkably improved!

Fig. 4 is a schematic diagram of an implementation structure of a collimator lens arrangement of an anti-return laser processing head using a flat field focusing lens according to the present invention. The optical axes of the three collimating lenses ZZ-1, ZZ-2 and ZZ-3 are parallel to the optical axis of the flat field focusing lens PJJJ, and the optical axes of the three collimating lenses are arranged on a cylindrical surface taking the optical axis of the flat field focusing lens as the center and distributed at 120 degrees. Obviously, the sub-beams generated by each collimating lens can be mutually not interfered by the back reflection light generated by the processing surface perpendicular to the optical axis of the flat-field focusing lens and cannot return to the receiving aperture of the collimating lens. Thereby greatly reducing the influence of back light in the processing process.

In this technical solution, preferably, the optical axes of the collimating lenses are parallel and parallel to the optical axis of the flat-field focusing lens; the positions of the optical fiber output end faces of the optical fiber output laser modules, the shapes of the optical fiber cores, the sizes of the optical fiber cores, the focal lengths of the corresponding collimating lenses and the focal lengths of the flat-field focusing lenses are adjusted, so that the imaging of the optical fiber output end faces of the optical fiber output laser modules, which are formed near the focal plane, is overlapped together to form spot light spots after passing through the corresponding collimating lenses and the flat-field focusing lenses; or, the end faces of the output optical fibers of the optical fiber output laser modules pass through the corresponding collimating lenses and the flat-field focusing lenses and then are arrayed together to form line light spots. The spot light forming scheme can form a high-power processing light spot. The arrangement of forming the line spot and directing the line perpendicular to the scan direction may improve processing efficiency in certain applications.

The technical scheme of the anti-return laser processing head adopting the dynamic focusing lens is shown in fig. 2. The processing head comprises at least two collimating lenses, a dynamic focusing lens, a laser scanning galvanometer and an optical fiber output laser module correspondingly arranged in front of each collimating lens. Wherein: the collimating lenses ZZ-1, … and ZZ-N are arranged in parallel, the optical axes of the collimating lenses are arranged side by side at a certain interval, and the collimating lenses are respectively used for converting the light output by the output optical fiber end faces of the optical fiber output laser modules M-1, … and M-N arranged on the front focal surfaces of the collimating lenses into parallel light; the dynamic focusing lens DJJJ is arranged in an output light path of the collimating lenses, and light from the collimating lenses is converged into a plurality of light spots distributed on a back focal plane according to a certain rule; the dynamic focusing lens DJJJ at least comprises a lens which can move along the optical axis direction of the lens and can enable the converged light spots to move along the optical axis direction; the laser scanning galvanometer SMZJ is positioned in an output light path of the dynamic focusing lens and is used for realizing one-dimensional or two-dimensional angle scanning. The dynamic focusing lens DJJ and the laser scanning vibrating mirror SMZJ work cooperatively to scan the light spots from the collimating lenses on a three-dimensional space behind the dynamic focusing lens; the optical fiber output laser modules can be pulse laser modules and work synchronously; the optical fiber output laser modules can also comprise continuous light laser modules which assist the pulse laser modules to work; the technical scheme can realize laser processing in a three-dimensional space. Wherein: the positions of the collimating lenses are set so that sub-beams from the corresponding collimating lenses at the light emergent end of the dynamic focusing lens are not parallel to the optical axis of the dynamic focusing lens, the paths of specular reflection light generated by the surface of any sub-beam perpendicular to the optical axis of the dynamic focusing lens are not coincident with the paths of other sub-beams, and the paths of specular reflection light generated by the surface of any light in any sub-beam perpendicular to the optical axis of the dynamic focusing lens are not coincident with the paths of other light in the sub-beam. The arrangement ensures that the specular reflection light generated by any sub-beam in the processing process does not enter other optical fiber output laser modules and also does not enter the optical fiber output laser module generating the sub-beam, thereby greatly reducing the influence of return light reflection on the optical fiber output laser modules.

The system can integrate pulsed light and continuous light, and the flexibility of the system is increased. For example, in the composite laser cleaning, continuous light is used as a bottom light source to preheat an object, so that the cleaning efficiency is remarkably improved!

In this technical solution, preferably, the optical axes of the collimating lenses are parallel and parallel to the optical axis of the dynamic focusing lens; the positions of the optical fiber output end faces of the optical fiber output laser modules, the shapes of the optical fiber cores, the sizes of the optical fiber cores, the focal lengths of the corresponding collimating lenses and the focal lengths of the dynamic focusing lenses are adjusted, so that the imaging of the optical fiber output end faces of the optical fiber output laser modules on the image surface is overlapped to form spot light spots after passing through the corresponding collimating lenses and the dynamic focusing lenses, or the imaging of the optical fiber output end faces of the optical fiber output laser modules on the image surface is arrayed to form line light spots after passing through the corresponding collimating lenses and the dynamic focusing lenses. The spot light forming scheme can form a high-power processing light spot. The arrangement of forming the line spot and directing the line perpendicular to the scan direction may improve processing efficiency in certain applications.

In this technical solution, preferably, the dynamic focusing lens includes a negative lens light group and a positive lens light group; the negative lens light group is arranged close to the collimating lens, so that a plurality of parallel light beams from the collimating lenses are changed into emission light from a plurality of virtual image points; the positive lens light group gathers the light from the negative lens light group onto the image surface behind it; the negative lens optics may be movable in a direction parallel to the optical axis.

Fig. 3 is a schematic structural diagram of an embodiment of an anti-return laser processing head using a dynamic focusing lens according to the present invention. The dynamic focusing lens DJJ consists of a negative lens light group DJJ-1 and a positive lens light group DJJ-2, and the position of the light spot along the optical axis direction is controlled by the movement of the negative lens light group DJJ-1. And the dynamic focusing lens DJJJ and the laser scanning galvanometer SMZJ are combined to realize three-dimensional space processing. The dynamic focusing mirror in the mode can greatly reduce the movement distance of the components in the dynamic focusing mirror and reduce the implementation difficulty.

Further, in the above technical solution, at least one return light detection system is provided in the output fiber end face area of the collimator lenses or the fiber output laser modules. The back light detector is used for monitoring the back reflection light in real time in the laser processing process.

Preferably, each optical fiber output laser module is correspondingly provided with a return light detection system; the return light detection system can be a photoelectric detector which is arranged near the end face of the output optical fiber of each optical fiber output laser module; the return light detection system can also comprise a photoelectric detector and a detection optical fiber, wherein one end of the detection optical fiber is arranged near the end face of the output optical fiber of the optical fiber output laser module, and the other end irradiates the detected return light on the photoelectric detector.

Preferably, the return light detection system comprises a detection lens and a photoelectric detector, wherein the optical axis of the detection lens coincides with the optical axis of the flat field focusing lens or the dynamic focusing lens, and light returned by the flat field focusing lens or the dynamic focusing lens is converged on the photoelectric detector. The return light detection system can also comprise a detection lens, an optical fiber and a photoelectric detector, wherein the optical axis of the detection lens coincides with the optical axis of the flat-field focusing lens or the dynamic focusing lens, light returned by the flat-field focusing lens or the dynamic focusing lens is converged on one end face of the detection optical fiber, and light output by the other end of the detection optical fiber irradiates the photoelectric detector.

Fig. 5 is a schematic diagram of an implementation structure of an anti-return laser processing head using a flat-field focusing lens according to the present invention, in which a return detection system is used. In the laser processing head, each optical fiber output laser module is correspondingly provided with a return light detection system for monitoring the return reflected light returned to the optical fiber output laser module. Each return light detection system comprises a detection optical fiber and a photoelectric detector, one end of the detection optical fiber is arranged near the end face of the output optical fiber of the corresponding optical fiber output laser module and used for receiving return light, and the other end of the detection optical fiber is connected with the photoelectric detector. In addition, the laser processing head provided by the invention is also provided with a return light detection system which is used for monitoring the total return light in the processing process and can evaluate the processing quality. The return light detection system comprises a detection lens TCJT, a detection optical fiber TCGX and a photoelectric detector TCQ, wherein the detection lens converges return reflected light from the flat-field focusing lens to the end face of the detection optical fiber TCGX, and the detection optical fiber TCGX irradiates the received light to the photoelectric detector TCQ.

Further, an optical isolator is correspondingly arranged at the close vicinity of the light emitting end of each collimating lens.

Fig. 6 shows an implementation structure of the anti-return laser processing head using dynamic focusing lens using an optical isolator according to the present invention. In the processing head, an optical isolator is arranged behind each collimating lens, so that the back reflection light can be further isolated. The system is used in systems that use fiber optic output laser modules that require higher demands for retroreflection.

The invention provides laser processing equipment which comprises at least one anti-return laser processing head.

Example 1: according to the technical scheme shown in the figure, in a certain embodiment, an anti-return laser cleaning head for generating round light spots is developed, and the technical parameters are as follows: 1. the number of the optical fiber output laser modules is 3, the average power output by each module is 200 watts, the output optical core diameter is 30 micrometers, the numerical aperture is 0.06, the repetition frequency is 130 to 2000kHz, and the pulse width is adjustable from 10 nanoseconds to 350 nanoseconds; 2. number of collimator lenses: 3, focal length is 18 mm, and the focal length is uniformly distributed on the circumference with the diameter of 4.32 mm; 3. the scanning galvanometer adopts a one-dimensional galvanometer, and the maximum beam caliber is 7 mm; 4. focal length of flat field focusing lens: 360 mm; 5. spot size: 0.6 mm. In this embodiment, the optical parameter product of the cleaning spot is 2.7 mm milliradians. The pulse fiber laser for a certain commodity in the current market is generated as follows: average power 500W, output fiber 200 microns, numerical aperture 0.22, optical parameter product 22 mm milliarc-! It is apparent that the embodiments give a system with a beam quality far superior to existing devices.

Example 2: according to the technical scheme shown in the second drawing, in a certain embodiment, an anti-return laser cleaning head for generating line light spots is developed, and the technical parameters are as follows: 1. the number of the optical fiber output laser modules is 3, the average power output by each module is 200 watts, the output optical core diameter is 30 micrometers, the numerical aperture is 0.06, the repetition frequency is 130 to 2000kHz, and the pulse width is adjustable from 10 nanoseconds to 350 nanoseconds; 2. number of collimator lenses: 3, focal length is 18 mm, and the focal length is uniformly distributed on the circumference with the diameter of 4.32 mm; 3. the scanning galvanometer adopts a one-dimensional galvanometer, and the maximum beam caliber is 7 mm; 4. dynamic focus lens focal length: 216 mm; 5. spot size: the line light spot trend is perpendicular to the scanning direction of the laser scanning galvanometer by 0.36 mm X0.9 mm.

Example 3: according to the technical scheme shown in the second drawing, in a certain embodiment, an anti-return laser cutting head is developed, and the technical parameters are as follows: 1. the number of the optical fiber output laser modules is 3, the average power output by each module is 80 watts, the output optical core diameter is 14 microns, the numerical aperture is 0.09, the repetition frequency is 130 to 2000kHz, and the pulse width is adjustable from 10 nanoseconds to 350 nanoseconds; 2. number of collimator lenses: 3, the focal length is 30 mm, and the focal length is uniformly distributed on the circumference with the diameter of 10 mm; 3. the scanning galvanometer adopts a two-dimensional galvanometer, and the maximum beam caliber is 16 mm; 4. dynamic focus lens focal length: 150 mm; 5. spot size: 0.07 mm. The system can be used for glass cutting.

Example 4: according to the technical scheme shown in the figure one, in a certain embodiment, an anti-return compound laser cleaning head for generating round light spots is developed, and the technical parameters are as follows: 1. the number of the optical fiber output laser modules is 3, wherein the optical fiber output laser modules comprises two pulse laser modules and one continuous light laser module, the average power of each pulse laser module is 200 watts, the output optical core diameter is 30 micrometers, the numerical aperture is 0.06, the repetition frequency is 130-2000 kHz, the pulse width is adjustable for 10 nanoseconds to 350 nanoseconds, the power of the continuous light laser module is 500 watts, the output optical fiber core diameter is 20 micrometers, and the numerical aperture is 0.06; 2. number of collimator lenses: 3, the focal lengths of the two collimating lenses corresponding to the pulse light are 18 mm, the focal length of the collimating lens corresponding to the continuous light is 7.2 mm, and the two collimating lenses are uniformly distributed on the circumference with the diameter of 4.32 mm; 3. the scanning galvanometer adopts a one-dimensional galvanometer, and the maximum beam caliber is 7 mm; 4. focal length of flat field focusing lens: 360 mm; 5. pulsed light spot size: 0.6 mm, a continuous spot size of 1 mm. In this embodiment, the energy of the continuous spot light injection preheats the substrate, which can greatly increase the cleaning speed.

According to the technical scheme of the anti-return laser processing head, the beam combining part of the laser is eliminated, so that the cost of the laser can be reduced, and meanwhile, the cost of laser processing equipment is further reduced because an optical isolator and a low-power isolator are not required. In addition, the processing head can flexibly generate light spots with different structures, and can integrate pulse laser and continuous laser in one system to apply different processing requirements.

Claims (10)

1. An anti-return laser processing head is characterized in that: the device comprises a laser scanning galvanometer, a flat field focusing lens, at least two collimating lenses, and an optical fiber output laser module which is correspondingly arranged in front of each collimating lens, wherein:

the collimating lenses are used for converting the light output by the end face of the output optical fiber of the corresponding optical fiber output laser module into parallel light, and all the collimating lenses are arranged in parallel;

the laser scanning galvanometer is arranged on an output light path of the collimating lens and is used for realizing one-dimensional or two-dimensional scanning;

the flat field focusing lens is arranged on an output light path of the laser scanning galvanometer and is used for converging light beams from the laser scanning galvanometer into a plurality of light spots;

the optical fiber output laser module comprises pulse laser modules which work synchronously with each other; wherein:

sub-beams from the corresponding collimating lenses at the light emergent end of the flat-field focusing lens are not parallel to the optical axis of the flat-field focusing lens;

the paths of specular reflection light generated by the surface of any sub-beam perpendicular to the optical axis of the flat-field focusing lens and other sub-beams are not overlapped;

the specular reflection light generated by the surface of any light ray in any sub-beam perpendicular to the optical axis of the flat-field focusing lens is not coincident with the paths of other light rays in the sub-beam.

2. The anti-return laser processing head of claim 1, wherein: the optical axis of the collimating lens is parallel to the optical axis of the flat-field focusing lens; the position of the optical fiber output end face of the optical fiber output laser module, the shape of the optical fiber core, the size of the optical fiber core, the focal length of the corresponding collimating lens and the focal length of the flat field focusing lens are adjusted, so that the imaging of the optical fiber output end face of all the optical fiber output laser modules, which is formed near the focal plane after passing through the corresponding collimating lens and the flat field focusing lens, is overlapped together to form a spot; or images formed near the focal plane are arranged together to form a line spot.

3. An anti-return laser processing head is characterized in that: the laser scanning device comprises a dynamic focusing lens, a laser scanning galvanometer, at least two collimating lenses and an optical fiber output laser module correspondingly arranged in front of each collimating lens; wherein:

the collimating lenses are used for converting light output by the end face of the output optical fiber of the corresponding optical fiber output laser module into parallel light, and all the collimating lenses are arranged in parallel;

the dynamic focusing lens is arranged in an output light path of the collimating lens, and light from the collimating lens is converged into a plurality of light spots distributed on a back focal plane according to a certain rule; the dynamic focusing lens comprises at least one lens capable of moving along the optical axis direction of the lens and is used for enabling the converged light spots to move along the optical axis direction;

the laser scanning galvanometer is positioned in an output light path of the dynamic focusing lens and is used for realizing one-dimensional or two-dimensional angle scanning; the dynamic focusing lens and the laser scanning galvanometer work cooperatively and are used for enabling all light spots from the collimating lens to scan on a three-dimensional space behind the dynamic focusing lens; the optical fiber output laser module comprises pulse laser modules which work synchronously with each other; wherein:

all sub-beams from the corresponding collimating lens at the light emergent end of the dynamic focusing lens are not parallel to the optical axis of the dynamic focusing lens; the paths of specular reflection light generated by the surface of any sub-beam perpendicular to the optical axis of the dynamic focusing lens and other sub-beams are not overlapped; the specular reflection light generated by the surface of any light ray in any sub-beam perpendicular to the optical axis of the dynamic focusing lens is not coincident with the paths of other light rays in the sub-beam.

4. A return-preventing laser processing head according to claim 3, characterized in that: the optical axis of the collimating lens is parallel to the optical axis of the dynamic focusing lens; and by adjusting the position of the optical fiber output end face, the shape of the fiber core, the size of the fiber core, the focal length of the corresponding collimating lens and the focal length of the dynamic focusing lens, the imaging formed on the image surface of all the optical fiber output laser module output optical fiber end faces after passing through the corresponding collimating lens and the dynamic focusing lens is overlapped to form spot light spots, or the imaging formed on the image surface is arrayed together to form line light spots.

5. A return-preventing laser processing head according to claim 3, characterized in that: the dynamic focusing lens comprises a negative lens light group and a positive lens light group; the negative lens light group is arranged close to the collimating lens and is used for enabling a plurality of parallel light beams from the collimating lens to become emitted light from a plurality of virtual image points; the positive lens light group is used for converging light from the negative lens light group to an image surface behind the positive lens light group;

the negative lens light group is movable in a direction parallel to the optical axis.

6. The anti-return laser processing head according to any one of claims 1 to 5, characterized in that: at least one return light detection system is arranged in the end face area of the output optical fibers of all the collimating lenses or all the optical fiber output laser modules.

7. The anti-return laser processing head of claim 6, wherein: each optical fiber output laser module is correspondingly provided with a return light detection system; the return light detection system is a photoelectric detector and is arranged near the end face of each optical fiber output laser module output optical fiber;

or the return light detection system comprises a photoelectric detector and a detection optical fiber, wherein one end of the detection optical fiber is arranged near the end face of the output optical fiber of the optical fiber output laser module, and the other end irradiates the detected return light on the photoelectric detector.

8. The anti-return laser processing head of claim 6, wherein: the return light detection system comprises a detection lens and a photoelectric detector; the optical axis of the detection lens is coincident with the optical axis of the flat-field focusing lens or the dynamic focusing lens, and light returned by the flat-field focusing lens or the dynamic focusing lens is converged on the photoelectric detector;

or the return light detection system comprises a detection lens, an optical fiber and a photoelectric detector, wherein the optical axis of the detection lens coincides with the optical axis of the flat-field focusing lens or the dynamic focusing lens, the return light detection system is used for converging the light returned by the flat-field focusing lens or the dynamic focusing lens onto one end face of the detection optical fiber, and the light output by the other end face of the detection optical fiber irradiates the photoelectric detector.

9. A return-preventing laser processing head according to any one of claims 1 or 3, characterized in that: an optical isolator is correspondingly arranged at the position close to the light emitting end of each collimating lens;

the optical fiber output laser module also comprises at least one continuous light laser module.

10. A laser processing apparatus, characterized by: comprising at least one anti-return laser processing head according to any of claims 1 to 9.