WO2021027659A1 - 基于多个光纤输出激光模块的复合光斑激光系统及加工头 - Google Patents

基于多个光纤输出激光模块的复合光斑激光系统及加工头 Download PDF

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WO2021027659A1
WO2021027659A1 PCT/CN2020/107131 CN2020107131W WO2021027659A1 WO 2021027659 A1 WO2021027659 A1 WO 2021027659A1 CN 2020107131 W CN2020107131 W CN 2020107131W WO 2021027659 A1 WO2021027659 A1 WO 2021027659A1
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lens
laser
spot
output
fiber
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PCT/CN2020/107131
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English (en)
French (fr)
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方强
方笑尘
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方强
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K26/00—Working by laser beam, e.g. welding, cutting or boring
    • B23K26/02—Positioning or observing the workpiece, e.g. with respect to the point of impact; Aligning, aiming or focusing the laser beam
    • B23K26/06—Shaping the laser beam, e.g. by masks or multi-focusing
    • B23K26/064—Shaping the laser beam, e.g. by masks or multi-focusing by means of optical elements, e.g. lenses, mirrors or prisms
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K26/00—Working by laser beam, e.g. welding, cutting or boring
    • B23K26/02—Positioning or observing the workpiece, e.g. with respect to the point of impact; Aligning, aiming or focusing the laser beam
    • B23K26/06—Shaping the laser beam, e.g. by masks or multi-focusing
    • B23K26/067—Dividing the beam into multiple beams, e.g. multifocusing
    • B23K26/0673—Dividing the beam into multiple beams, e.g. multifocusing into independently operating sub-beams, e.g. beam multiplexing to provide laser beams for several stations
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K26/00—Working by laser beam, e.g. welding, cutting or boring
    • B23K26/70—Auxiliary operations or equipment
    • B23K26/702—Auxiliary equipment

Definitions

  • the invention relates to a laser system and a processing head, in particular to a composite spot laser system based on multiple optical fiber output laser modules and a laser processing head using the system, which belongs to the field of laser processing technology and can be widely used in the laser processing industry .
  • Laser processing applications require laser spots with multiple structures to ensure the effect of laser processing.
  • For welding or cutting composite spot with high center power and low edge power see Figure 1-1A; for welding multi-spot spot, see Figure 1-1B and Figure 1-2; for cladding and welding , Quenched stripe spot, rectangular spot and circular ring spot, etc., see Figure 1-3.
  • the light spot shown in Figure 1-1A usually adopts a dual-wavelength light source.
  • the light path is shown in Figure 2-1.
  • the light of different wavelengths emitted by the two light sources L1 and L2 are collimated by collimating lenses CL-1 and CL-2, respectively.
  • the beams are combined by the multiplexer WC and the same focusing lens forms a superimposed spot on the focal plane.
  • another way to achieve the light spot shown in Figure 1-1A is to use a bifocal focusing lens.
  • the center area and edge area of the lens have different radii of curvature.
  • One lens forms two focal lengths.
  • the light output by the optical fiber passes through the collimating lens.
  • FIG. 1-1A With this bifocal lens, two focal points are formed along the axial direction, and the distribution of Fig. 1-1A is produced on the vertical optical axis section.
  • the light spot shown in Figure 1-1B can be used in welding to reduce metal sputtering.
  • Coherent's Finnish factory has developed a FL-ARM technology, which consists of a ring laser beam combiner and a center core and a The ring core is composed of special optical fibers, the central core of the optical fiber outputs a central spot, and the ring core outputs an annular spot.
  • the optical path of the three-spot spot shown in Figure 1-2 is shown in Figure 2-2A.
  • the light output by a certain fiber light source L is collimated by the collimating lens CL, and then split by the optical beam splitter BS in the parallel optical path.
  • the size of the divided area determines the power of each light spot size.
  • Figure 2-2B shows a schematic diagram of a possible setup of the beam splitter and lens array. Only one lens is set in the largest area to form the main spot, and BS1, LA1 and BS2 are set in the other two areas. LA2, produces the two auxiliary light spots needed.
  • the beam splitter that produces the deflection is usually an optical wedge.
  • the strip, rectangular and circular light spots shown in Figure 1-3 can be realized by the light path shown in Figure 2-3.
  • the lens After the light output by a certain fiber light source L is collimated by the collimating lens CL, the lens is converged in the parallel light path A lens array LA is arranged near the front focal plane of the lens, and the focusing lens FC converges to the back focal plane.
  • the above-mentioned spot technologies are all realized by using one or two light sources of different wavelengths, which are expensive high-power light sources. In reality, these light sources are usually obtained by combining low-power light sources. Therefore, the generation of laser processing spots can be regarded as achieved through the following path: multiple low-power laser modules + beam combiner + laser optical system. That is, the low-power laser turns into a high-power laser through beam combination, and then the high-power laser spot is transformed into the required spot through the optical system.
  • High-power beam combiners are very expensive.
  • the unit power price of high-power lasers is usually about twice the unit power price of low-power laser modules;
  • the generation of composite spots requires lens arrays, special fibers, etc.
  • Special optical components currently only a few companies in the world can produce these components, which are difficult to process and expensive.
  • the current technical solution cannot fully meet the higher requirements of laser processing for laser equipment: According to the current technical solution, once the system is designed and finalized, the spot structure is fixed in practical applications, that is, the spot distribution area is fixed and The relative energy distribution in different areas is fixed. Because different materials and applications in different scenarios have extremely different requirements for light spots, this makes the adaptability of traditional equipment poor. Users need to purchase a large number of equipment to meet different needs, which greatly increases costs.
  • the purpose of the present invention is to provide a composite spot laser system and processing head based on multiple optical fiber output laser modules, which directly use multiple low-power light sources to generate composite spots through an optical system, and Use this laser system to manufacture processing heads.
  • a composite spot laser system based on multiple optical fiber output laser modules characterized in that it includes multiple optical fiber output laser modules, multiple collimating lenses corresponding to the optical fiber output laser modules, and a focusing lens; the optical fiber output laser module The end face of the output fiber is located near the front focus of the corresponding collimating lens, the collimating lens includes at least one lens; the focusing lens includes at least one lens, located behind the collimating lenses; each fiber output laser module After passing the corresponding collimating lens on the end face of the output fiber, the focusing lens condenses the image to the vicinity of the back focus, and these image points are combined to form a composite spot.
  • the optical axes of the collimating lenses are parallel and arranged in parallel in space; the optical axis of the focusing lens is parallel to the optical axis of the collimating lens; the cross-sectional shape of the core of the output fiber of the optical fiber output laser module is circular or Rectangle.
  • the end faces of the output fibers of the fiber output laser module pass through the corresponding collimating lens and the focusing lens and then are at the focal plane.
  • the nearby images are superimposed to form a single spot with the same intensity in the spot area; or the middle power in the spot area is high, and the edge power is low.
  • the end faces of the output fibers of the fiber output laser module pass through the corresponding collimating lens and the focusing lens and then are at the focal plane.
  • the nearby images are arranged in a strip of light spots, or arranged in a rectangular light spot.
  • the end faces of the output fibers of the fiber output laser module pass through the corresponding collimating lens and the focusing lens and then are at the focal plane.
  • the nearby images form light spots distributed in several separate areas.
  • the end faces of the output fibers of the fiber output laser module pass through the corresponding collimating lens and the focusing lens and then are at the focal plane.
  • the images formed nearby form light spots arranged along the optical axis of the lens.
  • the end faces of the output fibers of the fiber output laser module pass through the corresponding collimating lens and the focusing lens and then at the focal plane
  • the nearby image forms a light spot with a ring structure; or a light spot consisting of a light spot with a ring structure and a point-shaped light spot at the center of the ring light spot.
  • the relative duration of light emission of the fiber output laser modules is the same or different; the relative duration of light emission power of each fiber output laser module is the same or different; the light emission of the fiber output laser modules
  • the relative duration is synchronous or asynchronous; a spot structure whose spot shape changes with time is formed to meet the requirements of different laser processing spots.
  • the invention also provides a laser processing head based on the composite spot laser system, which includes a plurality of fiber output laser modules, a plurality of collimating lenses corresponding to the fiber output laser modules, a focusing lens, a fiber holder, a collimating lens holder, Focusing lens holder and tubular housing.
  • the output ends of the output fibers of the multiple optical fiber output laser modules are fixed on the optical fiber holder; the multiple collimating lenses are fixed on the collimating lens holder; the focusing lens is fixed on the focusing lens holder;
  • the optical fiber holder is fixed inside the tubular housing close to one end, and the output end face of the optical fiber faces the other end of the tubular housing;
  • the collimating lens holder is arranged inside the tubular housing and adjacent to the optical fiber holder;
  • the focusing lens holder is fixed inside the tubular housing and adjacent to the collimating lens group holder; the light emitted from the end faces of the output fibers of the optical fiber output laser modules fixed on the fiber holder passes through the collimating lens.
  • At least one surface of at least one of the lenses in the focusing lens is attached to a corresponding lens frame with the same surface shape processed by a good thermally conductive material on the focusing lens holder, and the lens frame is attached to the collimated light
  • the corresponding area is hollowed out to allow the corresponding beam to pass through; this lens mounting structure can greatly increase the heat dissipation capacity of the lens.
  • the present invention has at least the following beneficial effects: 1.
  • the technical solution of the present invention greatly reduces the difficulty of handling thermal problems: 1) It avoids the use of high-power laser beam combiners, and the laser output is dispersed in many areas. At this point, heat concentration is avoided, and reliability problems caused by the beam combiner are avoided; 2)
  • the thermal problem in the laser optical system can be greatly eliminated by technical means; by dispersing the heat problem and taking heat conduction measures, you can The thermal effect is greatly reduced, and the system reliability and characteristics are improved; 2.
  • the technical solution of the present invention improves the beam quality. Under the same power and spot size conditions, the numerical aperture of the lens can be reduced, the number of lenses is reduced, and the thermal effect of the system is further reduced .
  • the present invention avoids the use of a beam combiner, which reduces the system cost; while in the laser optical system, all conventional optical elements are used, which can greatly reduce the cost of the laser optical system and improve system reliability; and, the present invention can Reduce the cost of the composite spot laser processing system.
  • the laser spot generated by the laser system of the present invention has the ability to adjust the spot structure in real time, provides the ability to change the spot structure in real time that cannot be achieved in the prior art, increases the flexibility and applicability of the equipment, and saves the user's equipment purchase cost.
  • Figure 1-1A is a schematic diagram of the cross-sectional energy distribution of the spot with high center power and low edge power.
  • Figure 1-1B is a schematic diagram of the cross-sectional energy distribution of a composite spot composed of an annular spot and a point spot located in the center of the annular spot.
  • Figures 1-2A and 1-2B are schematic diagrams of the multi-spot structure for welding or cutting, respectively.
  • Figures 1-3A, 1-3B, and 1-3C are schematic diagrams of strip, rectangular and circular light spots used for cladding, welding and laser heat treatment, respectively.
  • Figure 2-1 is a schematic diagram of the optical path structure for realizing the spot shown in Figure 1-1A.
  • Fig. 2-2A is an optical path diagram for realizing the spot structure shown in Fig. 1-2;
  • Fig. 2-2B is a schematic diagram of the optical path deflection devices located on the three areas on the front focal plane of the optical path focusing lens shown in Fig. 2-2A.
  • Fig. 2-3 is a schematic diagram of the light path that generates the light spot shown in Fig. 1-3, and a micro lens array is arranged near the focal plane in front of the focusing lens.
  • FIG. 3 is a schematic diagram of the optical path structure of the composite spot laser system based on multiple optical fiber output laser modules proposed by the present invention.
  • 4A is an arrangement structure of the collimating lens and the focusing lens when a system composed of 7 collimating lenses is viewed along the optical axis in the composite spot laser system technical solution based on multiple optical fiber output laser modules according to the present invention .
  • Fig. 4B is a schematic diagram of a strip light spot structure generated by the technical scheme of Fig. 4A.
  • Fig. 4C is a schematic diagram of a structure of three separated light spots generated by the technical scheme of Fig. 4A.
  • 5A is an arrangement structure of a collimating lens and a focusing lens when a system composed of 6 collimating lenses is viewed along the optical axis in the composite spot laser system technical solution based on multiple optical fiber output laser modules according to the present invention .
  • FIG. 5B is a schematic diagram of a rectangular light spot structure generated by the technical solution of FIG. 5A.
  • 6A is an arrangement structure of the collimating lens and the focusing lens when the system composed of 4 collimating lenses is observed along the optical axis direction according to the technical solution of the composite spot laser system based on multiple optical fiber output laser modules according to the present invention .
  • FIG. 6B is a schematic diagram of a ring-shaped spot structure generated by the technical solution of FIG. 6A.
  • Fig. 6C is a schematic diagram of a rectangular ring-shaped light spot structure generated by the technical scheme of Fig. 6A.
  • FIG. 6D is a schematic diagram of the structure of a center point spot of an edge ring light spot generated by the technical solution of FIG. 6A.
  • FIG. 7 is an arrangement structure of a collimating lens and a focusing lens when a system composed of 6 collimating lenses is viewed along the optical axis in the composite spot laser system technical solution based on multiple optical fiber output laser modules according to the present invention .
  • FIG. 8 is a schematic structural diagram of a laser processing head system proposed by the present invention using a composite spot laser system based on multiple optical fiber output laser modules proposed by the present invention.
  • FIG. 9A is a schematic diagram of a focusing lens
  • FIG. 9B is a side view of the structure of the lens bonding part in a focusing lens frame made of a good thermal conductor and bonded with the lens shown in FIG. 9A; Shows a front schematic view of the structure of the lens-fitting part in a focusing lens frame made of a good thermal conductor in which the lenses are bonded together;
  • L, L1 and L2 represent lasers respectively; CL, CL-1, CL-2,..., and CL-M represent collimating lenses respectively; FL represents focusing lens, FL-1 represents a certain lens of focusing lens; BS , BS-1, BS-2 respectively represent the optical splitter; WC represents the multiplexer; LA, LA0, LA1, LA2 respectively represent the micro lens array; M-1, M-2,..., MN respectively represent the optical fiber output laser module.
  • GXJ stands for fiber holder;
  • CLZJ stands for collimating lens group holder; FLZJ stands for focusing lens holder, FLJ-1A stands for a certain part of a lens holder on the focusing lens holder;
  • GZK stands for tubular housing.
  • FIG. 3 is a schematic diagram of the optical path structure of the composite spot laser processing head based on multiple optical fiber output modules proposed by the present invention. It is composed of N fiber output laser modules, M collimating lenses and a focusing lens. Among them: M is less than or equal to N, that is, the number of collimating lenses is less than or equal to the number of fiber output laser modules, N fiber output modules M-1, M-2, ..., MN are divided into M groups, and each group corresponds to M collimating lenses CL- 1.
  • the end surface of the output fiber of each group of fiber output laser module is located near the front focal plane of the corresponding collimating lens; the focusing lens FL is located behind the M collimating lenses; After the light output by the N optical fiber output laser module passes through the corresponding collimating lens, it is imaged by the focusing lens to the vicinity of the back focal plane to form a composite spot.
  • the collimating lens CL-1, CL-2,..., and The parameters of CL-M and the parameters of the focusing lens FL can facilitate the design of laser spots with various structures.
  • the optical axes of the M collimating lenses are generally parallel and parallel to the optical axis of the focusing lens FL.
  • the shape of the output fiber cores of the fiber output laser modules M-1, M-2, ..., M-N can be circular or rectangular.
  • the position of the output fiber end face of the fiber output laser modules M-1, M-2,..., MN, the shape and parameters of the fiber core, and the collimating lens CL-1, CL-2,... , And CL-M parameters and the parameters of the focusing lens FL can overlap the images formed by the output fiber end faces of all fiber output laser modules near the back focal plane of the focusing lens FL to form a composite spot.
  • the image size of the fiber end face corresponding to each collimating lens can be the same or different; when the image size is different, a spot structure with high power in the middle region and low power in the edge region can be formed.
  • the position of the output fiber end face of the fiber output laser modules M-1, M-2,..., MN, the collimating lens CL-1, CL-2,..., and CL-M parameters can be adjusted by adjusting And the parameters of the focusing lens, the images of the output fiber end faces of all fiber output laser modules are arranged into a strip spot on the back focal plane of the focusing lens FL.
  • the position of the output fiber end face of the fiber output laser modules M-1, M-2,..., MN, the collimating lens CL-1, CL-2,..., and CL-M parameters can be adjusted by adjusting And the parameters of the focusing lens, the images of the output fiber end faces of all fiber output modules are arranged into a rectangular spot on the back focal plane of the focusing lens FL.
  • the position of the output fiber end face of the fiber output laser modules M-1, M-2,..., MN, the collimating lens CL-1, CL-2,..., and CL-M parameters can be adjusted by adjusting And the parameters of the focusing lens, the images of the output fiber end faces of all the fiber output laser modules are arranged on the back focal plane of the focusing lens FL into a spot distributed on multiple separated areas.
  • the position of the output fiber end face of the fiber output laser modules M-1, M-2,..., MN, the collimating lens CL-1, CL-2,..., and CL-M parameters can be adjusted by adjusting And the parameters of the focusing lens FL, so that the images formed by the output fiber end faces of all the fiber output laser modules near the back focal plane of the focusing lens FL are arranged into multiple points along the optical axis direction.
  • the position of the output fiber end face of the fiber output laser modules M-1, M-2,..., MN, the collimating lens CL-1, CL-2,..., and CL-M parameters can be adjusted by adjusting And the parameters of the focusing lens FL, so that the images formed by the output fiber end faces of all fiber output laser modules near the back focal plane of the focusing lens FL are arranged in a ring structure, which can be a circular ring structure or a rectangular ring structure.
  • the position of the output fiber end face of the fiber output laser modules M-1, M-2,..., MN, the collimating lens CL-1, CL-2,..., and CL-M parameters can be adjusted by adjusting And the parameters of the focusing lens FL, so that the images formed by the end faces of the output fibers of all the optical fiber output laser modules near the back focal plane of the focusing lens FL are arranged into an edge ring-shaped center point spot structure.
  • the optical fiber output laser modules can be continuous light laser modules, quasi continuous light laser modules or pulsed laser modules. That is, the relative duration of light emission of the fiber output laser modules can be the same or different; the relative duration of light emission of each fiber output laser module can be the same or different; the optical fibers The relative duration of the output laser module's light emission can be synchronous or asynchronous; by controlling the light emission rules of the modules, a light spot structure whose light spot shape changes with time can be formed to meet the requirements of different laser processing for light spots.
  • FIG. 8 is a schematic structural diagram of a laser processing head system proposed by the present invention using a composite spot laser system based on multiple optical fiber output laser modules proposed by the present invention.
  • a laser processing head system proposed by the present invention using a composite spot laser system based on multiple optical fiber output laser modules proposed by the present invention.
  • multiple fiber output laser modules M-1, M-2,..., MN multiple collimating lenses CL-1, CL-2,..., and CL-M corresponding to the fiber output laser module, and a focusing lens FL , Fiber holder GXJ, collimating lens holder ZZZJ, focusing lens holder FLZJ and tubular housing GZK.
  • the output ends of the output fibers of the multiple fiber output laser modules M-1, M-2,..., MN are fixed on the fiber support GXJ; multiple collimating lenses CL-1, CL-2,..., and CL- M is fixed on the collimating lens holder ZZZJ; the focusing lens FL is fixed on the focusing lens holder FLZJ; the fiber holder GXJ is fixed inside the tubular housing GZK near one end, and the fiber output end face faces the other end of the tubular housing GZK One end; the collimating lens holder ZZZJ is arranged inside the tubular housing GZK and adjacent to the fiber holder GXJ; the focusing lens holder FLZJ is fixed inside the tubular housing and adjacent to the collimating lens group holder ZZZJ; the optical fibers are fixed on the fiber holder GXJ The light emitted from the output fiber end face of the output laser module passes through the corresponding collimating lens fixed on the collimating lens group bracket ZZZJ and the focusing lens fixed on
  • the laser head technical solution can theoretically form laser processing spots of various structures, and can make these spots have the ability to change the spot structure in real time.
  • the laser processing head at least one surface of at least one lens of the lenses in the focusing lens is attached to the corresponding lens frame on the focusing lens holder with the same surface shape processed by a good thermally conductive material,
  • the area corresponding to the collimated light on the lens frame is hollowed out to allow the corresponding beam to pass through.
  • the focusing lens is usually composed of multiple lenses. In order to make each lens can dissipate heat well, it is necessary to make the two sides of each lens as far as possible to leave a light channel
  • the heat-conducting plate is attached, and a certain gap is designed between each lens to increase the heat dissipation capacity of the heat-conducting plate.
  • Figure 9 shows a schematic diagram of this lens mounting structure:
  • Figure 9A is a schematic diagram of a certain lens FL-1 in the focusing lens;
  • Figure 9B is a partial structure FLJ-1A of the lens frame corresponding to a certain surface of the lens of Figure 9A
  • Figure 9C is a schematic diagram of the front structure of a part of the lens frame FLJ-1A corresponding to a certain surface of the lens of Figure 9A. Its surface corresponding to the lens surface has the same shape as the lens, and the two are attached to At the same time, a through hole is opened in the lens frame corresponding to the light-transmitting part of the lens to allow light to pass through.
  • the material of the lens frame is a good thermal conductivity material, usually copper or aluminum is used for processing.
  • the laser processing head technical solution has the following advantages compared with the existing technical solutions in thermal management: 1. Avoid the use of beam combiners, technically avoid the problem of heat concentration, and the leakage light generated by the laser module output point is dispersed in the M Before a collimating lens, the amount of heat leakage at each point is greatly reduced; 2. Using M collimating lenses, the size of the lens is much smaller than the lens used in the prior art. For a poor thermal conductor such as glass, the lens diameter is small and cooling The path is short, the heat dissipation effect is good, the lens diameter is small, the lens is thin, and the thermal effect is small; 3.
  • the focusing lens is similar to the traditional lens, but because the laser beam is a plurality of spatially separated beams, it is wrapped with a hollow heat conduction plate made of a good heat conductor Covering the surface of each lens in the focusing lens, the hollow corresponding to the laser beam from the collimator lens, because the thermal conductivity of a good thermal conductor is tens to hundreds of times that of glass, this solution can greatly improve the cooling effect of the lens, so that The thermal effect of the lens can be ignored.
  • Embodiment 1 According to the technical solution of the laser system based on multiple optical fiber output laser modules proposed in the present invention, in an embodiment of the present invention, it is necessary to realize the structure of light synthesis of 49 optical fiber output laser modules into one light spot, and the light spot is required 1.8 mm in diameter.
  • the system adopts the structure of 7 collimating lenses and 1 focusing lens shown in Figure 4A.
  • the optical axes of the 7 collimating lenses are parallel, the focal lengths of the 7 collimating lenses are the same, and the front focal planes coincide, the light of the focusing lens FL
  • the axis is parallel to the optical axis of the collimating lens and coincides with the optical axis of the collimating lens in the center;
  • the output power of the semiconductor laser module with a wavelength of 915 nm is 120 watts, the output fiber core diameter is 105 microns, and the cladding diameter is 125 Micron, with a numerical aperture of 0.22.
  • 49 laser modules are divided into 7 groups, 7 in each group, the end faces of the 7 output fibers are aligned, and 6 are arranged together in a structure surrounding one, and the end faces of each group of fibers are located in the corresponding collimating lens
  • the focal point of the collimator lens is 30 mm, and the focal length of the focusing lens is 150 mm.
  • the end faces of each group of optical fibers form a spot with a diameter of 1.8 mm at the focal point behind the focusing lens.
  • the laser system can be used in fields such as laser welding, cladding and 3D printing.
  • Embodiment 2 According to the technical solution of the laser system based on multiple optical fiber output laser modules proposed in the present invention, in an embodiment of the present invention, a high-power spot in the center area and low-power in the edge area is required, as shown in FIG. 4A
  • the core diameter of the output fiber of each module is 20 microns, the numerical aperture is 0.06, and the fiber cladding diameter is 400 Micrometers.
  • 6 have a focal length of 50 mm, one has a focal length of 25 mm, a lens pitch is 8 mm, and a focusing lens has a focal length of 500 mm.
  • the cutting spot formed by this system is a superposition of a high-power spot with a diameter of 200 microns and a low-power spot with a diameter of 400 microns.
  • the numerical aperture of the high-power spot is about 0.046.
  • the system can be used for laser cutting, and is especially suitable for cutting high-reflectivity metals. Because according to the nature of the metal, the reflection of the metal surface will be greatly reduced with the increase of temperature, the low-power spot in this system can preheat the high-power cutting area, which greatly suppresses the reflectivity of the metal and protects the laser system.
  • the six laser modules that form a 200-micron spot are uniformly controlled, and one laser module that forms a 400-micron spot is individually controlled, and the power distribution of the spot can be flexibly changed according to actual processing requirements to meet different processing requirements. Claim.
  • Embodiment 3 According to the technical solution of the laser system based on multiple optical fiber output laser modules proposed in the present invention, in an embodiment of the present invention, a spot with a sheet-shaped converging structure is required, and the collimating lens and the converging lens in the optical path Using the structure shown in Figure 7, the six lenses are arranged in one plane in one dimension, the optical axes of the six lenses are parallel, the focal lengths of the six lenses are the same, and the front focal planes coincide, the optical axis of the focusing lens FL is the same as that of the collimating lens. The optical axis is parallel, and the distribution center of the 6 collimating lenses coincides with the optical axis of the focusing lens.
  • the 6 fiber output laser modules are fiber lasers with a wavelength of 1064 nanometers and a power of 500 to 1000 watts.
  • the core diameter of the output fiber of each module is 20 microns, the numerical aperture is 0.06, and the fiber cladding diameter is 400 microns.
  • the collimating lens has a focal length of 50 mm, a lens pitch of 8 mm, and a focusing lens of 500 mm.
  • the diameter of the cutting spot formed by this system is 200 microns, the numerical aperture of the convergent beam in the narrow direction is 0.006, and the numerical aperture of the convergent spot in the wide direction is about 0.046.
  • This laser system has excellent beam quality and is suitable for cutting thick plates with a large radius of curvature, and will obtain good cutting quality and high cutting efficiency.
  • Embodiment 4 According to the technical solution of the laser system based on multiple optical fiber output laser modules proposed in the present invention, in an embodiment of the present invention, a spot needs to be formed at two points along the axis, and the distance between the two spots is 10 mm, the spot size is 1.8 mm.
  • This embodiment uses 49 optical fibers with a wavelength of 976 nanometers to output a semiconductor laser module, with an output power of 120 watts, an output fiber core diameter of 105 microns, a cladding diameter of 125 microns, and a numerical aperture of 0.22.
  • the system uses the 7 collimating lenses and 1 focusing lens structure shown in Figure 4A.
  • the optical axes of the 7 collimating lenses are parallel, and the optical axis of the focusing lens FL is parallel to the optical axis of the collimating lens and is in the center.
  • the optical axes of the collimating lenses coincide; the focal lengths of the 7 collimating lenses are the same, 30 mm, and the focal length of the focusing lens is 150 mm.
  • 49 laser modules are divided into 7 groups, 7 in each group, 7 output fiber end faces are aligned, and 6 laser modules are arranged together in a structure surrounding one.
  • each group of optical fibers are located near the focal point of the corresponding collimating lens; the 6 groups of end faces located at the edge are divided into two alternately arranged two groups, by adjusting 3 of one group and the end face of the central group in front of the collimating lens
  • the position of the image is 5 mm on the optical axis of the rear focus of the focusing lens; by adjusting the position of another group of 3 end faces near the front focus of the collimator lens, the image is imaged on the optical axis of the rear focus of the focusing lens 5 Millimeters.
  • This kind of spot it is possible to obtain a spot structure with high power at the center and low power at the edge at the positions near the two image points, and the power distribution can vary with the position.
  • the laser system can be used in fields such as laser welding, cladding and 3D printing.
  • Embodiment 5 According to the technical solution of the laser system based on multiple optical fiber output laser modules proposed in the present invention, in an embodiment of the present invention, it is required to realize the spot structure shown in FIG. 4B, which is a strip with a ratio of length and width of 7:1. Shaped spot.
  • the collimating lens adopts the structure shown in FIG. 4A, the optical axes of the 7 lenses are parallel, the focal lengths of the 7 lenses are the same, and the front focal planes coincide, the optical axis of the focusing lens FL is the same as the optical axis of the collimating lens Parallel and coincide with the optical axis of the collimator lens located in the center.
  • the fiber cores of the output fibers of the 7 fiber output modules adopt a square structure, and the fiber end faces are located on the front focal plane of the corresponding collimating lens, and the corresponding sides of each fiber core are arranged in parallel.
  • D represents the fiber side
  • D represents the fiber side
  • the distances of the end faces of the 7 fibers from the focal point in the direction parallel to a certain edge of the fiber core to 3D, 2D, D, 0, -D, -2D, and -3D.
  • the light distribution shown in Fig. 4B is obtained on the focal plane. This light spot is widely used in the fields of laser heat treatment and laser cladding.
  • Embodiment 6 According to the technical solution of the laser system based on multiple optical fiber output laser modules proposed by the present invention, in an embodiment of the present invention, it is required to realize the spot structure shown in FIG. 4C, which is a square spot and two circular spots. Composite light spot composed of light spots.
  • the collimating lens adopts the structure shown in FIG. 4A, seven lenses are arranged in the same plane, their optical axes are parallel, and the optical axis of the focusing lens FL is parallel to the optical axis of the collimating lens, and is located at The optical axes of the collimating lens in the center coincide.
  • the focal length of 5 of the 7 lenses is f1
  • the focal length of 2 lenses is f2
  • the core of the output fiber of the optical fiber output module corresponding to the 5 lenses with focal length f1 adopts a square structure.
  • the center of the fiber end is located on the front focal plane of the corresponding collimating lens, and the corresponding sides of each fiber core are arranged in parallel.
  • the fiber cores of the output fiber of the fiber output module corresponding to the two focal length f2 lenses adopt a circular structure, and the fiber centers are respectively If the focus is deviated in two directions within the focal plane, the light distribution shown in FIG. 4C can be obtained on the back focal plane of the converging lens.
  • parameters such as the wavelength of the light wave, the size of the fiber core, and the focal length of the lens can be flexibly set, which increases design flexibility. This light spot is widely used in the field of laser welding.
  • the five laser modules corresponding to the square spot are uniformly controlled, and the modules corresponding to the two circular spots are uniformly controlled.
  • the power distribution of the square spot and the round spot can be controlled to meet the requirements of different laser processing technologies. Claim.
  • Embodiment 7 According to the technical solution of the laser system based on multiple optical fiber output laser modules proposed by the present invention, in an embodiment of the present invention, it is required to realize the spot structure shown in FIG. 5B, which is a rectangular spot.
  • the collimating lens adopts the structure shown in FIG. 5A, the 6 lenses are located on the same plane and the optical axes are parallel, the focal lengths of the 6 lenses are the same, the optical axis of the focusing lens FL is parallel to the optical axis of the collimating lens, The distribution center of the 6 lenses coincides with the optical axis of the focusing lens.
  • the fiber cores of the output fibers of the 6 fiber output modules adopt a square structure, and the fiber end faces are located on the front focal plane of the corresponding collimating lens, and the corresponding sides of each fiber core are arranged in parallel.
  • D represents the fiber side
  • the length of the 4 fiber end faces is set in (-D,D/2), (0,D/2), (D,D/2), (-D) in a coordinate system set parallel to the direction of the fiber core ,-D/2), (0,-D/2) and (D,-D/2)
  • the light distribution shown in Fig. 5B can be obtained on the back focal plane of the converging lens. This light spot is widely used in the field of laser heat treatment.
  • Embodiment 8 According to the technical solution of the laser system based on multiple optical fiber output laser modules proposed in the present invention, in an embodiment of the present invention, it is required to realize the circular spot shown in FIG. 6B, the diameter of the circular spot is 16 mm, 2.1 mm ring.
  • the collimating lens and focusing lens of the laser system adopt the structure shown in FIG. 6A.
  • the optical axes of the four collimating lenses are parallel, and the optical axis of the focusing lens FL is parallel to the optical axis of the collimating lens, and is located at the center of symmetry of the optical axes of the four collimating lenses.
  • the designed set of parameters is: 48 wavelengths of 915 fiber output semiconductor laser module output power is 120 watts, output fiber core diameter 105 microns, cladding diameter 125 microns, numerical aperture 0.22; these 48 modules are divided into 12 One group, the end faces of the output fibers are aligned, and the fiber axes are arranged on a circle with a diameter of 800 microns at equal angular intervals; the collimating lens has a focal length of 20 mm, and the focusing lens has a focal length of 400 mm.
  • each group of fibers can be formed into a continuous ring of 16 mm diameter fiber end faces on the back focal plane of the focusing lens.
  • the fiber image distance is shifted by one-half of the circumferential direction to form a circular laser spot with high uniformity.
  • the system can be used for laser welding of circular welds.
  • Embodiment 9 According to the technical solution of the laser system based on multiple optical fiber output laser modules proposed in the present invention, in an embodiment of the present invention, it is required to realize the rectangular ring spot shown in FIG. 6C, and the size of the rectangular ring laser spot is 13.75 mm X 11.25, the spot width is about 1 mm.
  • the collimating lens and focusing lens of the laser system adopt the structure shown in FIG. 6A.
  • the optical axes of the four collimating lenses are parallel, and the optical axis of the focusing lens FL is parallel to the optical axis of the collimating lens, and is located at the center of symmetry of the optical axes of the four collimating lenses.
  • the designed set of parameters is: 40 wavelengths of 915 fiber output semiconductor laser module output power is 120 watts, output fiber core diameter 105 microns, cladding diameter 125 microns, numerical aperture 0.22; these 42 modules are divided into 4 groups , There are 12 in each of two groups and 8 in each of the other two groups; the end faces of the output fibers are aligned and arranged along a straight line at a distance of 125 microns; the focal length of the collimating lens is 20 mm, and the focal length of the focusing lens is 200 mm.
  • the four groups of fibers can form a 13.75 mm X 11.25 rectangular ring laser spot on the back focal plane of the focusing lens, with a line width of about 1.05 mm.
  • the system can be used for laser welding of rectangular ring welds.
  • Embodiment 10 According to the technical solution of a laser system based on multiple optical fiber output laser modules proposed in the present invention, in an embodiment of the present invention, it is required to realize the spot shown in FIG. 6D, that is, a point-shaped spot in the center and surrounding the spot For a ring spot of, the center spot diameter is 2 mm, the outer diameter of the ring edge spot is 6 mm, and the ring width is 1 mm.
  • the collimating lens and focusing lens of the laser system adopt the structure shown in FIG. 6A.
  • the optical axes of the four collimating lenses are parallel, and the optical axis of the focusing lens FL is parallel to the optical axis of the collimating lens, and is located at the center of symmetry of the optical axes of the four collimating lenses.
  • a set of designed parameters is set as follows: 24 wavelengths of 915 fiber output semiconductor laser module output power is 120 watts, output fiber core diameter 105 microns, cladding diameter 125 microns, numerical aperture 0.22; 2 wavelengths of 1064 microns fiber Laser module, output power 1000 watts, output fiber core diameter 100 microns, numerical aperture 0.1.
  • 24 semiconductor laser modules are divided into two groups, 12 in each group, the end faces of the output fibers are aligned, the fiber axes are arranged on a circle with a diameter of 500 microns at equal angular intervals, and the focal length of the corresponding collimating lens is 20 mm, and the focusing lens The focal length is 200 mm; by adjusting the position of the end face of each group of fibers at the front focal point of the collimating lens, each group of fibers can be formed into a continuous ring of 5 mm diameter fiber end faces on the back focal plane of the focusing lens, and the two The ring is offset by one-half of the fiber image distance in the circumferential direction, which can form a highly uniform circular laser spot; the focal length of the collimating lens corresponding to the two fiber laser modules is 10 mm, by adjusting the end face of each fiber At the position of the front focal point of the collimating lens, a 2 mm diameter spot formed by two optical fibers can be superimposed on the rear focal plane of
  • the laser modules corresponding to the ring-shaped spot are uniformly controlled, and the modules corresponding to the central point-shaped spot are uniformly controlled, and the power distribution in different regions can be controlled to meet the requirements of different laser processing technologies.
  • Embodiment 11 According to the technical solution of the laser processing head of the laser system based on multiple optical fiber output laser modules proposed in the present invention, a certain embodiment of the present invention requires a laser processing head.
  • the light spot has a structure with high center power and low edge area.
  • the laser system adopts the structure of 7 collimating lenses and 1 focusing lens shown in Fig. 4A, and the laser head adopts the structure shown in Fig.
  • the collimating lens is fixed on the collimating lens holder; the focusing lens is fixed on the focusing lens holder; the optical fiber holder is fixed inside the tubular housing near one end, and the optical fiber output end face faces the other end of the tubular housing One end; the collimating lens holder is arranged inside the tubular housing and adjacent to the optical fiber holder; the focusing lens holder is fixed inside the tubular housing and adjacent to the collimating lens group holder; the optical fibers fixed on the optical fiber holder output the output fibers of the laser module
  • the light emitted from the end face passes through the corresponding collimator lens fixed on the collimator lens group holder, and after passing through the focusing lens fixed on the focusing lens holder, the required composite laser spot is generated.
  • the relevant technical parameters of the optical part are: the optical axes of the 7 collimating lenses are parallel, the focal lengths of the 7 collimating lenses are the same, and the front focal planes coincide, the optical axis of the focusing lens FL is the same as that of the collimating lens
  • the optical axis is parallel and coincides with the optical axis of the collimating lens located in the center;
  • the 7 fiber output laser modules are fiber lasers with a wavelength of 1064 nanometers, and the power is 500 to 1000 watts. Each module outputs the core of the fiber
  • the diameter is 20 microns, the numerical aperture is 0.06, and the fiber cladding diameter is 400 microns.
  • 6 have a focal length of 50 mm, one has a focal length of 25 mm, a lens pitch is 8 mm, and a focusing lens has a focal length of 500 mm.
  • the cutting spot formed by the system is a superposition of a high-power spot with a diameter of 200 microns and a low-power spot with a diameter of 400 microns.
  • the 200-micron spot is superimposed by the output light of 6 laser modules, and the 400-micron diameter spot is generated by one module.
  • the numerical aperture of the high-power spot is about 0.046.
  • the fiber holder GXJ is a cylinder with a diameter of 30 mm, a through hole is opened on the central axis of the cylinder, and it is uniform on a circle with a diameter of 16 mm centered on the central axis of the cylinder.
  • the collimating lens holder ZZZJ is a 30 mm diameter disc, and a 7.2 mm diameter through hole is opened on the central axis of the disc, and a 16 mm diameter circle is centered on the central axis of the disc.
  • the focusing lens holder FLZJ is a circular ring with an outer diameter of 30 mm and an inner diameter of 26 mm;
  • the inner hole of the tubular housing GZK is a circular hole with a diameter of 30 mm.
  • the output fibers of the 7 fiber output laser modules are arranged in the 7 holes of the cylindrical fiber holder; the 7 collimating lenses are arranged in the 7 holes of the disc-shaped collimating lens holder ZZZJ; the focusing lens is arranged in In the inner hole of the ring-shaped focusing lens holder FLZJ; the fiber holder GXJ is fixed to one end of the inner hole of the tubular housing GZK, and the collimating lens holder ZZZJ is fixed in the tubular housing GZK, adjacent to the fiber holder GXJ, the laser output on the fiber holder
  • the output fiber end face of the module corresponds to the collimating lens on the collimating lens holder and is located near the corresponding focal point; the focusing lens holder FLZJ is fixed in the tubular housing GZK, adjacent to the collimating lens holder ZZZJ.
  • the laser module with a wavelength of 1064 outputs the light emitted from the end face of the optical fiber.
  • a center power and low edge power are formed on the back focal plane of the focusing lens.
  • Laser spot which is suitable for laser cutting, especially for cutting high-reflectivity metals. Because according to the nature of the metal, the reflection of the metal surface will be greatly reduced with the increase of temperature, the low-power spot in this system can preheat the high-power cutting area, which greatly suppresses the reflectivity of the metal and protects the laser system.
  • the 500mm focal length focusing lens adopts two separate lenses to form an achromatic and spherical lens.
  • the lens facing the collimated light is a biconvex lens, the material is quartz glass, and the surface facing the collimated light
  • the radius of curvature distribution is 118.06, the radius of curvature of the other surface is 168.98, and the center thickness is 2 mm;
  • the other lens is a biconcave lens, the material is F2 glass, and the center distance of the first lens is 2 mm, facing the surface of the previous lens
  • the radius of curvature of is 160.54, and the radius of curvature of the other side is 760.12.
  • the outer surfaces of the two lenses are cooled using the structure shown in FIGS. 9A-9C.
  • the lens frame is made of red copper.
  • the lens frame corresponding to the biconvex lens facing the collimating surface is concave, with a radius of curvature of 118.06.
  • On a circle with a diameter of 16.02 centered on the vertex 6 holes with a diameter of 6.5 are uniformly opened, and a hole with a diameter of 6.5 is opened at the vertex.
  • the thickness of the frame is 8 mm.
  • the lens frame corresponding to the biconcave lens facing the working surface is convex, with a radius of curvature of 760.12.
  • the composite spot laser system based on multiple optical fiber output laser modules and the processing head using the system proposed in the present invention can provide various spots required for laser processing, and has the ability to change the spot structure in real time, which can meet various laser processing requirements. Requirements. Technically, the thermal problem in the system is better solved, making the system reliable and stable. Because of the direct use of low-power laser modules, the use of high-power lasers is avoided, while the use of conventional optical components reduces the cost of the laser processing system.

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Abstract

一种基于多个光纤输出激光模块的复合光斑激光系统，包括多个光纤输出激光模块、与光纤输出激光模块对应的多个准直透镜以及一个聚焦透镜；所述光纤输出激光模块的输出光纤端面位于与之对应的准直透镜的前方焦点附近，所述准直透镜至少包括一片透镜；所述聚焦透镜至少包括一片透镜，位于准直透镜后面。该激光系统避免了大功率激光合束器的使用，激光输出分散在多个点处，避免了热的集中和由合束器带来的可靠性问题；提高了光束质量；大幅降低热效应的影响，提高系统可靠性和特性。还涉及一种利用复合光斑激光系统的激光加工头。

Description

基于多个光纤输出激光模块的复合光斑激光系统及加工头 技术领域
本发明涉及一种激光系统及加工头，特别是一种基于多个光纤输出激光模块的复合光斑激光系统及利用该系统的激光加工头，属于激光加工技术领域，可广泛应用于激光加工产业中。
背景技术
激光加工应用中需要多种结构的激光光斑以保证激光加工的效果。比如：用于焊接或切割的中心功率大边缘功率小的复合光斑，参见图1-1A；用于焊接的多光点光斑，参见图1-1B和图1-2；用于熔覆、焊接、淬火的条状光斑、矩形光斑及圆环形光斑等，参见图1-3。
目前实现图1-1A所示光斑通常采用双波长光源，光路如图2-1所示，两个光源L1和L2发出的不同波长的光分别经准直透镜CL-1和CL-2准直后，用合波镜WC合束后由同一个聚焦镜在焦面上形成叠加的光斑。此外，实现图1-1A所示光斑还有一种办法是采用双焦距聚焦透镜，该透镜中心区域和边缘区域的曲率半径不同，在一个透镜形成两个焦距，由光纤输出的光经准直透镜和这种双焦距透镜后就沿轴向形成两个焦点，在垂直光轴截面上就产生图1-1A的分布。图1-1B所示光斑用在焊接中可以减少金属溅射，目前，相干公司芬兰工厂开发了一种FL-ARM技术，它由一种环形激光合束器和一种包含一个中心芯和一个环形芯的特种光纤组成，光纤的中心芯输出中心光斑，环形芯输出环状光斑。图1-2所示的3光点光斑的实现光路如图2-2A所示，某个光纤光源L输出的光经准直透镜CL准直后，在平行光路中由光分束器BS分割成3个区域，三个区域的光之间存在相对偏转并由透镜阵列LA整形和匀光，之后再聚焦透镜FC的后焦面上形成3个光点，所分割区域大小决定个光点功率大小。图2-2B给出了分束器和透镜阵列的一种可行设置的示意图，最大的区域上只设置一个透镜整列LA0，形成主光斑，在另两个区域上分别设置BS1、LA1和BS2、LA2，产生需要的两个辅助光斑。产 生偏转的分束镜通常是光楔。图1-3所示的条形、矩形和圆环形光斑，可由图2-3所示光路实现，某个光纤光源L输出的光由准直透镜CL准直后，在平行光路中汇聚透镜的前焦面附近设置有透镜阵列LA，然后由聚焦透镜FC汇聚到后焦面上。
上述的这些光斑技术都采用一个或两个不同波长光源实现的，这些光源都是昂贵的大功率光源。而现实中，这些光源通常都是采用小功率光源通过合束后得到的。因此，激光加工光斑的产生可以看成是通过下列路径实现的：多个小功率激光模块+合束器+激光光学系统。即小功率激光通过合束变成大功率激光，然后大功率激光光斑通过光学系统变换成所需光斑。
在上述这种技术路径中，存在以下问题：
首先是系统中的技术问题：1、激光在合束过程中，合束器必须处理掉合束过程中不可避免的泄漏光，热管理非常难，导致器件可靠性低；2、合束器的不完美，使光束质量严重偏离其理论可以达到的水平，为后续激光光学系统设计带来困难；3、激光光学系统在大功率激光作用下会吸收热量导致温度升高，由于玻璃是不良热导体，透镜只能通过透镜框在边缘冷却，这就导致透镜中心温度高，形成所谓的热透镜效应，功率越大，热透镜效应越明显，会产生光斑的漂移，影响加工质量。
其次是成本问题：1、大功率合束器非常贵，大功率激光器的单位功率价格通常是小功率激光模块的单位功率价格的2倍左右；2、复合光斑的产生需要透镜阵列、特种光纤等特殊的光学元件，目前这些元件在国际上只有少数几家公司可以生产，加工困难，价格昂贵。
最后，当前的技术方案尚不能完全满足激光加工对激光设备更高的特性要求：按照目前的技术方案，系统一旦设计定型后，在实际应用中光斑结构是固定的，也就是光斑分布区域固定及不同区域的相对能量分布固定，由于不同材料和不同场景的应用对光斑的要求差别极大，这就使得传统设备的适应性差，用户需要采购大量设备应对不同的需求，大幅增加成本。
发明内容
为了解决现有技术中存在的问题，本发明的目的是提供一种基于多个光纤输出激光模块的复合光斑激光系统及加工头，直接利用多个小功率光源，通过光学系统产生复合光斑，并利用这种激光系统制造加工头。
为了实现上述目的，本发明的技术方案概括如下：
一种基于多个光纤输出激光模块的复合光斑激光系统，其特征在于，包括多个光纤输出激光模块、与光纤输出激光模块对应的多个准直透镜以及一个聚焦透镜；所述光纤输出激光模块的输出光纤端面位于与之对应的准直透镜的前方焦点附近，所述准直透镜至少包括一片透镜；所述聚焦透镜至少包括一片透镜，位于诸准直透镜的后方；每一个光纤输出激光模块的输出光纤端面经与之相对应的准直透镜后，由聚焦透镜聚成像到后焦点附近，这些像点组合起来形成复合光斑。
所述诸准直透镜的光轴平行，在空间并行设置；聚焦透镜光轴与准直透镜光轴平行；所述光纤输出激光模块输出光纤的芯的横截面的形状是圆形的，或者是矩形的。
通过调整激光模块光纤输出端面位置、纤芯形状、纤芯尺寸及所对应准直透镜焦距，使诸所述光纤输出激光模块输出光纤端面通过对应的准直透镜及所述聚焦透镜后在焦面附近成的像叠加在一起形成一个单一的光斑，光斑区域的强度相同；或者光斑区域内中间功率高，边缘功率低。
通过调整激光模块光纤输出端面位置、纤芯形状、纤芯尺寸及所对应准直透镜焦距，使诸所述光纤输出激光模块输出光纤端面通过对应的准直透镜及所述聚焦透镜后在焦面附近成的像排成一条形光斑，或者排列成一个矩形光斑。
通过调整激光模块光纤输出端面位置、纤芯形状、纤芯尺寸及所对应准直透镜焦距，使诸所述光纤输出激光模块输出光纤端面通过对应的准直透镜及所述聚焦透镜后在焦面附近成的像形成分布在几个分离区域的光斑。
通过调整激光模块光纤输出端面位置、纤芯形状、纤芯尺寸及所对应准直透镜焦距，使诸所述光纤输出激光模块输出光纤端面通过对应的准直透镜及所述聚焦透镜后在焦面附近成的像形成沿透镜光轴方向排列的光斑。
通过调整激光模块光纤输出端面位置、纤芯形状、纤芯尺寸及所对应准直透镜焦距，使诸所述光纤输出激光模块输出光纤端面通过对应的准直透镜及所述聚焦透镜后在焦面附近成的像形成环状结构的光斑；或者形成由一个环状结构的光斑及一个位于环状光斑中心的点状光斑组成的光斑。
所述诸光纤输出激光模块发光的相对持续时间是相同的，或者是不同的；各光纤输出激光模块发光的相对持续时间内的功率是相同的，或者是不同的；诸光纤输出激光模块发光的相对持续时间是同步的，或者是不同步的；形成光斑形状随时间变化的光斑结构，满足不同激光加工对光斑的要求。
本发明还提供了一种基于复合光斑激光系统的激光加工头，包括多个光纤输出激光模块、与光纤输出激光模块对应的多个准直透镜、一个聚焦透镜、光纤支架、准直透镜支架、聚焦透镜支架以及管状壳体。所述多个光纤输出激光模块的输出光纤的输出端固定在光纤支架上；所述多个准直透镜固定在所述准直透镜支架上；所述聚焦透镜固定在所述聚焦透镜支架上；所述光纤支架固定在所述管状壳体内部靠近一端，并使光纤输出端面面向所述管状壳体的另一端；所述准直透镜支架设置在所述管状壳体的内部并邻接光纤支架；所述聚焦透镜支架固定在所述管状壳体的内部并邻接准直透镜组支架；固定在所述光纤支架上的诸光纤输出激光模块的输出光纤端面发出的光通过所述固定在准直透镜组支架上的与之对应的准直透镜后，经固定在所述聚焦透镜支架上的聚焦透镜后，产生所需的复合激光光斑。
所述聚焦透镜中诸片透镜中至少一片透镜的至少一个面与所述聚焦透镜支架上的相应的一片由良导热材料加工的面型相同的透镜框贴合在一起，透镜框上与准直光对应的区域镂空， 让相应光束透过；这种透镜安装结构可大幅增加透镜的散热能力。
与现有技术相比，本发明至少具有以下有益效果：1、本发明的技术方案使热问题的处理难度大幅降低：1)、避免了大功率激光合束器的使用，激光输出分散在多个点处，避免了热的集中，避免了由合束器带来的可靠性问题；2)、激光光学系统中的热问题可以采用技术手段大幅消除；通过分散热问题和采取导热措施，可以大幅降低热效应的影响，提高系统可靠性和特性；2、本发明的技术方案提高了光束质量，同样功率和光斑大小条件下，可使透镜数值孔径变小，透镜片数减少，进一步降低系统热效应。
进一步的，本发明避免采用合束器，降低了系统成本；而在激光光学系统中，全部采用常规光学元件实现，可以大幅降低激光光学系统的成本，并提高系统可靠性；并且，本发明可以降低复合光斑激光加工系统的成本。
进一步的，本发明的激光系统产生的激光光斑具有实时调整光斑结构的能力，提供现有技术无法实现的实时改变光斑结构的能力，增加设备的灵活性和适用性，节省用户的设备采购成本。
附图说明
图1-1A为中心功率大边缘功率小的光斑截面能量分布示意图。
图1-1B为一个环状光斑与一个位于环状光斑中心的点光斑组成的复合光斑截面能量分布示意图。
图1-2A和图1-2B分别为用于焊接或切割的多光点光斑结构示意图。
图1-3A、1-3B、1-3C分别为用于熔覆、焊接和激光热处理的条形、矩形和圆环形光斑结构示意图。
图2-1为实现图1-1A所示光斑的光路结构示意图。
图2-2A为实现图1-2所示光斑结构的光路图；图2-2B为位于图2-2A所示光路聚焦镜前 焦面上3个区域上的光路偏转器件分别示意图。
图2-3为产生图1-3所示光斑的光路示意图，在聚焦镜前焦面附近设置有微透镜阵列。
图3为本发明提出的基于多个光纤输出激光模块的复合光斑激光系统的光路结构示意图。
图4A为依据本发明提出的基于多个光纤输出激光模块的复合光斑激光系统技术方案的由7个准直透镜组成的系统沿光轴方向观察时的准直透镜与聚焦透镜的一种排列结构。
图4B为利用图4A技术方案产生的一种条形光斑结构示意图。
图4C为利用图4A技术方案产生的一种3个分离光斑结构示意图。
图5A为依据本发明提出的基于多个光纤输出激光模块的复合光斑激光系统技术方案的由6个准直透镜组成的系统沿光轴方向观察时的准直透镜与聚焦透镜的一种排列结构。
图5B为利用图5A技术方案产生的一种矩形光斑结构示意图。
图6A为依据本发明提出的基于多个光纤输出激光模块的复合光斑激光系统技术方案的由4个准直透镜组成的系统沿光轴方向观察时的准直透镜与聚焦透镜的一种排列结构。
图6B为利用图6A技术方案产生的一种环形光斑结构示意图。
图6C为利用图6A技术方案产生的一种矩形环状光斑结构示意图。
图6D为利用图6A技术方案产生的一种边缘环状光斑中心点光斑的结构示意图。
图7为依据本发明提出的基于多个光纤输出激光模块的复合光斑激光系统技术方案的由6个准直透镜组成的系统沿光轴方向观察时的准直透镜与聚焦透镜的一种排列结构。
图8为本发明提出的利用本发明提出的基于多个光纤输出激光模块的复合光斑激光系统的激光加工头系统的结构示意图。
图9A为一片聚焦透镜示意图；图9B为与图9A所示透镜贴合在一起的由良导热体制作的一片聚焦透镜框架中与透镜贴合部分的结构的侧面示意图；图9C为与图9A所示透镜贴合在一起的由良导热体制作的一片聚焦透镜框架中与透镜贴合部分的结构的正面示意图；
其中：L、L1和L2分别表示激光器；CL、CL-1、CL-2、…、和CL-M分别表示准直透镜；FL表示聚焦透镜，FL-1表示聚焦透镜的某片透镜；BS、BS-1、BS-2分别表示分光器件；WC表示合波器；LA、LA0、LA1、LA2分别表示微透镜阵列；M-1、M-2、…、M-N分别表示光纤输出激光模块。GXJ表示光纤支架；CLZJ表示准直透镜组支架；FLZJ表示聚焦透镜支架，FLJ-1A表示聚焦透镜支架上某片透镜架的某一部分；GZK表示管状壳体。
具体实施方式
下面结合附图和实施例详细说明本发明提出的基于多个光纤输出模块的复合光斑激光系统及利用该系统的激光加工头。
图3为本发明提出的基于多个光纤输出模块的复合光斑激光加工头的光路结构示意图。它由N个光纤输出激光模块、M个准直透镜和一个聚焦透镜组成。其中：M小于等于N，即准直透镜数小于等于光纤输出激光模块数，N个光纤输出模块M-1、M-2、…、M-N分成M组，每组对应M个准直透镜CL-1、CL-2、…、和CL-M中的一个，每组光纤输出激光模块输出光纤的端面位于相对应的准直透镜的前焦面附近；聚焦透镜FL位于M个准直透镜后方；由N个光纤输出激光模块输出的光通过相应的准直透镜后，由聚焦透镜成像到后焦面附近，形成复合光斑。根据该技术方案，通过调整光纤输出激光模块M-1、M-2、…、M-N的输出光纤端面的位置、光纤芯的形状和参数、准直透镜CL-1、CL-2、…、和CL-M的参数及聚焦透镜FL的参数，可以方便设计出各种结构的激光光斑。
在该技术方案中，通常M个准直透镜的光轴平行，且与聚焦透镜FL的光轴平行。光纤输出激光模块M-1、M-2、…、M-N的输出光纤芯的形状可以是圆形的，也可以是矩形的。
在该技术方案中，可以通过调整光纤输出激光模块M-1、M-2、…、M-N的输出光纤端面的位置、光纤芯的形状和参数、准直透镜CL-1、CL-2、…、和CL-M的参数及聚焦透镜FL的参数，可以将所有光纤输出激光模块的输出光纤端面在聚焦透镜FL的后焦面附近成的像重叠 在一起，形成复合光斑。每个准直透镜对应的光纤端面成的像大小可以相同，也可以不同；当像的大小不同时，就可以形成中间区域功率高、边缘区域功率低的光斑结构。
在该技术方案中，可以通过调整光纤输出激光模块M-1、M-2、…、M-N的输出光纤端面的位置、准直透镜CL-1、CL-2、…、和CL-M的参数及聚焦透镜的参数，将所有光纤输出激光模块的输出光纤端面的像在聚焦透镜FL的后焦面上排列成一个条形光斑。
在该技术方案中，可以通过调整光纤输出激光模块M-1、M-2、…、M-N的输出光纤端面的位置、准直透镜CL-1、CL-2、…、和CL-M的参数及聚焦透镜的参数，将所有光纤输出模块的输出光纤端面的像在聚焦透镜FL的后焦面上排列成一个矩形光斑。
在该技术方案中，可以通过调整光纤输出激光模块M-1、M-2、…、M-N的输出光纤端面的位置、准直透镜CL-1、CL-2、…、和CL-M的参数及聚焦透镜的参数，将所有光纤输出激光模块的输出光纤端面的像在聚焦透镜FL的后焦面上排列成一个在多个分离区域上分布的光斑。
在该技术方案中，可以通过调整光纤输出激光模块M-1、M-2、…、M-N的输出光纤端面的位置、准直透镜CL-1、CL-2、…、和CL-M的参数及聚焦透镜FL的参数，使所有光纤输出激光模块的输出光纤端面在聚焦透镜FL的后焦面附近成的像沿光轴方向排列成多个点。
在该技术方案中，可以通过调整光纤输出激光模块M-1、M-2、…、M-N的输出光纤端面的位置、准直透镜CL-1、CL-2、…、和CL-M的参数及聚焦透镜FL的参数，使所有光纤输出激光模块的输出光纤端面在聚焦透镜FL的后焦面附近成的像排列成环状结构，可以是圆环结构，也可以是矩形环等结构。
在该技术方案中，可以通过调整光纤输出激光模块M-1、M-2、…、M-N的输出光纤端面的位置、准直透镜CL-1、CL-2、…、和CL-M的参数及聚焦透镜FL的参数，使所有光纤输出激光模块的输出光纤端面在聚焦透镜FL的后焦面附近成的像排列成边缘环状中心点状的光斑 结构。
在该技术方案中，诸光纤输出激光模块可以是连续光激光模块、准连续光激光模块或脉冲激光模块。也就是，诸光纤输出激光模块发光的相对持续时间可以是相同的，也可以是不同的；各光纤输出激光模块发光的相对持续时间内的功率可以是相同的，也可以是不同的；诸光纤输出激光模块发光的相对持续时间可以是同步的，也可以是不同步的；通过控制诸模块的发光规律，可以形成光斑形状随时间变化的光斑结构，满足不同激光加工对光斑的要求。
图8为本发明提出的利用本发明提出的基于多个光纤输出激光模块的复合光斑激光系统的激光加工头系统的结构示意图。包括多个光纤输出激光模块M-1、M-2、…、M-N、与光纤输出激光模块对应的多个准直透镜CL-1、CL-2、…、和CL-M、一个聚焦透镜FL、光纤支架GXJ、准直透镜支架ZZZJ、聚焦透镜支架FLZJ以及管状壳体GZK。其中：多个光纤输出激光模块M-1、M-2、…、M-N的输出光纤的输出端固定在光纤支架GXJ上；多个准直透镜CL-1、CL-2、…、和CL-M固定在所述准直透镜支架ZZZJ上；聚焦透镜FL固定在聚焦透镜支架FLZJ上；所述光纤支架GXJ固定在管状壳体GZK内部靠近一端，并使光纤输出端面面向管状壳体GZK的另一端；准直透镜支架ZZZJ设置在管状壳体GZK的内部并邻接光纤支架GXJ；聚焦透镜支架FLZJ固定在管状壳体的内部并邻接准直透镜组支架ZZZJ；固定在光纤支架GXJ上的诸光纤输出激光模块的输出光纤端面发出的光通过固定在准直透镜组支架ZZZJ上的与之对应的准直透镜及固定在聚焦透镜支架FLZJ上的聚焦透镜后，产生所需的复合激光光斑。利用该激光加工头可以产生目前所需的各种类型的激光光斑结构，满足各种激光加工要求，如激光切割、激光焊接、激光熔覆、激光热处理及激光3D打印等。
该激光头技术方案，理论上可以形成各种结构的激光加工光斑，并且可以使这些光斑具有实时改变光斑结构的能力。
在该激光加工头技术方案中，聚焦透镜中诸片透镜中至少一片透镜的至少一个面与所述聚 焦透镜支架上的相应的一片由良导热材料加工的面型相同的透镜框贴合在一起，透镜框上与准直光对应的区域镂空，让相应光束透过。在实际系统中，为了满足各种像差要求，聚焦透镜通常由多片组成，为了使每片透镜都能很好的散热，应尽可能使每片透镜的两个面都与留有光通道的导热板贴合，每片透镜间通过设计留有一定的间隙，以增加导热板的散热能力。这种透镜安装结构可大幅增加透镜的散热能力。图9给出了这种透镜安装结构的示意图：图9A是聚集透镜中的某片透镜FL-1的示意图；图9B为与图9A透镜某个面对应的透镜框的部分结构FLJ-1A的侧面结构示意图，图9C为与图9A透镜某个面对应的透镜框FLJ-1A的部分结构正面结构示意图，它的与透镜表面对应的表面的面型与透镜相同，两者贴合在一起，在透镜框上与透镜通光部分对应的区域开有通孔，让光通过。制造透镜框的材料是良导热材料，通常采用铜或铝便于加工。
该激光加工头技术方案在热管理上与现有技术方案比有以下优点：1、避免合束器的采用，从技术上回避了热集中问题，激光模块输出点产生的泄漏光被分散在M个准直透镜前，各点处的热泄漏量大幅降低；2、采用M个准直透镜，透镜的尺寸远小于现有技术采用的透镜，对于玻璃这种不良热导体，透镜直径小，冷却路径短，散热效果好，透镜直径小，透镜薄，热效应小；3、聚焦透镜与传统透镜相似，但由于激光束是空间分离的多个光束，用镂空的由良导热体做成的导热板包覆聚焦透镜中各片透镜的表面，镂空处对应准直透镜来的激光束，由于良导热体的导热系数是玻璃的几十倍到上百倍，这种方案可以大幅提升透镜的冷却效果，使透镜的热效应可以忽略。
实施例1：根据本发明提出的基于多个光纤输出激光模块的激光系统的技术方案，本发明的某一实施例中，需要实现49个光纤输出激光模块的光合成为一个光斑的结构，要求光斑直径1.8毫米。该系统采用图4A所示的7个准直透镜和1个聚焦透镜结构，7个准直透镜的光轴平行,7个准直透镜的焦距相同，且前焦面重合，聚焦透镜FL的光轴与准直透镜的光轴平 行，并且与位于中心的准直透镜的光轴重合；波长为915纳米的光纤输出半导体激光模块输出功率为120瓦，输出光纤芯径105微米，包层直径125微米，数值孔径0.22。49个激光模块分成7组，每组7个，7个输出光纤端面对齐，以6个围绕1个的结构排列在一起，每组光纤的端面位于相对应的准直透镜的焦点处；准直透镜焦距30毫米，聚焦透镜焦距150毫米。各组光纤端面在聚焦透镜后焦点处形成直径为1.8毫米的光斑。该激光系统可用于激光焊接、熔覆和3D打印等领域。
实施例2：根据本发明提出的基于多个光纤输出激光模块的激光系统的技术方案，本发明的某一实施例中，需要一个中心区域高功率、边缘区域低功率的光斑，采用图4A所示的7个准直透镜和1个聚焦透镜结构，7个准直透镜的光轴平行，聚焦透镜FL的光轴与准直透镜的光轴平行，并且与位于中心的准直透镜的光轴重合；在该实施例中，7个光纤输出激光模块为波长1064纳米的光纤激光器，功率500至1000瓦，每个模块输出光纤的芯径为20微米，数值孔径为0.06，光纤包层直径400微米。7个准直透镜中，6个焦距50毫米，1个焦距25毫米，透镜间距8毫米，聚焦透镜焦距500毫米。该系统形成的切割光斑为直径200微米的高功率光斑和一个直径400微米的低功率光斑的叠加，高功率光斑的数值孔径约为0.046。该系统可以用于激光切割，特别适用于高反射率金属的切割。因为根据金属的性质，金属表面反射会随温度的升高大幅降低，这种系统中的低功率光斑可以对高功率切割区域提前预热，极大的抑制金属的反射率，保护激光系统。
在该实施例中，将6个形成200微米光斑的激光模块统一控制，将一个形成400微米光斑的激光模块单独控制，就可以根据实际加工工艺需求，灵活改变光斑的功率分布，满足不同的加工要求。
实施例3：根据本发明提出的基于多个光纤输出激光模块的激光系统的技术方案，本发明的某一实施例中，需要一个片状汇聚结构的光斑，其光路中准直透镜和汇聚透镜采用图7所示 结构，6个透镜在一个面内一维排列，6个透镜的光轴平行，6个透镜的焦距相同，且前焦面重合，聚焦透镜FL的光轴与准直透镜的光轴平行，6个准直透镜的分布中心与聚焦透镜光轴重合。在该实施例中，6个光纤输出激光模块为波长1064纳米的光纤激光器，功率500至1000瓦，每个模块输出光纤的芯径为20微米，数值孔径为0.06，光纤包层直径400微米，准直透镜焦距50毫米，透镜间距8毫米，聚焦透镜焦距500毫米。该系统形成的切割光斑的直径为200微米，在窄方向的汇聚光束数值孔径为0.006，在宽方向的汇聚光斑的数值孔径约为0.046。
这种激光系统具有极好的光束质量，适合用于切割曲率半径较大的厚板，会得到好的切割质量和高的切割效率。
实施例4：根据本发明提出的基于多个光纤输出激光模块的激光系统的技术方案，本发明的某一实施例中，需要在沿轴方向两个点上各形成一个光斑，两个光斑间距10毫米，光斑大小1.8毫米。该实施例利用49个波长为976纳米的光纤输出半导体激光模块，输出功率为120瓦，输出光纤芯径105微米，包层直径125微米，数值孔径0.22。该系统采用图4A所示的7个准直透镜和1个聚焦透镜结构，7个准直透镜的光轴平行,聚焦透镜FL的光轴与准直透镜的光轴平行，并且与位于中心的准直透镜的光轴重合；7个准直透镜焦距相同，为30毫米，聚焦透镜焦距150毫米。49个激光模块分成7组，每组7个，7个输出光纤端面对齐，以6个围绕1个的结构排列在一起。每组光纤的端面位于相对应的准直透镜的焦点附近；将位于边缘的6组端面分成交替设置的两组，通过调整其中一组中的3个与位于中心那组端面在准直透镜前的位置，使其成像在聚焦透镜后焦点前光轴上5毫米处；通过调整另一组3个端面在准直透镜前焦点附近的位置，使其成像在聚焦透镜后焦点后光轴上5毫米处。这种光斑，可以在两个像点附近的位置上，得到中心高功率边缘低功率的光斑结构，功率分布可随位置变化。该激光系统可用于激光焊接、熔覆和3D打印等领域。
在该实施例中，我们将成像在同一点的诸激光模块作为一组统一控制，通过调整两组模块 的相对功率，可以得到中心功率和边缘功率可控的激光光斑，满足不同的激光加工工艺要求。
实施例5：根据本发明提出的基于多个光纤输出激光模块的激光系统的技术方案，本发明的某一实施例中，要求实现图4B所示光斑结构，为比例长宽7:1的条形光斑。在该实施例中，准直透镜采用图4A所示结构，7个透镜的光轴平行,7个透镜的焦距相同，且前焦面重合，聚焦透镜FL的光轴与准直透镜的光轴平行，并且与位于中心的准直透镜的光轴重合。在该实施例中，7个光纤输出模块的输出光纤的纤芯采用方形结构，其光纤端面位于相应准直透镜的前焦面上，各光纤芯的相应边平行设置，若以D表示光纤边的长度，将7根光纤端面在平行于光纤芯某个边的方向上分别离焦点的距离设置为3D、2D、D、0、-D、-2D及-3D，即可在汇聚透镜的后焦面上获得图4B所示光分布。这种光斑广泛用于激光热处理和激光熔覆领域。
实施例6：根据本发明提出的基于多个光纤输出激光模块的激光系统的技术方案，本发明的某一实施例中，要求实现图4C所示光斑结构，为一个方形光斑和两个圆形光斑组成的复合光斑。在该实施例中，准直透镜采用图4A所示结构，7个透镜设置在同一个平面内，它们的光轴平行，聚焦透镜FL的光轴与准直透镜的光轴平行，并且与位于中心的准直透镜的光轴重合。在该实施例中，7个透镜中5个透镜的焦距为f1，2个透镜的焦距为f2，5个焦距为f1的透镜所对应的光纤输出模块的输出光纤的纤芯采用方形结构，其光纤端中心位于相应准直透镜的前焦面上，各光纤芯的相应边平行设置，2个焦距为f2的透镜所对应的光纤输出模块的输出光纤的纤芯采用圆结构，其光纤中心分别在焦面内两个方向上偏离焦点，即可在汇聚透镜的后焦面上获得图4C所示光分布。在该实施例中，光波波长、光纤芯尺寸、透镜焦距等参数可以灵活设置，增加设计灵活性。这种光斑广泛用于激光焊接领域。
在该实施例中，将方形光斑对应的5个激光模块统一控制，将2个圆形光斑对应的模块统一控制，可以对方形光斑和圆形光斑的功率分布控制，以满足不同激光加工工艺的要求。
实施例7：根据本发明提出的基于多个光纤输出激光模块的激光系统的技术方案，本发明 的某一实施例中，要求实现图5B所示光斑结构，为一矩形光斑。在该实施例中，准直透镜采用图5A所示结构，6个透镜位于同一平面，且光轴平行，6个透镜的焦距相同，聚焦透镜FL的光轴与准直透镜的光轴平行，6个透镜的分布中心与聚焦透镜的光轴重合。在该实施例中，6个光纤输出模块的输出光纤的纤芯采用方形结构，其光纤端面位于相应准直透镜的前焦面上，各光纤芯的相应边平行设置，若以D表示光纤边的长度，将4根光纤端面在平行于光纤芯边方向设置的坐标系中设置在(-D,D/2)、(0,D/2)、(D,D/2)、(-D,-D/2)、(0,-D/2)及(D,-D/2)，即可在汇聚透镜的后焦面上获得图5B所示光分布。这种光斑广泛用于激光热处理领域。
实施例8：根据本发明提出的基于多个光纤输出激光模块的激光系统的技术方案，本发明的某一实施例中，要求实现图6B所示的圆环形光斑，环形光斑直径16毫米，环款2.1毫米。在该实施例中，激光系统的准直透镜和聚焦透镜采用图6A所示结构。4个准直透镜光轴平行，聚焦透镜FL的光轴与准直透镜的光轴平行，并位于4个准直透镜光轴的对称中心处。所设计的一组参数设置为：48个波长915的光纤输出半导体激光模块的输出功率为120瓦，输出光纤芯径105微米，包层直径125微米，数值孔径0.22；这48个模块分成12个一组，其输出光纤的端面对齐，光纤轴线等角间距排列在直径为800微米的圆周上；准直透镜焦距20毫米，聚焦透镜焦距400毫米。通过调整每组光纤端面在准直透镜前焦点处的位置，可以在聚焦透镜后焦面上使每两组光纤组成一个直径16毫米的光纤端面连续排列的圆环，将这两个圆环沿圆周方向错二分之一个光纤像距，可以形成一个高均匀度的圆环状激光光斑。该系统可用于环状焊缝的激光焊接。
实施例9：根据本发明提出的基于多个光纤输出激光模块的激光系统的技术方案，本发明的某一实施例中，要求实现图6C所示的矩形环光斑，矩形环状激光光斑尺寸为13.75毫米X11.25，光斑宽度约1毫米。在该实施例中，激光系统的准直透镜和聚焦透镜采用图6A所示结构。4个准直透镜光轴平行，聚焦透镜FL的光轴与准直透镜的光轴平行，并位于4个准直 透镜光轴的对称中心处。所设计的一组参数设置为：40个波长915的光纤输出半导体激光模块的输出功率为120瓦，输出光纤芯径105微米，包层直径125微米，数值孔径0.22；这42个模块分成4组，其中两组各有12个，另两组各有8个；其输出光纤的端面对齐，沿直线以125微米间距排列；准直透镜焦距20毫米，聚焦透镜焦距200毫米。通过调整每组光纤端面在准直透镜前焦点处的位置，可以在聚焦透镜后焦面上使四组光纤组成一个13.75毫米X11.25的矩形环状激光光斑，光斑线宽约1.05毫米。该系统可用于矩形环状焊缝的激光焊接。
实施例10：根据本发明提出的基于多个光纤输出激光模块的激光系统的技术方案，本发明的某一实施例中，要求实现图6D所示光斑，即中心一个点状光斑及围绕该光斑的一个环形光斑，要求中心光斑直径2毫米，环形边缘光斑外径6毫米，环宽度1毫米。在该实施例中，激光系统的准直透镜和聚焦透镜采用图6A所示结构。4个准直透镜光轴平行，聚焦透镜FL的光轴与准直透镜的光轴平行，并位于4个准直透镜光轴的对称中心处。所设计的一组参数设置为：24个波长915的光纤输出半导体激光模块的输出功率为120瓦，输出光纤芯径105微米，包层直径125微米，数值孔径0.22；2个波长1064微米的光纤激光器模块，输出功率1000瓦，输出光纤芯径100微米，数值孔径0.1。其中：24个半导体激光模块分成两组，每组12个，其输出光纤的端面对齐，光纤轴线等角间距排列在直径为500微米的圆周上，与其对应的准直透镜焦距20毫米，聚焦透镜焦距200毫米；通过调整每组光纤端面在准直透镜前焦点处的位置，可以在聚焦透镜后焦面上使每组光纤组成一个直径5毫米的光纤端面连续排列的圆环，将这两个圆环沿圆周方向错二分之一个光纤像距，可以形成一个高均匀度的圆环状激光光斑；2个光纤激光模块对应的准直透镜的焦距为10毫米，通过调整每根光纤端面在准直透镜前焦点处的位置，可以在聚焦透镜后焦面上使两根光纤形成的直径2毫米的光斑叠加在一起；该点光斑与前面的环形光斑一起构成所要求的激光加工光斑。该激光光斑用于焊接，可极大的抑制焊接过程中的金属溅射，避免对激光光学系统的损伤并提高焊缝质量。
在该实施例中，将环形光斑对应的激光模块统一控制，将中心点状光斑对应的模块统一控制，可以对不同区域的功率分布进行控制，以满足不同激光加工工艺的要求。
实施例11：根据本发明提出的利用多个本发明提出的基于多个光纤输出激光模块的激光系统的激光加工头的技术方案，本发明的某一实施例中，需要一个激光加工头，其光斑具有中心功率高边缘区域低的结构。激光系统采用图4A所示的7个准直透镜和1个聚焦透镜结构，激光头采用图8所示结构，即将多个光纤输出激光模块的输出光纤的输出端固定在光纤支架上；多个准直透镜固定在所述准直透镜支架上；聚焦透镜固定在所述聚焦透镜支架上；光纤支架固定在所述管状壳体内部靠近一端，并使光纤输出端面面向所述管状壳体的另一端；准直透镜支架设置在管状壳体的内部并邻接光纤支架；聚焦透镜支架固定在管状壳体的内部并邻接准直透镜组支架；固定在光纤支架上的诸光纤输出激光模块的输出光纤端面发出的光通过固定在准直透镜组支架上的与之对应的准直透镜后，经固定在聚焦透镜支架上的聚焦透镜后，产生所需的复合激光光斑。
在该实施例中，光学部分的相关技术参数为：7个准直透镜的光轴平行,7个准直透镜的焦距相同，且前焦面重合，聚焦透镜FL的光轴与准直透镜的光轴平行，并且与位于中心的准直透镜的光轴重合；在该实施例中，7个光纤输出激光模块为波长1064纳米的光纤激光器，功率500至1000瓦，每个模块输出光纤的芯径为20微米，数值孔径为0.06，光纤包层直径400微米。7个准直透镜中，6个焦距50毫米，1个焦距25毫米，透镜间距8毫米，聚焦透镜焦距500毫米。该系统形成的切割光斑为直径200微米的高功率光斑和一个直径400微米的低功率光斑的叠加，直径200微米光斑由6个激光模块输出光叠加而成，400微米直径光斑由一个模块产生。高功率光斑的数值孔径约为0.046。
在该实施例中，机械部件的相关参数为：光纤支架GXJ为一直径30毫米的圆柱体，在圆柱体中心轴开有一通孔，在以圆柱体中心轴为中心直径16毫米的圆周上均匀开有6个通孔； 准直透镜支架ZZZJ为一直径30毫米的圆盘，在圆盘的中心轴上开有直径7.2毫米的通孔，在以圆盘中心轴为中心直径16毫米的圆周上均匀开有6个直径7.2毫米的通孔；聚焦透镜支架FLZJ为一外径30毫米，内径26毫米的圆环体；管状壳体GZK的内孔为直径30毫米的圆孔。
在该实施例中：7个光纤输出激光模块的输出光纤设置在柱状光纤支架的7个孔中；7个准直透镜设置在盘状准直透镜支架ZZZJ的7个孔中；聚焦透镜设置在环状聚焦透镜支架FLZJ的内孔中；光纤支架GXJ固定管状壳体GZK内孔中靠近一端，准直透镜支架ZZZJ固定在管状壳体GZK内，邻接光纤支架GXJ，光纤支架上的诸激光输出模块的输出光纤端面与准直透镜支架上的准直透镜一一对应，并位于相应的焦点附近；聚焦透镜支架FLZJ固定在管状壳体GZK内，邻接准直透镜支架ZZZJ。
在该实施例中，波长1064的激光模块输出光纤端面发出的光，通过相应的准直透镜及一个共用的聚焦透镜后，在聚焦透镜的后焦面上形成一个中心功率高、边缘功率低的激光光斑，该光斑适合用于激光切割，尤其适用于高反射率金属的切割。因为根据金属的性质，金属表面反射会随温度的升高大幅降低，这种系统中的低功率光斑可以对高功率切割区域提前预热，极大的抑制金属的反射率，保护激光系统。
在该实施例中，焦距500毫米聚焦透镜采用两片分离透镜形成一个消色差和球差的透镜，其中：面向准直光的透镜为一双凸透镜，材料为石英玻璃，面向准直光的面的曲率半径分布为118.06，另一个面的曲率半径为168.98，中心厚度为2毫米；另一片透镜为双凹透镜，材料为F2玻璃，与第一片透镜中心间距为2毫米，面向前一片透镜的面的曲率半径为160.54，另一面的曲率半径为760.12。
根据该透镜特点，两片透镜的外表面采用图9A-图9C所示结构进行冷却。透镜框采用紫铜加工而成。双凸透镜面向准直光面对应的透镜框为凹面，曲率半径118.06，在以顶点为中心直径16.02的圆周上，均匀开6个直径6.5的孔，在顶点处开一直径6.5的孔，顶点处框架厚 度8毫米。双凹透镜面向工作面对应的透镜框为凸面，曲率半径760.12，在以顶点为中心直径15.79的圆周上，均匀开6个直径6.3的孔，在顶点处开一直径6.3的孔，顶点处框架厚度8毫米。采用这种结构可以极大提高聚焦透镜的散热能力。
本发明提出的基于多个光纤输出激光模块的复合光斑激光系统及利用该系统的加工头，可以提供激光加工所需的各种光斑，并且具有实时改变光斑结构的能力，能满足各种激光加工的要求。在技术上，较好的解决了系统中的热问题，使系统可靠、特性稳定。由于直接采用小功率的激光模块，避免大功率激光器的使用，同时使用常规光学元件，降低了激光加工系统的成本。

Claims (10)

  1. 基于多个光纤输出激光模块的复合光斑激光系统，其特征在于，包括多个光纤输出激光模块、与光纤输出激光模块对应的多个准直透镜以及一个聚焦透镜；所述光纤输出激光模块的输出光纤端面位于与之对应的准直透镜的前方焦点附近，所述准直透镜至少包括一片透镜；所述聚焦透镜至少包括一片透镜，位于诸准直透镜的后方；每一个光纤输出激光模块的输出光纤端面经与之相对应的准直透镜后，由聚焦透镜聚成像到后焦点附近，这些像点组合起来形成复合光斑。
  2. 根据权利要求1所述的基于多个光纤输出激光模块的复合光斑激光系统，其特征是：所述诸准直透镜的光轴平行，在空间并行设置；聚焦透镜光轴与准直透镜光轴平行；所述光纤输出激光模块输出光纤的芯的横截面的形状是圆形的，或者是矩形的。
  3. 根据权利要求1所述的基于多个光纤输出激光模块的复合光斑激光系统，其特征是：通过调整激光模块光纤输出端面位置、纤芯形状、纤芯尺寸及所对应准直透镜焦距，使诸所述光纤输出激光模块输出光纤端面通过对应的准直透镜及所述聚焦透镜后在焦面附近成的像叠加在一起形成一个单一的光斑，光斑区域的强度相同；或者光斑区域内中间功率高，边缘功率低。
  4. 根据权利要求1所述的基于多个光纤输出激光模块的复合光斑激光系统，其特征是：通过调整激光模块光纤输出端面位置、纤芯形状、纤芯尺寸及所对应准直透镜焦距，使诸所述光纤输出激光模块输出光纤端面通过对应的准直透镜及所述聚焦透镜后在焦面附近成的像排成一条形光斑，或者排列成一个矩形光斑。
  5. 根据权利要求1所述的基于多个光纤输出激光模块的复合光斑激光系统，其特征是：通过调整激光模块光纤输出端面位置、纤芯形状、纤芯尺寸及所对应准直透镜焦距，使诸所述光纤输出激光模块输出光纤端面通过对应的准直透镜及所述聚焦透镜后在焦面附近成的像形成分布在几个分离区域的光斑。
  6. 根据权利要求1所述的基于多个光纤输出激光模块的复合光斑激光系统，其特征是：通过调整激光模块光纤输出端面位置、纤芯形状、纤芯尺寸及所对应准直透镜焦距，使诸所述光纤输出激光模块输出光纤端面通过对应的准直透镜及所述聚焦透镜后在焦面附近成的像形成沿透镜光轴方向排列的光斑。
  7. 根据权利要求1所述的基于多个光纤输出激光模块的复合光斑激光系统，其特征是：通过调整激光模块光纤输出端面位置、纤芯形状、纤芯尺寸及所对应准直透镜焦距，使诸所述光纤输出激光模块输出光纤端面通过对应的准直透镜及所述聚焦透镜后在焦面附近成的像形成环状结构的光斑；或者形成由一个环状结构的光斑及一个位于环状光斑中心的点状光斑组成的光斑。
  8. 根据权利要求1所述的基于多个光纤输出激光模块的复合光斑激光系统，其特征是：所述诸光纤输出激光模块发光的相对持续时间是相同的，或者是不同的；各光纤输出激光模块发光的相对持续时间内的功率是相同的，或者是不同的；诸光纤输出激光模块发光的相对持续时间是同步的，或者是不同步的。
  9. 一种利用权利要求1所述复合光斑激光系统的激光加工头，其特征是：包括多个光纤输出激光模块、与光纤输出激光模块对应的多个准直透镜、一个聚焦透镜、光纤支架、准直透镜支架、聚焦透镜支架以及管状壳体；所述多个光纤输出激光模块的输出光纤的输出端固定在光纤支架上；所述多个准直透镜固定在所述准直透镜支架上；所述聚焦透镜固定在所述聚焦透镜支架上；所述光纤支架固定在所述管状壳体内部靠近一端，并使光纤输出端面面向所述管状壳体的另一端；所述准直透镜支架设置在所述管状壳体的内部并邻接光纤支架；所述聚焦透镜支架固定在所述管状壳体的内部并邻接准直透镜组支架；固定在所述光纤支架上的诸光纤输出激光模块的输出光纤端面发出的光通过所述固定在准直透镜组支架上的与之对应的准直透镜后，经固定在所述聚焦透镜支架上的聚焦透镜后，产生所需的复合激光光斑。
  10. 根据权利要求9所述的基于多个光纤输出激光模块的复合光斑激光系统的激光加工头，其特征是：所述聚焦透镜中诸片透镜中至少一片透镜的至少一个面与所述聚焦透镜支架上的相应的一片由良导热材料加工的面型相同的透镜框贴合在一起，透镜框上与准直光对应的区域镂空，让相应光束透过。
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Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003251480A (ja) * 2002-03-01 2003-09-09 Toyota Motor Corp レーザクラッド装置およびレーザ照射装置
JP2013139039A (ja) * 2011-12-28 2013-07-18 Muratani Kikai Seisakusho:Kk レーザ加工装置及びレーザ加工方法
WO2015169513A1 (de) * 2014-05-06 2015-11-12 Siemens Aktiengesellschaft Anordnung und verfahren zum schichtweisen erstellen einer auftragschicht
CN105312783A (zh) * 2014-07-31 2016-02-10 株式会社其恩斯 激光处理装置
CN107442929A (zh) * 2013-12-13 2017-12-08 应用材料公司 光纤阵列线路发生器
CN108778610A (zh) * 2016-03-31 2018-11-09 株式会社村谷机械制作所 激光加工装置和激光加工方法
CN210587643U (zh) * 2019-08-14 2020-05-22 方强 基于多个光纤输出激光模块的复合光斑激光系统及加工头
CN111375890A (zh) * 2019-08-14 2020-07-07 方强 基于多个光纤输出激光模块的复合光斑激光系统及加工头

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003251480A (ja) * 2002-03-01 2003-09-09 Toyota Motor Corp レーザクラッド装置およびレーザ照射装置
JP2013139039A (ja) * 2011-12-28 2013-07-18 Muratani Kikai Seisakusho:Kk レーザ加工装置及びレーザ加工方法
CN107442929A (zh) * 2013-12-13 2017-12-08 应用材料公司 光纤阵列线路发生器
WO2015169513A1 (de) * 2014-05-06 2015-11-12 Siemens Aktiengesellschaft Anordnung und verfahren zum schichtweisen erstellen einer auftragschicht
CN105312783A (zh) * 2014-07-31 2016-02-10 株式会社其恩斯 激光处理装置
CN108778610A (zh) * 2016-03-31 2018-11-09 株式会社村谷机械制作所 激光加工装置和激光加工方法
CN210587643U (zh) * 2019-08-14 2020-05-22 方强 基于多个光纤输出激光模块的复合光斑激光系统及加工头
CN111375890A (zh) * 2019-08-14 2020-07-07 方强 基于多个光纤输出激光模块的复合光斑激光系统及加工头

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