Multi-wavelength laser for kilowatt-level material processing

Abstract

In some embodiments, an optical system includes a laser engine including a plurality of laser sources configured to generate a plurality of lasers associated with different wavelengths and a signal combiner configured to combine the plurality of lasers associated with different wavelengths into a broadband laser. In some embodiments, the optical system may also include a machining cable configured to transmit the broadband laser light and a machining head configured to receive the broadband laser light via the machining cable, such that the machining head may focus the broadband laser light onto the workpiece.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This patent application claims priority to U.S. Provisional Application No. 63 / 507,912, filed on June 13, 2023, entitled “MULTI-WAVELENGTH LASER FORKILOWATT MATERIAL PROCESSING.” Technical Field

[0003] The present disclosure relates generally to laser material processing and to a signal combiner that can combine laser light associated with different wavelengths in a manner that can maintain brightness and avoid nonlinear effects, such as stimulated Raman scattering. Background Art

[0004] In physics, the term scattering is often used to describe various physical processes in which some form of moving particle or radiation (e.g., light or sound) is forced to deviate from a straight-line trajectory due to local inhomogeneities in the medium through which the particle or radiation is traveling. For example, Raman scattering (or the Raman effect) is the inelastic scattering of photons by matter, meaning that there is an exchange of energy and a change in the direction of travel of the light. Raman scattering typically involves the energy gained by a molecule when an incident photon from a visible laser is shifted to a lower energy. Summary of the invention

[0005] In some embodiments, a laser engine includes: a plurality of laser sources configured to generate a plurality of lasers associated with different wavelengths; and a signal combiner configured to: receive the plurality of lasers associated with different wavelengths; and combine the plurality of lasers associated with different wavelengths.

[0006] In some embodiments, an optical system includes: a plurality of laser sources configured to generate a plurality of lasers associated with different wavelengths; a signal combiner configured to combine the plurality of lasers associated with different wavelengths into a broadband laser; a processing cable configured to transmit the broadband laser; and a processing head configured to receive the broadband laser transmitted by the processing cable and focus the broadband laser onto a workpiece.

[0007] In some embodiments, a method for laser material processing includes: generating, by an optical system, multiple lasers associated with different wavelengths using multiple laser sources; combining, by the optical system, the multiple lasers associated with different wavelengths into a broadband laser using a signal combiner; transmitting, by the optical system, the broadband laser to a processing head through a processing cable; and focusing, by the optical system, the broadband laser onto a workpiece using the processing head. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1is a diagram showing an example of light scattering.

[0009] Figure 2 is a diagram illustrating an example industrial beam delivery system.

[0010] Figure 3 is a diagram showing an example of a single-wavelength fiber laser system.

[0011] FIG. 4A to FIG. 4B is a diagram illustrating an example multi-wavelength fiber laser system.

[0012] Figure 5 is a flow chart of an example process for laser material processing. DETAILED DESCRIPTION

[0013] The following detailed description of example embodiments refers to the accompanying drawings.The same reference numbers in different drawings may identify the same or similar elements.

[0014] Figure 1 1 is a diagram illustrating an example 100 of light scattering. For example, when a light wave propagates in a medium such as an optical fiber, the light wave interacts with the constituent atoms and molecules within the medium and generates an electric field. In the case where the light wave has a wavelength far from the resonance of the medium, the electric field induces the generation of a time-dependent polarization dipole, which generates a secondary electromagnetic wave, which is generally referred to as light scattering. Because the distance between the scattering centers (particles) is less than the wavelength of the light in the optical fiber, the secondary light wave is coherent for Rayleigh scattering. When the medium is completely uniform, the phase relationship of the emitted wave allows only the forward scattered beam to propagate. However, optical fiber is an inhomogeneous medium in which scattering is caused by microscopic or macroscopic variations in the density, composition or structure of the material through which the light passes. The random ordering of molecules and the presence of dopants result in local variations in density (and therefore refractive index), which results in Rayleigh scattering, which attenuates the forward propagating signal and generates a reverse propagating signal.

[0015] For example, in Figure 1 In FIG. 1 , reference numeral 110 depicts a Rayleigh scattering peak, wherein Rayleigh scattering is a linear scattering process because the scattered power is proportional to the incident power. Furthermore, no energy is transferred to the glass in Rayleigh scattering, and Rayleigh scattering is elastic scattering because the scattered light exhibits no frequency change compared to the incident light. Instead, Rayleigh scattering is attributed to non-propagating density fluctuations. Figure 1 As further shown in FIG. 1 , reference numeral 120 depicts Brillouin lines that appear on either side of a Rayleigh peak, where the Brillouin lines are generated by scattering of acoustic waves moving in opposite directions. Figure 1As further shown in FIG. 1 , reference numeral 130 depicts a Stokes line having a down-shifted frequency to the left of the Rayleigh peak, while reference numeral 140 depicts an anti-Stokes line having an up-shifted frequency to the right of the Rayleigh peak. As shown in reference numeral 150, Raman lines are formed by the interaction of light waves with molecular vibrations in the medium. Brillouin and Raman scattering are inelastic scattering because Brillouin and Raman scattering are associated with frequency shifts.

[0016] like Figure 1 As shown, the Raman spectrum usually contains several sharp bands with intervals between the bands. The separation between the bands usually corresponds to electronic vibrations, and each bandwidth is generated by molecular rotation or reorientation excitation. In the case where the input light is scattered without strongly changing the optical properties of the medium, the scattering is spontaneous, which includes Rayleigh scattering, Brillouin scattering and Raman scattering. When the light intensity increases to a level that causes the optical properties of the medium to be changed, and the scattered light is proportional to the power of the input light, the scattering region becomes excited. In other words, the transition from spontaneous scattering to stimulated scattering corresponds to the transition of the medium behavior from a linear state to a nonlinear state.

[0017] Figure 1 are provided as examples. Other examples can be found in the Figure 1 The examples described are different.

[0018] Figure 2 is a diagram showing an example industrial beam delivery system 200 that may be used in applications such as laser material processing. For example, laser material processing has many advantages, including high productivity, the non-contact nature of material processing, improved quality, and high precision and mobility of the laser beam delivery point. Lasers are used in a variety of industrial applications, including cutting, drilling, welding, brazing, surface annealing, alloying, and / or hardening, among others. For example, in industrial laser applications, the beam delivery system typically includes an optical fiber for delivering a high power and / or high intensity laser beam to a target.

[0019] For example, Figure 2As shown, the industrial beam delivery system 200 may include a fiber laser engine 210 (e.g., a multi-kilowatt (kW) fiber laser engine) that may be connected to a process head 220 in an application area 230 (e.g., a cutting and / or welding area) via a process cable 240, the process cable 240 typically having a length in the range of about 5 to 50 meters (m). The process cable 240 may be provided in a reinforced cable with pluggable input and output ends, and the process head 220 is an optical assembly that includes a socket for receiving the input end of the process cable 240, optics for projecting laser power, and any laser-based processing accessories that may be required, such as an auxiliary gas port. The fiber laser engine 210 may transmit laser light into an optical coupler unit through free space or through a separate optical fiber, and the optical coupler unit may emit laser light into the process cable 240. Thus, the processing cable 240 typically transmits the laser light to the processing head 220, which can then project the laser light onto a workpiece 250 disposed in the application area 230 in order to perform a desired laser material processing task (e.g., cutting, drilling, welding, etc.). For example, the processing head 220 can include free-space optics that focus the laser light onto the workpiece 250 for the desired laser material processing task.

[0020] As described herein, the fiber laser engine 210 in an industrial fiber laser system is typically a kW laser source that can provide laser light with a power in the range of about 10 kW to 50 kW. In a typical configuration, the fiber laser engine 210 is associated with a single wavelength in the range of about 1030 to 1090 nanometers (nm). The processing cable 240 is used to transmit the laser light from the laser engine 210 to the processing head 220, and typically has a long length (e.g., at least 5 m) and a diameter that increases with power (e.g., from 50 micrometers (μm) to 500 micrometers (μm) or microns). For example, the processing cable 240 has a long length because the processing head 220 is typically accelerated quickly in a large machine, and the weight of the fiber laser engine 210 cannot burden a gantry that moves the processing head 220 within the application area 230 to direct the laser light to the material to be cut, welded, engraved, and / or otherwise processed (e.g., a movable beam delivery system allows the laser light to be moved within the application area 230 without having to move the fiber laser engine 210, which may be very heavy). Furthermore, the long length of the process cable 240 may be advantageous because the fiber laser engine 210 may be placed in a well-protected area to facilitate service operations, rather than placing the fiber laser engine 210 near the application area 230 .

[0021] However, the long length of the processing cable 240 may cause various challenges, including optical power loss, pulse broadening, and / or nonlinear limitations. For example, higher laser powers generally result in faster material processing, which creates a demand for higher and higher laser powers in industrial applications (e.g., currently between 15-20 kW). However, as laser powers increase, it becomes increasingly challenging to deliver lasers with high brightness and high power through tens of meters of optical fiber due to problematic nonlinear effects such as stimulated Raman scattering (SRS). For example, as laser powers increase, SRS begins to dominate in continuous wave (CW) industrial fiber lasers or quasi-CW kW fiber lasers that are often used in the cutting and welding industries. In particular, SRS is a nonlinear optical effect in which energy from an optical pump beam is converted to longer wavelengths via vibrational and / or rotational modes or phonons excited in molecules of a glass medium. While this may be useful for certain applications (e.g., turning an optical fiber into a Raman amplifier or tunable Raman laser, or for distributed fiber optic sensors), SRS is undesirable for multi-kW CW industrial fiber lasers or quasi-CW kW fiber lasers used in cutting, welding, and / or other industrial applications. For example, in industrial applications, SRS can transfer energy from one channel to an adjacent channel and / or limit the power that can be propagated without undesirable losses and / or heating, which can negatively impact the industrial process and / or cause damage to equipment. Therefore, as the power levels of industrial kW fiber lasers increase, SRS becomes more problematic, and a need for SRS suppression techniques has emerged. However, existing techniques for avoiding SRS and other nonlinear effects are generally limited to increasing the diameter of the processing cable 240, which significantly reduces laser brightness and complicates the optics of the processing head 220. In addition, although spectral beam combining can theoretically achieve high brightness, spectral beam combining needs to be performed in free space, without power scaling, and lacks stability.

[0022] Figure 2 are provided as examples. Other examples can be found in the Figure 2 The examples described are different. Figure 2 The number and arrangement of devices shown in are provided as examples. In practice, there may be Figure 2 , additional devices, fewer devices, different devices, or differently arranged devices than those shown in . Figure 2 Two or more of the devices shown in may be implemented in a single device, or Figure 2 The single device shown in can be implemented as multiple distributed devices. Additionally or alternatively, Figure 2 The set of devices (eg, one or more devices) shown in the embodiment may execute the method described as being Figure 2 One or more functions performed by the collection of another device shown in the figure.

[0023] Figure 3 2 are diagrams showing examples 200-1 and 200-2 of single wavelength fiber laser systems. In general, examples 200-1 and 200-2 illustrate typical or standard industrial fiber laser configurations, where a fiber laser engine 310 is associated with a single wavelength in the range of about 1030 nm to 1090 nm, and a process cable 340 having a long length (e.g., at least 5 m) and a diameter that increases with power (e.g., from 50 μm to 500 μm or microns) is used to transmit laser light from the laser engine 310 to a process head 320. As described herein, examples 300-1 and 300-2 relate to single wavelength fiber laser systems that can be used to transmit laser light associated with kW power levels of an appropriate wavelength (e.g., between 1030 nm and 1090 nm) using a process cable 340 having a diameter between 50 μm and 500 μm and a length of more than 5 m. For example, in one illustrative configuration described herein, examples 300 - 1 and 300 - 2 may be used to transmit 30 kW laser light at a wavelength of 1070 nm using a process cable 340 having a 100 μm diameter and a 20 m length.

[0024] As shown in example 300-1, a single module fiber laser engine 310 (e.g., a single module for generating a 30 kW laser at 1070 nm) may be used to generate the laser. Alternatively, the laser may be generated by combining multiple fiber laser engines. For example, in Figure 3, example 300-2 depicts a configuration in which three fiber laser engines 310-1, 310-2, 310-3 each generate laser light of the same wavelength (e.g., respective 10 kW laser light at 1070 nm), which are then combined using a 3:1 combiner 315. However, because SRS scales as a function of power divided by active area, in examples 300-1 and 300-2, SRS is additive because the laser light(s) transmitted through the process cable 340 are all at a single wavelength. For example, in a configuration transmitting 30 kW laser light at 1070 nm, the SRS gain is approximately 33 decibels (dB) through a process cable 340 having a length of 20 m. For example, reference numeral 350 depicts an example plot of SRS gain as a function of wavelength, where the use of a single laser or incoherently combining multiple single wavelength laser light results in the use of narrowband laser sources with low SRS thresholds. For example, the SRS threshold generally refers to the minimum intensity or power of the incident laser light required to induce significant SRS in the process cable 340. Below the SRS threshold, the nonlinear effects are typically weak and the SRS process is not noticeable. However, above the SRS threshold, as the intensity or power of the incident light increases, the SRS process becomes more efficient and the Raman-shifted photons become more prominent. Therefore, a relatively low SRS threshold may result in detrimental SRS effects at lower power levels. A common solution to this problem is to increase the diameter of the processing cable 340 (e.g., from 100 μm to 200 μm) and transmit the laser at a reduced brightness. Other suboptimal solutions include shortening the processing cable 340 or stripping out the SRS with a filter at the output.

[0025] Thus, some embodiments described herein relate to multi-wavelength lasers for kW material processing. For example, in some embodiments, an all-fiber, high-power broadband laser can incoherently combine a multi-wavelength fiber laser with a fused fiber signal combiner to deliver a broad spectrum, high brightness laser for material processing while avoiding nonlinear effects such as SRS. In this way, power scaling can be achieved by adding multiple wavelength lasers, which allows the processing cable to have a smaller core diameter, thereby maintaining brightness and avoiding nonlinear effects such as SRS.

[0026] Figure 3 are provided as examples. Other examples can be found in the Figure 3 The examples described are different. Figure 3 The number and arrangement of devices shown in are provided as examples. In practice, there may be Figure 3 , additional devices, fewer devices, different devices, or differently arranged devices than those shown in . Figure 3 Two or more of the devices shown in may be implemented in a single device, or Figure 3The single device shown in can be implemented as multiple distributed devices. Additionally or alternatively, Figure 3 The set of devices (eg, one or more devices) shown in the embodiment may execute the method described as being Figure 3 One or more functions performed by the collection of another device shown in the figure.

[0027] FIG. 4A to FIG. 4B is a diagram showing an example multi-wavelength fiber laser system 400 that can be used for kW material processing or other suitable applications. Figure 4A As shown, the multi-wavelength laser includes a plurality of fiber laser sources 410, 412, 414 connected to a processing head 420 via a processing cable 430, wherein each of the plurality of fiber laser sources 410, 412, 414 operates at a different wavelength. For example, in one configuration, a 30kW multi-wavelength solution can be implemented using a first fiber laser source 410 generating a 10kW laser of a first wavelength (e.g., 1080nm), a second fiber laser source 412 generating a 10kW laser of a second wavelength (e.g., 1075nm), and a third fiber laser source 414 generating a 10kW laser of a third wavelength (e.g., 1070nm). However, in general, a laser engine may include two or more laser sources generating respective lasers associated with different wavelengths, wherein the two or more laser sources may operate at the same power level or at different power levels. In addition, in some embodiments, the lasers associated with different wavelengths are incoherently combined with a fused fiber signal combiner 415, which transmits the incoherently combined lasers to the processing cable 430. In a configuration where the process cable 430 has a core diameter of 100 μm and a length of 20 m, the SRS gain is approximately 11 dB for each laser wavelength, which is a net 3-fold reduction in SRS gain relative to a single laser or incoherently combining multiple single wavelength lasers for the same effective diameter and length of the process cable 430.

[0028] Therefore, if Figure 4A As shown, the multi-wavelength fiber laser system 400 includes a laser engine having multiple laser sources (e.g., laser sources 410, 412, 414), wherein the multiple laser sources are configured to generate multiple lasers associated with different wavelengths. In addition, the laser engine includes a signal combiner 415 to receive the multiple lasers associated with different wavelengths and combine the multiple lasers into a broadband laser, which is transmitted to the processing head 420 through the processing cable 430, and the processing head 420 receives the broadband laser and focuses the broadband laser onto the workpiece ( Figure 4A410). In addition, as described herein, the signal combiner 415 is configured to incoherently combine multiple lasers associated with different wavelengths, whereby the multiple laser sources and the signal combiner 415 are equivalent to a broadband signal source that increases the SRS threshold (e.g., increases the minimum intensity or power of the incident laser, which results in significant SRS in the process cable 430). In addition, in some cases, the multiple lasers generated by the multiple laser sources can be provided at equal power levels (e.g., 10 kW for the multiple fiber laser sources 410, 412, 414 in the example described herein). Additionally or alternatively, in some cases, the multiple lasers generated by the multiple laser sources can be associated with at least two different power levels. For example, different power levels can be used for different lasers, which allows lower power to be used for lower wavelengths, and higher power to be used for lower wavelengths to further reduce SRS. In addition, the multiple lasers can be associated with uniform intervals between different wavelengths (e.g., the laser sources 410, 412, 414 can generate respective lasers of 1080 nm, 1075 nm, and 1070 nm, thereby providing a 5 nm interval between the lasers). In some implementations, the precise spacing between the wavelengths of the multiple laser sources may vary depending on various factors, such as the number of lasers combined by combiner 415 .

[0029] Thus, because SRS is generally scaled as a function of power over the active area, individual signal wavelengths with little overlap relative to SRS gain can be processed individually, allowing laser light to be delivered to the processing head 420 at high power and brightness. Figure 4A , reference numeral 440 depicts a plot of SRS gain as a function of wavelength, wherein the individual signal wavelengths generated by the different fiber laser sources 410, 412, 414 have minimal overlap, which results in different SRS gains for each signal wavelength. Figure 4A , reference numeral 450 depicts a plot equivalent to the plot depicted by reference numeral 440, wherein multiple incoherently combined lasers associated with different wavelengths are equivalent to a broadband signal source, which increases the SRS threshold. In this manner, because the multiple lasers are associated with different wavelengths, the multiple lasers are associated with corresponding SRS gains distributed over different wavelengths. In other words, the SRS gains can be processed separately at different wavelengths relative to a single laser or multiple laser sources operating at the same wavelength, where the SRS gains are additive.

[0030] For example, refer to Figure 4B , reference numeral 460 depicts a comparison between the SRS gain experienced in a single wavelength fiber laser engine and a multi-wavelength fiber laser engine. For example, curve 462 depicts the SRS gain experienced in a single wavelength fiber laser engine (e.g., Figure 3), and curve 464 depicts the SRS gain experienced in a multi-wavelength fiber laser engine (e.g., Figure 4A As shown, the multi-wavelength fiber laser engine exhibits lower SRS gain than the single-wavelength fiber laser engine. In particular, the signal combiner 415 in the multi-wavelength fiber laser system 400 is configured to combine multiple lasers associated with different wavelengths to generate a broadband signal distributed over a range associated with the different wavelengths, which results in an SRS gain that is less than the individual SRS gains associated with the multiple lasers. In this way, the multi-wavelength fiber laser system 400 provides various advantages, such as allowing the processing cable 430 to have a smaller core diameter at kW power levels, which helps maintain brightness and avoid nonlinear effects, such as SRS. For example, in some embodiments, the multi-wavelength fiber laser system 400 can be used to effectively scale power when the processing cable 430 has a core diameter of 100 μm or less and / or when the broadband laser transmitted through the processing cable 430 has a power of at least 10 kW. However, it should be understood that using multiple laser sources that generate corresponding laser light at different wavelengths and incoherently combining the corresponding laser light can be applicable to any laser application that requires suppression of SRS or other nonlinear effects without having to compromise brightness (e.g., by increasing the core diameter of the process cable 430), shorten the process cable 430 (e.g., creating challenges in applications where the process cable 430 requires a long length), and / or increase cost or complexity by deploying filters to strip off SRS at the output end from the process cable 430.

[0031] FIG. 4A to FIG. 4B are provided as examples. Other examples can be found in the FIG. 4A to FIG. 4B The examples described are different. FIG. 4A to FIG. 4B The number and arrangement of devices shown in are provided as examples. In practice, there may be FIG. 4A to FIG. 4B , additional devices, fewer devices, different devices, or differently arranged devices than those shown in . FIG. 4A to FIG. 4B Two or more of the devices shown in may be implemented in a single device, or FIG. 4A to FIG. 4B The single device shown in can be implemented as multiple distributed devices. Additionally or alternatively, FIG. 4A to FIG. 4B A set of devices (eg, one or more devices) shown in FIG. 1 may perform the operations described as being performed by FIG. 4A to FIG. 4B One or more functions performed by another set of devices shown in .

[0032] Figure 5 is a flow chart of an example process 500 associated with kW laser material processing using a multi-wavelength laser. In some embodiments, Figure 5 One or more process blocks of are performed by an optical system (eg, multi-wavelength fiber laser system 400).

[0033] like Figure 5 As shown, process 500 may include generating multiple lasers associated with different wavelengths using multiple laser sources (block 510). For example, as described above, multi-wavelength fiber laser system 400 may generate multiple lasers associated with different wavelengths using multiple laser sources 410, 412, 414.

[0034] like Figure 5 As further shown in FIG. 5 , process 500 may include combining multiple lasers associated with different wavelengths into a broadband laser using a signal combiner (block 520). For example, as described above, multi-wavelength fiber laser system 400 may combine multiple lasers associated with different wavelengths into a broadband laser using signal combiner 415.

[0035] like Figure 5 As further shown in FIG. 5 , process 500 may include transmitting broadband laser light to a process head via a process cable (block 530 ). For example, as described above, multi-wavelength fiber laser system 400 may transmit broadband laser light to process head 420 via process cable 430 .

[0036] like Figure 5 As further shown in FIG. 5 , process 500 may include focusing the broadband laser onto the workpiece using a processing head (block 540 ). For example, as described above, multi-wavelength fiber laser system 400 may use processing head 420 to focus the broadband laser onto the workpiece.

[0037] Process 500 may include additional implementations, such as any single embodiment or any combination of implementations described below and / or any combination of implementations described in conjunction with one or more other processes described elsewhere herein.

[0038] In a first embodiment, the process cable 430 has a core diameter of 100 microns or less and the broadband laser has a power of at least 10 kW.

[0039] In a second embodiment, either alone or in combination with the first embodiment, the signal combiner 415 is configured to incoherently combine multiple lasers associated with different wavelengths.

[0040] In a third embodiment, alone or in combination with one or more of the first and second embodiments, a plurality of lasers are associated with respective SRS gains distributed over different wavelengths.

[0041] In a fourth embodiment, alone or in combination with one or more of the first to third embodiments, broadband lasers are distributed over a range associated with different wavelengths and have gains that are less than individual gains associated with the plurality of lasers.

[0042] although Figure 5 An example block diagram of process 500 is shown, but in some implementations, process 500 includes Figure 5 Additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in process 500. Additionally or alternatively, two or more of the blocks in process 500 may be executed in parallel.

[0043] The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit the embodiments to the precise forms disclosed. Modifications and variations may be made based on the foregoing disclosure, or may be obtained from the practice of the embodiments. In addition, any embodiment described herein may be combined unless the foregoing disclosure explicitly provides a reason why one or more embodiments may not be combined.

[0044] As used herein, satisfying a threshold may refer to a value greater than a threshold, greater than or equal to a threshold, less than a threshold, less than or equal to a threshold, equal to a threshold, not equal to a threshold, etc., depending on the context.

[0045] Even though specific combinations of features are described in the claims and / or disclosed in the specification, these combinations are not intended to limit the disclosure of the various embodiments. In fact, many of these features can be combined in ways that are not specifically described in the claims and / or disclosed in the specification. Although each dependent claim listed below may be directly subordinate to only one claim, the disclosure of the various embodiments includes the combination of each dependent claim with each other claim in the claim set. As used herein, a phrase referring to "at least one" in a list of items refers to any combination of these items, including single members. As an example, "at least one of a, b, or c" is intended to cover a, b, c, ab, ac, bc, and abc, as well as any combination with multiple identical items.

[0046] When a component or one or more components (e.g., a laser emitter or one or more laser emitters) is described or claimed (within a single claim or across multiple claims) as performing multiple operations or being configured to perform multiple operations, the language is intended to broadly cover a variety of architectures and environments. For example, unless otherwise expressly stated (e.g., by using "first component" and "second component" or other language that distinguishes components in the claims), the language is intended to cover a single component that performs or is configured to perform all operations, a group of components that collectively perform or are configured to perform all operations, a first component that performs or is configured to perform a first operation and a second component that performs or is configured to perform a second operation, or any combination of components that perform or are configured to perform operations. For example, when a claim has the form "one or more components are configured to: perform X; perform Y; the claim should be interpreted to mean "one or more components configured to perform X; one or more (possibly different) components configured to perform Y; and one or more (possibly different) components configured to perform Z".

[0047] Unless explicitly described as such, the elements, actions, or instructions used herein should not be interpreted as critical or essential. Furthermore, as used herein, the articles "a" and "an" are intended to include one or more items and can be used interchangeably with "one or more." Furthermore, as used herein, the article "the" is intended to include one or more items referenced in conjunction with the article "the" and can be used interchangeably with "one or more." Furthermore, as used herein, the term "set" is intended to include one or more items (e.g., related items, unrelated items, or a combination of related and unrelated items). In the context of only referring to a set, the term "set" is intended to include one or more items (e.g., related items, unrelated items, or a combination of related and unrelated items). Figure 1 In the case of two or more items, the phrase "only one" or similar language is used. In addition, as used herein, the terms "has," "have," "having," and the like are intended to be open-ended terms. In addition, unless expressly stated otherwise, the phrase "based on" is intended to mean "based at least in part on." In addition, as used herein, the term "or" when used in tandem is intended to be inclusive and can be used interchangeably with "and / or" unless expressly stated otherwise (e.g., if used in combination with "either" or "only one of").

Claims

1. A laser engine, comprising: a plurality of laser sources configured to generate a plurality of lasers associated with different wavelengths; as well as The signal combiner is configured as: receiving the plurality of lasers associated with the different wavelengths; and The plurality of lasers associated with the different wavelengths are combined.

2. The laser engine according to claim 1, wherein: The signal combiner is configured to incoherently combine the plurality of lasers associated with the different wavelengths.

3. The laser engine according to claim 1, wherein: The plurality of lasers generated by the plurality of laser sources are associated with equal power levels.

4. The laser engine according to claim 1, wherein: The plurality of lasers generated by the plurality of laser sources are associated with at least two different power levels.

5. The laser engine according to claim 1, wherein: The plurality of lasers are associated with uniform spacing between the different wavelengths.

6. The laser engine according to claim 1, wherein: The plurality of lasers are associated with respective stimulated Raman scattering (SRS) gains distributed over the different wavelengths.

7. The laser engine according to claim 1, wherein: The signal combiner is configured to combine the plurality of lasers associated with the different wavelengths to generate a broadband signal distributed over a range associated with the different wavelengths and having a gain that is less than individual gains associated with the plurality of lasers.

8. An optical system comprising: a plurality of laser sources configured to generate a plurality of lasers associated with different wavelengths; a signal combiner configured to combine the plurality of lasers associated with the different wavelengths into a broadband laser; a processing cable configured to transmit the broadband laser; as well as The processing head is configured to receive the broadband laser transmitted by the processing cable and is configured to focus the broadband laser onto a workpiece.

9. The optical system according to claim 8, wherein: The processing cable has a core diameter of 100 microns or less, and the broadband laser has a power of at least 10 kilowatts.

10. The optical system according to claim 8, wherein: The signal combiner is configured to incoherently combine the plurality of lasers associated with the different wavelengths.

11. The optical system according to claim 8, wherein: The plurality of lasers generated by the plurality of laser sources are associated with equal power levels.

12. The optical system according to claim 8, wherein: The plurality of lasers generated by the plurality of laser sources are associated with at least two different power levels.

13. The optical system according to claim 8, wherein: The plurality of lasers are associated with uniform spacing between the different wavelengths.

14. The optical system according to claim 8, wherein: The plurality of lasers are associated with respective stimulated Raman scattering (SRS) gains distributed over the different wavelengths.

15. The optical system according to claim 8, wherein: The broadband lasers are distributed over a range associated with the different wavelengths and have gains that are less than individual gains associated with the plurality of lasers.

16. A method for laser material processing, comprising: generating, by an optical system, a plurality of lasers associated with different wavelengths using a plurality of laser sources; combining, by the optical system, the plurality of lasers associated with the different wavelengths into a broadband laser using a signal combiner; The optical system transmits the broadband laser to a processing head via a processing cable; and The broadband laser is focused onto a workpiece by the optical system using the processing head.

17. The method according to claim 16, wherein: The processing cable has a core diameter of 100 microns or less, and the broadband laser has a power of at least 10 kilowatts.

18. The method according to claim 16, wherein: The signal combiner is configured to incoherently combine the plurality of lasers associated with the different wavelengths.

19. The method according to claim 16, wherein: The plurality of lasers are associated with respective stimulated Raman scattering (SRS) gains distributed over the different wavelengths.

20. The method according to claim 16, wherein: The broadband lasers are distributed over a range associated with the different wavelengths and have gains that are less than individual gains associated with the plurality of lasers.

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