KR20230042412A - Application, method and systems for a laser deliver addressable array - Google Patents

Abstract

An assembly is provided for combining a group of laser sources into a combined laser beam. A blue diode laser array combining laser beams from an assembly of blue laser diodes is also provided. Laser processing operations and applications using combined blue laser beams from laser diode arrays and modules are provided.

Description

APPLICATION, METHOD AND SYSTEMS FOR A LASER DELIVER ADDRESSABLE ARRAY

This application has the benefit of 35 U.S.C. §119(e)(1), the entire disclosure of which is hereby incorporated by reference into this application.

The present invention relates to array assemblies for combining laser beams, particularly arrays capable of providing high brightness laser beams for use in systems and applications in fabrication, manufacturing, entertainment, graphics, imaging, analysis, monitoring, assembly, dentistry and medical applications. It's about assembly.

Many lasers, particularly semiconductor lasers such as laser diodes, provide laser beams with highly desirable wavelengths and beam qualities, including luminance. These lasers can have wavelengths in the visible range, UV range, IR range and combinations thereof, as well as higher and lower wavelengths. The technology of semiconductor lasers as well as other laser sources, such as fiber lasers, is evolving rapidly as new laser sources are continuously developed and offer both old and new laser wavelengths. Although having desirable beam quality, many of these lasers have lower laser power than is desirable or required for certain applications. Therefore, their low power has prevented these laser sources from finding greater usefulness and commercial application.

In addition, conventional efforts to combine these types of lasers have resulted in difficulties in beam alignment, difficulty in maintaining beam alignment during application, loss of beam quality, special placement of the laser source, to name but a few among other reasons. It was generally insufficient for reasons of difficulty, size considerations, and output management.

As used herein, unless otherwise specified, the terms "blue laser beam", "blue laser" and "blue" provide a laser beam or light having a wavelength of about 400 nm to about 500 nm, Their broad meaning should be given and generally refers to systems providing such, for example propagating laser beams, laser sources, eg lasers and diode lasers.

In general, the term "about" as used herein, unless otherwise specified, includes a deviation or range of ±10%, which is the experimental or instrumental error associated with obtaining the stated value, preferably whichever is greater. it means to

This Background section of the present invention is intended to introduce various aspects of the art that may be related to embodiments of the present invention. Accordingly, the foregoing discussion in this section provides a basis for a better understanding of the present invention and is not to be regarded as an admission of prior art.

Among other things, there has been a long unmet need for assemblies and systems that combine multiple laser beam sources into a single or multiple laser beams while maintaining and enhancing desired beam qualities such as brightness and power. The present inventors address these needs by providing, among other things, the articles of manufacture, apparatus and processes taught and disclosed herein.

Accordingly, a laser system for performing laser operation is provided, the system including a plurality of laser diode assemblies; each laser diode assembly having a plurality of laser diodes capable of producing individual blue laser beams along a laser beam path; means for spatially combining the individual blue laser beams to create a combined laser beam having a single spot in the far field that can be coupled to an optical fiber for delivery to a target material; and means for spatially combining the individual blue laser beams onto the laser beam path and in optical relationship with each laser diode.

Also provided are methods and systems having one or more of the following features, the features having at least three laser diode assemblies; Each laser diode assembly includes at least 30 laser diodes; The laser diode assembly is capable of propagating a laser beam having a total power of at least about 30 Watts and beam parameter characteristics of less than 20 mm mrad; Beam parameter characteristics are less than 15 mm mrad; Beam parameter characteristics are less than 10 mm mrad; the means for spatially combining produces a combined laser beam of N times the luminance of the individual laser beams, where N is the number of laser diodes in the laser diode assembly; The means for spatially combining increases the power of the laser beam while preserving the luminance of the combined laser beam; the combined laser beam has a power that is at least 50 times the power of the individual laser beams, and the beam parameter product of the combined laser beams is less than twice the beam parameter product of the individual laser beams; the beam parameter product of the combined laser beams is less than or equal to 1.5 times the beam parameter product of the individual laser beams; the beam parameter product of the combined laser beams is less than or equal to 1 times the beam parameter product of the individual laser beams; The means for spatially combining increases the power of the laser beams while preserving the brightness of the individual laser beams; the combined laser beam has a power that is at least 100 times the power of the individual laser beams, and the beam parameter product of the combined laser beams is less than twice the beam parameter product of the individual laser beams; the beam parameter product of the combined laser beams is less than or equal to 1.5 times the beam parameter product of the individual laser beams; the beam parameter product of the combined laser beams is less than or equal to 1 times the beam parameter product of the individual laser beams; The optical fiber is solarization resistant; the spatially combining means having an assembly selected from the group consisting of parallel alignment plates and wedges for correcting at least one of a positional error or orientation error of the laser diode; the means for spatially combining has a deflecting beam combiner capable of increasing the effective luminance of the combined laser beams over individual laser beams; The laser beam assembly defines the individual laser beam paths with respect to the space between the respective paths, so that the individual laser beams have a space between each beam, and the spatial combining means directs the individual laser beams to the fast axis of the laser diode. A collimator for collimating and a periodic mirror for combining the collimated laser beams, the periodic mirror reflecting a first laser beam from a first diode in the laser diode assembly and generating a second laser beam from a second diode in the laser diode assembly. configured to deliver beams, so that spaces between the individual laser beams are filled in the high-velocity direction; The spatially combining means has a patterned mirror on a glass substrate; the glass substrate is of sufficient thickness to divert the vertical position of the laser beam from the laser diodes to fill the empty space between the laser diodes; It has a stepped heat sink.

In addition, a laser system for providing a high-brightness, high-power laser beam is further provided, the system comprising a plurality of laser diode assemblies, each laser diode having a plurality of laser diodes capable of generating a blue laser beam having an initial luminance. assembly, and means for spatially combining the blue laser beams to produce a combined laser beam having a final luminance and forming a single spot in the far field that can be coupled to an optical fiber, each laser diode having a combined laser beam fixed by the external cavity at different wavelengths to substantially increase the luminance of the laser beam so that the final luminance of the combined laser beam is approximately equal to the initial luminance of the laser beam from the laser diode.

Also provided is a method and system having one or more of the following features, wherein each laser diode is fixed to a single wavelength using an external cavity based grating and each laser diode assembly comprises a narrowly spaced optical filter and combined into a combined beam using combining means selected from the group consisting of gratings; A Raman converter is an optical fiber with a pure fused silica core to create a high brightness source and a fluorinated outer core containing blue pump light; The Raman converter is used to pump a Raman converter such as an optical fiber having a GeO ₂ doped central core with an outer core and an outer core larger than the central core containing blue pump light to create a high brightness source; A Raman converter is an optical fiber having a P ₂ O ₂ doped core to create a high brightness source and an outer core larger than the central core to contain blue pump light; A Raman converter is an optical fiber having a graded index core to create a high brightness source and an outer core larger than the central core to contain blue pump light; The Raman converter is a graded GeO ₂ doped core and an external stepped index core; The Raman converter is used to pump a Raman converter fiber, which is a graded P ₂ O ₂ doped core and an outer stepped index core; Raman converters are used to pump Raman converter fibers, which are graded GeO ₂ doped cores; The Raman converter is a graded index P ₂ O ₂ doped core and an external stepped index core; The Raman converter is a diamond generating high-brightness laser source; The Raman converter is a KGW to generate a high-brightness laser source; The Raman converter is YVO ₄ to generate a high-brightness laser source; the Raman converter is Ba(NO ₃ ) ₂ to produce a high-brightness laser source; A Raman transducer is a high-pressure gas that creates a high-brightness laser source.

In addition, a laser system for performing the laser operation is further provided, the system including a plurality of laser diode assemblies, each laser diode assembly having a plurality of laser diodes capable of generating a blue laser beam along a laser beam path; and means for spatially combining the blue laser beams to create a combined laser beam having a single spot in the far field that can be optically coupled to the Raman converter, pumped into the Raman converter, and increasing the brightness of the combined laser beam. includes

Also provided is a method of manufacturing a combined laser beam, the method comprising an array of Raman converted lasers to generate a blue laser beam and a combined laser beam at individual different wavelengths to create a high power source while preserving the spatial luminance of the original source. has steps to make it work.

Still further, a laser system for performing the laser operation is provided, the system including a plurality of laser diode assemblies, each laser diode assembly having a plurality of laser diodes capable of producing a blue laser beam along a laser beam path, aiming and beam collimation and combining optics along the laser beam path, to which the combined laser beam can be provided, and an optical fiber to receive the combined laser beam.

Also provided are methods and systems having one or more of the following features, wherein the optical filter is in optical communication with the rare earth doped fiber so that the combined laser beam traverses the rare earth doped fiber to create a high brightness laser source. pumpable; An optical fiber is in optical communication with the outer core of the high brightness converter so that the combined laser beam can pump the outer core of the brightness converter to produce a higher percentage brightness enhancement.

Still further, a double core, one of which is a high-brightness central core; and means for suppressing secondary Raman signals in the high brightness central core selected from the group consisting of filters, fiber Bragg gratings, first and second order Raman signals of order V, and micron bend loss differences.

Also provided is a second harmonic generation system, comprising a Raman converter of a first wavelength for generating light at a half wavelength of the first wavelength, and an external resonance configured to prevent the half wavelength light from propagating through the optical fiber. have double crystals.

Also provided are methods and systems having one or more of the following features, wherein the first wavelength is about 460 nm, the external resonant double crystal is a KTP, and the Raman converter is structured to improve Raman conversion efficiency. It has a circular outer core.

Also provided is a third harmonic generation system comprising a Raman converter of a first wavelength to generate light at a second wavelength lower than the first wavelength, and to prevent the lower wavelength light from propagating through the optical fiber. It has an external resonant double crystal composed of

Also provided is a fourth harmonic generation system, which system has a Raman converter that generates light at 57.5 nm using an external resonant double crystal configured to prevent 57.5 nm wavelength light from propagating through an optical fiber.

In addition, a second harmonic generation system is provided, which system does not allow short-wavelength light to propagate through an optical fiber, but uses an external resonant double crystal at 450 nm to generate light at half the wavelength of the source laser or 236.5 nm. It has a rare earth doped luminance converter containing thulium that fires a laser at 473 nm when pumped by an array of blue laser diodes.

Also provided is a third harmonic generation system, which does not allow short wavelength light to propagate through an optical fiber but uses an externally resonant double crystal to an array of blue laser diodes at 450 nm to generate light at 118.25 nm. It has a rare-earth doped luminance converter containing thulium that fires a laser at 473 nm when pumped by

Also provided is a fourth harmonic generation system, which does not allow short wavelength light to propagate through an optical fiber but uses an externally resonant double crystal to an array of blue laser diodes at 450 nm to generate light at 59.1 nm. It has a rare-earth doped luminance converter with thulium that fires a laser at 473 nm when pumped by .

Still further, a laser system for performing laser operation is provided, the system including at least three laser diode assemblies; At least a laser diode assembly, each having at least 10 laser diodes, each of the at least 10 laser diodes producing a blue laser beam along a laser beam path with a power of at least about 2 Watts and a beam parameter product of less than 8 mm-mrad. which may include at least a laser diode assembly; and means for spatially combining and preserving the luminance of the blue laser beam, all located in at least 30 laser beam paths, comprising: collimating optics for a first axis of the laser beam, a vertical prism array for a second axis of the laser beam, and The telescope has means for providing a combined laser beam with a power of at least about 600 Watts and a beam parameter product of less than 40 mm-mrad by filling a space between the laser beams with laser energy.

Still furthermore, an addressable array laser processing system is provided, the addressable array laser processing system having at least three laser systems of the type described herein and a control system, each of the at least three laser systems having their combination in a single optical fiber. Configured to couple each of the laser beams so that each of the at least three combined laser beams can be directed along its coupled optical fiber, the at least three optical fibers being optically associated with the laser head, and the control system providing a control system on the target material. It has a program with a predetermined sequence for delivering each of the combined laser beams to a predetermined location.

Also provided is a method and system for an addressable array having one or more of the following features, wherein a predetermined sequence for delivery has individually turned on and off the laser beams from the laser head, thereby forming a target with powder. imaging onto the powder bed to melt and fuse the material into a part; The fibers in the laser head are configured in an arrangement selected from the group consisting of linear, non-linear, circular, rhomboidal, square, triangular, and hexagonal; the fibers in the laser head are configured in an arrangement selected from the group consisting of 2 x 5, 5 x 2, 4 x 5, at least 5 x at least 5, 10 x 5, 5 x 10 and 3 x 4; The target material has a powder bed, an x-y motion system capable of transporting a laser head across the powder bed to melt and fuse the powder bed, and a powder delivery system positioned behind the laser source to provide a new powder layer behind the fused layer. has; having a z-motion system that can move the laser head to increase and decrease the height of the laser head above the surface of the powder bed; having a bi-directional powder placement device capable of placing the powder directly behind the delivered laser beam as it moves in the positive x direction or the negative x direction; having a powder supply system coaxial with the plurality of laser beam paths; has a gravity fed powder system; having a powder supply system in which the powder is entrained in an inert gas flow; having a powder supply system transverse to the N(N≧1) laser beam, in which the powder is placed by gravity in front of the laser beam; It has a powder supply system transverse to the N(N≧1) laser beam, where the powder is entrained in an inert gas flow intersecting the laser beam.

Still also, a method is provided for providing a combined blue laser beam with high brightness, comprising operating a plurality of Raman converted lasers to provide a plurality of individual blue laser beams, and preserving the spatial luminance of the original source. and combining the individual blue laser beams to create a high power source while the plurality of individual laser beams have different wavelengths.

Also provided is a method of laser processing a target material, the method comprising an addressable array laser processing system having at least three laser systems of the type described herein to generate individual laser beams combined into three individual optical fibers. operating each combined laser beam along its optical fiber to the laser head, and directing the combined three individual laser beams from the laser head in a predetermined order to predetermined locations on the target material. have steps

An array assembly according to the present invention provides an array assembly for combining laser beams, particularly high brightness laser beams for use in systems and applications in fabrication, manufacturing, entertainment, graphics, imaging, analysis, monitoring, assembly, dental and medical applications. can do.

1 is a graph showing the laser performance of an embodiment according to the present invention.
2a is a schematic diagram of a laser diode and an axial focus lens according to the present invention.
2B is a schematic diagram of an embodiment of a laser diode spot after fast and slow axis focusing according to the present invention.
2C is a perspective view of an embodiment of a laser diode assembly according to the present invention.
2d is a perspective view of an embodiment of a laser diode module according to the present invention.
Figure 2E is a partial view of the embodiment of Figure 2C showing a laser beam, laser beam path and spacing between laser beams in accordance with the present invention.
FIG. 2F is a cross-sectional view of a laser beam, laser beam path and space between the laser beams of FIG. 2E.
2g is a perspective view of an embodiment of a laser beam, laser beam path and optical system according to the present invention.
2H is a diagram of a combined laser diode beam after a patterned mirror in accordance with the present invention.
Figure 2i is a diagram of a laser diode beam after a beam folder with equal splitting of the beam according to the present invention.
2j is a diagram of a laser diode beam after a beam folder with a 3-2 column split according to the present invention.
Figure 3 is a schematic diagram illustrating a scanning embodiment of an embodiment of a laser diode array on a starting material or target material according to the present invention.
4 is a table providing processing parameters according to the present invention.
5 is a schematic diagram of an embodiment of a laser array system and process according to the present invention.
6 is a schematic diagram of an embodiment of a laser array system and process according to the present invention.
7 is a schematic diagram of an embodiment of a laser array system and process according to the present invention.
8 is a schematic diagram of an embodiment of a laser fiber bundle arrangement for use in an embodiment of a laser array system according to the present invention.
9 is a schematic diagram of an embodiment of a laser fiber bundle arrangement for use in an embodiment of a laser array system according to the present invention.
10 is a schematic diagram of an embodiment of a laser fiber bundle arrangement for use in an embodiment of a laser array system according to the present invention.
11 is a schematic diagram of an embodiment of a laser fiber bundle arrangement for use in an embodiment of a laser array system according to the present invention.
12 is a schematic diagram of an embodiment of a laser fiber bundle arrangement for use in an embodiment of a laser array system according to the present invention.
13 is a schematic diagram of an embodiment of a laser fiber bundle arrangement for use in an embodiment of a laser array system according to the present invention.
14A is a schematic diagram of an embodiment of a laser fiber bundle arrangement for use in an embodiment of a laser array system in accordance with the present invention.
14B is a schematic diagram of an embodiment of a laser fiber bundle arrangement for use in an embodiment of a laser array system in accordance with the present invention.
14C is a schematic diagram of an embodiment of a laser fiber bundle arrangement for use in an embodiment of a laser array system in accordance with the present invention.
15A is a schematic diagram of an embodiment of a laser fiber bundle arrangement for use in an embodiment of a laser array system in accordance with the present invention.
15B is a schematic diagram of an embodiment of a laser fiber bundle arrangement for use in an embodiment of a laser array system in accordance with the present invention.
16A is a schematic diagram of an embodiment of a laser fiber bundle arrangement for use in an embodiment of a laser array system in accordance with the present invention.
16B is a schematic diagram of an embodiment of a laser fiber bundle arrangement for use in an embodiment of a laser array system in accordance with the present invention.
16C is a schematic diagram of an embodiment of a laser fiber bundle arrangement for use in an embodiment of a laser array system according to the present invention.
16D is a schematic diagram of an embodiment of a laser fiber bundle arrangement for use in an embodiment of a laser array system according to the present invention.

Generally, the present invention relates to combinations of laser beams, systems for making these combinations, and processes using the combined beams. In particular, the present invention relates to arrays, assemblies, and devices for combining laser beams from multiple laser beam sources into one or more combined laser beams. These combined laser beams advantageously preserve the improved and varied aspects and characteristics of the laser beams from the individual sources.

Embodiments of the array assemblies of the present invention and the combined laser beams they provide may find a wide range of applications. Embodiments of the array assembly of the present invention are compact and durable. The array assemblies of the present invention can be used in welding, additive manufacturing including 3-D printing, additive manufacturing-milling systems such as additive and subtractive manufacturing, projection including astronomy, meteorology, imaging, entertainment, dentistry, to name a few. It has applications in medicine, including

Although the focus herein is on blue laser diode arrays, it should be understood that these embodiments are merely illustrative of the types of array assemblies, systems, processes, and combined laser beams contemplated by the present invention. Accordingly, embodiments of the present invention include array assemblies for combining laser beams from various laser beam sources, such as solid state lasers, fiber lasers, semiconductor lasers, as well as other types of lasers and combinations and variations thereof. Embodiments of the present invention are all wavelengths, for example, about 380 nm to about 800 nm (e.g., visible light), about 400 nm to about 880 nm, about 100 nm to about 400 nm, 700 nm to 1 mm, and these It involves combinations of specific wavelengths within a range and combinations of laser beams over transformations. Embodiments of the arrays of the present invention may also find application in microwave coherent radiation (eg, wavelengths greater than about 1 mm). Embodiments of the array of the present invention may combine beams from one, two, three, dozens or hundreds of laser sources. These laser beams can have anywhere from a few milliwatts to watts or even kilowatts.

An embodiment of the present invention preferably consists of an array of blue laser diodes that are combined in a configuration to create a high brightness laser source. This high-brightness laser source can be used to directly process materials, i.e. marking, cutting, welding, soldering, heat treatment, annealing. The material to be processed, eg starting material or target material, may include any material or component or composition, to name but a few semiconductor components such as, but not limited to, TFTs (Thin Film Transistors); 3-D printing starting materials; metals including gold, silver, platinum, aluminum and copper; plastic; tissue; and semiconductor wafers. Direct processing may include the removal of gold from electronics, projection displays and laser light shows, to name a few.

Embodiments of the high brightness laser source of the present invention may also be used to pump Raman lasers or Anti-Stokes lasers. The Raman medium is an optical fiber; or crystals such as diamond, KGW (potassium gadolinium tungstate), KGd(WO ₄ ) ₂ ), YVO ₄ and Ba(NO ₃ ) ₂ . In an embodiment, the high brightness laser source is a blue laser diode source which is a semiconductor device operating in the wavelength range of 400 nm to 500 nm. The Raman medium is a luminance converter and can increase the luminance of a blue laser diode source. Brightness enhancement is a single-mode, diffraction-limited source, that is, any that produces beams with M ² of about 1 and 1.5 with beam parameter products of less than 1, less than 0.7, less than 0.5, less than 0.2, and less than 0.13 mm-mrad, depending on the wavelength. method can be extended.

In embodiments, “n” or “N” (e.g., 2, 3, 4, etc., tens, hundreds, or more) laser diode sources may be used for several laser operations and procedures, including, for example, marking of materials, melting , a bundle of optical fibers enabling an addressable light source that can be used for welding, ablating, annealing, heat treating, cutting, and combinations and modifications thereof.

An array of blue laser diodes can be combined with an optical assembly to create a high brightness direct diode laser system, which can provide a high brightness combined laser beam. 1 shows laser performance (beam parameter product versus W (watts)) for examples of a range of beam parameter products when using fiber combiner technology with a luminance range of 8 mm-mrad at 200 watts to 45 mm-mrad at 4000 watts. It shows a table 100 in terms of laser power in units). Line 101 represents the performance of an embodiment of a laser diode array. Line 102 represents the performance of a high density wavelength beam combining array. Line 103 represents the performance of the luminance conversion technique when scaled using fiber combiner techniques. Line 104 represents the performance of the luminance conversion technique when using a high-density wavelength combination of the luminance converter's output. This causes the combined beam to maintain a single or near single spatial mode as the output level is scaled. Dense wavelength combining uses a grating to control the wavelength of each individual luminance conversion laser and then uses a grating to combine the beams into a single beam. The grating may be a regular grating, a holographic grating, a Fiber Bragg Grating (FBG) or a Volume Bragg Grating (VBG). A preferred embodiment uses a grating, but it is also possible to use a prism.

2A is a schematic diagram of a laser diode 200 propagating a laser beam along the laser beam path to a fast axis collimating lens (FAC) 201 . Cylindrical aspheric lenses of 1.1, 1.2, 1.5, 2 or even 4 mm capture the fast axis output and create a diffraction limited beam on the fast axis at a precise height, preserving brightness and allowing for beam combination further down the optical chain. The collimating lens 202 is for collimating the slow axis of the laser diode (the axis with the smaller divergence angle, typically the x axis). Cylindrical aspheric lenses with focal lengths of 15, 16, 17, 18 or 21 mm capture the output of the slow axis and collimate the slow axis to preserve the brightness of the laser source. The focal length of the slow axis collimator results in an optimal combination of the laser beamlets by the optical system with the target fiber diameter. In a preferred embodiment of the array, slow axis and fast axis collimating lenses are positioned along each laser beam path and used to shape the individual laser beams.

2B is a schematic diagram of a laser beam spot 203 formed by a laser beam from a laser diode passing through both fast and low focus lenses. This simulation considers the maximum divergence of the source over the entire aperture of the source. It is understood that laser beam spots of many different shapes can be created, such as square, rectangular, circular, elliptical, linear, and combinations and variations of these and other shapes. For example, the combined laser beam produces a spot 203 with focused blue laser light at an NA of 0.18, with a spot size of 100 μm for a 100 mm focal length lens.

2C and 2D, a laser diode subassembly 210 (eg, a diode module, bar, plate, multi-die package) and four laser diode assemblies 210, 210a, 210b, 210c An embodiment of a laser diode module 220 is shown.

2E is a detailed view showing portions of several laser beams 250a, 251a, and 252a along their respective laser beam paths 250, 251, and 252. FIG. 2F is a cross-sectional view of the laser beam of FIG. 2E showing open space horizontal 260 and vertical 261 (based on the orientation of the drawing). The beam combining optics spatially close the beams together to remove open spaces (eg, 260, 261) in the final spot 203 (FIG. 2B).

The laser diode module 220 can produce a combined laser beam, preferably a combined blue laser beam, having the performance of curve 101 of FIG. 1 . Laser diode assembly 210 is a thermally conductive material, eg copper, having a power lead (eg wire) (eg 212) that enters to power the diode (eg 213). It has a base plate (211). In this embodiment of the multi-die package, there are 20 laser diodes (eg 213) arranged in a 5x4 configuration behind the cover plate. Other configurations for providing n × n diodes in an assembly, such as 4 × 4, 4 × 6, 5 × 6, 10 × 20, 30 × 5, and those currently in development, and combinations and variations thereof this is taken into account Each diode may have a parallel plate for translating the position of the beam in the slow axis (eg 214) when using a single slow axis collimated (SAC) lens across multiple columns (eg 216). there is. Parallel plates are not needed when using separate slow axis lenses for each laser diode, which is the preferred embodiment. The parallel plates correct the position of the laser beam path in the slow axis as it propagates from each individual laser diode, which may be the result of an assembly process. Parallel plates are not required if separate FAC/SAC lens pairs are used for each laser diode. The SAC location compensates for any assembly errors in the package. The result of all these approaches is to align the beamlets to be collimated when using individual lens pairs (FAC/SAC) or shared SAC lenses after individual FAC/parallel plates, resulting in parallel and spaced apart laser beams (e.g., 251a, 252a). , 250a) and beam paths (eg, 251, 252, 250).

The composite beam from each of the laser diode subassemblies 210, 210a, 210b, 210c is a patterned mirror used to redirect and combine the beams from the four laser diode subassemblies into a single beam, as shown in FIG. 2G. (e.g. 225). Four rows of collimating laser diodes are interlaced with four rows of other three packages to produce composite beams. 2H shows the position of a beam (eg, 230 ) from laser subassembly 210 . Aperture stop 235 clips unwanted scattered light from the combined beamlets, which reduces the thermal load on the fiber input face. Polarization beam folding assembly 227 folds the beam in half on the slow axis to double the brightness of the composite laser diode beam (FIG. 2i). The beam can be folded by splitting the central emitter at the center resulting in the pattern shown in Fig. 2i, where beam 231 is a superposition of two beamlets in the direction of the slow axis by polarization, and beam 232 is arbitrary. It is a split beamlet that does not overlap with other emitters of . If the beam is split between the second and third beamlets ( FIG. 2J ), the beam folder is more efficient and two of the columns of beams (e.g. 233) overlap, while the third column of beams (e.g. 233) , 234) simply passes in a straight line. The telescope assembly 228 expands the combined laser beam on the slow axis or compresses the fast axis to allow the use of smaller lenses. The telescope assembly 228 shown in this example (FIG. 2G) expands the beam by a factor of 2.6, increasing its size from 11 mm to 28.6 mm while reducing the divergence in the slow axis by the same factor of 2.6. When the telescope assembly compresses the fast axis, it shortens the fast axis from 22 mm high (total composite beam) to 11 mm high, resulting in a 2x telescope providing a composite beam measuring 11 mm x 11 mm. This is a preferred embodiment because of its lower cost. An aspheric lens 229 focuses the composite beam into an optical fiber 245 that is at least 50, 100, 150 or 200 μm in diameter. The fiber outputs of multiple laser diode modules 220 are combined with a fiber combiner to produce a high power level laser according to FIG. 1 (line 101). The laser diode module is assembled using an optical combining method in which an aspheric lens 229 and fiber combiner 240 are replaced by an aspheric lens and a set of shear mirrors that are coupled into a composite beam emitted into the ends of the optical fibers. In this way, one, two, three, tens and hundreds of laser diode modules can be optically related and their laser beams can be combined. In this way, the combined laser beams themselves can be additionally or additionally combined to form multiple combined laser beams.

In the embodiment of FIGS. 2C and 2D , the configuration makes it possible to fire a single 50, 100, 150 or 200 μm core fiber, for example, with a laser beam output of up to 200 Watts. This embodiment of FIGS. 2C and 2D is typical for making up to four 50 Watt individual diode assemblies, eg 200 W diode array assemblies using eg 50 Watt modules, eg 200 W combination modules. show the elements

It is understood that the number of configurations, outputs and combined beams is feasible. The embodiment of Figures 2c and 2d minimizes the electrical connection from the power supply to the laser diode.

Thus, individual modules, combination modules, and both may be configured to provide a single combination laser beam or multiple combination laser beams, for example two, three, four, tens, hundreds or more beams. Each of these laser beams can be fired in a single fiber, and they can be further combined and fired in fewer fibers. Thus, as an example, 12 combined laser beams may be fired with 12 fibers, or 12 beams may be combined and fired with less than 12 fibers, for example 10, 8, 6, 4 or 3 fibers. there is. It should be understood that this combination can result in different output beams or beams with different wavelengths or the same wavelength to create a balanced or unbalanced power distribution between the individual fibers.

In an embodiment, the brightness of a laser diode array may be improved by operating each array at a different wavelength and then combining them with a grating or series of narrowband dichroic filters. The luminance scaling of this technique is shown in FIG. 1 as a near-straight line 102 . The starting point is the same luminance as can be achieved by a single module, since each module spatially overlaps the previous one in a linear fashion, the fiber diameter does not change, but the emitted output can achieve a higher luminance from the wavelength beam combining module. cause

In an embodiment, an array of blue laser diodes may be converted to a near single mode or single mode output with the aid of a luminance converter. The luminance converter can be optical fiber, crystal or gas. The conversion process proceeds through Stimulated Raman Scattering, achieved by firing the output from an array of blue laser diodes into an optical fiber or crystal or gas by a resonator cavity. The blue laser diode output is converted into a gain through stimulated Raman scattering, and the laser resonator oscillates at a first Stokes Raman line offset from the pump wavelength by a Stokes shift. See, for example, the embodiment shown in FIG. 3 and related disclosures in the specification of US Patent Application Serial No. 14/787,393 based on WO 2014/179345, the entire disclosure of which is hereby incorporated by reference. The performance characteristics of this technique are shown at line 103 in Fig. 1, where the luminance is at 0.3 mm-mrad for a 200 W laser and 2 for a 4000 W laser when using a fiber combiner to combine multiple high-brightness laser beams. Start at mm-mrad.

The luminance of the blue laser source can be further increased by combining the output of the luminance conversion source. The performance of this type of embodiment is shown by line 104 in FIG. Here, luminance is defined by the starting module at 0.3 mm-mrad. The gain bandwidth of a Raman line is substantially wider than that of a laser diode, so more lasers can be combined across wavelengths than using laser diode technology alone. The result is a 4 kW laser with the same brightness as a 200 W laser or 0.3 mm-mrad. This is indicated by straight line 104 in FIG. 1 .

The inventive technology described herein can be used for a wide range of laser applications ranging from welding, cutting, soldering, heat treatment, shaping, shaping, forming, bonding, annealing and ablation, and combinations thereof, and a variety of other material processing operations. It can be used to configure the system. Although the preferred laser source is relatively high brightness, the present invention provides the ability to configure the system to meet lower brightness requirements. Also, these laser groups can be combined into a long line, which can be used to perform laser operation on large area target materials, such as annealing large area semiconductor devices such as TFTs in flat panel displays, for example.

The outputs of laser diodes, laser diode arrays, wavelength combination laser diode arrays, luminance conversion laser diode arrays and wavelength combination laser diode arrays can be used to create unique, individually addressable printing machines. Because the laser power from each module is sufficient to melt and fuse metal powders as well as plastics, these sources are ideal for additive manufacturing applications as well as additive-subtractive manufacturing applications (i.e., current laser additive manufacturing systems are not compatible with CNC machines). or in combination with laser ablation or ablation as well as conventional ablation fabrication techniques such as other types of milling machines). Because of their ability to provide small spot sizes, precision, and other factors, the systems and laser configurations of the present invention may also find application in micro- and nano-lamination, ablation, and additive-ablation fabrication techniques. Individually coupled laser arrays can be imaged onto the powder surface to create objects at n times the speed of a single scanned laser source. The speed can be further increased by using a higher power laser for each n-spot. When using a luminance conversion laser, near-diffraction-limited spots can be obtained for n spots, making it possible to produce high-resolution parts due to the sub-micron characteristics of individual spots formed by the blue high-brightness laser source. These smaller spot sizes of the present configurations and systems provide significant improvements in printing speed and resolution of the printing process compared to prior art 3D printing techniques. When combined with a portable powder feeder, embodiments of the system of the present invention can continuously print layer after layer at speeds in excess of 100 times the print speed of prior art additive manufacturing machines. By having the system deposit the powder as the positioning device moves in the positive or negative direction directly behind the laser fusion spot (e.g., FIG. 5, powder device 508, powder device 508b), the system can: You can print continuously without having to stop to apply or level the required powder on a layer.

Referring to Figure 3, a schematic diagram of a laser process is shown with a laser system having two rows of staggered spots (eg, 303a and 303b). The laser spot (eg 303a, 303b) is moved, eg scanned, in the direction of arrow 301 across the target material. The target material may be present in output form 302 and then melted by laser spot 304 and then solidified generally along transition line 305 to form fused material 306 . The power of the beam, the ignition time of the beam, the speed of movement, and combinations thereof may be varied in a predetermined manner resulting in a predetermined shape of the melting transition line 305 . The distance over which the beams can be staggered can be 0, 0.1, 0.5, 1, 2 mm intervals as required by the fixtures required to hold the fibers and their optical components. The stagger may also be a monotonically increasing or decreasing position at a set stagger step-size or at a variable step-size. The exact speed advantage will depend on the target material and configuration of the part to be fabricated.

Figure 4 summarizes the performance that can be achieved for embodiments of laser systems and configurations such as those shown in Figures 5-7 for a 20-beam system whose speed increases with each additional beam added to the system. .

Referring to FIG. 5 , a schematic diagram of an embodiment of a laser system having an addressable laser delivery configuration is provided. The system has an addressable laser diode system (501). System 501 provides independently addressable laser beams to a plurality of fibers 502a, 502b, 502c (more and fewer fibers and laser beams are contemplated). The fibers 502a, 502b and 502c are combined into a fiber bundle 504 contained in a protective tube 503 or cover. The fibers 502a, 502b, 502c in the fiber bundle 504 are fused together to form a print head 505 that includes an optical assembly 506 that focuses and directs a laser beam along a beam path to a target material 507. do. The print head and powder hopper move with the movement of the print head in the positive direction according to 510 . Additional material 509 may be placed on top of fusing material 507 with each pass of the print head or hopper. The print head is bi-directional and fuses material in both directions as the print head moves, so a powder hopper operates behind the print head to provide layered material to be fused in the next pass of the laser printing head.

"Addressable array" means one or more of the following: an output; ignition period; ignition sequence; ignition position; beam output; The shape of the beam spot as well as the focal length, for example the depth of penetration in the z-direction, can be independently varied, controlled and predetermined, or each laser beam in each fiber can be converted from a target material to a very precise final product (e.g. For example, providing a precise, predetermined delivery pattern from which a build material can be created Embodiments of addressable arrays may also be used to perform various, predetermined and precise laser operations such as annealing, ablation, and melting. It has the capability for individual beams and laser stops created by these beams.

Referring to FIG. 6 , a schematic diagram of an embodiment of a laser system having an addressable laser delivery configuration is provided. The laser system may be a laser diode array system, a luminance conversion system or a high power fiber laser system. The system has an addressable laser system 601. System 601 provides independently addressable laser beams to a plurality of fibers 602a, 602b, 602c (more and fewer fibers and laser beams are contemplated). The fibers 602a, 602b and 602c are combined into a fiber bundle 604 contained within a protective tube 603 or cover. The fibers 602a, 602b, and 602c in the fiber bundle 604 are fused together to form a printing head 605 that includes an optical assembly 606 that focuses and directs a laser beam along a beam path to a target material 607. do. Target material 607 is annealed to form annealed material 609 . The direction of movement of the laser head is shown by arrow 610 .

Referring to FIG. 7 , a schematic diagram of an embodiment of a laser system having an addressable laser delivery configuration is provided. The system has an addressable laser diode system 701. The system 701 provides independently addressable laser beams to a plurality of fibers 702a, 702b, 702c (more and fewer fibers and laser beams are contemplated). The fibers 702a, 702b and 702c are combined into a fiber bundle 704 contained within a protective tube 703 or cover. Fibers 702a, 702b, 702c in fiber bundle 704 are fused together to form print head powder dispensing head 720. The powder dispensing head 720 can have the powder delivered coaxially to the laser beam or transversely to the laser beam. The powder dispensing head 720 provides an additional layer of material 709 that is fused to and on top of the target material 707 . The direction of movement of the laser head is shown by an arrow 710.

FIG. 8 shows the configuration of a bundle 800 of fibers (e.g., 801) that are fused together and used in a laser head of a system such as the system shown in FIGS. 5-7. The configuration will deliver a laser spot configured similarly to a fiber array. In this embodiment, there are 5 fibers in a single linear row, a 1 x 5 linear configuration. A 1 x n linear row of fibers is the final laser print head. where n depends on the physical extent of the product to be printed.

FIG. 9 shows the configuration of a bundle 900 of fibers (e.g., 901) that are fused together and used in a laser head of a system such as the system shown in FIGS. 5-8. The configuration has two linear rows 902, 903 of fibers that are staggered and arranged in a rhomboid arrangement. The fiber will deliver a laser spot configured similarly to a fiber array. In this embodiment, there are two rows of 5 fibers in each linear row, a 2 x 5 linear configuration.

FIG. 10 shows the configuration of a bundle 1000 of fibers (e.g., 1001) that are fused together and used in a laser head of a system such as the system shown in FIGS. 5-8. This configuration has three linear rows 1002, 1003, 1004 of fibers arranged in a staggered and rhomboidal arrangement. The fiber will deliver a laser spot configured similarly to a fiber array. In this embodiment, there are three rows of 5 fibers in each linear row, a 3 x 5 linear configuration.

FIG. 11 shows the configuration of a bundle 1100 of fibers (e.g., 1101) that are fused together and used in a laser head of a system such as the system shown in FIGS. 5-8. This configuration has three linear rows 1102, 1103, 1104 of fibers arranged in a staggered and triangular arrangement. The fiber will deliver a laser spot configured similarly to a fiber array. In this embodiment, there are three rows of 5 fibers in each linear row, a 3 x 5 linear configuration.

FIG. 12 shows the configuration of a bundle 1200 of fibers (e.g., 1201) that are fused together and used in a laser head of a system such as the system shown in FIGS. 5-8. This configuration has four linear rows 1202, 1203, 1204, 1205 of fibers arranged in a non-staggered and square arrangement. The fiber will deliver a laser spot configured similarly to a fiber array. In this embodiment, there are four rows of four fibers in each linear row, a 4x4 linear configuration.

FIG. 13 shows the configuration of a bundle 1300 of fibers (e.g., 1301) that are fused together and used in a laser head of a system such as the system shown in FIGS. 5-8. This configuration has 5 linear columns (eg 1302). The fibers are arranged in a square arrangement rather than staggered. The fiber will deliver a laser spot configured similarly to a fiber array. In this embodiment, there are 5 rows of 4 fibers in each linear row, a 5 x 5 linear configuration.

14A shows the configuration of a bundle 1401 of five (n = 5) fibers (e.g., 1401) arranged in a circular configuration.

14B shows the configuration of a bundle 1402 of nine (n = 9) fibers (eg, 1402a) arranged in a circular configuration with fiber 1402b located at the center of the circle. The central fibers 1402b will either be held in place by a medium or holding device or will be fused together.

14C shows the configuration of a bundle 1403 of 19 (n = 19) fibers (eg, 1403a) with an inner circle of fibers 1405 and a central fiber 1403b.

15A shows a bundle 1501 of seven (n = 7) fibers (eg 1501a) having a hexagonal arrangement with triangular spacing.

15B shows a bundle 1502 of 19 (n=19) fibers (eg, 1502a) having a hexagonal arrangement with triangular spacing.

Figures 16a, 16b and 16c show configurations of fiber bundles arranged in arbitrary geometric arrangements. These configurations provide varying levels of fiber density in the configuration. 16A is an n=16 bundle 1601 of fibers (eg, 1601a) in a quadrant configuration. 16B is an n = 8 bundle 1602 of fibers (eg 1602b) in a square configuration. 16C is an n=6 bundle 1604 of fibers (eg, 1604a) in a triangular configuration. 16D is an n = 9 bundle 1603 of fibers (eg, 1603a) in a semicircular configuration.

The following examples are provided to illustrate various embodiments of laser arrays, systems, devices and methods of the present invention. These examples are for illustrative purposes and should not be considered as, nor otherwise limiting, the scope of the invention.

Example 1

An array of blue laser diodes that are spatially combined to create a single spot in the far field, which can be coupled to a solarization resistant optical fiber for delivery to the workpiece.

Example 2

An array of blue laser diodes as described in Example 1, which are polarized beams that combine to increase the effective brightness of the laser beam.

example 3

In the fast axis of the laser diodes which are later combined with the periodic plate, reflecting the first laser diode(s) and directing the second laser diode(s) to fill the space between the laser diodes in the fast direction of the first array. An array of blue laser diodes with a space between each collimated beam.

example 4

A patterned mirror on a glass substrate used to achieve the space fill of Example 3.

Example 5

With the patterned mirror on one side of the glass substrate to achieve the space filling of Example 3, the glass substrate is thick enough to shift the vertical position of each laser diode to fill the empty space between the individual laser diodes.

Example 6

A stepped heat sink that achieves the space fill of Example 3 and is a patterned mirror as described in Example 4.

Example 7

An array of blue laser diodes as described in Example 1, where each individual laser is set at a different wavelength by an external cavity to substantially increase the brightness of the array to the equivalent brightness of a single laser diode source.

example 8

An array of blue laser diodes as described in Example 1, wherein the individual arrays of laser diodes are fixed to a single wavelength using external cavities based gratings, and each array of laser diodes is fixed to a single wavelength using tightly spaced optical filters or gratings. combined into beams.

Example 9

An array of blue laser diodes as described in Example 1, which is used to pump a Raman converter such as an optical fiber having a pure fused silica core to create a high brightness source and a fluorinated outer core to contain the blue pump light.

Example 10

An array of blue laser diodes as described in Example 1 comprising an optical fiber having a GeO ₂ doped central core for the outer core and an outer core larger than the central core to contain the blue pump light to create a high brightness source. The same Raman transducer is used for pumping.

Example 11

An array of blue laser diodes as described in Example 1, which is a Raman like optical fiber having a P ₂ O ₅ doped central core to create a high brightness source and an outer core larger than the central core to contain blue pump light. It is used to pump the transducer.

Example 12

An array of blue laser diodes as described in Example 1, with a graded index core to create a high brightness source and a Raman converter such as an optical fiber having an outer core larger than the central core to contain the blue pump light. used to do

Example 13

An array of blue laser diodes as described in Example 1, which is used to pump a Raman converter with a graded index GeO ₂ doped core and an external stepped index core.

Example 14

An array of blue laser diodes as described in Example 1, which is used to pump a Raman converter with a graded index P ₂ O ₅ doped core and an external stepped index core.

Example 15

An array of blue laser diodes as described in Example 1, which is used to pump a graded color GeO ₂ doped core Raman converter.

Example 16

An array of blue laser diodes as described in Example 1, which is used to pump a Raman converter fiber with a graded index P ₂ O ₅ doped core and an outer stepped index core.

Example 17

Other embodiments and variations of the embodiment of Example 1 are contemplated. An array of blue laser diodes as described in Example 1 is used to pump a diamond-like Raman transducer to create a high brightness laser source. An array of blue laser diodes as described in Example 1 is used to pump a Raman converter such as a KGW to create a high brightness laser source. An array of blue laser diodes as described in Example 1 is used to pump a Raman converter such as YVO ₄ to create a high brightness laser source. An array of blue laser diodes as described in Example 1 is used to pump a Raman converter such as Ba(NO ₃ ) ₂ to create a high brightness laser source. An array of blue laser diodes as described in Example 1 is used to pump a high-pressure gas, Raman converter, to create a high-brightness laser source. An array of blue laser diodes as described in Example 1 is used to pump a rare earth doped crystal to create a high brightness laser source. An array of blue laser diodes as described in Example 1 is used to pump a rare earth doped fiber to create a high brightness laser source. An array of blue laser diodes as described in Example 1 is used to pump the outer core of the luminance converter to produce a higher percentage luminance enhancement.

Example 18

An array of Raman converted lasers operated at individual wavelengths and combined to create a high power source while preserving the spatial luminance of the original source.

Example 19

dual core; and a Raman fiber having means for suppressing the second-order Raman signals in the high-brightness central core using filters, fiber Bragg gratings, first- and second-order Raman signals of V order, or micro-bend loss differences.

Example 20

N (N ≥ 1) laser diodes that can be individually turned on and off and can be imaged onto a powder bed to melt and fuse the powder into unique parts.

Example 21

The array of N (N ≥ 1) laser diodes of Example 1, the output of which can be fiber-coupled and each fiber is imaged or focused on a powder to melt and fuse the powder into a unique layer-by-layer geometry. can be arranged in a linear or non-linear fashion to create an addressable array of

Example 22

An array of one or more laser diodes that are combined via a Raman transducer, the output of which can be fiber-coupled and each fiber imaged or focused on a powder such that it melts and fuses the powder into a unique layer-by-layer geometry such that N (N ≥ 1 ) can be arranged in a linear or non-linear fashion to create an addressable array of high power laser beams.

Example 23

An x-y motion system capable of transporting N (N ≥ 1) blue laser sources across the powder bed while melting and fusing the powder bed, with a powder delivery system located behind the laser source to provide a new powder layer after the fusing layer. do.

Example 24

A z-motion system capable of increasing/decreasing the height of the part/powder bed of Example 20 after a new layer of powder is placed.

Example 25

The z-motion system can increase/decrease the height of the part/powder bed of Example 20 after the powder layer has been fused by the laser source.

Example 26

The bi-directional powder placement capability for example 20 places the powder directly behind the laser spot(s) as it moves in either the positive or negative x direction.

Example 27

The bi-directional powder placement capability for example 20 places the powder directly behind the laser spot(s) as it moves in the positive or negative y direction.

Example 28

A powder feeding system coaxial with N (N ≥ 1) laser beams.

Example 29

A powder feeding system in which the powder is fed by gravity.

Example 30

A powder feeding system in which the powder is entrained in an inert gas flow.

Example 31

A powder supply system transverse to N (N≧1) laser beams, where the powder is gravitationally placed directly in front of the laser beams.

Example 32

A powder supply system transverse to N (N≧1) laser beams, wherein the powder is entrained in an inert gas intersecting the laser beams.

Example 33

Generates light at half the wavelength of the source laser or at 230 nm made of an externally resonating crystal such as KTP, but using the output of a Raman converter e.g. at 460 nm to not allow short wavelength light to propagate through the fiber. second harmonic generation system.

Example 34

A third harmonic generation system that uses an externally resonant double crystal to generate light at 115 nm, but uses the output of a Raman converter, for example at 460 nm, to not allow short-wavelength light to propagate through an optical fiber.

Example 35

A fourth harmonic generation system that uses an externally resonant double crystal to generate light at 57.5 nm but uses the output of a Raman converter, for example at 460 nm, to not allow short-wavelength light to propagate through an optical fiber.

Example 36

Using an externally resonant double crystal to generate light at half the wavelength of the source laser or at 236.5 nm but when pumped by an array of blue laser diodes at 450 nm to not allow short wavelength light to propagate through the fiber. A second harmonic generation system using the output of a rare earth doped luminance converter such as thulium that fires a laser at 473 nm.

Example 37

It uses an externally resonating double crystal to generate light at 118.25 nm, but thulium that fires a laser at 473 nm when pumped by an array of blue laser diodes at 450 nm to not allow short wavelength light to propagate through the fiber. A third harmonic generation system using the output of a rare earth doped luminance converter such as

Example 38

It uses an externally resonant double crystal to generate light at 59.1 nm, but thulium that fires a laser at 473 nm when pumped by an array of blue laser diodes at 450 nm to not allow short wavelength light to propagate through the fiber. A fourth harmonic generation system using the output of a rare earth doped luminance converter such as

Example 39

All other rare earth doped fibers and crystals that can be pumped by a high power 450 nm source to generate visible or near-visible light output can be used in Examples 34-38.

yes 40

Firing of high power visible light into a non-circular outer core or clad to pump the inner core of a Raman or rare earth doped core fiber.

yes 41

Use of a polarization maintaining fiber to enhance the gain of a Raman fiber by aligning the polarization of a pump with that of a Raman oscillator.

Example 42

An array of blue laser diodes as described in Example 1, which is used to pump a Raman transducer such as an optical fiber structured to create a higher luminance source of a specific polarization.

Example 43

An array of blue laser diodes as described in Example 1, which is used to create a higher luminance source of a specific polarization and pump a Raman transducer such as an optical fiber structured to maintain the polarization state of the pumping source.

Example 44

An array of blue laser diodes as described in Example 1, which is used to pump a Raman converter such as an optical fiber to create a higher luminance source with a non-circular outer core structured to improve Raman conversion efficiency.

Example 45

The embodiments of examples 1-44 may also include one or more of the following components or assemblies: a device that flattens the powder at the end of each pass before the laser is scanned over the powder bed; an apparatus for scaling the power of a laser by combining multiple low power laser modules through a fiber combiner to produce a high power beam; a device for scaling the output power of a blue laser module by combining multiple low power laser modules through free space to produce a high power beam; It may include devices that combine multiple laser modules into a single baseplate using embedded cooling.

It should be noted that it is not necessary to present or address the theory underlying the subject matter of the embodiments of the present invention or new and breakthrough performance or other advantageous features and characteristics related thereto. Nevertheless, various theories are provided herein to further advance the technology in this important area, particularly in the important areas of lasers, laser processing and laser applications. These theories are presented herein and in no way limit, limit or narrow the scope of protection afforded by the claimed invention unless otherwise specified. These theories may not be required or practiced in order to use the invention. The present invention may lead to new and hitherto unknown theories for explaining the operation, function and characteristics of embodiments of the methods, articles, materials, apparatus and systems of the present invention, such recently developed theories that the present invention It is further understood that it does not limit the scope of protection provided.

The various embodiments of lasers, diodes, arrays, modules, assemblies, acts and operations described herein may be used in the fields identified above and in a variety of other fields. In addition, these embodiments may include, for example, existing lasers, additive manufacturing systems, operations, and behaviors as well as other existing equipment; future lasers, additive manufacturing systems, operation and conduct; and with such articles that may be modified in part based on the teachings herein. Further, the various embodiments described herein can be used with each other in different and various combinations. Thus, for example, components provided in various embodiments of this specification may be used in conjunction with each other, and the scope of protection provided by the present invention is a specific embodiment, configuration or arrangement described in a specific embodiment, example or embodiment of specific drawings. should not be limited to

The present invention may be embodied in other forms than those specifically disclosed herein without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and non-limiting.

Claims (62)

A laser system for performing laser operation, comprising:
a. a plurality of laser diode assemblies;
b. each laser diode assembly having a plurality of laser diodes capable of producing individual blue laser beams along a laser beam path;
c. means for spatially combining the individual blue laser beams to create a combined laser beam having a single spot in the far field that can be coupled to an optical fiber for delivery to a target material; and
d. means for spatially combining the individual blue laser beams onto the laser beam path and in optical relationship with each laser diode;
A laser system for performing laser operations. According to claim 1,
at least three laser diode assemblies; Each laser diode assembly includes at least 30 laser diodes; The laser diode assembly is capable of propagating a laser beam having a total power of at least about 30 Watts and beam parameter characteristics of less than 20 mm mrad.
A laser system for performing laser operations. According to claim 2,
The beam parameter characteristic is less than 15 mm mrad
A laser system for performing laser operations. According to claim 2,
The beam parameter characteristic is less than 10 mm mrad
A laser system for performing laser operations. According to claim 1,
The spatially combining means produces a combined laser beam of N times the luminance of the individual laser beams, where N is the number of laser diodes in the laser diode assembly.
A laser system for performing laser operations. According to claim 5,
The means for spatially combining increases the power of the laser beam while preserving the luminance of the combined laser beam; The combined laser beam has a power that is at least 50 times the power of the individual laser beams and the beam parameter product of the combined laser beam is less than twice the beam parameter product of the individual laser beams.
A laser system for performing laser operations. According to claim 6,
The beam parameter product of the combined laser beam is less than or equal to 1.5 times the beam parameter product of the individual laser beams.
A laser system for performing laser operations. According to claim 6,
The beam parameter product of the combined laser beam is less than or equal to 1 times the beam parameter product of the individual laser beams.
A laser system for performing laser operations. According to claim 5,
The spatially combining means increases the power of the laser beams while preserving the luminance of the individual laser beams; The combined laser beam has a power that is at least 100 times the power of the individual laser beams and the beam parameter product of the combined laser beam is less than twice the beam parameter product of the individual laser beams.
A laser system for performing laser operations. According to claim 9,
The beam parameter product of the combined laser beam is less than or equal to 1.5 times the beam parameter product of the individual laser beams.
A laser system for performing laser operations. According to claim 7,
The beam parameter product of the combined laser beam is less than or equal to 1 times the beam parameter product of the individual laser beams.
A laser system for performing laser operations. According to claims 1, 2 and 6,
The optical fiber is solarization resistant
A laser system for performing laser operations. According to claims 1, 2 and 6,
wherein the spatially combining means comprises an assembly selected from the group consisting of parallel alignment plates and wedges for correcting at least one of a position error or orientation error of the laser diode.
A laser system for performing laser operations. According to claims 1, 2 and 6,
The spatially combining means comprises a deflecting beam combiner capable of increasing the effective brightness of the combined laser beams over individual laser beams.
A laser system for performing laser operations. According to claims 1, 2 and 6,
The laser beam assembly defines an individual laser beam path with respect to the space between the respective paths, so that the individual laser beam has a space between each beam, and the spatially combining means comprises an individual laser beam on the fast axis of the laser diode. A collimator for collimating the beam and a periodic mirror for combining the collimated laser beam, the periodic mirror reflecting a first laser beam from a first diode in the laser diode assembly and reflecting a beam from a second diode in the laser diode assembly. configured to deliver a second laser beam, wherein the space between the individual laser beams is filled in a high-velocity direction.
A laser system for performing laser operations. According to claim 1,
The spatially combining means comprises a patterned mirror on a glass substrate.
A laser system for performing laser operations. 17. The method of claim 16,
The glass substrate is of sufficient thickness to divert the vertical position of the laser beam from the laser diodes to fill the empty space between the laser diodes.
A laser system for performing laser operations. According to claim 1,
Including a stepped heat sink
A laser system for performing laser operations. A laser system for providing a high-brightness, high-power laser beam,
a. a plurality of laser diode assemblies;
b. Each laser diode assembly including a plurality of laser diodes capable of generating a blue laser beam having an initial luminance, and
c. means for spatially combining blue laser beams to produce a combined laser beam having a final luminance and forming a single spot at a distance that can be coupled to an optical fiber;
d. each laser diode is fixed by an external cavity to a different wavelength to substantially increase the luminance of the combined laser beam, so that the final luminance of the combined laser beam is approximately equal to the initial luminance of the laser beam from the laser diode;
A laser system for providing a high-brightness, high-power laser beam. According to claim 19,
Each laser diode is fixed to a single wavelength using an external cavity based grating and each laser diode assembly is combined into a combined beam using a combining means selected from the group consisting of a grating and a narrowly spaced optical filter.
A laser system for providing a high-brightness, high-power laser beam. A laser system for performing laser operation, comprising:
a. a plurality of laser diode assemblies;
b. Each laser diode assembly including a plurality of laser diodes capable of producing a blue laser beam along a laser beam path, and
c. comprising means for spatially combining blue laser beams to create a combined laser beam having a remote single spot that can be optically coupled to a Raman converter, pumped to the Raman converter, and increasing the brightness of the combined laser beam. doing
A laser system for performing laser operations. According to claim 21,
The Raman converter is an optical fiber having a pure fused silica core for creating a high brightness source and a fluorinated outer core containing blue pump light.
A laser system for performing laser operations. According to claim 21,
The Raman converter is used to pump a Raman converter such as an optical fiber having a GeO ₂ doped central core with an outer core and an outer core larger than the central core containing blue pump light to create a high brightness source.
A laser system for performing laser operations. According to claim 21,
The Raman converter is an optical fiber having a P ₂ O ₂ doped core to create a high brightness source and an outer core larger than the central core to contain blue pump light.
A laser system for performing laser operations. According to claim 21,
The Raman converter is an optical fiber having a graded index core to create a high brightness source and an outer core larger than the central core to contain blue pump light.
A laser system for performing laser operations. According to claim 21,
The Raman converter is a graded GeO ₂ doped core and an external stepped index core.
A laser system for performing laser operations. According to claim 21,
The Raman converter is used to pump a Raman converter fiber, which is a graded P ₂ O ₂ doped core and an outer stepped index core.
A laser system for performing laser operations. According to claim 21,
The Raman converter is used to pump a Raman converter fiber that is a graded GeO ₂ doped core.
A laser system for performing laser operations. According to claim 21,
The Raman converter is a graded index P ₂ O ₂ doped core and an external stepped index core.
A laser system for performing laser operations. According to claim 21,
The Raman converter is a diamond generating a high-brightness laser source.
A laser system for performing laser operations. According to claim 21,
The Raman converter is a KGW that generates a high-brightness laser source
A laser system for performing laser operations. According to claim 21,
The Raman converter is YVO ₄ to generate a high-brightness laser source
A laser system for performing laser operations. According to claim 21,
The Raman converter is Ba(NO ₃ ) ₂ to generate a high-brightness laser source.
A laser system for performing laser operations. According to claim 21,
The Raman converter is a high-pressure gas that generates a high-brightness laser source.
A laser system for performing laser operations. As a method for producing a combined laser beam,
operating an array of Raman converted lasers to generate blue laser beams and combined laser beams at individual different wavelengths to create a high power source while preserving the spatial luminance of the original source.
A method of manufacturing a combined laser beam. A laser system for performing laser operation, comprising:
a. a plurality of laser diode assemblies;
b. Each laser diode assembly including a plurality of laser diodes capable of generating a blue laser beam along a laser beam path;
c. Beam aiming and combining optics along the laser beam path, to which a collimated laser beam can be provided, and
d. comprising an optical fiber for receiving the combined laser beam.
A laser system for performing laser operations. 37. The method of claim 36,
The optical filter is in optical communication with the rare earth doped fiber so that the combined laser beam can pump the rare earth doped fiber to create a high brightness laser source.
A laser system for performing laser operations. 37. The method of claim 36,
The optical fiber is in optical communication with the outer core of the high brightness converter so that the combined laser beam can pump the outer core of the brightness converter to produce a higher percentage brightness enhancement.
A laser system for performing laser operations. As a Raman fiber,
dual cores, one of which is a high-brightness central core; and
means for suppressing secondary Raman signals in the high brightness central core selected from the group consisting of filters, fiber Bragg gratings, first and second order Raman signals of order V, and micron bend loss differences;
Raman fibers. As a second harmonic generation system,
a Raman converter of a first wavelength for generating light at half the wavelength of the first wavelength; and
An external resonant double crystal configured to prevent half-wavelength light from propagating through an optical fiber.
Second harmonic generation system. 41. The method of claim 40,
The first wavelength is about 460 nm, and the external resonant double crystal is KTP.
Second harmonic generation system. As a third harmonic generation system,
a Raman converter of a first wavelength for generating light at a second wavelength lower than the first wavelength; and
An external resonant double crystal configured to prevent lower wavelength light from propagating through the optical fiber.
Third harmonic generation system. As a fourth harmonic generation system,
A Raman converter that generates light at 57.5 nm using an external resonant double crystal configured to prevent 57.5 nm wavelength light from propagating through an optical fiber.
4th harmonic generation system. As a second harmonic generation system,
A laser at 473 nm when pumped by an array of blue laser diodes at 450 nm to generate light at half the wavelength of the source laser, or 236.5 nm, using an externally resonant double crystal that does not allow short-wavelength light to propagate through the fiber. A rare earth doped luminance converter containing thulium firing a
Second harmonic generation system. As a third harmonic generation system,
contains thulium which does not allow short wavelength light to propagate through the fiber but fires a laser at 473 nm when pumped by an array of blue laser diodes at 450 nm to generate light at 118.25 nm using an externally resonant double crystal Including a rare earth doped luminance converter
Third harmonic generation system. As a fourth harmonic generation system,
contains thulium which does not allow short wavelength light to propagate through the fiber but fires a laser at 473 nm when pumped by an array of blue laser diodes at 450 nm to generate light at 59.1 nm using an externally resonant double crystal Including a rare earth doped luminance converter
4th harmonic generation system. According to claim 21,
The Raman converter includes a non-circular outer core structured to improve Raman conversion efficiency.
A laser system for performing laser operations. A laser system for performing laser operation, comprising:
a. at least three laser diode assemblies;
b. At least a laser diode assembly, each comprising at least 10 laser diodes, each of the at least 10 laser diodes producing a blue laser beam along a laser beam path with a power of at least about 2 Watts and a beam parameter product of less than 8 mm-mrad. capable of at least a laser diode assembly, and
c. A means for spatially combining and preserving the luminance of a blue laser beam, all located in at least 30 laser beam paths, comprising: collimating optics for a first axis of the laser beam, a vertical prism array for a second axis of the laser beam, and a telescope. and means for providing a combined laser beam with a power of at least about 600 Watts and a beam parameter product of less than 40 mm-mrad by filling the space between the laser beams with laser energy.
A laser system for performing laser operations. As an addressable array laser processing system,
comprising the at least three laser systems of claim 67 and a control system;
Each of the at least three laser systems is configured to couple each of their combined laser beams to a single optical fiber so that each of the at least three combined laser beams can be propagated along its coupled optical fiber, wherein the at least three optical fibers are a laser optically associated with the head, wherein the control system includes a program having a predetermined sequence for delivering each of the combined laser beams to a predetermined location on the target material.
Addressable array laser processing system. 50. The method of claim 49,
The predetermined sequence for delivery includes individually turning on and off the laser beam from the laser head to image the target material, including the powder, onto the powder bed to melt and fuse it into the part.
Addressable array laser processing system. 50. The method of claim 49,
The fibers in the laser head are configured in an arrangement selected from the group consisting of linear, non-linear, circular, rhomboidal, square, triangular, and hexagonal.
Addressable array laser processing system. 50. The method of claim 49,
The fibers in the laser head are configured in an array selected from the group consisting of 2x5, 5x2, 4x5, at least 5x at least 5, 10x5, 5x10 and 3x4.
Addressable array laser processing system. 50. The method of claim 49,
The target material includes a powder bed, an xy motion system capable of moving a laser head across the powder bed to melt and fuse the powder bed, and a powder positioned behind the laser source to provide a new powder layer behind the fused layer. containing delivery system
Addressable array laser processing system. 54. The method of claim 53,
A z-motion system capable of moving the laser head to increase and decrease the height of the laser head above the surface of the powder bed.
Addressable array laser processing system. 54. The method of claim 53,
A bi-directional powder placement device capable of placing the powder directly behind the delivered laser beam as it moves in the positive x direction or the negative x direction.
Addressable array laser processing system. 54. The method of claim 53,
A powder supply system coaxial with a plurality of laser beam paths.
Addressable array laser processing system. 54. The method of claim 53,
Including gravity feed powder system
Addressable array laser processing system. 54. The method of claim 53,
a powder supply system in which the powder is entrained in an inert gas flow;
Addressable array laser processing system. 54. The method of claim 53,
A powder supply system transverse to the N(N≥1) laser beam, wherein the powder is gravitationally placed in front of the laser beam.
Addressable array laser processing system. 54. The method of claim 53,
A powder supply system transverse to the N(N≥1) laser beam, wherein the powder is entrained in an inert gas flow intersecting the laser beam.
Addressable array laser processing system. A method for providing a combined blue laser beam with high brightness, comprising:
operating a plurality of Raman conversion lasers to provide a plurality of individual blue laser beams; and
combining the individual blue laser beams to create a high power source while preserving the spatial luminance of the original source;
The plurality of individual laser beams have different wavelengths.
A method for providing a combined blue laser beam with high brightness. As a method of laser processing a target material,
operating an addressable array laser processing system comprising at least three laser systems of claim 10 to generate individual laser beams combined into three individual optical fibers;
passing each combined laser beam to a laser head along its optical fiber; and
directing the combined three individual laser beams from the laser head in a predetermined order at a predetermined location on the target material.
A method of laser processing a target material.

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