Methods of and systems for processing using adjustable beam characteristics

Abstract

A method of processing by controlling one or more beam characteristics of an optical beam may include: launching the optical beam into a first length of fiber having a first refractive-index profile (RIP); coupling the optical beam from the first length of fiber into a second length of fiber having a second RIP and one or more confinement regions; modifying the one or more beam characteristics of the optical beam in the first length of fiber, in the second length of fiber, or in the first and second lengths of fiber; confining the modified one or more beam characteristics of the optical beam within the one or more confinement regions of the second length of fiber; and/or generating an output beam, having the modified one or more beam characteristics of the optical beam, from the second length of fiber. The first RIP may differ from the second RIP.

1 - 20 . (canceled) 
     
     
         21 . A method of fabricating an object, the method comprising:
 processing a powder bed or work piece with a laser in which optical power is delivered from the laser to the powder bed or work piece via an optical fiber using beam characteristic variations carried out in-fiber without the use of free space optics, wherein the optical power is delivered from the laser using a scan pattern including a plurality of individual passes and the processing includes:
 performing at least part of an individual pass of the plurality of individual passes using a first output beam emitted from the optical fiber; 
 after performing the at least part of the individual pass, modifying one or more beam characteristics of an optical beam launched into the optical fiber to generate a second output beam; and 
 performing a next part of the individual pass or at least part of a next individual pass of the plurality of individual passes using the second output beam. 
   
     
     
         22 . The method of  claim 21 , further comprising using the first output beam to pre-heat powder of the powder bed prior to fusing the powder and using the second output beam to fuse the powder. 
     
     
         23 . The method of  claim 21 , further comprising using the first output beam to pre-heat powder of the powder bed prior to fusing the powder and using the output beam to post-heat the fused powder. 
     
     
         24 . The method of  claim 21 , further comprising using the first output beam to fuse powder of the powder bed and using the second output beam to post-heat the fused powder. 
     
     
         25 . The method of  claim 21 , further comprising:
 using the first output beam to pre-heat powder of the powder bed prior to fusing the powder;   using the second output beam to fuse the powder; and   using the second output beam to post-heat the fused powder.   
     
     
         26 . The method of  claim 21 , further comprising:
 using a first portion of one of the output beams to pre-heat powder of the powder bed prior to fusing the powder, and simultaneously using a second portion of the same output beam to fuse the powder.   
     
     
         27 . The method of  claim 21 , further comprising:
 using a first portion of one of the output beams to fuse powder of the powder bed, and simultaneously using a second portion of the same output beam to post-heat the fused powder.   
     
     
         28 . The method of  claim 21 , further comprising:
 using a first portion of one of the output beams to pre-heat powder of the powder bed prior to fusing the powder, and simultaneously using the first portion of the same output beam to post-heat the fused powder.   
     
     
         29 . The method of  claim 21 , further comprising:
 using a first portion of one of the output beams to pre-heat powder of the powder bed prior to fusing the powder;   simultaneously using a second portion of the same output beam to fuse the powder; and   simultaneously using the first portion of the same output beam to post-heat the fused powder.   
     
     
         30 . The method of  claim 21 , wherein fabricating the object comprises using one of the output beams for one or more of cladding, cutting, drilling, engraving, glazing, heat-treating, marking, patterning, roughening, smoothing, surface texturing, trepanning, or welding, or combinations thereof, one or more parts of the object. 
     
     
         31 . An apparatus to fabricate an object from a powder bed or work piece, the apparatus comprising:
 a laser system in which optical power is delivered from the laser system to the powder bed or work piece via an optical fiber using beam characteristic variations carried out in-fiber, the laser system comprising:
 a variable beam characteristic (VBC) fiber assembly to carry out the beam characteristics variations in-fiber, the VBC fiber assembly to generate, from an optical beam provided thereto, an adjusted beam having variable beam characteristics, without the use of free-space optics; 
 a free-space optics assembly coupled to an output of the VBC fiber assembly, the free-space optics assembly to perform one or more optical manipulations on the adjusted beam; and 
 a process head coupled to an output of the free-space optics assembly to receive the adjusted beam or an optical beam derived therefrom, the process head to deliver optical power from the laser system to the powder bed or workpiece using a scan pattern including a plurality of individual passes. 
   
     
     
         32 . The apparatus of  claim 31 , wherein the one or more optical manipulations change the variable beam characteristics of the adjusted beam. 
     
     
         33 . The apparatus of  claim 32 , wherein the one or more optical manipulations change a divergence, beam diameters, and/or spot size of the adjusted beam. 
     
     
         34 . The apparatus of  claim 31 , wherein the one or more optical manipulations preserve the variable beam characteristics of the adjusted beam. 
     
     
         35 . The apparatus of  claim 31 , wherein the VBC fiber assembly generates the adjusted beam differently for one of the individual passes than another one or the individual passes, or the VBC fiber assembly generates the adjusted beam differently for an initial part of the one of the individual passes than a subsequent part of the one of the individual passes. 
     
     
         36 . An apparatus for fabricating an object, the apparatus comprising:
 a laser system to process a powder bed or work piece with a laser in which optical power is delivered from the laser to the powder bed or work piece via an optical fiber using beam characteristic variations carried out in-fiber without the use of free space optics, wherein the optical power is delivered from the laser using a scan pattern including a plurality of individual passes and the laser system includes:
 means for performing at least part of an individual pass of the plurality of individual passes using a first output beam emitted from the optical fiber; 
 means for modifying one or more beam characteristics of an optical beam launched into the optical fiber to generate a second output beam after performing the at least part of the individual pass; and 
 means for performing a next part of the individual pass or at least part of a next individual pass of the plurality of individual passes using the second output beam. 
   
     
     
         37 . The apparatus of  claim 36 , further comprising means for using the first output beam to pre-heat powder of the powder bed prior to fusing the powder and means for using the second output beam to fuse the powder. 
     
     
         38 . The apparatus of  claim 36 , further comprising means for using the first output beam to pre-heat powder of the powder bed prior to fusing the powder and means for using the output beam to post-heat the fused powder. 
     
     
         39 . The apparatus of  claim 36 , further comprising means for using the first output beam to fuse powder of the powder bed and means for using the second output beam to post-heat the fused powder. 
     
     
         40 . The apparatus of  claim 36 , further comprising:
 means for using the first output beam to pre-heat powder of the powder bed prior to fusing the powder;   means for using the second output beam to fuse the powder; and   means for using the second output beam to post-heat the fused powder.