Abstract: Disclosed herein are methods, apparatus, and systems for providing an optical beam delivery system, comprising an optical fiber including a first length of fiber comprising a first RIP formed to enable, at least in part, modification of one or more beam characteristics of an optical beam by a perturbation assembly arranged to modify the one or more beam characteristics, the perturbation assembly coupled to the first length of fiber or integral with the first length of fiber, or a combination thereof and a second length of fiber coupled to the first length of fiber and having a second RIP formed to preserve at least a portion of the one or more beam characteristics of the optical beam modified by the perturbation assembly within one or more first confinement regions.

Abstract: Disclosed herein are methods, apparatus, and systems for providing an optical beam delivery system, comprising an optical fiber including a first length of fiber comprising a first RIP formed to enable, at least in part, modification of one or more beam characteristics of an optical beam by a perturbation assembly arranged to modify the one or more beam characteristics, the perturbation assembly coupled to the first length of fiber or integral with the first length of fiber, or a combination thereof and a second length of fiber coupled to the first length of fiber and having a second RIP formed to preserve at least a portion of the one or more beam characteristics of the optical beam modified by the perturbation assembly within one or more first confinement regions.

Abstract: An optical power control system includes a laser source to provide an optical beam, a variable beam characteristics (VBC) fiber, and a controller operatively coupled to the VBC fiber and configured to control, in response to information indicating change in optical power of the optical beam, different states of perturbation so as to control optical power density.

Abstract: An apparatus for heat deposition in additive manufacturing may include: a first optical beam source configured to generate a first optical beam; a second optical beam source configured to generate a second optical beam; and/or an optical system. The optical system may be configured to move the generated first optical beam over a target area. The optical system may be further configured to move the generated second optical beam over the target area so that a path of the second optical beam moving over the target area is dithered about a path of the first optical beam moving over the target area. The optical system may be configured to focus the generated first optical beam at a plane of a target area. The optical system may be further configured to focus the generated second optical beam at the plane of the target area.

Abstract: An optical beam delivery device. The device comprises a first length of fiber comprising a first RIP formed to enable the adjusting of one or more beam characteristics of an optical beam by a perturbation device. The optical beam delivery device further comprises a second length of fiber having a proximal end for receiving the optical beam from the first length of fiber and a distal end. The proximal end is coupled to the first length of fiber. The second length of fiber comprises a second RIP formed to confine at least a portion of the optical beam within one or more confinement regions. A beam modification structure is disposed at, or a distance from, the distal end of the second length of fiber. The beam modification structure is configured to modify at least one property of the optical beam chosen from beam divergence properties, beam spatial properties and beam directional characteristics.

Abstract: An optical beam delivery system, includes: an optical beam source; a fiber assembly situated to receive and modify one or more beam characteristics of an optical beam; and a nonlinear frequency-conversion stage in optical communication with the fiber assembly and situated to receive and frequency-convert an optical beam from a first wavelength to one or more second wavelengths. The fiber assembly includes: a first length of fiber comprising a first RIP formed to enable modification of the one or more beam characteristics of the optical beam by a perturbation device, and a second length of fiber having a second RIP coupled to the first length of fiber, the second RIP formed to confine at least a portion of modified beam characteristics of the optical beam within one or more confinement regions. The first RIP and the second RIP are different.

Abstract: Disclosed are an optical beam delivery device, systems, and methods for sequentially adjusting, with respect to members of a set of confinement regions, a propagation path for establishing a controllable, temporally apparent intensity distribution. The disclosed techniques entail applying to a variable beam characteristics (VBC) fiber different states perturbation to change the propagation path and the members of the set of confinement regions through which a confined portion of an adjusted optical beam propagates, thereby establishing at an output end of the VBC fiber the controllable, temporally apparent intensity distribution.

Abstract: Methods, apparatus, and systems for active saturable absorbance of an optical beam. An active saturable absorber may comprise an optical input to receive an optical beam, and one or more lengths of fiber between the optical input and an optical output. At least one of the lengths of fiber comprises a confinement region that is optically coupled to the output. The active saturable absorber may further comprise an optical detector to sense a characteristic of the optical beam, such as power. The active saturable absorber may further comprise a perturbation device to modulate, through action upon the one or more lengths of fiber, a transmittance of the beam through a fiber confinement region from a lower transmittance level to a higher transmittance level based on an indication of the characteristic sensed while the transmittance level is low.

Abstract: Methods, apparatus, and systems for modulation of a laser beam. An optical modulator may comprise an optical input to receive an optical beam, and one or more lengths of fiber between the optical input and an optical output. At least one of the lengths of fiber comprises a confinement region that is optically coupled to the output. The optical modulator may further comprise a perturbation device to modulate, through action upon the one or more lengths of fiber, a transmittance of the beam through the confinement region from a first transmittance level at a first time instance to a second transmittance level at a second time instance. The optical modulator may further comprise a controller input coupled to the perturbation device, wherein the perturbation device is to act upon the one or more lengths of fiber in response to a control signal received through the controller input.

Abstract: Disclosed herein are methods, apparatus, and systems for a multi-operation optical beam delivery device having a laser source to generate the optical beam. A beam characteristic conditioner that, in response to a control input indicating a change between the different laser process operations, controllably modifies the beam characteristics for a corresponding laser process operation of the different laser process operations. A delivery fiber has an input end coupled to the beam characteristic conditioner and an output end coupled to a process head for performing the corresponding laser process operation.

Abstract: Methods, apparatus, and systems comprising a fiber-coupled laser and time-varying beam characteristics. A laser may generate an optical beam that is launched into one or more lengths of fiber, at least one of which comprises a confinement region that is optically coupled to an output. A perturbation device may modulate, through action upon the one or more lengths of fiber, a beam characteristic over a time period during which the laser is energized. A controller may cause the perturbation device to act upon the one or more lengths of fiber to impart a time-averaged beam characteristic and/or to induce a continuous variation in one or more beam characteristics during system use. A process monitor may sense a metric external to the optical system, and a feedback signal from the process monitor may be coupled into the controller. Dynamic beam characteristics may be modulated based on the feedback signal.

Abstract: A method of making a three-dimensional object. The method comprises: a) positioning a layer of particles over a build plate; b) exposing the layer of particles to a first laser beam having a first set of beam characteristics, thereby heating the layer sufficiently to fuse at least a portion of the particles together to form a build layer; c) exposing a first region of one of i) the layer of particles or ii) the build layer to a second laser beam having a second set of beam characteristics to provide a first temperature profile for the first region; and d) exposing a second region of one of i) the layer of particles or ii) the build layer to a third laser beam having a third set of beam characteristics to provide a second temperature profile for the second region, the second temperature profile being different than the first temperature profile, wherein both the first region and the second region are in the layer of particles or both the first region and the second region are in the build layer.

Abstract: An apparatus for temperature control in additive manufacturing may include: an optical beam source configured to generate one or more optical beams; a homogenizer configured to flatten an irradiance profile of the generated one or more optical beams; and/or an optical system configured to form the generated one or more optical beams so as to match a portion of a shape of a powder bed. The apparatus may include optical beam sources configured to generate two or more optical beams; and/or an optical system configured to form the generated two or more optical beams to match the portion of the shape of the powder bed. The apparatus, using the formed one or more optical beams with the flattened irradiance profile or using the formed two or more optical beams, may be configured to pre-heat the powder bed prior to fusing and/or to post-heat the fused powder bed.

Abstract: Disclosed herein are methods, apparatus, and systems for perturbing a laser beam propagating within a first length of fiber to adjust one or more beam characteristics of the laser beam in the first length of fiber or a second length of fiber or a combination thereof, coupling the perturbed laser beam into a second length of fiber and maintaining at least a portion of one or more adjusted beam characteristics within a second length of fiber having.

Abstract: Additive manufacturing systems and methods for fabricating an article are provided. The additive manufacturing system may include a substrate and a layering device configured to fabricate a first layer of the article on the substrate. The layering device may include an optical beam source configured to generate an optical beam and a variable beam characteristics (VBC) fiber operably coupled with the optical beam source and configured to modify one or more beam characteristics, such as a wavelength, of the optical beam.

Abstract: A method of making a porous three-dimensional object.

Abstract: Disclosed herein are methods, apparatus, and systems for providing an optical beam delivery device, comprising a first length of fiber comprising a first RIP formed to enable modification of one or more beam characteristics of an optical beam by a perturbation device and a second length of fiber having a second RIP coupled to the first length of fiber, the second RIP formed to confine at least a portion of the modified beam characteristics of the optical beam within one or more confinement regions.

Abstract: An optical beam delivery device is configured to generate, from an optical beam, selectable intensity profiles. The device has a first length of fiber having a first refractive index profile (RIP), and a second length of fiber having second RIP that is different from the first RIP. The second length of fiber includes coaxial confinement regions arranged to confine at least a portion of an adjusted optical beam. The confined portion corresponds to an intensity distribution of different intensity distributions. The intensity distribution is established by a corresponding state of different states of perturbation that is applied to the device such that the confined portion is configured to provide, at an output of the second length of fiber, a selected intensity profile of the selectable intensity profiles.

Abstract: Systems and methods for modifying an optical beam and adjusting one or more beam characteristics of an optical beam are provided. The system may include a first length of fiber operably coupled with an optical beam source and configured to receive an optical beam therefrom. The system may also include a perturbation device operably coupled with the first length of fiber and configured to modify the optical beam traversing therethrough, and a second length of fiber operably coupled with the first length of fiber and configured to receive the modified optical beam therefrom. The system may further include a beam shaping assembly configured to receive the modified optical beam from the second length of fiber, adjust one or more beam characteristics of the modified optical beam, and direct the adjusted optical beam to a downstream process.

Abstract: An optical beam delivery device formed of optical fibers that are configured to produce an output exhibiting an intensity distribution profile having non-zero ellipticity includes a first length of fiber through which an incident optical beam having beam characteristics propagates and which has a first refractive index profile (RIP). The first RIP enables, in response to an applied perturbation, modification of the beam characteristics of the optical beam to form an adjusted beam having modified beam characteristics relative to the beam characteristics of the optical beam. A second length of fiber is coupled to the first length of fiber and formed with a set of one or more confinement regions that define a second RIP and confine at least a portion of the adjusted beam to generate, at an output of the second length of fiber, an intensity distribution profile having non-zero ellipticity.