The invention relates to a supercontinuum light source comprising a microstructured optical fiber and a pump light source. The microstructured optical fiber comprises a core and a cladding region surrounding the core, as well as a first fiber length section, a second fiber length section and an intermediate fiber length section between said first and second fiber length sections. The first fiber length section comprises a core with a first characteristic core diameter. The second fiber length section comprises a core with a second characteristic core diameter, smaller than said first characteristic core diameter, where said second characteristic core diameter is substantially constant along said second fiber length section. The intermediate length section of the optical fiber comprises a core which is tapered from said first characteristic core diameter to said second characteristic core diameter over a tapered length.

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.

A combined OCT/pressure sensor system includes an optical cable comprising a single-mode core and a multi-mode core. An OCT optical imaging sensor near a distal end of the optical cable can be inserted into a lumen of a living being. First light exiting a distal end of the single-mode core illuminates an interior of the lumen. The OCT optical imaging sensor acquires image information about the interior of the lumen and transmits an optical signal carrying the image information into the distal end of the single-mode core, toward a proximal end of the single-mode core. An optical pressure sensor attached near the OCT optical imaging sensor receives second light from the distal end of the optical cable, senses ambient pressure within the lumen and transmits an optical signal indicative of the ambient pressure into a distal end of the multi-mode core, toward a proximal end of the multi-mode core.

In various embodiments, the beam parameter product and/or beam shape of a laser beam is adjusted by coupling the laser beam into an optical fiber of a fiber bundle and directing the laser beam onto one or more in-coupling locations on the input end of the optical fiber. The beam emitted at the output end of the optical fiber may be utilized to process a workpiece.

A method of materials processing using an optical beam includes: 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; modifying 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; 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 can be the same as or differ from the second RIP. The modifying of the one or more beam characteristics can include changing the one or more beam characteristics from a first state to a second state. The first state can differ from the second state.

Fiber bending mechanisms vary beam characteristics by deflecting or bending one or more fibers, by urging portions of one or more fibers toward a fiber shaping surface having a selectable curvature, or by selecting a fiber length that is to be urged toward the fiber shaping surface. In some examples, a fiber is secured to a flexible plate to conform to a variable curvature of the flexible plate. In other examples, a variable length of a fiber is pulled or pushed toward a fiber shaping surface, and the length of the fiber or a curvature of the flexible plate provide modification of fiber beam characteristics.

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. The optical beam delivery system may include an optical system coupled to the second length of fiber including one or more free-space optics configured to receive and transmit an optical beam comprising the modified one or more beam characteristics.

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. The optical beam delivery system may include an optical system coupled to the second length of fiber including one or more free-space optics configured to receive and transmit an optical beam comprising the modified one or more beam characteristics.

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.

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.