Abstract: Disclosed is an optical fiber-based divergence-limiting device for limiting divergence from a first maximum divergence of input light to a second maximum divergence of output light, in which the second maximum divergence is less than the first maximum divergence.

Abstract: Disclosed are embodiments for multi-band pumping of a doped fiber source. The doped fiber source has a first absorption band and a second absorption band that is different from the first absorption band. In some embodiments, a first laser pump generates a first pump power in a first pump band corresponding to the first absorption band that is generated. A second laser pump generates a second pump power in a second pump band corresponding to the second absorption band. The second pump band is different from the first pump band. The first and second pump power is simultaneously applied to the doped fiber source.

Abstract: In an example, the disclosed technology includes a laser source, comprising a plurality of pump elements configured to generate laser light, a controller coupled to the plurality of pump elements, configured to select individual drive current levels to be provided to respective ones of the plurality of pump elements responsive to a request for a laser power level and at least one power supply coupled to one or more of the plurality of pump elements for driving individual pump elements at selected drive currents.

Abstract: Signal combined optical fiber devices, systems, and methods for reducing signal spectrum pumping of Raman spectrum. Power of a Raman component in an output of a signal combined fiber laser system may be reduced by diversifying peak signal wavelengths across a plurality of signal generation and/or amplification modules that are input into a signal combiner. In some examples, fiber laser oscillators that are to have their output signals combined to reach a desired cumulative system output power are tuned to output signal bands of sufficiently different wavelengths that signal from separate ones of the oscillators do not collectively pump a single Raman band. With the combined signal component comprising different peak signal wavelengths, the Raman component of combined output may have multiple peak wavelengths and significantly lower power than in systems where signals of substantially the same signal peak wavelength are combined.

Abstract: Optical fiber devices, systems, and methods for separating Raman spectrum from signal spectrum. Once separated, the Raman spectrum may be suppressed (e.g., as a result of a reduction in gain from the signal spectrum, and/or through dissipation of the Raman spectrum energy), while the signal spectrum may be propagated in one or more guided modes of a fiber system. In some embodiments, a fiber system may include a chirped fiber Bragg grating (CFBG) or a long period fiber grating (LPFG), each configured to couple a core propagation mode into a cladding propagation mode with an efficiency that is higher for Raman spectrum than for signal spectrum. A fiber system further may include a cladding light stripper (CLS) configured to preferentially remove cladding modes containing the Raman component.

Abstract: Fiber laser devices, systems, and methods for reducing Raman spectrum in emissions from a resonant cavity. A fiber laser oscillator that is to generate an optical beam may include a Raman reflecting output coupler that strongly reflects a Raman component pumped within the resonant cavity, and partially reflects a signal component to sustain the oscillator and emit a signal that has a reduced Raman component. A Raman filtering output coupler may comprise a superstructure fiber grating, and such a grating may be chirped or otherwise designed to have a desired bandwidth.

Abstract: Optical fiber devices, systems, and methods for coupling Raman spectrum out of an optical fiber selectively over a signal spectrum, which may be propagated in one or more guided modes of a fiber system. A fiber system may include a chirped fiber Bragg grating (CFBG) or a long period fiber grating (LPFG), each to unguide Raman light propagating in a core propagation mode of a fiber completely out of the fiber (through any surrounding cladding layer(s)) selectively over signal spectrum which is to remain in a guided mode of the fiber.

Abstract: Optical fiber devices, systems, and methods for separating Raman spectrum from signal spectrum Raman spectrum may be suppressed as a result of a reduction in gain and/or through dissipation while the signal spectrum may Raman Components In be propagated in one or more guided modes of a fiber system. A fiber system may Length include a propagation mode coupler to couple a first guided mode into a second guided mode with an efficiency that varies as a function of wavelength of the propagated light. Mode coupling efficiency may be higher for Raman spectrum, and lower for signal spectrum so that Raman spectrum associated with a fundamental mode is preferentially coupled into a higher-order mode. A fiber system may include a mode filter operable to discriminate between first and second guided modes. Within the filter, guiding of the first mode may be superior to that of the second mode with Raman spectrum preferentially rejected.

Abstract: An integrating volume for laser light homogenization includes a housing having an interior surface defining a light integrating cavity of a non-spherical configuration in the housing interior, an input port on the housing to allow entry of light from a laser beam through the input port into the light integrating cavity, and an output port on the housing and offset from the input port to allow sampling of light from the light integrating cavity through the output port after the light has reflected in the light integrating cavity between different portions of the interior surface of the housing so as to homogenize the light for sampling at the output port.