Abstract: Spectral beam combining systems including a multi-element transform optic. In certain examples the multi-element transform optic includes a first cylindrical optical element having positive optical power in a first axis, a second optical element having negative optical power in the first axis, and a third toroidal optical element having positive optical power in the first axis and either positive or negative optical power in a second axis that is orthogonal to the first axis. The first and third optical elements are positioned on opposite sides of the second optical element and equidistant from the second optical element. The multi-element transform optic has an optical path length extending between a front focal plane and a back focal plane that is shorter than an effective focal length of the multi-element transform optic.

Abstract: The present disclosure relates to systems and methods for reducing thermal effects in double-clad clad optical fiber amplifying systems via control of the pump absorption. One optical fiber amplifying system for reducing thermal effects includes one or more first optical pump sources, each configured to output radiation of a pump wavelength, a bridge optical fiber, having an input configured to receive the radiation of the pump wavelength output by the one or more first optical pump sources and an output, and an active optical fiber that has a first end substantially directly coupled to the output of the bridge optical fiber and a second end. The active optical fiber is configured to amplify radiation of the first active wavelength when pumped with radiation of the pump wavelength.

Abstract: Spectral beam combining systems including a multi-element transform optic. In certain examples the multi-element transform optic includes a first cylindrical optical element having positive optical power in a first axis, a second optical element having negative optical power in the first axis, and a third toroidal optical element having positive optical power in the first axis and either positive or negative optical power in a second axis that is orthogonal to the first axis. The first and third optical elements are positioned on opposite sides of the second optical element and equidistant from the second optical element. The multi-element transform optic has an optical path length extending between a front focal plane and a back focal plane that is shorter than an effective focal length of the multi-element transform optic.

Abstract: The present disclosure relates to systems and methods for reducing thermal effects in double-clad clad optical fiber amplifying systems via control of the pump absorption. One optical fiber amplifying system for reducing thermal effects includes one or more first optical pump sources, each configured to output radiation of a pump wavelength, a bridge optical fiber, having an input configured to receive the radiation of the pump wavelength output by the one or more first optical pump sources and an output, and an active optical fiber that has a first end substantially directly coupled to the output of the bridge optical fiber and a second end. The active optical fiber is configured to amplify radiation of the first active wavelength when pumped with radiation of the pump wavelength.

Abstract: Single mode fiber beam combiners are formed by extending single mode fibers through a glass ferrule, and tapering and fusing the fibers and the ferrule. Tapers can be selected so that optical power input to each of the single mode fibers remains partially guided by the single mode fiber cladding, or is guided by the multimode fiber formed by the glass ferrule and the fused fiber claddings. Such combiners can include double clad fibers or actively doped fibers for use in lasers or amplifiers.