Tapered core fiber manufacturing methods

摘要

Tapered core fibers are produced using tapered core rods that can be etched or ground so that a fiber cladding has a constant diameter. The tapered core can be an actively doped core, or a passive core. One or more sleeving tubes can be collapsed onto a tapered core rod and exterior portions of the collapsed sleeving tubes can be ground to provide a constant cladding diameter in a fiber drawn from the preform.

主权项

1. An optical fiber, comprising:
a tapered core that extends along a propagation axis, wherein the tapered core is at least partially doped with a rare earth element; and an inner cladding that surrounds the core and extends along the propagation axis, wherein the tapered core and the inner cladding have respective cross-sectional areas ACORE, AINNER, and a ratio ACORE/AINNER varies along the propagation axis, wherein the tapered core and the inner cladding define a plurality of portions with few mode cores and a plurality of portions that define single mode waveguides, wherein the single mode waveguide portions and the few mode core portions are spatially separate and alternatingly disposed along the propagation axis, and wherein an outer edge of the inner cladding defines a constant cross-sectional area.