摘要 |
A single-mode fiber of increased core size consists of a "few-mode" fiber, of core size sufficient for guiding up to three high-order modes in addition to the fundamental mode, by interposing perturbations of such spacing along the fiber, as to selectively couple any such high-order modes to (unguided) cladding modes, thereby rejecting all but the fundamental mode. Unwanted coupling of the fundamental mode, leading to added fiber loss, is minimized by appropriate refractive index profile design.
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