Experimental Verification of Microbending Theory Using Mode Coupling to Discrete Cladding Modes
نویسندگان
چکیده
In this paper the existence of discrete cladding modes in single mode fibers is illustrated. This is done by inducing periodically repeated microbends along the fiber axis, whereupon spectral measurements of the additional loss are performed. In order to explain the results of these measurements, it is necessary to apply a microbending theory in which coupling between the guided mode and a number of discrete cladding modes is considered. Very good agreement between theory and measurements is achieved. We will finally discuss the consequences of the existence of discrete cladding modes on the proper choice of artificial microbending spectrum used for fiber character-
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