Deterioration of taper lens performance due to taper asymmetry

The influence of rotationally asymmetrical, i.e. bent drawn, fiber tapers on the coupling performance of taper lenses used for laser diode- or LED-to-single-mode-fiber coupling is investigated. It is found by experiments that the lateral offset of the taper tip with respect to the fiber axis should be below approximately=6 mu m if a significant increase in coupling loss is to be avoided. The experimental results are interpreted by numerical simulations applying the beam propagation method.<
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