Internal mirror optical fiber couplers

A description is given of a way of making mirrored fiber couplers, and test results on both multimode and single-mode taps are reported. The couplers were produced by a fusion splicing process similar to that used for making mirrors oriented normal to the axis in multimode and single-mode fibers. These mirrored fibers serve as compact directional couplers with low excess optical loss ( approximately=0.2 dB for multimode and 0.5 dB for single mode at 1.3 mu m) and excellent mechanical properties. The reflectance is found to be wavelength dependent and strongly polarization dependent, as expected.<
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