Analytic solution of cut-off wavelength of bend-insensitive fibers based on frustrated total reflection

摘要

An analytic method for solving the cut-off wavelength of single groove-assisted bend-insensitive fiber (BIF) was proposed. Combined with the concepts of frustrated total reflection and numerical aperture, the cut-off wavelength formula for the BIF was deduced. Experimental results showed that, compared to the traditional analytic and numeric methods, this method had higher accuracy in the calculation of cutoff wavelength for BIFs that had a large proportion of depressed inner-cladding layer, which significantly expanded the range of accurately predicting the cut-off wavelength.