Algorithm performance in the determination of the refractive-index profile of optical fibers

Three algorithms for computing the refractive-index profile of azimuthally symmetric optical fibers via the inverse Abel transform are compared to determine their relative accuracies. Appropriate values of algorithm parameters are also determined. The direct differentiation algorithm, the iterative algorithm, and the Fourier algorithm are used to calculate the refractive-index profile from simulated measurements of the phase shift of light transmitted transversely through the fiber. The rms error in the calculated index profile is used to quantify the accuracy of each algorithm. The Fourier algorithm is typically the most accurate of the three.