Splice Loss in Dispersion-Modified Single-Mode Silica Fibers: Effect of Non-Gaussian Fields

We examine the nature of non-Gaussian fields in dispersion- modified single-mode silica fibers. In particular, we show the limitations of using two well-known Gaussian approximations for the theoretical prediction of splice loss caused by lateral and angular misalignments. Exact numerical calculations of splice loss with small lateral and angular offsets are compared to approximations obtained by using 1) the Petermann 2 mode-field radius and 2) the mode-field radius which maximizes the coupling efficiency for Gaussian beam excitation. The accuracy of each is discussed. © 1989 IEE