Mode dispersion for optical fibres of arbitrary cross-section

The recent theory of Snyder and Zheng derived for high-V fibres of arbitrary cross-section is shown to be surprisingly accurate, e.g. it is less than 5% in error for single-mode fibres at cutoff of the second mode. On the basis of their asymptotic expressions, together with our new numerical data, we derive simple empirical formulas with much higher accuracy than previously reported.