Jitter in a Voronoi Pattern Media-Effect of Grain Size Distribution and Reader Width

We calculate jitter of the signal from transitions written on Voronoi-pattern media and played back with readers of varying widths. The expected dependence of jitter on reader width, as predicted by the microtrack model, is verified down to very narrow readers. Decrease in grain size variance results in less jitter. The original Voronoi patterns give a jitter value very close to the microtrack model. However, when the Voronoi patterns are modified such that grain size distribution is reduced, the jitter can be significantly smaller than in the microtrack model. This is due to the reduced randomness in the distribution of grain centers.