On the characteristics of pole-keeper head fields

A definition of the term head-field is suggested and followed for cases where the recording medium has a high permeability layer. It is shown that an exact correspondence exists between the fields of conventional ring heads and pole-keeper heads. Since ring head fields are generally well known it follows that new analyses for pole-keeper heads are not necessarily required. In the cases where the ring head gap and the pole-keeper spacing become very small, it is shown that the fields in the trailing region are identical. Thus the writing processes on any recording layer with a small gap ring head and a small spacing pole-keeper head will be very similar.