Induction-type magnetic head especially for disk or tape drive

摘要

A magnetic head has a lower magnetic pole (21), an insulating film (23) formed on the lower magnetic pole, a coil located above the lower magnetic pole and extending through the insulating film, and an upper magnetic pole (24) with a pole (24a) at its upper end which forms a gap with the lower magnetic pole (21). The upper magnetic pole (24) consists of a magnetic material which has a saturation magnetic flux density Bs(T) and a resistivity rho (in mu OMICRON .cm) and which is formed on the insulating film (23) as a layer of thickness delta (in mu ), both sides of the upper magnetic pole (24) extending from root sections of the pole (24a) with a cone angle eta (in deg ). The upper magnetic pole (24) satisfies the relationship (1 + tan eta ) delta Bs// rho 2 <= 1.0. Also claimed is a similar magnetic head in which the upper magnetic pole consists of several superposed magnetic layers preferably selected from NiFe, FeN, FeZrN and CoNiFeS.