The transverse permeability ratio (TPR) and longitudinal permeability ratio
(LPR) as a function of an external field of mumetal films have been invest
igated in conjunction with the magnetic properties. The mumetal films were
prepared by the R.F.magnetron sputtering method in Ar atmosphere. The LPR c
urve shows the single peak pattern, and the TPR curve shows the double peak
pattern indicating the existence of the magnetic anisotropy effect. The ma
gnitude of the incremental permeability are strongly depended on the magnet
ic softness. The large changes of LPR and TPR in low external fields can be
useful for the evaluation of the magnetic softness.