| 摘要 |
PURPOSE:To prevent the influence of a pseudo gap at the time of reproduction while obtaining a strong recording magnetic field at the time of recording by providing a high magnetic permeability part near the gap of magnetic materials and forming the boundary face thereof non-parallel with the longitudinal direction of the gap and within the track width in the track width direction. CONSTITUTION:The part muh where the magnetic permeability is high is provided to the central part in the track width direction near the gap (g) of pole pieces and the other parts are formed as the part mul where the magnetic permeability is low. The boundary face aa' of the magnetic permeability is so formed as to be non-parallel with the longitudinal direction of the gap. All the magnetic material parts are thereby made into poles at the time of recording but only the part of the high magnetic permeability muh appears and the reproduction track width attains the base of a triangular shape at the time of reproducing. Further, the parts parallel with the longitudinal direction of the gap are eliminated at the boundary face and the influence of the pseudo gap is eliminated. Since the base of the trapezoidal shape is longer than the base of the triangular shape, the crosstalk noises from the adjacent tracks are decreased. |
