| 摘要 |
<p>A thin film magnetic head provided with an upper sub-magnetic pole (40) facing a medium opposing surface at the front end thereof and extending in a longitudinal direction and with a specified thickness along a reference surface (41). An intermediate magnetic pole layer which extends along the reference surface and is defined to be larger in a track width direction than the upper sub-magnetic pole is connected to the rear end of the upper sub-magnetic pole. An upper magnetic pole layer (33) supported on the front surface of the intermediate magnetic pole layer projects at the tip end thereof facing the medium opposing surface from the pole (40) by a specified distance ΔPW in the track width direction. For example, when the core width CW of the pole (40) is set to at least 0.7 νm, the thickness SL of the pole (40) is set to at least 2.5 times the projecting distance ΔPW of the upper magnetic pole layer (33). Setting the thickness SL of pole (40) ensures a sufficient magnetic field intensity (e.g., at least 470 kA/m) for an information record between the pole (40) and a lower sub-magnetic pole (38), whereas, a magnetic field intensity at the edge of the upper magnetic pole layer (33) projecting in the track width direction is suppressed to below a threshold value (e.g., 135 kA/m) at which recording bleeding and magnetization inversion may be encountered.</p> |
