Inductive transducer with stitched pole tip and pedestal defining zero throat height
US6721138B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 24, 2001 |
| Grant date | Apr 13, 2004 |
| Priority date | — |
| Expiry date | Jan 8, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2005/3996
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An inductive transducer having first and second magnetic pedestals disposed between first and second magnetic pole layers and adjacent to a media-facing surface, the pedestals separated by a submicron, nonmagnetic gap. The first pedestal extends less than the second pedestal from the media-facing surface, defining a short throat height. The second pedestal extends further to provide sufficient area for stitching to the second pole layer. The stitching and the thickness provided by the pedestals allow plural coil layers to be disposed between the pole layers, and the second pedestal, as well as other features, can be defined by high-resolution photolithography. The two coil layers have lower resistance, lower inductance and allow the pole layers to be shorter, improving performance. All or part of either or both of the pedestals may be formed of high magnetic saturation material, further enhancing performance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.