Absolute track width measurement on magnetic recording heads
US6642713B2 · kind B2 · utility
8Cited by
5References
8Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Mar 25, 2002 |
| Grant date | Nov 4, 2003 |
| Priority date | — |
| Expiry date | Mar 25, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B33/10
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method for magnetically measuring the magnetic read width (MRW) of magnetic recording heads having a track width that is equal or smaller than the wavelength of visible light is provided. The heads comprise a magnetic read head spin valve sensor and the magnetic read head sensor signal is used to derive an unknown track width from comparing to the sensor response of a known track width. Using this method, track widths in the regions at the wavelength of light and below (<500 nm) can be directly measured without destroying the respective sensor material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.