Tar with write-synchronized laser modulation
US8570842B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 6, 2012 |
| Grant date | Oct 29, 2013 |
| Priority date | — |
| Expiry date | Jun 6, 2032 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2005/0021
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Instead of using discontinuous step functions or pulses to drive a laser of a TAR enabled disk drive between on and off, a fixed modulation frequency may be used that alternates between a high and low laser power such that the radiation source is always delivering heat to the magnetic media when writing data to the magnetic disk. The magnetic field of the write pole may be synchronized to the modulation frequency of the radiation source to ensure that the radiation source heats the magnetic media proximate to the write pole above the grain freezing temperature when the Zeeman energy produced by the magnetic field of the write pole exceeds the thermal energy of the magnetic media.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.