Disk drive calibrating laser power and write current for heat assisted magnetic recording
US8854929B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 6, 2013 |
| Grant date | Oct 7, 2014 |
| Priority date | — |
| Expiry date | Mar 6, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2005/0021
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A disk drive is disclosed comprising a head actuated over a disk, wherein the head comprises a laser operable to heat the disk while writing data to the disk. An initial laser power of the laser is configured. After a time interval, an operating laser power of the laser is measured, and when the operating laser power falls below the initial laser power, a control signal applied to the laser is first adjusted until the operating laser power substantially matches the initial laser power. After first adjusting the control signal applied to the laser, a quality metric representing a recording quality of the head is measured, and when the quality metric indicates a poor recording quality, the control signal applied to the laser is second adjusted so that the operating laser power exceeds the initial laser power.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.