Method to measure thermal protrusion by sensing spacing change due to pre-lasing
US11587587B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 23, 2022 |
| Grant date | Feb 21, 2023 |
| Priority date | — |
| Expiry date | Feb 23, 2042 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2005/0021
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Various illustrative aspects are directed to a data storage device, comprising: one or more disks; an actuator assembly comprising a head, and configured to position the head over a corresponding disk surface; and one or more processing devices, the head comprising: a write element; a laser unit; and a fly height control element, and wherein the one or more processing devices are configured to: iteratively perform spiral write operations of spiral patterns comprising a plurality of sync marks with the head on the corresponding disk surface, wherein the spiral write operations are performed at: a plurality of values of laser pre-bias current, write backoff, and/or start disk phase; detect pattern signal amplitudes of the spiral patterns on the corresponding disk surface; and determine a relation of write backoff to laser pre-bias current for the head, based on the pattern signal amplitudes of the spiral patterns.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.