Calibration and adjusting target pre-write clearance offset for a heat-assisted magnetic recording device
US9990950B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 17, 2017 |
| Grant date | Jun 5, 2018 |
| Priority date | — |
| Expiry date | Jul 17, 2037 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2005/0021
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An apparatus comprises a slider configured for heat-assisted magnetic coupled to a controller. The slider comprises a writer, a heater, a near-field transducer, and an optical waveguide for communicating light from a laser diode to the near-field transducer. The controller is configured to set a target pre-write clearance of the slider prior to performing a write operation, set a target write clearance of the slider for performing the write operation, and determine a difference between the target pre-write and write clearances to define a target pre-write clearance offset. The controller is also configured to measure, for a plurality of different target pre-write clearance offsets, a writability metric for the slider while sweeping a laser diode current, and adjust the target pre-write clearance offset so that the writability metric reaches a predetermined threshold. The controller is further configured to perform subsequent write operations using the adjusted target pre-write clearance offset.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.