Laser power monitoring in a heat-assisted magnetic recording device using a resistive sensor and high-frequency laser modulation
US10240975B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 23, 2016 |
| Grant date | Mar 26, 2019 |
| Priority date | — |
| Expiry date | Feb 13, 2037 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01K7/16
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus comprises a light source configured to generate light, and a modulator coupled to the light source and configured to modulate the light above a predetermined frequency. A slider is configured for heat-assisted magnetic recording and to receive the modulated light. A resistive sensor is integral to the slider and subject to heating by absorption of electromagnetic radiation and conduction of heat. Measuring circuitry is coupled to the resistive sensor and configured to measure a response of the resistive sensor due to absorbed electromagnetic radiation and not from the heat conduction. The measuring circuitry may further be configured to determine output optical power of the light source using the measured resistive sensor response.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.