Method and apparatus for calibrating a glide head and detection system for a magnetic disk drive
US6142006A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 24, 1998 |
| Grant date | Nov 7, 2000 |
| Priority date | — |
| Expiry date | Jul 24, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2291/014
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus for calibrating a glide head and detector system performs a pre-screening to ensure the quality of the glide head and the piezoelectric sensor in the detection system. The glide head and the piezoelectric sensor detect a signal when the glide head makes contact with the disk, such as a magnetic recording disk. Calibration of the detection system utilizes a specially made bump disk that has asperities of desired height and size that protrude out of a flat disk surface. The glide head is flown over the bump disk, and by gradually reducing the disk spinning velocity, the head is brought closer to the disk and eventually into contact with the asperity. The onset of contact, as detected by the piezoelectric sensor, defines a disk spinning velocity for the head to fly at the desired height. In order to decouple the glide head flying characteristics and the piezoelectric quality and transfer function from other factors that affect the calibration of the detection system, laser pulses are directed at the glide head. Head vibrations are introduced in the glide head and detected by the piezoelectric sensor. The head excitations are recorded as a spectrogram in which th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.