Fine access method and circuit for an optical disk drive using a multi-track jump
US4899325A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 5, 1988 |
| Grant date | Feb 6, 1990 |
| Priority date | — |
| Expiry date | May 5, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/08529
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A fine access method for an optical disk drive uses a multi-track jump method to cover a wide range of several hundred tracks at a high speed. According to the present invention, one-shot acceleration and deceleration pulses with a short width are sent to an actuator head immediately after every one-half track pitch travel of the actuator head. The actuator head is accelerated when the travel time for one-half track pitch is slower than a first reference time and it is decelerated when the travel time is faster than a second reference time. When the travel time is between the first and second reference times, no pulse is sent to the actuator head. Thus the velocity of the actuator head is compensated and maintained within a specified range of deviation for a whole long range of jumping a plurality of tracks.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.