Miniaturized low-power-consumption optical head provided with a state transformation mechanism
US5150343A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 19, 1990 |
| Grant date | Sep 22, 1992 |
| Priority date | — |
| Expiry date | Jul 19, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/08517
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical head which includes a movable bobbin having an objective lens and tracking coils for tracking operation, a carriage guided in such a manner to be able to move in the tracking direction and a state transformation mechanism for transforming the state of the bobbin and carriage between a first state, in which the objective lens can move in the tracking direction but the carriage does not move in the tracking direction, and a second state, in which the movable bobbin and the carriage moves in the tracking direction as one body. When effecting a tracking operation, the state transformation mechanism transforms the state of the bobbin and the carriage into the first state, in which the objective lens can move in the tracking direction but the carriage does not move in the tracking direction, and a tracking drive current is then made to flow through the tracking coils to perform the tracking operation. This results in that the objective lens is supported by a system of a single degree of freedom, of which characteristics are determined by the mass of the movable bobbin and the spring constant of the bobbin supporting means. In contrast, when effecting an access operation, the s…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.