Optical videodisc read unit with tracking and focussing wobblers
US4193091A · kind A · utility
33Cited by
4References
9Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 15, 1978 |
| Grant date | Mar 11, 1980 |
| Priority date | — |
| Expiry date | May 15, 1998 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S5/024
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical read unit for reading radiation-reflecting video discs comprises a semiconductor laser which with the aid of a scan wobbler and a focussing wobbler is moved at high frequency in two directions relative to the video disc, a radial direction for tracking purposes and a direction normal to the disc for the purpose of automatic focussing. The semiconductor diode laser is mounted on a metal radiation source carrier which is connected to a heat sink for carrying off the heat with a low temperature gradient, and is driven by piezo-electric plates.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.