Optical scanning arrangement for maintaining constant the light output of a laser beam or the laser current
US5016233A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 28, 1988 |
| Grant date | May 14, 1991 |
| Priority date | — |
| Expiry date | Sep 28, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/0908
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical scanning arrangement in which a laser beam is generated by a source with a monitor diode. The laser beam is focused on an optical recording medium. A summing amplifier has a first input connected to a source of a periodic signal. This source of periodic signal is also connected to a first input of a multiplier. The multiplier has an output connected to a second input of the summing amplifier. This summing amplifier has an output connected to a positioning device in the focusing circuit for the laser beam. This focusing circuit has an actual value which is supplied to a third input of the summing amplifier. The multiplier receives a laser controlling signal on a second input for the purpose of maintaining the light output of the laser beam at a constant level.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.