Waveform shaping method and apparatus for optical recording
US5297129A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 24, 1992 |
| Grant date | Mar 22, 1994 |
| Priority date | — |
| Expiry date | Dec 24, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/0045
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Method and apparatus for improving the characteristics of the surface effects recorded on an optical disc, for use with an optical recording apparatus which includes a writing light beam source and an optical modulator for modulating the intensity of the writing beam of light above and below a threshold level of a moving recording medium in response to a modulator drive signal for recording information on the medium, the light beam being capable of forming a track of surface effects or indicia in the moving recording medium when the writing beam is above threshold and incapable of forming surface effects in the moving recording medium when the writing beam is below threshold. The method includes receiving a substantially rectangular waveform having leading and trailing edges, provided as a modulator drive signal to modulate the writing beam to a peak power above threshold and to a minimum power level below thresholds, respectively, and producing a shaped modulator drive signal by increasing the peak power of the writing beam responsive to the occurrence of the leading edges, by decreasing the time the shaped modulator drive signal is above threshold in order to maintain a prescribe…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.