Dividing marks in optical media to decrease adjacent track crosstalk
US5974022A · kind A · utility
2Cited by
0References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 21, 1997 |
| Grant date | Oct 26, 1999 |
| Priority date | — |
| Expiry date | Jul 21, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/00718
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The present invention includes a method and apparatus for reducing the signal amplitude in long marks which are written into optical disks. When forming a long mark, an increased signal amplitude is typically caused by the blooming toward the end of the mark, and is often sensed by the focused spot in the adjacent track causing increased adjacent track crosstalk (ATC). However, when forming short marks, the effect of blooming is minimized. Therefore, by splitting a long mark into a sequence of short period marks, with short period spaces (1T) between each short period mark, the effect of blooming is substantially reduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.