Patent · US Expired

Detection of saved sectors on an optical disk

US5297115A · kind A · utility

10Cited by
2References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 30, 1992
Grant dateMar 22, 1994
Priority date
Expiry dateJul 30, 2012

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B19/04
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

In an optical disk drive system, an apparatus and method for determining whether data read from a particular field within a particular sector of an optical disk corresponds to a code which specifies that the sector should not be erased. A crystal clock generates a synthesized clock signal. A front-end detector generates a signal synchronized to the synthesized clock signal which represents data read from the field. The signal is then serially shifted by a serial shift register. A comparator compares the shifted signal with the code specifying that the sector should not be erased. If there is a match, a counter is incremented. When the counter reaches or exceeds a pre-determined number, a signal is sent to the optical disk drive system indicating that the sector contains data which should not be erased.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.