Patent · US Expired

Method of and device for recording information on a record carrier having a recording layer which, when heated, undergoes an optically detectable change

US5321682A · kind A · utility

3Cited by
3References
27Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 9, 1992
Grant dateJun 14, 1994
Priority date
Expiry dateNov 9, 2012

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B11/10595
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

Method of and device for recording information on a record carrier having a recording layer by scanning the recording layer with a radiation beam whose power has a pulsatory variation, including radiation pulses of high power, each having decreasing power, relative to and alternating with radiation intervals of low power, each having increasing power. As a result of the heat produced by the radiation pulses, the recording layer undergoes an optically detectable change. A write signal generating circuit converts an information signal into a write signal having a pulsatory pattern, including pulses of high signal values relative to and alternating with intervals of low signal values. A control circuit sets the power of the radiation beam to values fixed by the signal values of the write signal. The signal values of each of the pulses of the write signal decrease and the signal values of each of the intervals of the write signal increase. As a result, the power of the radiation beam decreases during the radiation pulses and increases during the radiation intervals, and the influence exerted by previous radiation pulses on the temperature at the scanning area is taken into account.

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