Patent · US Expired

System and method for simultaneously verifying optical data writing and optical data writing medium for use therein

US5798993A · kind A · utility

4Cited by
4References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 22, 1996
Grant dateAug 25, 1998
Priority date
Expiry dateMay 22, 2016

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S430/146
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

The optical disk writing system disclosed is one in which data written on an optical data writing medium is verified essentially simultaneously with writing on the medium. The written data is verified by detecting a timing of the light irradiated on the medium and by measuring return light doses at rise and fall of the light irradiated on the medium and comparing the doses thereof with predetermined reference values. The medium uses a phase transition reversible between a crystal state and an amorphous state for writing/reading/erasing of data on a data writing film, and includes a first protective film, a phase transition type data writing film, a second protective film, and a reflection film, formed in this order, on a transparent substrate. The thickness of the first protective film is set such that, of three reflectivities of the data writing film respectively in crystal, amorphous and melted states, the reflectivity in the crystal state and the reflectivity in the melted state are made different from each other, and the reflectivity in the amorphous state and the reflectivity in the melted state are made different from each other. A high speed writing operation can be carried …

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