The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 13, 2009
Filed:
Nov. 26, 2003
Hubert Cécile François Martens, Eindhoven, NL;
Benno Tieke, Eindhoven, NL;
Hubert Cécile François Martens, Eindhoven, NL;
Benno Tieke, Eindhoven, NL;
Koninklijke Philips Electronics N.V., Eindhoven, NL;
Abstract
A dual-stack recordable optical data storage medium wherein a focused radiation beam having a wavelength λ enters through an entrance face of the medium during recording. The medium includes a substrate, a first recording stack L, including a recording layer, the first recording stack Lhaving an optical reflection value Rand an optical absorption value Aat the wavelength λ, and a second recording stack Lincluding a recording layer, the second recording stack Lhaving an optical reflection value Rand an optical absorption value Aat the wavelength λ, and a transparent spacer layer between the recording stacks. The second stack is closer to the entrance face than the first stack. By fulfilling the formula AR−√(R/R), where Ris the minimum effective optical reflection value for each recording stack, full compatibility is achieved with a read only version of the medium.