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:
Nov. 02, 1976
Filed:
Nov. 25, 1974
Hansjoachim Hamisch, Berlin, DT;
Hans-Jurgen Kaiser, Berlin, DT;
Robert Bosch G.m.b.H., Stuttgart, DT;
Abstract
An article for the recording and storage of information includes a support and a layer for storing information provided on the support. The layer is amorphous and composed of a mixture which includes an element of the group bismuth, antimony and selenium and a different element of the group selenium and tellurium. Information may be recorded on the layer by burning away selected regions thereof with high-energy radiation such as a laser beam. A preferred mixture includes bismuth and selenium with the weight ratio of bismuth to selenium being between about 1:2.5 and 1:3.5 for radiation having a wavelength corresponding to visible blue light and with the proportion of selenium being increased for longer wavelengths such as those corresponding to visible green and red light. The layer has a thickness which corresponds to a fraction of the wavelength of the radiation used for recording and the layer is optically opaque. A coating of lacquer may be applied over the layer prior to and/or subsequent to the recording operation so as to protect the layer. The layer is advantageously formed by vapor-depositing the elements selected from the above-mentioned groups onto the support simultaneously.