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:
Sep. 27, 1988
Filed:
Mar. 12, 1987
Hendricus F Van Tongeren, Eindhoven, NL;
Martin A Farla, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
A method and apparatus are described for recording a binary information signal on a record carrier having an information layer whose optical properties are modified upon heating. An information pattern corresponding to the information signal is obtained by moving the record carrier relative to an optical system which focuses a radiation beam onto the information layer. A recording mark is written on the information layer is selected time intervals by locally heating the information layer with the focussed radiation beam. The amount of radiation energy applied during a selected time interval depends on the position of the selected time interval in the sequence of consecutive selected time intervals. This provides compensation for the increase in the temperature at the location where the mark is to be recorded due to heating of the layer during recording of a mark in the preceding time interval. The amount of radiant energy that is applied is chosen so that for each recording mark the temperature which is reached in the information layer, and hence the size of the recording mark, is substantially the same.