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:
Jan. 16, 1996
Filed:
Dec. 16, 1992
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A method of recording new information on a recording medium on which information was previously recorded is performed as follows. The new information is stored in a memory. The new information is overwritten onto a portion of the recording medium where the old information was recorded by scanning the recording medium with a light beam. A signal including both the old information and the new information is reproduced from the light beam reflected by the recording medium simultaneously with the overwriting. A signal component corresponding to the new information is extracted from the reproduced signal. The extracted signal component is compared with the new information stored in the memory. It is determined on the basis of a comparison result whether or not the recording has been correctly performed.