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:
Dec. 18, 1990
Filed:
Jul. 13, 1989
Kiyoshi Kimoto, Machida, JP;
Shinichi Tanaka, Kamakura, JP;
Nikon Corporation, Tokyo, JP;
Abstract
An apparatus for recording information on an optical type recording medium alternately generates a binary signal of a first frequency and a binary signal of a second frequency lower than the first frequency, applies radiation to the medium and writes the binary signals of the first frequency and the second frequency into the medium, reproduces the binary signals of the first frequency and the second frequency written into the medium and converts them to electrical signals, AC-amplifies the electrical signals, detects the difference between the amplitude of the output of the AC amplifier of a level higher than a reference level, which corresponds to the first frequency and of a level lower than the reference level, which corresponds to the first frequency and outputs a detection signal, and responds to the detection signal to control the intensity of the radiation applied to the medium for writing.