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:
May. 23, 1989
Filed:
Apr. 21, 1986
Yoshiro Yoda, Tokyo, JP;
Olympus Optical Co., Ltd., Tokyo, JP;
Abstract
A reproduction apparatus for an optical magnetic disk having data recorded in a magneto-optical recording form and an address recorded in an optical recording form, includes a pickup for detecting P- and S-axis components of a linearly polarized laser beam reflected on an optical magnetic disk, an adder for adding the P- and S-axis components, and a subtracter for subtracting the S-axis component from the P-axis component. A reproduction signal processing circuit confines an output of the adder and that of the subtracter to produce a reproduction signal. A comparator converts the reproduction signal into a binary signal, the reproduction signal processing circuit including a circuit for identifying whether a reproduction signal is one of magneto-optical recording information or one of optical recording information. A variable gain amplifier amplifies the subtraction signal of the P- and S-axis components, at an amplification factor corresponding to a result of identification, in which the reproduction signal of optical recording information has a greater amplification factor than the amplification factor of the reproduction signal for magneto-optical recording information.