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. 01, 2001
Filed:
Oct. 29, 1998
Akihito Nakayama, Singapore, SG;
Kenji Shintani, Singapore, SG;
Shunsuke Kohama, Chiba, JP;
Yukari Hashimoto, Yokohama, JP;
Hideo Kato, Kanagawa, JP;
Other;
Abstract
A device for measuring characteristics of an optical pickup and/or an optical disc by which characteristics of tracking signals can be measured accurately in a noise-free manner. The measurement device,has a sample-and-hold circuit,and an analog-to-digital converter,for directly sampling an output of an optical pickup,as signals A to F in order to store the resulting digital data in a second memory,. An arithmetic-logic unit,measures tracking error signals based on the digital data stored in the second memory,. The arithmetic-logic unit,eliminates unstable portions of the tracking signals generated responsive to rotational eccentricity of the optical disc to find data.