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. 05, 2009
Filed:
May. 12, 2004
Koji Tomioka, Sagamihara, JP;
Koji Tomioka, Sagamihara, JP;
Asahi Kasei Microsystems Co., Ltd., Tokyo, JP;
Abstract
A mark S/H circuit () samples, for example, a signal A generated as a photodetector () detects a return beam from marks of an optical disk (), a space S/H circuit () samples a signal A generated through detection of a return beam from spaces, and amplifiers (and) justify amplitudes of the sampled A signals from the marks and spaces. A mark/space selector switch () selects alternately and combines the mark and space signals whose amplitudes have been justified. After A, B, C, and D signals Ato Dare subjected individually to a series of processes up to the combination process, a wobble processing circuit () adds them in predetermined combinations, finds differences among the added signals after justifying the amplitudes of the added signals, and thereby reproduces a wobble signal ().