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:
Apr. 22, 2008
Filed:
Jul. 23, 2003
Yuji Tawaragi, Tokorozawa, JP;
Yuji Tawaragi, Tokorozawa, JP;
Pioneer Corporation, Tokyo, JP;
Abstract
A push-pull signal Spp fetched with tracking open is smoothed to a smoothing signal Spp to remove signal components generated wobbling due to radial runout, and the smoothing signal is binarized to compute an autocorrelation value in the autocorrelation computing circuit. This computing is made by multiplying the binarized signal by a signal delayed by the half cycle and sign-negated to compute the integrated value, and the integrated value output signal Dint is generated. A maximum value of the integrated value output signal Dint within a predetermined period of time is computed by the maximum value holding circuitto output a maximum value output signal Dout. Depending on the amplitude of the maximum value signal Dout, the CPUdetermines whether the recording medium is a writable one or read only one. Wobble determination can be made keeping tracking open, and a type of a recording medium is carried out accurately.