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:
Aug. 09, 2011
Filed:
May. 23, 2005
Yoshimi Iso, Tokyo, JP;
Mitsuo Hagiwara, Tokyo, JP;
Mitsuyuki Kimura, Tokyo, JP;
Renesas Electronics Corporation, Kanagawa, JP;
Abstract
The optical disc device has a circuitwhich forms a focus error signal FER for focus servo control based on reflection light from an optical disc exposed to laser light. A data processing unitcan control by feedback a position to which an objective lens is moved by a focusing actuatorbased on the focus error signal. In label printing, the data processing unit controls, by feedforward, a position to which the objective lens is moved by the focusing actuator based on control data for label printing. The operation resolution of the focusing actuator in feedforward control is made higher than that in feedback control. Thus, an intended position control accuracy is achieved in feedforward control. For instance, in feedforward control, the gain of the driver circuitfor the focusing actuator is switched to a smaller one in comparison to that in feedback control.