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:
Jul. 04, 2006
Filed:
Sep. 17, 2002
Takashi Masaki, Kawasaki, JP;
Toru Ikeda, Kawasaki, JP;
Takashi Masaki, Kawasaki, JP;
Toru Ikeda, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
The present invention provides a low-cost optical recording device that determines an optimum quantity of light for recording and reproducing, and an optimum focus offset value. The present invention also relates to a method of determining such an optimum focus offset value. The optical recording device is equipped with a focus control system for performing a focus control operation to focus light from a light source onto a recording face of an optical recording medium. This optical recording device includes: a focus offset value setting unit for sequentially setting a plurality of offset values for the focus control system; an adder unit for using each focus offset value to adjust the focus control system; a light quantity setting unit for sequentially setting a quantity of recording light emitted from the light source at a plurality of predetermined values; a recording unit for recording information on the optical recording medium; an error rate measuring unit for measuring an error rate in the information reproduced from the optical recording medium; and an optimum focus offset value determining unit for determining an optimum focus offset value based on the measured error rate.