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:
Jun. 08, 2010
Filed:
Jan. 16, 2004
Tsutomu Ishimoto, Saitama, JP;
Tsutomu Ishimoto, Saitama, JP;
Sony Corporation, Tokyo, JP;
Abstract
An information recording and/or reproducing apparatus using a removable disk-shaped optical recording medium () is provided which includes a storage unit () to store an axial-runout amount in a predetermined radial position on the disk-shaped optical recording medium () being rotated, a near-field light projector () provided to condense a light beam emitted from a light source () and which projects the condensed light beam as near-field light when located in a field near the information recording surface of the disk-shaped optical recording medium (), a first controller () which multiplies an axial-runout amount read from the storage unit () by a predetermined gain to generate a control signal and controls the near-field light projector () to follow the axial-runout amount of the disk-shaped optical recording medium (), and a second controller () to control the near-field light projector () on the basis of the linear characteristic of the return-light amount of the near-field light to keep a predetermined distance in the near field from the information recording surface.