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:
Nov. 08, 2011
Filed:
Aug. 23, 2010
Stephan Knappmann, Zimmern ob Rottweil, DE;
Joachim Knittel, Tuttlingen, DE;
Juergen Moessner, Brigachtal, DE;
Stephan Knappmann, Zimmern ob Rottweil, DE;
Joachim Knittel, Tuttlingen, DE;
Juergen Moessner, Brigachtal, DE;
Thomson Licensing, Issy les Moulineaux, FR;
Abstract
Optical pickupfor operation in the far-field and in the near-field mode comprising a movable parthaving an objective lenscomprising a solid immersion lensand a multifocal lens, which are both disposed on a common optical axis A. The multifocal lenscomprises a central zoneand a peripheral zonebeing circumferential to the central zone. The peripheral zone is adapted to constitute an optical system for a far-field mode. The central zoneof the multifocal lenstogether with the solid immersion lensare adapted to constitute an optical system for a near-field mode. The solid immersion lens and the multifocal lens are adapted to be moved in unison. A method for operating an optical pickupcomprises a first approach to a surfaceof an optical storage mediumwith the movable partto reach a far-field working distance DF based on a focus control using an optical system for working in the far-field mode, and a subsequent approach to the surfaceof the optical storage mediumwhich is performed by lowering the far-field working distance DF to a smaller near-field working distance NF.