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:
Oct. 10, 2000
Filed:
Jul. 24, 1998
Gerard E Van Rosmalen, Eindhoven, NL;
Marcus J Willems Van Dijk, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
An optical scanning device for scanning an optically readable record carrier (1) includes a radiation source (5), a radiation-sensitive detection system (7), and an optical scanning unit for focusing a scanning beam (3) produced by the radiation source to a scanning spot (9) on the record carrier. The scanning unit including a lens system having an optical axis (13), which lens system includes a first lens unit having a main lens (15) and a second lens unit having an auxiliary lens (17). The scanning device further includes a first detection unit involved in detection of the main lens with respect to the record carrier, and a second detection unit involved in detection of the auxiliary lens. The scanning unit further includes a first electrical drive unit for moving the first lens unit in dependence upon a signal supplied by the first detection unit, and a second electrical drive unit for moving the second lens unit with respect to the main lens in dependence upon a signal supplied by the second detection unit. The second drive unit includes a first part and a second part which cooperates with the first part via an air gap (51). The first part is secured to the first lens unit and the second part is secured to the second lens unit. In order to counteract spherical aberration and/or coma and/or astigmatism during scanning the second detection unit includes a position and orientation detector system for detecting the position and orientation of the auxiliary lens with respect to the record carrier during scanning.