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. 08, 1989
Filed:
May. 18, 1987
David M Orlicki, Rochester, NY (US);
William T Fearnside, Fishers, NY (US);
Eastman Kodak Company, Rochester, NY (US);
Abstract
Apparatus for sensing the instantaneous tracking position of a lens used in an optical read/write head for optically reading and/or writing information on an optical recording element (e.g. an optical disk). Such apparatus includes a variable inductance transducer which is positioned in close proximity to an electrically conductive, movably mounted lens support. As the lens is moved in a direction perpendicular to its optical axis, the lens support moves relative to the transducer, thereby varying the transducer's inductance. Circuit means responsive to the instantaneous transducer inductance provides a signal representative of the instantaneous lens position. Such signal is used to close a position feedback loop which maintains a fixed position of the lens axis relative to the optical axis of the head during sudden movements of the head (e.g. as occurs in during radial access in an optical disk recording system).