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. 16, 1988
Filed:
Sep. 11, 1987
Marvin F Estes, Elba, NY (US);
Gerald J Smart, Rochester, NY (US);
Eastman Kodak Company, Rochester, NY (US);
Abstract
A transducer head, held in a fixed position as a preformatted disk is rotated a full revolution, reads any sector address accessible to the head. The addresses read come from a plurality of track revolutions that depend on the magnitude of the eccentricity of the disk. A computer, programmed with a least squares algorithm, first coordinates (1) data corresponding to the angular position of the disk each time an address is read, with (2) data corresponding to the actual radius of each address. The computer then transforms the array of data coordinated into a sinusoidal track eccentricity compensating signal of the form D cos (wt+E) where the amplitude D is a constant computed from the least squares algorithm corresponding to the distance between the center of the disk and its rotational axis, the phase E, which is also a constant computed by least squares, corresponds to the angle the center of the disk is from an angular reference position, and wt is a variable equal to the product of disk angular speed and time.