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:
Feb. 16, 1999
Filed:
Nov. 22, 1996
Boris A Shtipelman, Rochester, NY (US);
James A Barnard, Scottsville, NY (US);
Charles J Simpson, Rochester, NY (US);
Eastman Kodak Company, Rochester, NY (US);
Abstract
An optical disc is disclosed having a substrate in which data can be written on or read from, such optical disc has a transparent cover sheet which is held at a desired spacing from the substrate at least at an inner radius and an outer radius. In order to prevent the transparent cover sheet from deflecting due to pressure differences between the outside atmosphere and the air in the space between the substrate surface and the transparent cover sheet, a plurality of air passages in the transparent cover sheet are provided near an inflection point where on one lateral side of the point the transparent sheet will bulge and on the other lateral side it will be depressed due to centrifugal force acting upon air entrapped between the transparent cover sheet and the substrate surface during disc rotation in an optical disc drive. This arrangement equalizes the pressure in the air space between the transparent cover sheet and the substrate surface and the outside atmosphere.