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:
Apr. 07, 1987
Filed:
Aug. 06, 1984
Peter A Jansson, Hockessin, DE (US);
Michael J Merrill, New Castle, DE (US);
Daniel K Owens, Circleville, OH (US);
Barry Rubin, Glen Mills, PA (US);
E. I. Du Pont de Nemours and Company, Wilmington, DE (US);
Abstract
An automated system is used for the inspection of a transparent film which has been metallized by vaporizing a metal so that it impacts the film's surface at a preselected angle, wherein the metallized film sample is illuminated with a light source, and the transmitted light is passed through a microscope to a video camera, which produces a videoscan. The videoscan is digitized, stored in a computer memory, and processed pixel by pixel by the computer which calculates asperity height distribution from the number and lengths of metallizing shadows caused by asperities on the film surface. This method is especially useful for inspecting film to be used for recording devices, especially for video tapes, where accurate information on the asperity height distribution is required.