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. 13, 1992
Filed:
Jan. 12, 1990
Donald E Vandenberg, Brockport, NY (US);
Thomas W Dey, Springwater, NY (US);
William D Humbel, Rochester, NY (US);
John G Pitek, Rochester, NY (US);
Eastman Kodak Company, Rochester, NY (US);
Abstract
The Foucault or knife-edge method may be employed for testing an optical surface defined by an imaging device, for example, a mirror surface, to ascertain its characteristics, for example, whether or not it is a source of optical aberrations. To this end, the traditional Foucault knife-edge method typically employs a knife-edge that comprises a metal razor blade. The present method, in contrast, provides an improved Foucault method, and features a novel optical element suitable for employment in the method. The optical element comprises a transparent substrate, and a coating material that can adhere to at least a portion of the transparent substrate, thereby forming at least one knife-edge pattern.