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:
Sep. 19, 1990
Paul M Tannenbaum, Wilmington, DE (US);
Michael P Milone, Elmer, NJ (US);
Dennis B Fowler, Bear, DE (US);
E. I. Du Pont de Nemours and Company, Wilmington, DE (US);
Abstract
A method and apparatus for analyzing the appearance features of a surface with a spatially coherent beam of uniformly distributed collimated polychromatic light that is directed through a beam limiting means (or mask) and onto the surface at an acute angle of incidence. A scanned imaging detector, translatable through a sequence of focal plane positions along the optic axis between the mask and surface, measures the reflectance values associated with the scanned pixel intensities. After standardization, the scan intensity values are Fourier transformed into the spatial frequency domain to obtain an optical transfer function (OTF) and power and amplitude spectra. The visual spatial frequency response characteristic V(f) and standard psychophysical methodology is applied to mathematically determine surface appearance attributes such as orange peel, microwrinkle, cracks and crazes, distinctness of image (DOI), gloss, haze, contrast, luster, fog and texture.