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:
May. 10, 1994
Filed:
Apr. 01, 1992
John N Pike, Pleasantville, NY (US);
Materials Technologies Corporation, Monroe, CT (US);
Abstract
An apparatus and method measures the roughness or some other surface dimension by transmitting a beam of light through a grating member at an angle of incidence relative to the grating member. The grating member has a plurality of parallel opaque bars and adjacent transparent bars. The beam of light forms a multiple line shadow pattern on the surface below the grating member formed by the shadows of the opaque bars of the grating member. A camera records the multiple line shadow pattern, and the recorded pattern is superimposed on a plurality of parallel, equally spaced scan lines oriented perpendicular to the shadow lines. The distances between the points at which adjacent shadow lines cross each respective scan line are measured to determine the roughness or some other surface dimension.