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:
Dec. 16, 2003
Filed:
May. 24, 2000
Applicant:
Inventor:
Al Gilbertson, Albany, OR (US);
Assignee:
EightStar Diamond Company, Inc., Cotati, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01N 2/100 ;
U.S. Cl.
CPC ...
G01N 2/100 ;
Abstract
The invention is a multicolored reflecting disc that can be mounted to a lens for grading gemstone brightness and symmetry. The disc has an opening or aperture through which the gemstone is viewed on the object side of the lens. The aperture is surrounded by multicolored concentric rings which face the gemstone. Light reflecting from the multicolored rings creates specific colors on the gemstone that allow symmetry and brightness of the tone to be evaluated.