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:
Sep. 21, 2004
Filed:
Aug. 31, 2000
Applicant:
Inventor:
Al Gilbertson, Carlsbad, CA (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 surface that can be mounted beneath a lens for facilitating the grading of a gemstone's brightness and symmetry. The multicolored reflective surface may be a disc that has an opening or aperture surrounded by multicolored concentric rings through which the gemstone is viewed on the object side of the lens. Alternatively, the multicolored reflective surface may be a cylinder formed of multicolored bands through which the gemstone is viewed. Light reflecting from the multicolored rings or bands creates specific colors on the gemstone that allow symmetry and brightness of the stone to be evaluated.