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:
Feb. 13, 2001
Filed:
May. 15, 1998
Applicant:
Inventors:
James Gordon Charters Smith, High Wycombe, GB;
Martin Cooper, Marlow, GB;
Assignee:
Gersan Establishment, Liechtenstein, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B44C 1/22 ; B23K 2/600 ;
U.S. Cl.
CPC ...
B44C 1/22 ; B23K 2/600 ;
Abstract
In order to produce on the table of a diamond gemstone (,), an information mark which is invisible to the naked eye using a ×10 loupe, an ultraviolet laser (,) having a wavelength of 193 nm is used in association with a mask (,) to irradiate the surface of the stone (,) at a fluence of less than 2 J/cm,per pulse and with not fewer than 100 pulses, in the presence of air which reacts with the diamond (,) and causes the mark to be formed without any darkening which is visible when viewing using a microscope.