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:
Jul. 29, 2003
Filed:
May. 29, 2002
Applicant:
Inventor:
John R Sambles, Exeter, GB;
Assignee:
Qinetiq Limited, Farnborough, GB;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02B 5/18 ;
U.S. Cl.
CPC ...
G02B 5/18 ;
Abstract
A surface capable of supporting surface charge oscillations and exhibiting a profiled grating, said profile comprising at least two superposed periodic profiles. The surface has applications as radar absorber and authentication devices. Also disclosed is a method of detecting the authenticity of an object comprising providing a surface as described above claim adjacent to or on the object, illuminating said surface with radiation from at least one angle and determining the reflectivity characteristics and comparing this with reflectivity characteristics of a reference surface.