06471878 is referenced by 30 patents.

A method for forming a radio frequency responsive target formed of a pattern of thin dipoles, each of which has a position and angular orientation within the pattern, which produce a composite analog radio frequency signal in response to an interrogating signal. A first metallic film layer is deposited on top of a non-conductive substrate, an etchant resistant pattern correspondent to the thin dipole pattern is deposited on top of the first metallic film layer, and a second metallic layer occupying the first metallic layer in at least one area without etchant is applied on top of the first metallic film layer. The etchant resistant pattern is removed to expose portions of the first metallic film layer, and the second metallic layer and the exposed portions of the first metallic film layer are etched simultaneously.

Title
Method for forming a radio frequency responsive target and apparatus for verifying the authenticity of same
Application Number
9/328651
Publication Number
6471878 (B1)
Application Date
June 9, 1999
Publication Date
October 29, 2002
Inventor
G William Hurley
Cattlet
VA, US
Morton Greene
Arlington
VA, US
Agent
ReedSmith
US
Agent
Thomas J McWilliams
US
Assignee
Gordion Holding Corporation
VA, US
IPC
H01B 13/00
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