04667087 is referenced by 217 patents and cites 1 patents.

A credit card resistant to unlawful use has a code, indicative of the owner's account number hidden beneath an opaque shield. The card has a keyboard and microprocessing components electrically connected to the shield. Insertion of correct entries, e.g. an owner's personal identification number, into the keyboard results in application of an electric signal to the shield to render it transparent in order that the code may be viewed by another person or by a machine. Erroneous attempts to operate the keyboard beyond a predetermined standard disable the keyboard from further operation.

Title
Secure credit card
Application Number
6/846214
Publication Number
4667087
Application Date
March 31, 1986
Publication Date
May 19, 1987
Inventor
Max A Quintana
4882 Tucson St., Denver, 80239
CO, US
Agent
Dowell & Dowell
Assignee
Alton Y Lennon
NC, US
Bernard L Morgan
NC, US
Robert E King
NC, US
Max A Quintana
CO, US
IPC
G06K 5/00
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