04864618 is referenced by 982 patents and cites 6 patents.

An automated transaction system employs a terminal for printing a value indicia, such as a postmark, on an article. The terminal contains a modular printer unit which has a printhead and a dedicated microprocessor physically permanently bonded together such that the printhead microprocessor cannot be physically tampered with without disabling the printhead. The modular printer unit includes a first supply of visible ink and a second supply of invisible ink, and an internal program for printing the value indicia with visible ink and an authentication code, which uniquely corresponds to the value indicia, with invisible ink. The invisible value indicia can be subsequently verified as authentic by machine reading of said invisible authentication code and comparing the authentication code for correspondence to the value indicia.

Title
Automated transaction system with modular printhead having print authentication feature
Application Number
935244
Publication Number
4864618
Application Date
October 17, 1988
Publication Date
September 5, 1989
Inventor
Stephen Bristow
Los Altos Hills
CA, US
Christopher B Wright
San Francisco
CA, US
Agent
Leighton K Chong
Assignee
Wright Technologies
CA, US
IPC
H04L 9/00
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