04765656 is referenced by 167 patents and cites 12 patents.

The present invention relates to a data carrier (identification card, bank card, credit card, etc.) in which information is provided in an inner volume area by means of a laser beam, the information being visible in the form of changes in the optical properties of the carrier material due to an irreversible change in the material caused by the laser beam and to a method for producing the data carrier and for testing it.

Title
Data carrier having an optical authenticity feature and methods for producing and testing said data carrier
Application Number
6/918921
Publication Number
4765656
Application Date
October 15, 1986
Publication Date
August 23, 1988
Inventor
Wittich Kaule
Emmering
DE
Joseph Lass
Munich
DE
Erwin Lob
Munich
DE
Hansjurgen Merkle
Munich
DE
Alexander Hierweger
Rottach-Egern
DE
Wolfgang Becker
Neubiberg
DE
Agent
Bacon & Thomas
Assignee
GAO Gesellschaft fur Automation und Organisation mbH
DE
IPC
B42D 15/00
View Original Source