Abstract

An entirely new method of storing confidential data is presented. The method is based on sandwich holography, and its main principle is the following: The basic state of a surface is recorded in one plate of a sandwich pair; in the other plate the same surface is recorded slightly deformed. When the two holograms are combined an interference fringe pattern is formed. By controlling the deformation of the surface it is possible to obtain exactly the interference pattern wanted. This controlled pattern can be used to create information that is either directly readable digital information or a binary coded information, suitable to automatic readout. The data stored in the holograms are not possible to read out from one hologram alone, but the two holograms must be put together to make the information available. The system is primarily meant to be applied on ID cards but can also be used for other applications where data have to be stored securely.

© 1979 Optical Society of America

Sandwich hologram interferometry. 5: Measurement of in-plane displacement and compensation for rigid body motion

Nils Abramson and Hans Bjelkhagen
Appl. Opt. 18(16) 2870-2880 (1979)

Pulsed sandwich holography

Hans Bjelkhagen
Appl. Opt. 16(6) 1727-1731 (1977)

Virtual holography: a method of source and channel encoding and decoding of information

O. Ersoy
Appl. Opt. 18(15) 2543-2554 (1979)

Hologram repositioning by an interferometric technique

O. D. D. Soares
Appl. Opt. 18(22) 3838-3840 (1979)

Optical security system for the protection of personal identification information

Yang-Hoi Doh, Jong-Soo Yoon, Kyung-Hyun Choi, and Mohammad S. Alam
Appl. Opt. 44(5) 742-750 (2005)