US 5,142,383 · Granted 1992-08-25

Holograms with discontinuous metallization including alpha-numeric shapes

Non-continuous reflective hologram or diffraction grating devices are provided in various forms for authenticating documents and things, such as those that contain visual information desired to be protected from alteration. Examples of such information include written personal data and photograph on a passport, driver's license, identity card, transportation pass, and the like. The reflective discontinuous hologram or diffraction device is formed in a pattern that both permits viewing the protected information through it and the viewing of an authenticating image or other light pattern reconstructed from it in reflection. The same master hologram or diffraction grating is made into distinct authenticaton devices by forming replicas thereof that have different patterns of reflective material which form distinct indicia, such as a different alpha-numeric character.

Curated and verified by the IsItPatented Editorial team