3D Holograms Detect Fake Signatures

Security Hologram ... Holograms are classified into different types with reference to the degree of level of optical security incorporated in them during the process of master origination... The different classifications are described below: 2D / 3D "hologram" images These are by far the most common type of hologram - and in fact they are not holograms in any true sense of the words... The matter of the middle ground in the case of the two-layer holograms are usually superimposed over the matter of the background of the hologram...

Holography ... The development of the laser enabled the first practical optical holograms that recorded 3D objects to be made in 1962 by Yuri Denisyuk in the Soviet Union and by Emmett Leith and Juris Upatnieks at University of Michigan, USA... Various methods of converting the variation in transmission to a variation in refractive index (known as "bleaching") were developed which enabled much more efficient holograms to be produced...

Holographic Interferometry ... Holography enables the light field scattered from an object to be recorded and replayed. If this recorded field is superimposed on the 'live field' scattered from the object, the two fields will be identical...

Holographic Data Storage ... By adjusting the reference beam angle, wavelength, or media position, a multitude of holograms (theoretically, several thousand) can be stored on a single volume...

Rainbow Hologram ... The holograms found on credit cards are examples of rainbow holograms. How a rainbow hologram works Figure 2 shows an optical arrangement for making a rainbow hologram...