What is a hologram
8 12 2007A Hologram is a visual medium providing a high potential image in three dimensions (3D) making it instantly recognizable to the naked eye and uniquely resistant to counterfeiting. Holograms, with their high – quality, high – definition optical image are very effective in combating fraud.When viewed from different angles under any type of natural or artificial light, the hologram will diffract the beautiful colours of the spectrum (i.e colours seen in a rainbow), giving it an extraordinary appeal.
Apart from the three dimensional effect and the depth effect which are the basic features of the hologram, during the process of holographic recording (which is the same as the process of Master Origination) it is possible to create other effects such as the Animation Effect, The Dynamic Effect, The Kinetic Effect etc. and also to conceal code letters or numbers or secret images or incorporate Micro – Lettering one of the layers of the Hologram. These are some of the typical optical security features incorporated in Holograms to make them impossible to replicate. Some of these features can be viewed only with the aid of special viewing instruments or under special lighting conditions.
Holograms are of two major types viz. “Reflection Holograms” and “Transmission Holograms”. In the case of “Reflection Holograms” the course will be on the viewer’s side. The light will reflect off the hologram back to the viewer’s eye. “Reflection Holograms are most popular and are favoured / preferred by the general public. In the case of “Transmission Holograms”, the light has to pass through the hologram for the image to be seen. These holograms have to be illuminated from behind. Sometimes it may be difficult to position a light behind a hologram
When produced in volumes, holograms are very cost – effective i.e. only a small fraction of the packaging costs of a branded product. To produce in volumes, the impressions / images of the hologram are eventually embossed (i.e. printed) on the surface of the lacquered and metallised polyester film. The lacquering on the film is done to impart an additional security feature, namely the property of “Tamper –Evidence”. If anyone tries to remove a hologram, only the bare polyester film will come off in his fingers, leaving the impression image on the hologram or the surface on which it was originally affixed, this revealing the evidence of tamper with the hologram.
