Holograms Reflection Hologram Transmission Hologram Plane Hologram Volume Hologram Embossed Hologram Integral Hologram Hybrid Hologram Computer Generated Hologram Multichannel Hologram Stereogram Dot Matrix Hologram 2D/3D Hologram 3D Hologram Image Hologram Transfer Hologram Rainbow Hologram

Hologram is a two or three dimensional photographic image produced by laser light. It was discovered by Gabor. The term hologram was coined from the Greek words holos, meaning "whole," and gramma, meaning "message." The process by which the image is recorded is called holography.

A hologram contains information about the size, shape, brightness and contrast of the object being recorded. This information is stored in a very microscopic and complex pattern of interference. The interference pattern is made possible by the properties of light generated by a laser.

Laser light is used more often because the light from a laser is of one color and leaves the laser with one wave in perfect step with all others. Such a light that is highly directional and of one colors is called coherent.

The hologram presents a true three dimensional recreation of the original object when re-illuminated and viewed under normal light. For the observer, the perception of depth is virtually indistinguishable from reality.

Holograms are available in assorted styles and types. Each hologram requires it's own individual technique for production. Some holograms require a laser to view them, others rely only on regular light. Some holograms show motion, and some change images as you move by them. Holograms can be in full-color, change color and even project their image out in space toward you when you view them.

Properties of Holograms

• Sensitivity to vibration - Holograms record specific information about light at the level of individual light waves. Thus, the holographic plates are sensitive enough to record a single wavelength of light, 650 nm for red laser light.
• Divisibility - A hologram can be divided into small pieces that still retain the entire image of the object. The object's wavefront is preserved throughout the hologram, and can be viewed from a tiny piece of the whole.

Applications of Holograms

• Art, science and technology
• Used on certain product packaging
• Used for labelling
• Embellishment on printed media
• On credit cards and driving license to help stop counterfeiting
• Used in airplanes to provide the pilot with critical information
• Also used for artistic expression
• Security applications