Hologram are a bit like photographs that never die. They’re sort of photographic ghosts they look like three dimensional photos that have somehow got trapped inside glass, metal. When you tilt a credit card hologram, you see an image of something like a bird moving “inside”the card. The hologram itself is not an image and it is usually unintelligible when viewed under diffuse ambient light.It is an encoding of the light field as an interference pattern of seemingly random variations in the opacity, density profile of the photographic medium.
The theory of holography was developed by Dennis Gabor in 1947. The development of laser technology made holography possible.
A holographic image can be seen by looking into an illuminated holographic print or by shining a laser through a hologram and projecting the image onto a screen.
Holography is the science and practice of making holograms.
How to Work Hologram?
Laser light is much purer than the ordinary light in a torch beam. In a torch beam, all the light waves are random and jumbled up. A more flexible arrangement for recording a hologram requires the laser beam to be aimed through a series of elements that change it in different ways.
When the two laser beams reach the recording medium, their light waves intersect and interfere with each other. It is this interference pattern that is imprinted on the recording medium.
A hologram represents a recording of information regarding the light that came from the original scene as scattered in a range of directions rather than from only one direction, as in a photograph.
This allows the scene to be viewed from a range of different angles, as if it were still present. A holographic recording requires a second light beam to be directed onto the recording medium.
Holography is the next stage of photography and conventional film and its three-dimensionality creates completely new possibilities for use, such as for product presentation.particularly interesting point unlike 3D television or Virtual Reality which is an incredible advantage for use at trade fairs, exhibitions, and similar events. This projector, which makes the holographic 3D projection possible.