What are Holograms?

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Holograms are three -dimensional photographs, which have depth, length and breadth. When a hologram is lit by a laser light, it produces a three-dimensional image of an object. One can get a different view of the object as one walks around. TO make a hologram, the object is lit by light from a laser. This light reflects from the object and strikes a photographic plate placed nearby. At the same time, the laser beam is split so that it also reflects from mirrors and strikes the plate directly. Interference between the two beams produces a pattern on the plate that is not recognizable as a photograph. This pattern is called the hologram. 

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