Final answer:
Holography is the process of producing holograms, which are three-dimensional images. It uses light interference or wave optics, unlike normal photography which uses geometric optics. Construction of a hologram involves exposing photographic film to a split laser beam and an object, while reconstruction involves passing a laser beam through the hologram to form a real and virtual image of the object.
Step-by-step explanation:
Holography is the process of producing holograms, which are three-dimensional images. Unlike normal photography, holography uses light interference or wave optics instead of geometric optics. A hologram is created by splitting coherent light from a laser and directing part of it onto an object, while the remaining light illuminates a piece of film known as the reference beam.
The light scattered from the object interferes with the reference beam, resulting in constructive and destructive interference. The exposed film contains a complex interference pattern, and where the interference was constructive, the film is darkened.
When it comes to the construction and reconstruction of a hologram, a suitable diagram can be helpful in understanding the process.
The first step in creating a hologram is the construction, or recording, of the holographic interference pattern. This is achieved by exposing photographic film to the split laser beam and the object. The resulting interference pattern is then stored on the film.
The second step is the reconstruction of the hologram. To do this, a laser beam of the same type as the one used to record the hologram is passed through the hologram.
The hologram acts as a diffraction grating, diffracting the laser beam and producing the same interference pattern as the object that was used to record the hologram. As a result, both a real image and a virtual image of the object are formed, allowing the viewer to see the hologram from different perspectives.