Last time I have discussed about the holography and written that it is a two stage process. The first stage is recording of hologram in the form of interference pattern and in the second stage, the hologram acts as a diffraction grating for the reconstruction beam and the image of the object is reconstructed for the hologram.
Do you know what is the difference between hologram and photograph? If no, then let us discuss:
Difference between Holography and Photography
1. In photography, only intensity is recorded so photography produces two dimensional picture of the object whereas in holography, both intensity as well as phase of light wave is recorded, thus holography gives three dimensional picture of the object.
2. Negative is prepared first in photography whereas in holography no negative is required. The hologram is negative and image it gives is positive.
3. If the hologram is broken into parts, each part is capable of reconstructing the entire object. But in photography the destruction of even very small portion of negative or photography results in a irrepareable loss of information.
4. Holography has high information capacity as compared to photography.