Editing Holography (section)

===Process===
When the two laser beams reach the recording medium, their light waves intersect and [[Interference (wave propagation)|interfere]] with each other. It is this interference pattern that is imprinted on the recording medium. The pattern itself is seemingly random, as it represents the way in which the scene's light ''interfered'' with the original light source – but not the original light source itself. The interference pattern can be considered an [[encoded]] version of the scene, requiring a particular key – the original light source – in order to view its contents.

This missing key is provided later by shining a laser, identical to the one used to record the hologram, onto the developed film. When this beam illuminates the hologram, it is diffracted by the hologram's surface pattern. This produces a light field identical to the one originally produced by the scene and scattered onto the hologram.