A signal beam or object beam is one of at least two
laser
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word ''laser'' originated as an acronym for light amplification by stimulated emission of radi ...
beams used to write
holograms. The signal beam is the beam that carries the information to be stored in the hologram. In the case of a holographic picture, this beam is reflected off the object being recorded, into the media. In the case of holographic data storage, the beam has some kind information encoded into it (for instance, it can be sent through a
transparency or a
spatial light modulator).
The other beam necessary to write a hologram is the
reference beam.
Holography
Laser applications
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