I understand that laser stands for Light Amplification by Stimulated Emission of Radiation. However, I don’t understand how radiation comes into play when trying to create a light source with no divergence.
In: 4
Light is one of the many kinds of radiation. LASEL just doesn’t sound as good.
An excited atom wants to lose energy, and releases light when it does. In a laser, the excited atoms are created very carefully, so that more are excited than not. This is a special condition, which means that a photon is more likely to hit an excited atom than a normal atom.
When it hits the excited atom, it causes the atom to release another photon moving in the same direction, so now we have more photons. These continue hitting more excited atoms, releasing more and more photons and getting a good beam.
A laser can be “seeded” by having the first photon come from outside, or it can be self-starting, in which case two mirrors are used at either end to reflect light back and forth, allowing any “wrong” photons to quickly be lost while the “right” ones continue bouncing and generating more.
Latest Answers