Lets learn about lasers!
Lasing Medium / Gain Medium – The material which forms the laser light.
Pump – The energy source needed to induce the population inversion.
Population Inversion – The act of causing the electrons in the lasing medium to jump to higher energy states.
Meta-Stable – A short period of stability.
Stimulated Emission – When an electron drops to a ground state and emits a photon as a result of another photon passing by it. Both photons are coherent.
Spontaneous Emission – When an electron drops to a ground state and emits a photon after a short time in a meta stable state.
The lasers in the video are DPSS Lasers (Diode Pumped Solid State)
An Infrared Aluminum Gallium Arsenide diode laser emits 808nm photons. These pump a Neodymium-Doped Yttrium Orthovanadate or Neodymium-Doped YAG crystal which emits 1064nm laser light. This light is Freq doubled using Potassium Titanyl Phosphate crystal to become 532nm, a beautiful green color