Editing Laser construction (section)

==Pump source==
The ''pump source'' is the part that provides energy to the [[laser]] system.  Examples of pump sources include electrical discharges, flashlamps, arc lamps, light from another laser, chemical reactions and even explosive devices.  The type of pump source used principally depends on the ''gain medium'', and this also determines how the energy is transmitted to the medium.  A [[helium–neon laser|helium–neon (HeNe) laser]] uses an electrical discharge in the helium-neon gas mixture, a [[Nd:YAG laser]] uses either light focused from a [[xenon flash lamp]] or [[Laser diode|diode lasers]], and excimer lasers use a chemical reaction.