A chemical laser is a laser that obtains its energy from a chemical reaction. Chemical lasers can achieve continuous wave output with power reaching to megawatt levels. They are used in industry for cutting and drilling, and in military as directed energy weapons.

In a chemical laser, a suitable chemical reaction produces a stream of gas rich of excited atoms or molecules. Another gas is then injected to this stream, and either reacts with those particles, producing an excited molecule (hydrogen or deuterium with fluorine radicals in hydrogen fluoride laser), or takes energy from the excited particle (iodine molecules from singlet oxygen in COIL laser). These excited molecules then form population inversion, and in the optical resonator region of the laser then undergo stimulated emission, producing a powerful beam of coherent laser radiation.

Common examples of chemical lasers are the chemical oxygen iodine laser (COIL), all gas-phase iodine laser (AGIL), and the hydrogen fluoride laser and deuterium fluoride laser, both operating in mid-infrared region. There is also a DF-CO laser (deuterium fluoride-carbon dioxide), which, like COIL, is a "transfer laser".

Lasers