Excimer lasers are laser systems that produce concentrated beams of light, usually in the ultraviolet region of the spectrum. The name “excimer laser” comes from the words “excited dimer,” which describe the material from which an excimer laser beam is generated. Excimer lasers generate laser beams in bursts of nanoseconds. They can produce laser beams at extremely low wavelengths, which makes them capable of generating the most powerful ultraviolet lasers out of any laser system.
Excimer lasers are useful in many applications for which other laser systems are not appropriate. Excimer lasers have proven to be very useful surgical tools, particularly in ophthalmological procedures. They are also sometimes used in procedures involving other tissue like bones and muscles; cosmetic procedures like stretch mark removal and psoriasis treatment may also make use of excimer lasers. The limitations and inherent risks associated with excimer lasers have limited their applications compared to other laser systems.
Excimer lasers require very high voltages in order to be generated. Also, their generation process involves the electrification of poisonous gasses which pose a hazard to professionals who work with them. Also, accidental exposure to concentrated ultraviolet light can cause serious health problems.
Laser is an acronym for light amplification by stimulated emission of radiation. All laser beams are amplified, focused light generated by the stimulated emission of radiation from a gain medium. Gain media are solid, liquid or gaseous materials, which, when excited by electricity, emit light radiation. This gain medium electrification process always takes place in an optical amplification enclosure.
In the case of excimer lasers, a combination of argon, krypton, xenon or other inert gasses with a reactive gas like fluorine is electrified within an enclosure. This combination, which is called a dimer, is excited by the electricity and releases photons as its electrons move between energy levels. Those photons are the source of light radiation; when produced in this way they are characterized by a very short wavelength.
If light radiation’s wavelength is short enough, it becomes ultraviolet. That light is then directed by several strategically placed reflective surfaces within the enclosure and then focused by a series of lenses to create the laser beam. In this way they are similar to other gas lasers like CO2 lasers and helium neon lasers; the difference between those systems is the wavelength of the light generated.