5.2.4.2.2 lasers Lasers, light amplification by stimulated emission of radiation, emit electromagnetic radiation in either the UV, IR, or visible spectrum. The wavelength and frequency of the emitted light depend on which spectrum is used. In the biomedical field, the laser has been used for microsurgery and for measuring immunoglobulins and other elements in the blood. Lasers are becoming increasingly popular in surgery. The most typical locations for lasers in the hospital are in radiology departments where they are used to help align patients for radiographic treatment and surgical areas where they have a wide variety of applications.
Lasers cause damage because they focus large amounts of light energy on a small surface area.
The cornea and lens of the eye can focus the light from a laser of visible wavelength so that the light energy may cause lesions because it is more concentrated when it strikes the retina. In some cases, the damage to the retina is not reversible. The light from UV lasers may also cause damage by heating the surfaces of tissues and denaturing proteins. When lasers strike the skin, the effects may range from erythema to blistering and charring. The extent of the damage depends on the wavelength, power, and duration of exposure.