激光器使偶然的混杂频率的电磁辐射，变为一个或更多的高度强化和连续的紫外线、可见光或红外线辐射的分离频率仪器中的一种

Any of several devices that convert incident electromagnetic radiation of mixed frequencies to one or more discrete frequencies of highly amplified and coherent ultraviolet, visible, or infrared radiation.