To understand exactly what one excitation source of light is, it's helpful towards first know how fluorescence microscopy works. This strategy uses fluorescent dyes or proteins it emit light when excited by your specific wavelength of light. An excitation light supply emits this specific wavelength, what then excites your fluorophore and allows it to be visualized under a microscope.Traditionally, Mercury arc lamps were used as excitation light sources. However, they were not without their drawbacks. These lamps emitted UV radiation, which may damage samples and cause eye strain as part of researchers. Furthermore, these consumed a lot concerning power and have limited lifespan. Today, advancements at LED and laser technology have revolutionized excitation light sources, making them additional efficient and also effective.