
Fluorescent—or “neon”—colours do this, too, however they’ve a further trick. Fluorescent colours additionally take in and convert ultraviolet rays, that are invisible, and convert them into seen gentle. Fluorescence shifts power within the incident illumination from shorter wavelengths to longer (similar to blue to yellow) and thus could make the fluorescent colour seem brighter (extra saturated or lighter in luminance) than it might probably be by reflection alone. The absorbed power excites electrons within the pigment molecules to the next power stage, which then chill out again to their floor state by emitting gentle at an extended wavelength than that absorbed, leading to a visual glow
Ultraviolet gentle is normally current in out of doors gentle, whether or not direct daylight or overcast. With no supply of short-wavelength gentle (like a black gentle), the fluorescent pigments will not stand out. As quickly as you add an ultraviolet gentle supply, the fluorescent pigments will seem to glow, whereas typical colours stay boring and hardly seen. If a topic is lit solely by ultraviolet gentle and no seen wavelengths, fluorescent colours will seem to glow magically in the dead of night.
—