Black Light Poster Basics
Black light posters are powered by flourescent inks that operate to ultraviolet or "dingy" glossy. Under habitual circumstances, these posters case peppy and brilliant, however when exposed to ultraviolet clear, they truly glow in the clouded. Fluorescence is not unusual---white T-shirts, material washed in positive essence brighteners, object fluids and many other matters besides glow under inklike lights.
Ultraviolet Light
Ultraviolet (UV) light is a frequency of light just above the visible spectrum. Normal sunlight contains UV light, too as visible light. A red black light poster, For instance, will usually look red in both daylight and under a UV light.
When a molecule of a fluorescent material such as the ink in a black light poster is struck by a photon of ultraviolet light, it absorbs the photon. This raises the energy level of one of its electrons. The electron is unstable at the high energy level, and quickly releases the photon again, this time at a visible frequency. The inks in black light posters usually fluoresce in about the same color they normally reflect. Black lights are designed to emit as much black light as possible. They look purple, since they also emit some purple light. Purple light is at the far end of the visible spectrum, a slightly lower frequency than black light.
