What is the difference between a black light and a normal light bulb?
Black lights come in two varieties — fluorescent tube and incandescent bulb. Each type works slightly differently, but both are very similar to their normal white-light cousins. Fluorescent tube lights are glass tubes that contain a near-vacuum with a little mercury vapor. When electricity is passed through the tube and reacts with the mercury, it creates light. The mercury atoms emit energy in the form of light photons. These photos are mostly in the ultraviolet (UV) range of the light spectrum. We can’t see this light, so a white phosphor coating on the light tube is used to convert the UV energy into visible light. A black light works the same way, except the tube is made of dark blue glass, and it is coated with a special phosphor that blocks visible light and harmful UV rays. Only th
