Whether you're spending time with friends in a laser tag arena, venturing through the narrow passageways of a haunted house, or simply just watching your favorite TV show, black lights never cease to amaze. There's something fun and mysterious about revealing secrets and hidden messages with this strange purple light. But how do black lights work? (Hint: It's not magic.)
The signature glow produced by black lights requires two separate things: A source of ultraviolet light and an area coated with UV-reactive phosphors. The origin of the light is a bulb, whether incandescent, fluorescent, CFL, or LED. You'll find phosphors—a loose grouping referring to special compounds and minerals—in and on all kinds of things: Highlighters, soap, rocks, glow-in-the-dark toys, and even your teeth. When ultraviolet light hits a phosphor, the phosphor glows in a phenomenon called luminescence.