How Do Blacklights Make Things Glow?

Black lights emit ultraviolet (UV) light, which is mostly invisible to the human eye. They use special filters to allow only UVA and a small amount of visible light to pass through, creating a purplish glow. Certain materials, known as phosphors, absorb this UV light and re-emit it as visible light, causing them to glow. This property is used in various applications, such as forensics, diagnostics, and security, as well as in decorative settings.

What is the primary function of a black light?

Explain how phosphors contribute to the glowing effect under a black light.

What are some common materials that contain phosphors?

How can black lights be used in forensic investigations?

Describe the role of black lights in detecting counterfeiting.