Certain materials possess fluorescent properties, absorbing ultraviolet (UV) light invisible to the human eye and re-emitting it as visible light. This phenomenon causes them to appear to “glow” under a black light, which emits long-wave ultraviolet (UV-A) radiation. Common examples include white clothing, certain plastics, and fluorescent paints or dyes, often appearing vibrant shades of blue, green, yellow, pink, and orange. Tonic water, due to its quinine content, emits a distinctive blue-white glow.
The ability of substances to fluoresce under UV light has numerous practical applications. It is utilized in forensic science for detecting bodily fluids and counterfeit currency, in art conservation for identifying repairs and authenticating paintings, and in various entertainment contexts, such as theatrical productions and nightclubs, to create visually striking effects. The discovery of fluorescence dates back to the 16th century, with significant contributions from scientists like Nicols Monardes and Robert Boyle. Early observations paved the way for later understandings of the underlying scientific principles and the development of practical applications.
