Glow in the dark wiki

Phosphorescence is a type of photoluminescence related to fluorescence. When exposed to light radiation of a shorter wavelength, a phosphorescent substance will glow, absorbing the light and reemitting it at a longer wavelength. Unlike fluorescence, a phosphorescent material does not immediately reemit the radiation it absorbs. Instead, a phosphorescent material absorbs some of the radiation energy and reemits it for a much longer time after the radiation source is removed.

In a general sense, there is no distinct boundary between the emission times of fluorescence and phosphorescence i. Whereas fluorescent materials stop emitting light within nanoseconds billionths of a second after the excitation radiation is removed, phosphorescent materials may continue to emit an afterglow ranging from a few microseconds to many hours after the excitation is removed.

How does glow in the dark work

There are two separate mechanisms that may produce phosphorescence, called triplet phosphorescence or simply phosphorescence and persistent phosphorescence or persistent luminescence :. Everyday examples of phosphorescent materials are the glow-in-the-dark toys, stickers, paint, and clock dials that glow after being charged with a bright light such as in any normal reading or room light.

Typically, the glow slowly fades out, sometimes within a few minutes or up to a few hours in a dark room. The study of phosphorescent materials led to the discovery of radioactive decay.

Glow in the-dark meaning synonyms

It was first recorded in The term phosphor had been used since the Middle Ages to describe minerals that glowed in the dark. One of the most famous, but not the first, was Bolognian phosphor. Around , Vincenzo Casciarolo discovered a " lapis solaris " near Bologna, Italy. Once heated in an oxygen-rich furnace , it thereafter absorbed sunlight and glowed in the dark.

In , Hennig Brand isolated a new element that glowed due to a chemiluminescent reaction when exposed to air, and named it " phosphorus ".