foszforeszcens

Foszforeszcens is a term used in chemistry and physics to describe a type of luminescence. Luminescence is the emission of light by a substance not resulting from heat. Foszforeszcens specifically refers to a process where a substance absorbs energy, such as from light, and then re-emits that energy as light over a period of time, often minutes, hours, or even days. This is in contrast to fluorescence, which emits light almost immediately after absorbing energy and stops emitting when the energy source is removed.

In foszforeszcens, electrons in the material are excited to a higher energy level. However, due to a specific quantum mechanical property called a spin flip, these electrons become trapped in a metastable state. They slowly decay from this state back to their ground state, releasing photons of light as they do so. This delayed emission is what makes foszforeszcens materials appear to glow in the dark after being exposed to light. Common examples include glow-in-the-dark toys, watch dials, and some safety signs. The color and duration of the glow depend on the specific chemical composition of the foszforeszcens material.