What is fluorescence and how does it occur?
Fluorescence occurs when an excited molecule relaxes to a lower energy state without changing electron spin. This relaxation happens through photon emission within nanoseconds.
Questions about Fluorescence
Short answers, pulled from the story.
Who discovered the phenomenon of fluorescence in 1560?
Bernardino de Sahagún recorded a strange observation about the wood of the narra tree in 1560. He described how an infusion made from this wood glowed with a blue light when exposed to sunlight.
When did George Gabriel Stokes clarify the distinction between fluorescence and phosphorescence?
George Gabriel Stokes finally clarified the distinction in 1852. He published a paper titled Refrangibility of Light where he described how fluorspar changed invisible violet light into visible light.
Which animals exhibit natural fluorescence according to recent studies?
Greeneye fish possess fluorescent structures that help them navigate deep waters. Pumpkin toadlets living in the Brazilian Atlantic forest have naturally fluorescent skeletons visible through their skin.
How do fluorescent lamps produce visible light?
An electric discharge causes mercury atoms to emit mostly ultraviolet light inside each glass tube. A coating called phosphor lines the tube interior and absorbs ultraviolet light before re-emitting visible light.