Light & Color

Fluorescent Tube

In this exhibit, half of the FLUORESCENT TUBE is clear, while the other half is coated with white phosphor. When you look at the different parts of the tube with a spectroscope, the clear end shows specific spectral colors. The coated end has these colors plus an additional continuous spectrum of colors due to the phosphors. The mercury gas in a fluorescent tube produces strong ultraviolet light, which the phosphor coating absorbs and re-emits in the continuous spectrum. It is this process which is called fluorescence.