Tritium radioluminescence Tritium radioluminescence Tritium radioluminescence is the use of gaseous tritium, a radioactive isotope of hydrogen, to create visible light. Tritium emits electrons through beta decay and, when they interact with a phosphor material, light is emitted through the process of phosphorescence. The overall process of using a radioactive material to excite a phosphor and ultimately generate light is called radioluminescence. As tritium illumination requires no electrical energy, it has found wide use in applications such as emergency exit signs, illumination of wristwatches, and portable yet very reliable sources of low intensity light which won't degrade human night vision. Gun sights
Tritium radioluminescence to phosphoresce. During manufacture, a length of borosilicate glass tube that has had the inside surface coated with a phosphor-containing material is filled with radioactive tritium. The tube is then sealed at the desired length using a carbon dioxide laser. Borosilicate is preferred for its strength and resistance to breakage. In the tube, the tritium gives off a steady stream of electrons due to beta decay. These particles excite the phosphor, causing it to emit a low, steady glow. Tritium is not the only material that can be used for self-powered lighting. Radium was used to make self-luminous paint from