What is luminous and how does it work

Photoluminescent pigments, which are not radioactive, are most commonly used today. Almost all modern watches have photoluminescence pigments applied to their hands, numerals, or dials. It works by absorbing light or UV and the stored energy releases visible light, which causes it to ‘glow in the dark’. Easily charged by exposing it to sunlight, or artificial light. The glow lasts about seven hours or so in the dark, depending on its quality and grade. Swiss brand Super-LumiNova brought the method into mainstream and today is one of the best and largest suppliers.

A phosphor-coated borosilicate glass encapsulates tritium in gas form. The tritium gas undergoes beta decay, which releases electrons, causing the phosphor to glow. Thats the basic rundown on how it is. Their luminescence doesn’t fade away after a few hours, and has a half life of 12 years. After about 24 years only a quarter of the radioactive material remains and the tritium gas tubes will no longer glow, requiring replacement.

When a current passes through a phosphor, electroluminescence takes place, resulting in the production of light. In a watch, a glass or plastic panel is coated with an electric conductor and a phosphor, then is mounted behind the dial. The phosphor reacts to an electric current delivered on demand, and acts as a backlight upon activation. The most common application for this is in digital watches.