Controlling light discharged by a phosphorescent material

A material that phosphoresces may be controlled and the phosphorescence may be terminated when desired. A phosphorescing material may be exposed to an energy source that causes the material to stop phosphorescing. Thus, a pattern may be written on a surface, which is phosphorescing using a coherent energy source. The written pattern, represented by darkened regions, may be recognized by users as a symbol, a graphics or text.