Ultraviolet priming of triboluminescence

Triboluminescent (TL) materials may be used in embedded structural health monitoring systems for composites. Damage excites a TL emission, providing in situ, real-time damage monitoring. For analysis, the TL light is converted into an electrical signal and transferred to a computer. For precise data analysis, a high signal-to-noise ratio is desired. Therefore, it is of interest to increase the intensity of TL emissions. This work shows ultraviolet light may be used to prime the low-velocity TL emissions of ZnS:Mn, causing the next TL emission to be over five times brighter than an unprimed TL emission. The priming effect decays quickly, with TL emissions returning to unprimed intensity after about ten impacts.