Novel approach to dynamic imaging of stress distribution with piezoluminescence

The dynamic imaging of stress distribution has been realized by developing remarkably strong piezoluminescence films of ZnS doped with Mn. A simulation result confirms that such a piezoelectric image successfully reflects the stress distribution. This piezoluminescence of ZnS:Mn can be explained by a model based on the superposition of piezoelectric effect and electroluminescence. It is proposed that the high orientation and crystallization of the ZnS:Mn film give higher piezoelectric voltage on the opposite sides of the nano-sized grains of ZnS, which leads to a higher efficiency of electroluminescence, and finally as a total effect, providing a higher ML intensity.