Demonstration of static electricity induced luminescence.

Can we visualise static electricity, which everyone in the world knows about? Since static electricity is generated by contact or peeling, it may be a source of malfunction of electronic components, whose importance is steadily increasing, and even cause explosion and fire. As static electricity is invisible, makeshift measures of static electricity are taken on various surfaces; there is also a common view that it is hard to take effective measures. Here we present a specific luminescent material, SrAlO: Eu, which emits light at excitation by an electrostatic charge in the air. Till now, in the interaction between electricity and luminescent materials, it was considered that emission of light is enabled by accelerated particles colliding with the luminescent material in vacuo. There have been no reports on luminescent materials being responsive to low-energy electrostatic charges under atmospheric pressure. Using SrAlO: Eu luminescent material discovered by us, we succeeded for the first time in static electricity visualisation in the form of green light. In addition to the fact that such static electricity induced luminescence assists in solving electrostatic-related problems in the industry, it also provides a new measurement method that facilitates the observation of previously invisible electric charges in the air.