Plasma inverter
A plasma inverter was a technological device that, hooked up with a modified laser scanner, could produce a plasma shock. 

In 2368, Geordi La Forge combined the two devices and, through a small hole created by means of a micro-optic drill, was able to send enough plasma through the hole to temporarily plasma-shock Deanna Troi and Miles O'Brien who were taken over by Ux-Mal criminals. ()
Technology

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