Existing plasma generators are already widely used for such applications and air-conditioning devices. However, a high voltage is needed to be input to their plasma-generating part. The high voltage is electrically generated by inputting a high-frequency voltage to a coil-type transformer, increasing size and cost.

The plasma generator that TDK developed this time uses a "principle that had not been put into practical use," the company said. The company realized a "Rosen-type" plasma generator by using a piezoelectric device equipped with comb-type electrodes inside. It uses the deflection generated by applying a voltage and the voltage generated by the deflection.

While an input energy of 100-10,000W was required in the past, the new generator requires an input energy of about 10W (about 1A at a voltage of 12V), eliminating the need for safety measures against high voltage. Moreover, the temperature of the area surrounding the plasma-generating part does not become too high (e.g. several hundred degrees C) and becomes 50°C or lower. The development of the piezoelectric material, etc was conducted by TDK Electronics Co Ltd (previously Epcos AG).

The small, light-weight device directly turns gas into plasma. (source: TDK)

The mounting of the piezoelectric device (source: TDK)

A potential customer that focused on the deodorizing function realized by the generation of ozone requested to equip a trash bin with the plasma generator. It reduces the odors of food waste, diapers, etc and kills bacteria, TDK said.

Original Japanese article