On at least one surface of a base metal plate of an \u03b1-\u03b3 transforming Fe or Fe alloy, a metal layer containing ferrite former is formed. The inlet has an opening smaller than the opening of a discharging outlet mouth formed in a cap, so that the outer layer’s body part may be squeezed to compress the air between the inner and outer layers, whereby the compressed air depresses the inner layer inwardly and radially to exude a liquid content outwards through the discharging outlet. The charge accumulation region is adjacent to at least one pixel cell of a pixel array. The invention can operate in a single axis or in two axes.