A variable modulator assembly includes a deformable layer adhered to a compliant layer surface, and an n-phase electrode configuration, n>2, adhered to an opposite surface of the compliant layer. In one illustrative example, a sensor stack structure which includes an electrically conductive spacer layer is formed over a first shield layer. The shaft formed of a metallic material inserted into the conductive roller and configured to be given a voltage from a power supply. The scanning electrodes are successively brought to a selected state by applying the selection signal voltage to each scanning electrode in a scanning period set for the scanning electrode, while a rewriting signal voltage corresponding to each scanning electrode in the selected state is applied to each signal electrode. Sales transactions are initiated in the sales transaction area of a custom enterprise site and transmitted over the custom extranet. The main unit has a weight which can be supported by one arm and is provided with handle means to be grasped by one hand.