Charge compensation circuit for an electrostatic writing head

Abstract

A power module including an RC circuit is uniquely associated with each of a plurality of electrodes of an electrostatic print head to individually control the rate of charge decay of a voltage disposed thereon. The resistor of the RC circuit is a potentiometer that may be manually adjusted to obtain an optimal decay rate. A paper supply roller and take-up roller accurately position dielectric material, such as a paper web, adjacent to the electrodes of the print head, which is located between the rollers. The electrodes are typically a plurality of wires. The print head moves across the width of paper web to dispose thereon a plurality of charge areas corresponding to a strip of a latent image. Control circuitry synchronizes the movement of the print head and the web to produce a plurality of abutting strips of charge areas, producing a complete latent image. A toner applicator is positioned downstream from the print head to dispose ionized toner particles which adhere to the plurality of charge areas, thereby producing a visible image.