Ink drop writing head

Claim 1

In a writing head for producing, on a record carrier, a high resolution character formed of drops of a writing fluid the head including a cover member and a plurality of writing fluid drop ejectors each composed of a fluid chamber communicating with a writing fluid reservoir, an ejector nozzle communicating with the chamber and constituted by an opening in the cover member, and an individually excitable pressure pulse generator arranged to apply pressure pulses to the fluid in the chamber for ejecting drops of writing fluid from the nozzle, the plurality of nozzles being aligned in a row and the head being arranged to be positioned with the row of nozzles facing the record carrier sO that fluid drops are ejected from the nozzles toward the record carrier the improvement comprising: at least one electrode member disposed adjacent all of said nozzles and mounted between said cover member and the location in which the record carrier writing surface is to be disposed during writing; and means for selectively applying a voltage differential between said cover member and said electrode member for producing an electric field which polarizes charge carriers contained in the electrically neutral writing fluid drops ejected from said nozzles and thus creates an attractive force between each such drop and said electrode member; and wherein said electrode member is configured to constitute means for causing the direction of such field to cause such attractive force to deflect the ejected writing fluid drips in a direction which is transverse to the row in which said nozzles are aligned and which has a component parallel to such row.