Bias shield and method of developing a latent charge image

Abstract

The invention includes an apparatus,for developing a latent charge image formed on a photoreceptor,disposed on an interior surface of a faceplate panel,. The apparatus,comprises a developer tank,having a sidewall,closed at one end by a bottom portion,and at the other end by a panel support,having an opening,therethrough to provide access to the faceplate panel,. A back electrode,has a potential applied thereto to establish an electrostatic drift field between the back electrode and the photoreceptor,, which is grounded. Triboelectrically-charged, dry-powdered, light emitting phosphor material, having a charge of the same polarity as the potential applied to the back electrode,, is sprayed into the developer tank,, between the back electrode,and the faceplate panel,. The triboelectrically charged phosphor material is directed toward the photoreceptor,on the faceplate panel,by the applied electrostatic drift field. A bias shield,comprising two pairs of insulative shield members,and,disposed around a peripheral sidewall,of the faceplate panel,. At least one conductive strip,is provided on one of the major surfaces of the shield members to repel the triboelectrically charged phosphor material from the panel sidewall,and to influence the deposition of the phosphor material on the photoreceptor, at the edge thereof. A method of developing the latent charge image utilizing the bias shield also is described.