Write white printing system with multi-centered halftone screen

摘要

A set of halftone screens and a write white xerographic system are used for generating halftone images with a minumum of artifacts. The screens used in a four color printer have at least 64 pixels per pattern and are distributed to create four-centered dots that are at either -14, 0, + 14 or +45 degrees (Figs.11,12,9 and 13). The xerographic process involves charging the photoreceptor (Fig.14A), partially discharging the photoreceptor with a scanning beam to create an image (Fig.14B), and then using toner which adheres to the charged portions of the photoreceptor to create the hard copy (Figs.14C,14D).