Process and arrangement for generating high-quality matrix print using electrophotographic printing equipment

US5767888A · kind A · utility

Assignee

• Oce Printing Systems GmbH · DE

Inventors

• Martin Schleusener · Zorneding, DE
• Volkhard Maess · Erding, DE
• Edward Morris · Erding, DE

Key dates

• Filing date: Aug 10, 1995
• Grant date: Jun 16, 1998
• Expiry date: Aug 10, 2015

Classification

• Technology area (CPC H): Electricity
• CPC primary: H04N1/40087
• WIPO field: Audio-visual technology
• WIPO sector: Electrical engineering

Abstract

An electrophotographic process and arrangement for generates a macro-charge zone inkable by toner applicators and delimited by an inking limit (EG) having an adjustable contour on a photoconductor of a printing or copying machine, using at least one exposure-variable and position-variable controllable light source (LED), such as an LED comb or laser. By controlling the exposure of the light source and its radiation position on the photoconductor and by controlling a bias voltage (UB) which can be applied between photoconductor and toner applicator, an electrostatic potential relief (UR) made up of individual adjacent micro-charge zones (UM) of exposure-dependent size is generated on the photoconductor and the inking limit (EG) is defined, the contour of the inking limit being determined by the bias voltage level (UB) on the potential relief (UR). The process and the arrangement allow an offset-like printing quality to be obtained, both with respect to the generation of half-tone images and of lines and characters.