Optical character generator for an electro photographic printer

US5488404A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Friedrich Fleck · Munich, DE
• Klaus Jorgens · Wuppertal, DE

Key dates

• Filing date: May 23, 1994
• Grant date: Jan 30, 1996
• Expiry date: May 23, 2014

Classification

• Technology area (CPC G): Physics
• CPC primary: G06K15/1247
• WIPO field: Computer technology
• WIPO sector: Electrical engineering

Abstract

A plurality of light-emitting diode chips (2) densely packed in the form of rows is associated with driver chips (34) and associated drive chips (3) on both sides. The printing information is supplied from a printer control (6) via a bus system (4, 4' and 5, 5'). Each light-emitting diode chip is subdivided into n groups of light-emitting diodes (for example LED1, LED3, LED5 . . . LED31 and LED98, LED100 . . . LED128), which are arranged geometrically offset with respect to one another transversely to the main direction of the diode row. Each drive chip contains a switching unit (32) for generating internal sequence control signals (for example SWE1, SWE2, I-CLK) and n part-circuits (33/0 to 33/3) associated with the n groups of light-emitting diodes for the simultaneous processing of the printing information into temporally staggered drive signals (DS). Thus, the respective light-emitting diode groups are activated with a temporal offset depending on the geometric offset in order to generate a printed image line which is assembled section by section.