Patent · US Expired

Biasing scheme for improving latitudes in the tri-level xerographic process

US5080988A · kind A · utility

8Cited by
10References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 22, 1989
Grant dateJan 14, 1992
Priority date
Expiry dateNov 22, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G15/0121
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

The operating latitude of the tri-level xerographic process is improved by replacing the standard DC bias that is applied to one or both of the developer housings in conventional tri-level imaging with a chopped DC (CDC) developer bias. Chopped DC biasing is the alternate application of two discrete bias voltages to a developer stucture in a periodic fashion at a given frequency, with the period of each cycle divided up between the two bias levels at a duty cycle of from 5%-10% or 90%-95% depending upon which of the two developer structures is being biased. In the case of the DAD developer structure the duty cycle of higher of the two biases is 5%-10% and in case of a CAD developer structure the duty cycle of higher of the two biases is 90%-95%.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.