Patent · US Expired

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

US5241358A · kind A · utility

4Cited by
6References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 7, 1991
Grant dateAug 31, 1993
Priority date
Expiry dateOct 7, 2011

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 strucrute 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 the 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.