Patent · US Expired

Driving method and apparatus for optical printer with liquid-crystal switching element

US4591886A · kind A · utility

34Cited by
2References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 9, 1984
Grant dateMay 27, 1986
Priority date
Expiry dateJul 9, 2004

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06K15/1252
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A driving method for an optical printer and an optical printer having a liquid-crystal light switching element including a ferroelectric liquid crystal sandwiched between a pair of plates provided with electrodes on adjacent surfaces thereof. The liquid-crystal light switching element is disposed between a light source and a movable photosensitive surface and controlled so as to at least one of transmit and block light from the light source to the photosensitive surface for enabling a printing operation. Voltages v.sub.1 and v.sub.2 are applied to the liquid-crystal switching element substantially in accordance with the equation ##EQU1## and the intensity of light from the light source incident on the liquid-crystal switching element is controlled so that incident light intensity during a period T.sub.2 is weaker than the incident light intensity during a period T.sub.1, where t.sub.0, t.sub.1, t.sub.2 and t.sub.3 represents times, T.sub.1 (=t.sub.1 -t.sub.0) is the period during which a printing operation is effected, T.sub.2 (=t.sub.3 -t.sub.2) is the period during which the photosensitive surface moves, v.sub.1 is the voltage which is applied to the liquid-crystal switching elem…

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