Patent · US Expired

Method of compensation for the effects of thermally-induced droplet size variations in ink drop printers

US6213579A · kind A · utility

39Cited by
42References
27Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 24, 1998
Grant dateApr 10, 2001
Priority date
Expiry dateNov 24, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N1/407
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An apparatus and method is provided for compensating for the effects of thermally induced droplet size variations in ink-jet printers. The apparatus includes a temperature determination unit for determining the temperature of the print head, and a halftone adjustment unit configured to receive the print head temperature from the temperature determination unit and to receive image data in the form of nominal halftone values. The adjustment unit can increase or decrease the number of dots to be printed, and thereby compensate for droplet size variations, either by adjusting the nominal halftone values based upon the temperature or by adjusting a threshold array based upon the temperature. The temperature determination unit can predict the print head temperature by counting the number of dots to be printed by counting the binary halftone values fed to the swath memory.

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