Patent · US Expired

Digital image forming apparatus

US5729626A · kind A · utility

10Cited by
11References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 28, 1994
Grant dateMar 17, 1998
Priority date
Expiry dateDec 28, 2014

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N1/40062
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

In a digital image forming apparatus, a document image is read as digital data, and an image type of bi-level image or multi-level image is discriminated from the digital data. For a bi-level image, an intensity of laser beam for exposing a photoconductor is modulated according to the image data with a duty ratio of 100%. On the other hand, for a multi-level image such as a photograph image, the intensity of laser beam is modulated with a duty ratio in the unit of two or more dots according to the image data. The duty ratio and the laser output power are changed according to a type of document image or according to sensitivity characteristic of the photoconductor.

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