Patent · US Expired

Apparatus for forming superimposed images

US4912491A · kind A · utility

62Cited by
4References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 19, 1988
Grant dateMar 27, 1990
Priority date
Expiry dateMay 19, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N2201/04794
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An image forming apparatus for forming superimposed images includes a plurality of image forming devices each for forming a different image and a registration mark, corresponding to the position of the associated image, on an image transferring medium. The registration mark is formed on a transparent part of the medium and is illuminated from below. A detector above the medium detects the position of the shadow of the registration mark for each image and the result of detection is used to adjust the position of at least one image forming device to produce proper registration between the images formed by the respective image forming devices.

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