Patent · US Expired

Process for recording semihalftone images and device for conversion of image dot tonal value data

US5014138A · kind A · utility

26Cited by

8References

15Claims

0Family size

Assignee

E.I. DU PONT DE NEMOURS AND COMPANY · US

Inventors

Gerhard Fischer · Offenbach, DE
Helmut Quabeck · Babenhausen, DE

Key dates

Filing date	Feb 14, 1990
Grant date	May 7, 1991
Priority date	—
Expiry date	Feb 14, 2010

Classification

Technology area (CPC H)Electricity
CPC primaryH04N1/4051
WIPO fieldAudio-visual technology
WIPO sectorElectrical engineering

Abstract

The invention provides for deciding whether a recording dot is to be printed for the reproduction of scan dots. The scan dots being considered are complied in an input switching network into groups, for which an arithmetic processor determines the tonal value sum. The arithmetic processor emits a signal, if the tonal value sum exceeds a certain figure. The recording dot to be printed is determined by the presence of the signal in an output switching network. This process is performed successively for increasingly larger areas of the original, that is, for increasingly larger quantities of scan dots.

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