GB1407487A - Method and apparatus for producing screened rotary formes - Google Patents

Abstract

1407487 Facsimile system DR-ING RUDOLF HELL GmbH 8 Dec 1972 [9 Dec 1971] 56904/72 Heading H4F A composite page of a newspaper or magazine containing text and pictures is produced as a screened rotary forme by means of an engraving unit or exposing lamp, and to enable the screen dots to be produced continuously as adjacent complete image lines the information derived from the required characters and/or pictorial masters is first stored in one or more first storage devices from which it is extracted and stored in the desired sequence of reproduction in an intermediate storage device or device ready for extraction as complete image lines. These first and intermediate storage devices enables a screen forme on a continuously rotating cylinder to be produced continuously without the preparation of mounting on a scanning cylinder of masters of the required dimensions and in the desired layout plan. The masters are photoelectrically scanned and the resulting analoque values quantized, binary coded and stored as screen dot data relating to complete image lines. Identification data is also produced for each character or picture to be reproduced and stored therewith in the first storage devices. Upon reproduction on to the printing cylinder the data for the page lines of the pages (e.g. three) in a run (e.g. three runs, thus nine pages are reproduced on the cylinder by three engraving units of exposing lamps) and which correspond to a circumferential line of the printing cylinder is successively called up from the intermediate storage device of devices. The same sequence of operations occurs simultaneously for all the runs on the cylinder and is repeated on each revolution of the cylinder. The first storage devices may comprise core stores or drums stores for character data, which data has eight values of density and is stored using threefigure binary numbers, and magnetic tape or disc stores for half-tone picture data which data for example is coded into 64 or 128 graduations. The identification data comprises address and control data. The intermediate storage devices preferably comprise magnetic disc or tape stores.