OPTOELECTRONIC SCANNING PROCESS AND DEVICE

摘要

The invention pertains to a process and device for the optoelectronic scanning of originals. An original (4) is scanned by pixels and lines with the aid of a photodiode line (7). The picture signal values thus obtained for the individual pixels of the scanned lines are read from the integrated shift register (11) of the photodiode-line (7) and fed sequentially to an analogue-digital converter (17). The analogue-digital converter (17) converts only a proportion of the picture signal values from the original (4) to digital picture values for further processing; that proportion is defined by an original extract whose size and shape can be selected. To increase the scanning speed, the picture signal values which are to be converted to digital picture values are read from the shift register (11) at a speed which corresponds to the permissible operating speed of the analogue-digital converter (17) and fed to the latter. Those picture signal values not subject to conversion to digital picture values are read from the shift register (11) at a considerably higher speed.