Abstract: An optical scanner with variable line resolution, said scanner collecting information from an original along lines with a predetermined mutual spacing. A calculating unit calculates the location of lines with desired resolution with respect to the scanned lines in response to a desired resolution. A line detector registers optical information along lines on the original and supplies a signal representing the registered, optical information. The information signal is branched along two branches in a branch means. A delay is coupled in one of said branches and is adapted to delay the information signal passing in the branch for a period of time corresponding to a line length in said information signal. An interpolation means receives the information signals from said branches and forms as a desired line an interpolation signal between information signals in response to the location of the desired line with respect to the location of the scanned lines.

Abstract: A scanner system comprises an optical line detector for linewise, optical scanning of an original for generating a data signal in response to the grey-level received by the detector from points along a respective line. The points are sorted with associated grey-level values in groups in response to their positional origin on the original. The individual threshold values for the grey-level values are determined statistically for a plurality of zones on the original in response to the frequency of respective grey-level values in the respective zone. The threshold values of respective zones are stored in a store. The original is re-entered by linewise, optical scanning, and the data signal generated by the scanning and representing grey-levels in points along respective, entered lines is compared in a comparator with a threshold value calculated for the point concerned, and in response to this a binary, electric representation of the original is generated.