Curve scanning device with television system - has video signal improvement for steep curve gradients by differential magnification

摘要

A curve or graph reading device for translating a graph on a recording surface (11) into an image on a television screen (15) provides a good quality video signal in the presence of steep curve gradients. An optical system (12, 13) containing a cylindrical lens (12) with its flat surface parallel to the recording surface (11) and its cylinder axis parallel to the ordinate direction presents an image of the curve to a television camera (14) as the recording surface moves in the abscissa direction (a). The camera scans periodically in the ordinate direction. To improve scans periodically in the ordinate direction. To improve the video signal when the curve makes an acute angle to the ordinate direction, the optical system magnifies more strongly in the abscissa direction than in the ordinate direction.