Optical character reader

摘要

An optical character reader comprises a pre-scanner and a main scanner. The pre-scanner coarsely scans the surface of a postal item and generates video signals representing a postal item pattern. The pattern is divided into a plurality of blocks. Of these blocks, a destination address block, for example, is selected. The coordinates of the lower side of the destination address block are determined. According to the coordinates a limited area of the destination address block is determined, which is to be scanned by the main scanner. The main scanner scans finely the limited area and generates high resolution video signals. According to the high resolution video signals a postal code in the destination address block is detected and recognized.