Development of wide area scanner for OCR flat sorter

Recently the demand for flat mail sorting by OCR(Optical Character Reader) has been growing rapidly. Flat mail items are large, and have a variety of thickness. Therefore highperformance scanners which have both wide field of view and deep depth of field are required for flat mail sorting automatiza tion. Furthermore a non-contact type image scanner is needed because flat m ail has a variety of shapes. The authors have developed a prototype wide-ar ea scanner of non-contact type which has 50mm depth of field and twice as w ide field of view as that of conventional letter scanners. As a result of e valuations, expected capability of capturing clear image was confirmed.