High-Speed Input Unit of an Automatic Reader

摘要

An input unit for automatic reading machines, capable of operating at speeds of 600-1200 symbols/sec from printed texts, is described. The unit is based on a scanning system of the scanning-spot type. A spot raster generated by the scanning generator is projected on the document being processed. Reflected light from the document is received by six photomultiplier tubes, and the resulting signal is fed to the video processing circuit. The output video signal, coded into discrete levels, is then fed to the memory circuit for further processing.