Array scanning techniques

The objective of this study was to determine the feasibility of scanning cartographic documents by large, semiconductor linear arrays and by specially shaped geometric arrays. The Calspan flatbed image scanner with its linear array sensor was used with supporting computer software to scan and process small sections of the USAF's Cartographic Test Standard (mylar version). The basic properties of the monolithic linear array of silicon photodiodes for the generation of imagery were studied by directly examining the imagery output of the scanner. Two geometric arrays were studied by simulating their aperture geometries with software in a PDP-9 computer. Analysis of the imagery output of the flatbed scanner showed that the linear array produced excellent imagery. Examination of the behavior of the two simulated geometric arrays showed that the line directions found were the ones desired in most cases. Solid state photosensor technology was evaluated. Methods were presented for hardware implementation of geometric array processing algorithms. It was concluded that current array sensing technology is suitable for digitally encoding cartographic documents.