Freehand image scanning device and method

摘要

A scanning device (10) for forming a scanned electronic image (54) includes an imaging sensor (22) and at least one navigation sensor (24 and 26). The imaging sensor is a linear array of sensor elements, with a two-dimensional navigation sensor array at each end. The scanning device has three degrees of freedom, since position information from the navigation sensors allows manipulation of an image signal from the imaging sensor to reduce distortion artifacts caused by curvilinear scanning. Acceptable sources of the position information include printed matter and contrast variations dictated by variations in the inherent structure-related properties (64) of the medium (14) on which the scanned image is formed. Illumination for optimal operation of the navigation system may be introduced at a grazing angle (30) in some applications or in the normal to a plane of the original in other applications.