| 摘要 |
<p>A scanner and scanning method for scanning a sheet such as a chart. The scanner includes scanning means and detection means. The scanning means includes means for supporting and mounting the sheet, and illumination means for directing light onto an illuminated area of the sheet, the illuminated area being elongated along a scan direction. The scanning means also includes means for causing the illuminated area to move across the sheet in a movement direction normal the scan direction. The detection means comprises a photodetector array and a coherent fiber optic bundle. The coherent fiber optic is tapered, such that it has a comparatively wide aperture adjacent the illuminated area, and a comparatively small aperture adjacent the photodetector array. In a related aspect, the illuminated area is caused to move in a first direction across the sheet such that the illumination means sequentially directs light onto a series of pixel areas of the sheet. The color of the light is varied such that as the illuminated area moves across the sheet in the first direction, the color of the light alternates between first, second and third illumination colors, thereby alternately illuminating the pixel areas with the illumination colors. An illumination color signal is produced for each pixel area. The processing means detects light reflected from each pixel area to produce an intensity signal, and color processing means combines the illumination color and intensity signal for each pixel area with the same signals from two adjacent pixel areas, to provide a pixel color signal representing a composite color for the pixel area. Means are provided for processing sequences of pixel color signals to eliminate transition colors.</p> |
