Robert J Thoreson

US Patent:

47309300, Mar 15, 1988

Filed:

Jun 24, 1986

Appl. No.:

6/878046

Inventors:

Robert J. Thoreson - Seattle WA
Steven J. White - Seattle WA

Assignee:

Technical Arts Corporation - Redmond WA

International Classification:

G06K 1100
G06K 712

US Classification:

356407

Abstract:

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.