| 摘要 |
<p>ILLUMINATION SYSTEM A system is provided for the sensing of documents, which system includes an arrangement of reflective elements capable of directing illumination onto the object to be sensed in such a manner that the flux density of the illumination is greater adjacent to the boundaries of said object than in the middle portion thereof. This compensates for the vignetting effect found in lenses. A source of illumination is positioned on a first focal line of a cylindrical elliptical mirror, with the object to be illuminated being positioned at the second focal line. First additional mirrors forming end pieces for the elliptical mirror, and second additional mirrors located adjacent to the boundaries of the object to be sensed, cooperate to direct light from the source to the object in such a way as to achieve the desired distribution of illumination across the object. Several different embodiments of the cylindrical elliptical mirror are disclosed.</p> |
