| 摘要 |
The invention relates to an illumination correction device for a document scanner comprising an illuminating tube (1) which is of tubular shape and which is intended to illuminate a zone of a document (3) to serve a reader which is provided in the conventional manner in the form of a strip (5) capable of scanning in a single operation at least one rectilinear portion of the illuminated zone. It is composed of a mask, constructed in the form of an alternation of zones, permitting in succession the filtration or non-filtration of the light from the illuminating tube passing towards the read strip, which extends on the tube or on a mirror parallel to the tube and/or to the strip on the tube or on a mirror, the spacing of the zones, on either side of a central zone, in a direction towards the two ends of the mask varying in such a manner that the illumination seen from the strip is maintained at a uniform level for a document of uniform colour. |
