Browse Prior Art Database

Original Publication Date: 1984-Jun-30
Included in the Prior Art Database: 2004-Apr-04

Publishing Venue

Xerox Disclosure Journal


Figure 1 illustrates, in end view, a portion of an optical illumination system in which a document 10 lying on a platen 12 is illuminated by a lamp assembly 14. Assembly 14 comprises a linear-segmented tungsten lamp 16, used in conjunction with an elliptically shaped reflector 18. The tungsten lamp produces an illumin-ation profile at the platen with significant axial non-uniformities. To improve the profile uniformity, a transparent, heat absorbing substrate 20, is placed across the aperture of assembly 14 and a series of blockers 22 are positioned along the axial length of the substrate. The density and position of each blocker element is determined so as to smooth out the irregular illumination profile.