DUAL REFLECTOR ILLUMINATION SYSTEM
Original Publication Date: 1981-Dec-31
Included in the Prior Art Database: 2004-Apr-03
Xerox Disclosure Journal
An illumination system is shown in Figure 1 which utilizes an illumination source and associated reflector to maximize light directed to a scanning lens in an object plane. The illumination system, indicated generally as 2 illuminates a document 4, moving in an object plane in the indicated direction. This system is commonly referred to as a continuous velocity transport (CVT) system and the absence of a platen permits the close positioning of illumination source and reflectors to the document as described below. An image of each incrementally scanned line is reflected at mirror 6, and projected by lens 10 onto CCD photosensor array 12 located in an imaging plane. The illumination system 2 comprises a linear lamp 14 which can be a fluorescent lamp with a reflective coating 16 on the lamp envelope. The coating is omitted from a poition of the envelope so that a clear longitudinal aperture 18 of approximately 45 is formed. A pair of facetted reflectors 20, 22 are located on either side of exposure zone 24 and serve to optimally direct illumination from lamp 16 onto narrow longitudinal exposure zone 24. Elements 14, 20, 22 are shown in end view and that their lengths extend perpendicular to the plane of the page thereby incrementally illuminating line of information on the document as it passes through the exposure zone.