Document illumination apparatus

Claim 1

An illumination apparatus for illuminating a document on a transparent platen comprising, in combination: first and second fixed light sources disposed symmetrically with respect to said platen each light source comprising a lamp and a curved reflector, each curved reflector having an elliptical cross section and the respective lamp being disposed at a focus of the elliptical cross section; first and second rotatable reflectors for reflecting light from the first and second light sources respectively onto the document, the first and second rotatable reflectors being disposed symmetrically with respect to said platen and external of the limits of reflected light from the document, opposite foci of the curved reflectors of the first and second light sources being disposed between the first and second reflectors and the document respectively, light radiated from the first light source to the first rotatable reflectors intersecting light radiated from the second light source to the second rotatable reflector; drive means for interlockingly rotating the first and second rotatable reflectors so that light is reflected therefrom onto the document in superimposed relation at all positions of the first and second rotatable reflectors; and first and second fixed auxiliary reflectors for reflecting light from the first and second light sources respectively onto the document being disposed symmetrically with respect to said platen.