Exposure system for electrostatic machines

Claim 1

In a reproduction machine for producing selectively one or more copies of an original, the combination of: a movable photosensitive member; drive means for moving said photosensitive member, means to charge the photosensitive member in preparation for imaging; an exposure station whereat said charged photosensitive member is adapted to be exposed to a light image of the original; a platen for supporting the original; image projecting means forming an optical path for transmitting a light image of the original on the platen to the exposure station and the photosensitive member to form a latent elctrostatic image of the original on said member; relatively low power flash illumination means adapted when triggered to illuminate the platen and the original thereon to form each time said flash illumination means is triggered a light image of said original for transmittal to said exposure station by said image projecting means; optical path displacing means to displace the optical path formed by said image projecting means conjointly with said photosensitive member and in substantial parallelism with said photosensitive member at said exposure station, and control means to trigger said flash illumination means at least twice for each copy of an original to be made and actuate said optical path displacing means to thereby project at least two full frame overlapping exposures of the original onto said photosensitive member, said overlapping exposures together forming said latent electrostatic image of the original.