Precession scanning apparatus.

摘要

A scanning apparatus wherein the illumination scanning means (32) employed travels at a rate which is greater than that of a flat photoreceptor (42) moving in the same direction. In one embodiment, a dual rate mirror assembly (34, 38) scans a document (30) on a platen at a first rate which is greater than the process speed set for a photoreceptor belt. The image is projected through a lens (4U) and precessed by a mirror arrangement (41) along the belt surface in a direction opposite to the belt travel. The precession rate can be set relative to the scanning flyback time, so as to reduce or eliminate an interdocument gap on the photoreceptor and to lower process speeds for a given copy rate.