Abstract: A flash exposure optical imaging system is provided which includes a light housing having a movable top and bottom surface. The top surface contains a document platen, the bottom surface a fixed, wide-angle projection lens. These surfaces are vertically translated past a fixed, central housing wall to vary the system conjugate in response to changes in magnification. In a preferred embodiment, a pair of football shaped cams are rotated in response to position signals from a controller initiated by a magnification change. A pair of T-bars and linkage mechanisms are associated with these cams and their motion provides simultaneous vertical motions to the top and bottom housing surfaces, respectively. During the vertical excursion of the floor assembly, an additional horizontal motion is imparted to the lens so as to maintain correct corner registration of the document at the image plane.

Abstract: The document registration system disclosed is incorporated in a full-frame illumination and imaging system for a photocopier capable of copying at magnification ranging from 1.0.times. through 0.647.times.. The registration system combines a non-linear movement of the projection lens in conjunction with the vertical translation of a document platen to maintain proper lens position and document corner registration throughout the magnification range.

Abstract: An optical system for scanning a document in an object plane includes a pivoting mirror and a projection lens which projects an image onto the surface of a photoreceptor. By rotating and translating the projection lens while simultaneously moving an aperture slit in a direction of movement opposite to the movement of the photoreceptor, a condition is constantly maintained wherein the object plane, lens plane and image plane are maintained parallel thereby eliminating field tilt. With this configuration, the image is also precessed onto the photoreceptor providing a precession distance which can be used to relax constraints normally imposed by scan return conditions. In a specific embodiment, a double reflector arrangement on the image side of the projection lens is used to maintain total system conjugate.

Abstract: An optical system in which a movable photosensitive member is exposed to a light image of an original document. The optical system includes a light source which illuminates a screen having at least two adjacent spaced rows of opaque dots. Movement of the photosensitive member controls activation of the light source. The light source is activated periodically and responds to the photosensitive member moving a distance corresponding to the distance between adjacent rows of opaque dots on the screen.