Abstract: A lens system for scanning a document positioned on a flat support. The lens system operates in cooperation with apparatus which scans a beam of illuminating light across the document and a scanning mirror, which directs reflected light from the illuminated document in a direction toward an array of photodetectors. The lens system is positioned between the scanning mirror and the photodetector array and includes a movable doublet lens and fixed doublet lens. The movable doublet lens collimates the light through the lens system, while the fixed doublet lens focuses an image of the scanned document portion upon the face of a photodetector array. A set of 6 correcting lenses are arranged symmetrically with respect to a plane of symmetry in a position between the two doublet lenses. A barrel cam and a follower arrangement is provided for moving the movable doublet lens in synchronism with the image scanning mirror, so that optical field flattening is achieved.

Abstract: A photographic apparatus having a lens movable along an axis for automatically focusing an object to be photographed is disclosed. The apparatus includes a rotatable sleeve controlled by electrical signals produced by photoreceptor means adapted to receive light emitted by the apparatus and reflected from the object. The sleeve effectuates the movement of the lens along an axis to bring the object into focus. The apparatus further includes assembly means, carrying the photoreceptor means, pivotably secured to the sleeve for adjusting the light received by the photoreceptor means by an amount corresponding to the rotation of the sleeve, thereby changing the electrical signals to maintain the object in focus.