PHOTOELECTROPHORETIC IMAGING APPARATUS WITH CORRECTION FOR PARALLAX

Apparatus for producing images using a transparent electrode, typically a flat plate, over which, a carriage which carries at least one roller, typically a roller electrode, into contact with the transparent electrode. In some embodiments, two or more rollers may be used, one of which may be an image transfer roller. Imaging suspension applied between a roller electrode and the transparent electrode is exposed to electromagnetic radiation under the influence of an electric field to form an image. The roller is rotatably mounted to the carriage by a detachable yoke mounting assembly which enables the ends of the roller to tilt in a vertical plane. The detachable yoke mounting assembly and thus the roller also pivots about an axis parallel to the transparent electrode and perpendicular to the direction of advancement of the carriage and roller. A force is applied to the yoke mounting assembly to maintain a constant force between the roller and the transparent electrode irrespective of any irregularities in contact between the roller and the transparent electrode. Machine drive mechanism is used for propelling the carriage which carries at least one roller over the transparent electrode and also to propel at least one slit aperture plate under the transparent electrode. The carriage and roller are propelled at a greater rate of velocity than the velocity of the slit aperture plate to correct for parallax.