Abstract: A system for generating a set of bit masks arrays is provided (350-0 to 350-255) where the bit mask arrays (350-0 to 350-255) are such that clusters of entries of different types are spread across each array and entries of different types within the arrays are either part of a larger cluster of entries of that type or are immediately adjacent to a cluster of entries of that type. When a multi-level image (200) is converted to a half-tone image (300) utilizing the bit mask arrays (350-0 to 350-255) a half-tone image (300) which limits the occurrence of small isolated printed or unprinted areas is generated. The bit mask arrays (350-0 to 350-255) are therefore particularly suitable for use with laser printers (28,32) which have difficulty rendering half tone images which comprise small isolated printed and unprinted areas.

Abstract: The present invention enables helical scanning of an image and results in a rectangular image, centered on the imaging media with its boundaries parallel to the media edges and/or to the gripper line.

Abstract: A microfilm reader-printer has a reservoir for copy sheets located near the top of a housing and when a permanent copy of an image projected on a screen (via a lens and a mirror) is required, a sheet is manually removed from the reservoir and fed to the input of a charging station. The sheet is mechanically fed through the charging station to drop by gravity into an exposure station for exposure with the image. Following exposure, the sheet makes a second gravity-induced drop into the nip of a roller pair forming the inlet of a development station. The sheet is fed through the development station, and then the printed sheet exits from an opening below a viewing window.

Abstract: An exposure station of an electrophotographic printer (e.g. a reader-printer) comprises means defining a downwardly inclined support for a copy sheet and stop means for the sheet adjacent to the lower extremity of the support, the stop means being movable between operative and inoperative positions, in the former of which it supports the copy sheet against sliding down the support. The stop means comprises a lower stop means and an upper stop means, the lower stop means being effective in a transverse central region of the support and the upper stop means being in two parts, one lying on each side of said central region.

Abstract: The invention relates to a sheet feeding station for a magazine in which a plurality of individual sheets are located one against another, with a pneumatic pick-up roller rotatably mounted adjacent to the magazine and at that end of the magazine from which the sheets are destined to leave the magazine. The invention is characterized in that the roller is stationary in a precisely defined rest position at the start of a sheet-feeding feeding operation and remains in this rest position until it is sensed that a sheet is held against it by air pressure, the roller then rotating to feed the sheet so held, and continuing to rotate until the sheet-feeding operation has been completed.