Abstract: This invention relates to enhancing the apparent resolution of electrophotographic printers. This is accomplished by writing a gray of half-tone halo along the periphery of images written on the photoconductor. When the image with its half-tone halo is developed, transferred and fixed by steps in the electrophotographic process, the printed image has a substantially smooth contour. In effect, the gray halo placed around the image merges with the black interior of the image when the image is developed, transferred and fixed. To prevent the image from appearing to be too thick after its contour has been smoothed by the use of the half-tone halo, the number of black picture elements used to write the image on the photoconductor are reduced. Also, the width of image segments making up the image may be adjusted by changing the level of gray used to write the half-tone halo.

Abstract: In the use of a scanned light beam for optical imaging, a random motion modulation is applied to the light beam orthogonally to the scan direction to break up any unscanned or overlapped interstices between adjacent scan lines to make the interstices appear nearly invisible.

Abstract: A system for reproducing the image on a document comprises a scanning system including a galvanometer driven mirror which reflects a collimated image of an illuminated band via a focusing lens system onto a line array of photosensitive elements. Relative movement between the scanning system and the document causes the scan of successive bands across the document, generating signals at the photosensitive elements that represent line image variations. The photosensitive elements are arranged in 1:1 correspondence to individual ones of a line array of ink jet printers disposed adjacent a copy document. Both the signal generating and image reproducing systems scan their associated documents in synchronism so that the image may be reproduced in direct fashion or using interleaving for higher density with given inter-element spacing.

Abstract: A system is disclosed in which a light beam from a light source is scanned over the surface of a document to be copied which is located at a nominal document position within the system. Light from the light beam is retro-scattered by the document, collected by a lens system and focused upon a detector. The intensity of the light impinging upon the detector is indicative of information contained upon the portion of the surface of the document being scanned. The system further includes aperture stops for limiting the solid angle of collection of retro-scattered light from a first position beyond the nominal document position from the lens system to a first predetermined angular value and for limiting the solid angle of collection of retro-scattered light from a second position between the nominal document position and the lens system to a second predetermined angular value.

Abstract: Erase apparatus for use in an electrophotographic copier machine where an array of light-emitting diodes (LEDs) are placed adjacent one end of a light channel with the other end adjacent a moving photoreceptive surface. The channel allows light rays to pass freely from LED to LED but contains the rays in a direction parallel to the direction of photoreceptor movement. The channel may be comprised of sides with reflective surfaces normal to the photoreceptive surface or may be a solid plastic sheet through which the rays pass. In the latter embodiment, rays are internally reflected from the surfaces of the plastic sheet.