Abstract: A cassette web transport mechanism is placed upon an overhead image projector. Multiple overhead projector slides are conveniently secured in a roll of the web. The web is moved in forward or reverse direction by remote control in order to display the desired slide through the projector.

Abstract: The disclosure describes an illumination apparatus for a xeroxgraphic copy machine which produces a copy of an original document. The illumination apparatus comprises a lamp, a shield which surrounds the lamp and has at least one aperture enabling the lamp to illuminate the original document, and at least one filter disposed between the lamp and the document for selectively controlling the intensity or wave length of the light radiated to the document. Preferrably, the illumination apparatus comprises at least two aperatures in the shield and at least two transmissively dissimilar filters, and a control apparatus, such as a control knob, belt and pulley, for selectively disposing the filters between the lamp and the original document.

Abstract: The roller transfer corona is an apparatus which eliminates the problem of image voids which exists when folded or creased paper is used as the copy paper in a xerographic copy machine. The apparatus comprises contact means, such as a coated push roller, for physically engaging and forcing the folded copy paper against the photoconductor element of the copy machine in combination with corona means, such as a corona wire, located adjacent to and separate from the contact means, for effecting the transfer of toner particles from the photoconductor element to the copy paper.