A light pipe information display, having a non-conductive, transparent planar first glass sheet and a non-conductive planar opaque second glass sheet, both sheets being disposed adjacent to one another with their inner surfaces opposing one another in spaced-apart relationship. The second non-conductive sheet has a plurality of discrete transparent light pipes formed therethrough, wherein at least one of said non-conductive sheets includes electrical conductors disposed on its inner surface. The conductors are connected to an electrically responsive display material, such as a liquid crystal or electroluminescent material disposed between the first and second sheets, arranged in discrete character-forming segments. Each segment is aligned with one of said discrete light pipes. There is a third opaque sheet disposed on the exposed surface of the second sheet and includes a plurality of smaller light pipe holes, each hole being aligned with each light pipe window of the second sheet. The third sheet has a concave outer surface to conform to the drum of a standard dry copy photocopy machine. Programmed electrical circuits provide scrolling of the images produced on the display in step with the movement of the drum. The dot segments are staggered in the scrolling direction of the drum, on the surface of the display, so that high resolution, non-segmented images can be produced.

An electrolytic display cell includes two plates, one of which is covered by a semi-transparent electrode. The display is obtained by connecting the electrode to a source of potential of a first polarity and the erasing by connecting the electrode to a source of potential of a second polarity. The electrode has a first terminal and a second terminal. The first and the second terminal are adapted to be connected to apparatus for detecting whether the electrode has been made visible.

A plasma addressed liquid crystal display which includes a pair of spaced substrates upon which orthogonal electrodes are mounted and electro-optical material layer mounted in contact with a first group of electrodes on the first substrate and an ionizable gas between the substrate and the electro-optical material layer to provide a discharge region that functions as a visible display.

A computing system having a non-volatile memory with locations with store data and are physically accessible such that the locations can be human visually readable to determine the data values stored therein. The non-volatile memory is operatively coupled to the computing system so that the computing means can write data into the non-volatile memory. A postage meter employing this system is adapted to be energized by an external source of operating power and includes a postage printing mechanism for printing postage and a computing system coupled to said postage printing mechanism for accounting for postage printed by the printing mechanism. A non-volatile memory for storing data is operatively coupled to the computing system and includes locations for storing data, critical postage accounting and other data when the postage meter is not energized by the external source of operating power. The location are human visually readable to determine the data stored therein and may also be machine readable by the computing system.