Abstract: Trinary and quaternary halftone reproduction systems for electronic printers in which discrete combinations of either three or four reflectance level pixels having optimum intermediate levels form halftone cells to provide an increased number of gray steps for processing image signals, yielding an optimum Tone Reproduction Curve.

Abstract: A system for self-aligning a raster input scanner in the slow scan direction where, at start of scan, a target having a variable density image is scanned first until a preset target image line is obtained and the position of the scan carriage registered; then from the registered position, the platen is scanned through a predetermined number of scan lines; following this, the carriage is reversed and returned the same number of scan lines where the target is again scanned and the target image line obtained compared with the previous target image line to determined if a valid scan cycle has taken place.

Abstract: A touch input system having a CRT with opposing rows of aligned LED's and photosensors on four printed writing boards forming a frame about the CRT screen and which establishes a grid permitting any spot where the screen is touched to be identified, and flexible circuits electrically and mechanically attaching the boards corner to corner to form the frame. In an alternate embodiment, individual circuit components are used, either alone or in combination with adhesive to mechanically attach the flexible circuits to the boards. In another alternate embodiment, a one piece flexible circuit with underlying supports along each of the four sides of the frame is used in place of the printed wiring boards.

Abstract: Apparatus for priming the magnetic end seals in the developer of a xerographic-based copying or printing machine immediately on startup to quickly establish the seals and prevent initial escape of toner from the developer housing, the apparatus continuing to supply developer material to the end seals while the machine is operating, thereby to prevent seal degradation or loss resulting from use and wear.

Abstract: Feed roll cleaner for cleaning and renewing the frictional surfaces of the paper feed rolls of a reproducing or printing machine having a relatively rigid lightweight rectangular board fittable within the machine paper tray in place of the copy sheets, the board having discrete patches of abrasive material on the surface thereof opposite the feed rolls such that on actuation of the machine, the feed rolls rub against the patch opposite thereto until the machine misfeed detector responds to the failure to feed a sheet and shuts down the machine.

Abstract: A high speed digital ionographic printer employing an ion deposition control bar interposed between the ion source and the movable charge receptor, the bar having n parallel rows of apertures each with a ring-like control electrode, the aperture rows being perpendicular to the direction of movement of the charge receptor, a combination of n line buffers and n shift registers associated with control switches for providing preset negative or positive modulating potentials to the aperture control electrodes in accordance with the image pixel content of the n lines of image signals currently in the shift registers to provide controlled ion flow through the apertures with partial ion deposition on the charge receptor of n lines at once, the block of n image lines being stepped by one each time the charge receptor moves one line.

Abstract: A xerographic copying/printing machine in which the photoreceptor has a row of discrete image marks along one side margin, a CCD type array spaced opposite to and aligned with the row of photoreceptor marks to provide successive blocks of image signals representing the instantaneous pattern of marks viewed by the array on each scan, a light bar spaced opposite the other side of the photoreceptor and aligned with the array for illuminating the array sensors through the marks, and a circuit for converting the image signal output of the array to clock signals representative of photoreceptor speed and position.

Abstract: An electrostatic voltmeter with probe for measuring the charge on a surface, the probe comprising a microdeflector unit having a base; a flexible finger supported on the base in cantilever fashion, the finger deflecting in response to a potential difference thereacross; means to bias the base to a predetermined potential; a sensing electrode on the finger having a side positionable in spaced relation to the surface, the capacitive relation established creating a charge representative of the charge on the surface on the sensing electrode causing deflection of the finger; means to impinge a beam of light on the finger; and a detector disposed to detect reflection of the beam by the finger on predetermined deflection of the finger corresponding to a preset charge measured on the surface.

Abstract: An image sensor array and method of fabrication which facilitates replacement of a defective one in a series of arrays butted together to form a longer scanning array in which a (110) silicon wafer having a row of photosites has separation lines etched thereon by orientation dependent etching along the (111) planes, with the separation lines for the opposite ends of the array each consisting of first and second partial boundary lines longitudinally offset from one another connected by a third boundary line so that the ends of the array have a has a generally L-shaped offset permitting bi-directional separating and aligned inserting movement when replacing a defective array.In a second embodiment, the arrays are formed on (100) silicon with alternating `nail` head and `mesa` head shapes to facilitate removal and replacement of a defective array.

Abstract: A reproduction machine having a duplex tray for processing duplex copies and copy sheet inverter, each with an adjustable back stop for adjusting the duplex tray and inverter size in accordance with the copy size being processed. To enable automatic operation, a control which includes sensors disposed in the path of the copy sheets is provided for measuring the size of the first copy sheet as the copy sheet is being processed and adjusting the duplex tray and inverter back stops in accordance with the size copy sheet determined.

Abstract: A roll supply having a pair of idler belts for supporting a supply roll of sheet material, stationary and movable knife blades, the latter having a V-shaped cutting edge, an eccentric for reciprocating the movable knife blade in one direction into cutting relation with the stationary knife blade, the movable knife blade having projections which rest on the stationary knife blade, a spring biasing the movable knife blade against the stationary knife blade, the movable knife blade being made of spring steel deformed into a slight V-shape relative to the stationary knife blade so that as the movable blade is reciprocated, the movable blade is displaced in a direction substantially normal to the direction of blade movement and a pair of cutting points are established which move together at the center, severing the sheet material, first and second roll pairs for advancing the sheet material to a cutting position, and control for actuating the roll pairs and the eccentric to cut the sheet length selected.

Abstract: A process for forming individual dies having faces that allow the dies to be assembled against other like dies to form one and/or two dimensional scanning arrays wherein the active side of a wafer is etched to form small V-shaped grooves defining the die faces, relatively wide grooves are cut in the inactive side of the wafer opposite each V-shaped groove, and the wafer cut by sawing along the V-shaped grooves, the saw being located so that the side of the saw blade facing the die is aligned with the bottom of the V-shaped groove so that there is retained intact one side of the V-shaped groove to intercept and prevent cracks and chipping caused by sawing from damaging the die active surface and any circuits thereon.

Abstract: Adjustable image print magnification system for a printer of the type using a raster output scanner having a rotating scanning polygon, a pixel clock providing clock signals for clocking pixels from an image signal source to the scanner, a polygon clock for controlling the rotating speed of the polygon, a first cycle stealing circuit for reducing the scanner pixel and polygon clocks together to control image length, and a second cycle stealing circuit for reducing the pixel clock only to control image width.

Abstract: A high speed digital ionographic printer having a rotatable charge receptor, an ion source with ion discharge slot opposite the charge receptor, a cylindrical screen about the ion source composed of a conductive substrate with tiny holes and a photoconductive cover layer, parts of the screen riding against the charge receptor so that the screen rotates at the same velocity as the charge receptor, a screen charge corotron, and a laser writing beam which is scanned line by line across the moving screen to write latent eletrostatic images thereon which thereafter modulate the flow of ions through the slot in accordance with the latent electrostatic image written on the screen.

Abstract: Scan lamp intensity control with reflective patch scanned along with each image line, the reflectance signals obtained being later separated from the image signals and compared to a desired intensity level adjusted to the D/A current reference voltage. To maintain operation within the range of photosite offset adjustment, a scan lamp intensity setpoint is obtained at the beginning of scan.

Abstract: A system for enhancing the use of digitized documents as information transmitting and storage objects in connection with an electronic printer having an image input scanner for scanning documents and converting the image content to image signals. In one embodiment, a bar-coded document has an encoded image representing a secret message, and the printer is equipped with a recognition circuit that uses the bar code to distinguish the encoded document from other non-coded documents to be printed and readies a decoder which upon proper authentication, automatically decodes the encoded image signals output by the array so that the printer provides a print with the decoded message.In a second embodiment, the digitized image comprises an auxiliary software program to be loaded into the printer memory, with a selector circuit for loading the software signals output by the array into the printer memory, with a selector circuit for loading the software signals output by the array into the printer memory.

Abstract: A copier/printer with a light/lens system providing copies of documents, a raster output scanner providing prints in response to image signals, a source of screen image signals, and control means for operating both the light/lens system and the raster output scanner together while accessing the screen image signals so that the raster output scanner creates a dot matrix screen on the photoreceptor over which the latent image of the document being copied is placed by the light/lens system.

Abstract: An adhesive binding tape consisting of a backing portion with temperature activated adhesive on one side, the exterior of the backing having alternating thick and thin sections extending along an axis substantially perpendicular to the longitudinal axis of the tape and forming alternating rows of peaks and valleys of generally rectangular cross section.In a second embodiment, the peaks and valleys have a generally triangular cross section.

Abstract: Process and apparatus for minimizing residual charges in the shift registers of a CCD type scanning array in an asynchronously operated image input terminal in which the unknown arrival time of the next integration signal is predicted and, based on that prediction, the last periodic dumping pulse before the integration signal is delayed a required period of time to assure clearing of residual charges from the shift registers.

Abstract: An electronic reprographics/printing machine with at least one scanning array for converting images on documents to image signals, a document tray for holding a stack of the documents to be scanned, a document transport to bring the documents from the tray to the array for scanning, a controller, an input device such as a keyboard, mouse, touch display, etc. for programming in programming parameters with an associated separator code, a control sheet with a bar code representation of the same separator code for interleaving with the documents for scanning by the array, a bar code discriminator for distinguishing documents with bar codes from documents without bar codes, a bar code reader for reading the bar code to identify the separator code thereon, and a control to match the separator code obtained from the control sheet with the separator code associated with the programming parameters whereby the controller operates the machine in accordance with the program parameters.