Abstract: An imaging device includes a substantially continuous web of media; a web transport system configured to transport the continuous web along a web path; and a print station positioned along the web path and configured to apply ink to a first side of the continuous web to form images thereon. An image sensor is positioned downstream from the print station along the web path to scan a second side of the continuous web opposite from the first side. The image sensor is configured to generate a reflectance signal indicative of a reflectance of light from the second side of the continuous web. A controller is operably coupled to receive the reflectance signal from the image sensor, and to adjust at least one print process parameter based on the reflectance signal while the imaging device is performing print operations.

Abstract: A method of decreasing toner in solid area development to improve the latitude of a xerographic process in a machine having a projecting system for modulating a beam and projecting an image onto an imaging surface by specifying pixels defining solid image areas and selectively modulating the beam with regard to the specified pixels to change the state of the pixels from black to gray or partial white.

Abstract: A method of maintaining consistent large solid area development by developing a large area test patch covering the image area of a photorececptor and detecting the lead edge and trail edge density of the test patch using a densitometer to measure reflectance. If a density differential between lead and trail edge density is detected, electrostatic parameters such as toner concentration, developer bias, and photoreceptor potential are adjusted to maintain constant large solid area development.

Abstract: A printing machine having an imaging surface, a scanning system for modulating a beam and scanning an image onto the imaging surface, a device to designate a variable relative darkness factor, a store for holding a partial array of the image to be reproduced, a comparator for relating the partial array of the image to be reproduced with standard reference formats to produce correlation signals, modulating logic responsive to the correlation signals and the variable relative darkness factor to provide timing adjustments and a modulator for modulating the beam and scanning the image onto the imaging surface in response to the timing adjustments.

Abstract: A system for compensating for motion errors that degrade image quality by modifying the modulation of a scanning beam across a photosensitive surface in response to changes in speed of the photosensitive surface by use of a shaft encoder mounted adjacent to the photosensitive surface to determine the speed of the photosensitive surface, a comparator electrically connected to the sensor for determining the change of speed of the photosensitive surface in relation to a standard speed, a converter connected to the comparator and responsive to the change in speed to provide a signal representing an image quality factor, and for altering the modulation of the beam of the scanning system in relation to the speed of the photosensitive surface.

Abstract: An apparatus which develops an electrostatic image with marking particles. The apparatus includes a developer roller for transporting the marking particles to a position adjacent an electrostatic image for the purpose of developing the image. During deposition of the marking particles on the image, the apparatus senses the charge thereon and in response to the sensed charge, additional marking particles are dispensed into the developer roll housing for use by the developer roller. The apparatus further includes an impoved method for periodically determining the actual concentration of the marking particles within the developer housing in order to modify the rate at which the marking particles are replenished, thereby maintaining an equilibrium concentration of marking particles within the developer housing.

Abstract: A printer member adapted to be used in an ion printing device having a conductive coating positioned on a portion of the marking head near the charge receiver. The conductive coating is electrically connected to the housing in order to substantially equalize the voltage potential of the housing and marking member. The above arrangement enables the device to be set at a single operating state that would allow the device to operate very near its breakdown threshold at all humidity levels.

Abstract: A device for the adjustment of the digital data stream that drives the modulators in an ionographic printing device. In particular, the device stretches strings of black image pixels to produce wider vertical lines and other fine details that may have been adversely affected due to modulator crosstalk. Moreover, the present invention is implemented in such a manner, so as to enable the end user to selectively define the magnitude of stretching to be applied to the strings of black pixels.

Abstract: A method and device which removes particulates from a gap in an ion projection device, when the device is not enabled for printing, with the gap being defined by a charge receiver and a printer head. The particulates within the gap are subjected to a variety of mechanical forces due to the application of a varying field from a plurality of modulation electrodes and a flow of transport fluid from a pressurized transport fluid source. The forces applied to the particulates cause them to be removed from the above gap thereby enhancing the integrity of the imaging charge which is placed upon the moving charge receiver sheet.

Abstract: Processes for preparing ionographic imaging member including providing a flexible, shrinkable tube containing a dielectric film forming polymer having a T.sub.g of at least about -40.degree. C., charge decay of less than about 2 nonocoulombs per cm.sup.2 per second and elastic memory, providing a cylindrical support member having an outer diameter that is less than the inner diameter of the flexible tube, applying a continuous coating on the interior of the tube or on the exterior of the cylindrical support member, the coating comprising a material selected from the group consisting of an electrically conductive material, an adhesive material and mixture thereof, shrinking the tube to bring the inner surface of the tube and the outer surface of the cylindrical support member into intimate physical contact with the continuous coating. This imaging member may be employed in an ionographic imaging process.

Abstract: This invention is a transfer means in a electrographic printing apparatus having a charge retaining member with a relatively high background potential of a first polarity, a transfer corotron having a relatively high potential of a second polarity and providing a transfer region for a transfer of toner to copy sheets, and a pretransfer baffle disposed adjacent to the transfer corotron, the pretransfer baffle being charged to a potential approximately the same as the charged retaining member and having said first polarity, the pretransfer baffle and the charge retaining member forming a gap for the passage of copy sheets to the transfer region, and the copy sheet being in contact with the charge retaining member before reaching the transfer region.

Abstract: The adjustment of the strobe and data voltages to the array gates that drive each of the modulators in an ionographic printing device, in particular the lowering of the data voltage level below the strobe voltage level for each of the array gates. The lower limit on the data voltage level is the voltage level where the generated ions are not shut off completely at the modulating electrode.