Abstract: A thermal printers and printing methods are provided. The thermal printer has a first thermal print head adapted to pressure a first donor web against the receiver medium and to selectively transfer donor material to the receiver medium in an image wise fashion to form a first image in an image receiving area of the receiver medium; and a second thermal print head adapted to pressure a second donor web against the receiver medium and to selectively transfer second donor material to the receiver medium in an image wise fashion to form a second image in the image receiving area. A receiver medium transport system moves receiver medium along a printing path and the first thermal print head and the second thermal print head are positioned along the path so that they can apply donor material to the receiver medium at least in part simultaneously when instructed by a controller.

Abstract: A receiver medium transport system for a thermal printer, a method for operating a receiver medium transport system and a thermal printer are provided that enable the recording of at least a portion of a second superimposed image on a second receiver medium during the recording of a first superimposed image on a first receiver medium.

Abstract: A method and apparatus of producing images on a series of master plates that are suitable for use as printing plates for the reproduction of multiple copies of composite images from said plates. The master plates are supported with a predetermined alignment relative to each other before mounting on a printing press. Counterpart raster lines of images on the master plates are recorded simultaneously or substantially simultaneously using preferably an ink jet printer so that the counterpart raster lines are printed in alignment.

Abstract: A method and apparatus of producing images on a series of master plates that are suitable for use as printing plates for the reproduction of multiple copies of composite images from said plates. The master plates are supported with a predetermined alignment relative to each other before mounting on a printing press. Counterpart raster lines of images on the master plates are recorded simultaneously or substantially simultaneously using preferably an ink jet printer so that the counterpart raster lines are printed in alignment.

Abstract: A digital projector that has closed loop three color alignment comprising a light source where an optical engine (50) splits a beam of light from the light source into first, second, and third wavelength bands. A first, second, and third spatial light modulator (11, 12, 16) imparts image data and first, second, and third fiducial data respectively to the first, second, and third wavelength bands. The first, second, and third wavelength bands are directed to the first, second, and third spatial light modulator (11, 12, 16), respectively. A combiner combines the modulated first, second, and third wavelength bands. A diverter (19) diverts a portion of the combined modulated wavelength bands to at least one sensor. The sensor (21) then senses a relative position of the fiducials and sends the position information to a microprocessor. The microprocessor then determines an error based on the relative position of the fiducials.

Abstract: A digital projector that has closed loop three color alignment comprising a light source where an optical engine (50) splits a beam of light from the light source into first, second, and third wavelength bands. A first, second, and third spatial light modulator (11, 12, 16) imparts image data and first, second, and third fiducial data respectively to the first, second, and third wavelength bands. The first, second, and third wavelength bands are directed to the first, second, and third spatial light modulator (11, 12, 16), respectively. A combiner combines the modulated first, second, and third wavelength bands. A diverter (19) diverts a portion of the combined modulated wavelength bands to at least one sensor. The sensor (21) then senses a relative position of the fiducials and sends the position information to a microprocessor. The microprocessor then determines an error based on the relative position of the fiducials.

Abstract: An image display device, including: a luminous display having a light emitting face for providing a luminous image; and a reflective image in a screen pattern located on the light emitting face, whereby when the luminous display is emitting light, the luminous image dominates, and when the luminous display is not emitting light the reflective image dominates.

Abstract: An image display device, including: a luminous display having a light emitting face for providing a luminous image; and a reflective image in a screen pattern located on the light emitting face, whereby when the luminous display is emitting light, the luminous image dominates, and when the luminous display is not emitting light the reflective image dominates.

Abstract: An inkjet printer, and method of assembling the printer, for printing an image on a first receiver of a first size and on a second receiver of a second size. According to a preferred embodiment of the invention, the first receiver is fed in a first direction and the second receiver is fed in a second direction orthogonal to the first direction. The printer includes an ink jet print head movable in the first direction to print the image on the first receiver in one printing pass and movable to-and-fro in the first direction for printing the image on the second receiver in at least one printing swath. Thus, printing on differently sized receivers is obtained without reorienting the receivers or changing-out the print head to a different size print head.

Abstract: A binary pagewidth printhead without substantial grayscale capability includes an array of adjacent printhead segments that are distributed across the pagewidth printhead so that adjacent segments overlap at their ends by a predetermined distance. A plurality of printing pixels extending along each segment have physical differences that effect substantially non-uniform transfer functions that decrease toward the ends of segments over the overlap distance. The physical characteristics of the printing pixels are such the their transfer functions vary linearly over the overlap distance. The physical characteristics of the printing pixels may be such the their transfer functions increase monotonically from a small value at the ends of the printhead segments to a larger value away from the ends of the printhead segments. The physical characteristics of the printing pixels in a central portion of each segment are preferably uniform such the their transfer functions are constant over the central portions.

Abstract: Thermal resistive printing apparatus for printing a fluorescent postal stamp image on a receiver in response to a digital image includes a donor web carrying at least one visible colorant material under visible light and an invisible fluorescent material which when illuminated by light in a predetermined portion of a spectrum, emits light in a different portion of the spectrum and a receiver for receiving colorant material and fluorescent material from the donor web and the receiver having a plurality of receiver portions in which the stamp images are to be formed. The apparatus further includes a thermal resistive head including a plurality of thermal resistive elements responsive to the digital image for selectively applying heat to the donor web so that colorant material and fluorescent material are transferred from the donor web to the plurality of portions on the receiver to form fluorescent postal images.

Abstract: A transfer apparatus includes a transfer member, for example, a transfer drum with a line of small closely spaced laser drilled vacuum holes to hold a receiving sheet to the drum surface. The transfer drum is formed by forming a layer of at least intermediate conductivity material on the surface of a core, forming at least one vacuum opening in the core and laser drilling in the layer a line of closely spaced small holes communicating with the opening. In one embodiment, a short focal length lens focuses a laser beam near the surface of the layer, which beam spreads below the surface to form a conical hole. The conical hole helps maintain the continuity of a transfer field while being free from clogging.

Abstract: Toner images are transferred in registry to a receiving sheet held on a transfer drum which drum has one or more layers which varies in resistivity. To offset difficulties in initial securing of the sheet to the drum, a transfer field is not applied as the leading edge of the sheet attaches to the drum. The transfer field is applied after a predetermined delay, which delay is varied as a function of the resistance of the drum.

Abstract: A transmission densitometer determines the optical density of an electrically charged layer of toner material on a photoconductive layer by exposing the photoconductive layer to radiation through the toner layer such that the amount of exposure is characteristic of the density of the toner layer. The change in voltage on the surface of the toner layer caused by the exposure is detected, such that the change in detected voltage is characteristic of the density of the toner layer.The measurement of the change in the detected voltage is carried out by measuring the characteristic voltage on a toner layer developed upon a photoconductive layer using a first electrostatic voltmeter, discharging the characteristic voltage on the area of the photoconductor which was measured by the first electrostatic voltmeter using the exposing device, and measuring the remaining voltage in that area by using a second electrostatic voltmeter.

Abstract: A transfer apparatus includes a transfer member, for example, a transfer drum with a line of small closely spaced laser drilled vacuum holes to hold a receiving sheet to the drum surface. To maintain the continuity of a transfer field but be free from clogging, the holes are narrow near the surface of the drum but wider as they extend deeper in the drum.Conical holes are drilled in the drum by a laser. In one embodiment, a short focal length lens focuses a laser bear near the surface of the drum which beam spreads below the surface to form a conical hole.

Abstract: A power supply system for transfer rollers associated with electrostatographic marking engines. The power supply system includes a power source having a fixed and constant output parameter, such as current or voltage. Additional resistance is connected to the output of the power source to provide the most desirable bias level on the transfer roller under actual operting and material conditions. With a constant current source, a resistance is connected in parallel with the load impedance of the roller system. With a constant voltage source, the resistance is connected in series between the voltage source and the roller system.

Abstract: A transfer member, for example, a transfer drum utilizes a vacuum applied through vacuum holes to the drum surface for holding a receiving sheet. A toner image is transferred to the sheet under the urging of an electric field. To prevent non-transfer over the vacuum holes, the holes are filled or covered with a conductive material that is sufficiently conductive to maintain the electric field over the holes and sufficiently porous to maintain the vacuum at the surface. For example, a polyurethane foam material can be used for the material in or over the vacuum holes.

Abstract: Apparatus for transferring a toner image to a receiving sheet includes a transfer member with vacuum holes. To enhance the continuity of the transfer electric field, a conductive screen is placed on top of the vacuum holes. According to a preferred embodiment, the screen is conductive across the path of the receiving sheet, but insulative parallel to such path.

Abstract: Roller transfer apparatus of simplified construction which has an extended transfer nip exhibiting low pressure for effecting efficient transfer of marking particle images from a dielectric support with a substantial reduction in image transfer defects. In such transfer apparatus, the dielectric support in the form of a web is supported by a mechanisnm offset relative to the transfer roller in an upstream and/or downstream direction to position the web relative to the transfer roller to establish an extended contact nip zone with a low nip pressure. As an example, the support mechanism includes a pair of spaced rollers respectively offset relative to the transfer roller in an upstream and downstream direction to provide a nip zone with a dimension of at least 0.01 m measured in the direction of roller rotation and a nip pressure in such zone of less than 2.times.10.sup.4 Pa.

Abstract: An electrographic reproduction apparatus, of the single-pass type, capable of producing simplex or duplex copies on a receiver sheet traveling in a continuous direction along a path. The reproduction apparatus comprises a first dielectric member movable along a first path, a portion of such first path being tangent to and on one side of the sheet travel path. Transferable images, corresponding to information to be reproduced, are sequentially formed on such first member. A second member is movable along a second path. One portion of such second path is tangent to the sheet travel path on the opposite side from the first path; and another portion of the second path, spaced from such one portion, is located to position the second member in image transfer relation to the first dielectric member.