Abstract: A three-dimensional object printer ejects drops of a build material from a plurality of ejectors in a first printhead to form an object on a first region of a member and ejects drops of a support material from a plurality of ejectors in a second printhead to support the object on the first region of the member. The second printhead ejects drops of the support material onto a second region of the member that is separate from the first region to form a substrate layer. The first printhead ejects drops of the build material onto the substrate layer to form a printed test pattern. An image sensor generates image data of the printed test pattern to identify an inoperable ejector in the first printhead.

Abstract: A printer uses closed loop control to keep material drops ejected by a printhead within a predetermined range. The printer forms at least two objects on a support member and then operates a specular sensor array to obtain image data of the two objects on the support member. The two objects have different predetermined heights to enable a controller in the printer to identify the mass or volume of the material drops forming the objects to adjust operational parameters of the printer to maintain the mass or volume of the material drops in the predetermined range.

Abstract: A printer compensates for printing errors occurring during production of the layers for the formation of an object in a three-dimensional printer. The printer includes an optical sensor that generates data corresponding to edges of each layer of the object after each layer is printed. Differences between the raster data used to eject the material to form a layer and the data received from the optical sensor are used to modify the raster data that operates a printhead to form a next layer in the object.

Abstract: A three-dimensional object printer ejects drops of a build material from a plurality of ejectors in a first printhead to form an object on a first region of a member and ejects drops of a support material from a plurality of ejectors in a second printhead to support the object on the first region of the member. The second printhead ejects drops of the support material onto a second region of the member that is separate from the first region to form a substrate layer. The first printhead ejects drops of the build material onto the substrate layer to form a printed test pattern. An image sensor generates image data of the printed test pattern to identify an inoperable ejector in the first printhead.

Abstract: A printer compensates for printing errors occurring during production of the layers for the formation of an object in a three-dimensional printer. The printer includes an optical sensor that generates data corresponding to edges of each layer of the object after each layer is printed. Differences between the raster data used to eject the material to form a layer and the data received from the optical sensor are used to modify the raster data that operates a printhead to form a next layer in the object.

Abstract: A printer uses closed loop control to keep material drops ejected by a printhead within a predetermined range. The printer forms at least two objects on a support member and then operates a specular sensor array to obtain image data of the two objects on the support member. The two objects have different predetermined heights to enable a controller in the printer to identify the mass or volume of the material drops forming the objects to adjust operational parameters of the printer to maintain the mass or volume of the material drops in the predetermined range.

Abstract: Disclosed are an apparatus, optical scanning device, and a corresponding method of forming images on a photosensitive surface. The apparatus includes a laser raster output scanner (ROS) including laser emitters arranged to simultaneously scan a plurality of laser beams across a single scan line of the photosensitive surface in response to received image data corresponding to pixels in an image to be reproduced, and a controller individually controlling each of the laser emitters to selectively apply one of a plurality of power levels to each of the laser beams based on the image data for each of the pixels, wherein a total power applied by the laser beams for each pixel is determined by a sum of the power levels applied by each of the laser beams.

Abstract: A method and apparatus for correcting banding defects in a photoreceptor image forming apparatus. The method or apparatus may form one or more images using one or more laser beams to alter an electrostatic charge on a photoreceptor, check the one or more images for one or more sets of image perfections arising from electric field attenuation in the photoreceptor, and compensate for the electric field attenuation. The method or apparatus may further form a compensated image.

Abstract: A method of printing using an image-on-image device that includes a photoreceptor, including monochrome exposing the photoreceptor or monochrome charging the photoreceptor, wherein monochrome exposing the photoreceptor includes charging the photoreceptor, successively exposing the photoreceptor in a monochrome mode using a plurality of exposing devices during a single revolution of the photoreceptor relative to the exposing devices, and developing a monochrome image on the photoreceptor; and monochrome charging the photoreceptor includes successively charging the photoreceptor via a plurality of charging devices during a single revolution of the photoreceptor relative to the charging devices, exposing the photoreceptor using an exposing device, and developing an image on the photoreceptor. A marking device capable of implementing the method of printing.

Abstract: A method and apparatus for correcting banding defects in a photoreceptor image forming apparatus. The method or apparatus may form one or more images using one or more laser beams to alter an electrostatic charge on a photoreceptor, check the one or more images for one or more sets of image perfections arising from electric field attenuation in the photoreceptor, and compensate for the electric field attenuation. The method or apparatus may further form a compensated image.

Abstract: Disclosed are an apparatus, optical scanning device, and a corresponding method of forming images on a photosensitive surface. The apparatus includes a laser raster output scanner (ROS) including laser emitters arranged to simultaneously scan a plurality of laser beams across a single scan line of the photosensitive surface in response to received image data corresponding to pixels in an image to be reproduced, and a controller individually controlling each of the laser emitters to selectively apply one of a plurality of power levels to each of the laser beams based on the image data for each of the pixels, wherein a total power applied by the laser beams for each pixel is determined by a sum of the power levels applied by each of the laser beams.

Abstract: A method of printing using an image-on-image device that includes a photoreceptor, including monochrome exposing the photoreceptor or monochrome charging the photoreceptor, wherein monochrome exposing the photoreceptor includes charging the photoreceptor, successively exposing the photoreceptor in a monochrome mode using a plurality of exposing devices during a single revolution of the photoreceptor relative to the exposing devices, and developing a monochrome image on the photoreceptor; and monochrome charging the photoreceptor includes successively charging the photoreceptor via a plurality of charging devices during a single revolution of the photoreceptor relative to the charging devices, exposing the photoreceptor using an exposing device, and developing an image on the photoreceptor. A marking device capable of implementing the method of printing.

Abstract: A heating device for desensitizing migration imaging film on an external imaging member scanner. The heating device is curved and has a large surface area to provide maximum heating efficiency. The heating device is mounted to a bracket connected to a scanner cartridge and moves integrally with the scanner cartridge in the direction of the longitudinal axis of the imaging member. The heating device heats the migration imaging film to a temperature to ensure that the surface charge on the film is changed, but is less than a temperature needed for selenium particle migration. As a result, the selenium in the migration imaging film is no longer sensitive under daylight conditions. Thus, the migration imaging film can be removed and heated under daylight conditions providing a significant advantage over film that must be removed and heated under red light conditions.

Abstract: Methods and techniques of electrically biasing and providing a ground for migration imaging members are disclosed. An electrically conductive contact is fixed to the migration imaging member, the electrically conductive contact connecting at least an electrically conductive layer of the migration imaging member to a ground to insure proper imaging. The contacts are fixed to the migration imaging member without having to remove a portion of the softenable layer along its edge to expose the electrically conductive layer of the migration imaging member as is the current practice.

Abstract: An apparatus and method of developing a heat developing film includes a film support surface for supporting and constraining a film and heaters for developing the film supported on the film constraining surface. The film constraining surface may either be stationary or form part of a film transport. The film transport may either be a continuous film transport or a reciprocating film transport. The continuous film transport may be inclined or include an input pinch roller. In addition, the heaters may either be stationary, reciprocatable, or pivotable. The heat is applied by conduction and may include a profiled heater output to control uniformity of the temperature. The apparatus may be provided as a stand-alone unit or may be coupled, either externally to or within, a film exposure device.

Abstract: An apparatus and process for transporting a migration imaging member over a heat source with minimum stress when developing the migration imaging member. The imaging member is conveyed by pinch transport rollers on either side of the heat source, at least one of the pinch rollers being tapered so that the migration imaging member is only constrained along its two edges. The migration imaging member has the degrees of freedom, in its center, to deform under heat and to settle to its stress free state under the pinch. Also, the heat source does not have to be insulated from the transport rollers since the temperature at the transport rollers is less critical due to the minimized tension in the migration imaging member between the rollers.

Abstract: An apparatus and technique to guide a fabric conveyor belt by alignment of the fabric weaves with a mating fabric on a vacuum platen is described. The technique functions in a manner similar to an edge guide, however the correcting forces are applied over the surface of the belt as opposed to the edge of the belt. Robust tracking can be achieved and the need for frequent adjustments of the conveyor rollers by the user is eliminated.

Abstract: An apparatus and method of developing a heat developing film includes a film support surface for supporting and constraining a film and heaters for developing the film supported on the film constraining surface. The film constraining surface may either be stationary or form part of a film transport. The film transport may either be a continuous film transport or a reciprocating film transport. The continuous film transport may be inclined or include an input pinch roller. In addition, the heaters may either be stationary, reciprocatable, or pivotable. The heaters are radiant heaters which may include a profiled heater output to control uniformity of the temperature. The apparatus may be provided as a stand-alone unit or may be coupled, either externally to or within, a film exposure device.

Abstract: An apparatus and method of developing a heat developing film includes a film support surface for supporting a film and heaters for developing the film supported on the film support surface. The film support surface may either be stationary or form part of a film transport. The film transport may either be a continuous film transport or a reciprocating film transport. The continuous film transport may be inclined or include an input pinch roller. In addition, the heaters may either be stationary, reciprocatable, or pivotable. The heaters are radiant heaters which may include a profiled heater output to control distortion of the film. The apparatus may be provided as a stand-alone unit or may be coupled, either externally to or within, a film exposure device.

Abstract: A registration pin for a rotating drum recorder device cooperates with a film to register and support the film during loading the film onto the drum. The registration pin has a reduced profile to reduce the overall size of the drum. The pin also has a construction to permit loading of different types of films onto the drum. The head of the registration pin is provided with a profile that supports and positions the film on the drum, even though the registration pin is shorter than conventional pins. The registration pin includes at least one protrusion to sandwich the film against the surface of the drum. The protrusion may take any appropriate form. The protrusion may include a "teardrop" shaped form, in order to positively hold the film on the drum.