Abstract: A method and system for carrying out an image-to-paper printer registration setup includes: using a printer undergoing registration setup, printing a test pattern on a sheet having reference targets within a printable region of the sheet; using a scanner, scanning the printed sheet to generate an image bitmap of the test pattern-bearing sheet larger than the sheet itself so that the image bitmap contains the sheet edges and measuring in numbers of pixels the distances between the reference targets and/or sheet edges using multiple swaths of the image bitmap itself as the measuring tool; and, using a processor and based on the measured distances, calculating error-associated adjustment values in millimeters to use to correct errors in the registration setup of the image-to-paper in the printer and transferring the error-associated adjustment values to the printer to perform adjustment of its setup actuators.

Abstract: A toner formulation is disclosed comprising a binder and an IR absorbing black pigment at a concentration of 0.25-2.0% by weight, including one or more infrared transmissive pigments, wherein the infrared transmissive pigments are configured to provide a black color. Such toner formulation may provide a response to a toner patch sensor to indicate a mass per unit area of 0.1-1.5 mg/cm2 or a reflectance relative to a substrate to define a reflectance ratio that varies relative to L* values for the toner over the range L*=0-50 or a bulk reflectivity of greater than 6.0% for a portion of the wavelength range of 850-2000 nanometers.

Abstract: A toner formulation is disclosed comprising a binder, an IR absorbing colorant, and one or more infrared transmissive colorants, wherein the colorants are configured to provide a low reflectivity in the visible region of the spectrum and an intermediate reflectivity in the near infrared region of the spectrum when the toner is printed and fused onto paper.

Abstract: A method for reducing the occurrence of print artifacts in an imaging machine includes the steps of applying an electronic printhead skew correction to image data corresponding to at least one of a plurality of image planes, e.g., of a cyan image plane, a magenta image plane, a yellow image plane and a black image plane, to generate skew corrected image data. Thereafter the associated halftone screens are modified to eliminated halftone noise introduced by the electronic printhead skew correction. If text characters are present, block boundaries are effectively shifted to reside in the spaces between adjacent text characters.

Abstract: A toner patch sensor for use in an image forming device may be operated in different modes according to the color of the patch being sensed. The toner patch sensor may include a detector and a source adapted to transmit light that is reflected off a toner patch and towards the detector. The detected light may be specular and/or diffuse. A controller may selectively change the amount of one or both of the specular and diffuse light received by the detector. The source may include separate emitters for the specular and diffuse light, with the controller selectably turning off one of the emitters or selectably adjusting a ratio of illumination power between the emitters. Alternatively, the source may include a single emitter and an optical element to split light between specular light and diffuse light. Diffuse light may be blocked when sensing black toner patches.

Abstract: A method and system for carrying out an image-to-paper printer registration setup includes: using a printer undergoing registration setup, printing a test pattern on a sheet having reference targets within a printable region of the sheet; using a scanner, scanning the printed sheet to generate an image bitmap of the test pattern-bearing sheet larger than the sheet itself so that the image bitmap contains the sheet edges and measuring in numbers of pixels the distances between the reference targets and/or sheet edges using multiple swaths of the image bitmap itself as the measuring tool; and, using a processor and based on the measured distances, calculating error-associated adjustment values in millimeters to use to correct errors in the registration setup of the image-to-paper in the printer and transferring the error-associated adjustment values to the printer to perform adjustment of its setup actuators.

Abstract: A toner formulation is disclosed comprising a binder and an IR absorbing black pigment at a concentration of 0.25-2.0% by weight, including one or more infrared transmissive pigments, wherein the infrared transmissive pigments are configured to provide a black color. Such toner formulation may provide a response to a toner patch sensor to indicate a mass per unit area of 0.1-1.5 mg/cm2 or a reflectance relative to a substrate to define a reflectance ratio that varies relative to L* values for the toner over the range L*=0-50 or a bulk reflectivity of greater than 6.0% for a portion of the wavelength range of 850-2000 nanometers.

Abstract: A toner formulation is disclosed comprising a binder, an IR absorbing colorant, and one or more infrared transmissive colorants, wherein the colorants are configured to provide a low reflectivity in the visible region of the spectrum and an intermediate reflectivity in the near infrared region of the spectrum when the toner is printed and fused onto paper.

Abstract: Control circuitry associated with an electrophotographic imaging device is adapted to operate in conjunction with a sensor to adjust a difference in electrical bias between a photoconductive surface and an associated roller. The sensor detects a reflectance or luminosity of a developed image and the control circuitry uses this detected information and information related to reflectance or luminosity of the underlying surface and the developing toner to determine whether the developed image is produced as desired. The control circuitry adjusts the difference in electrical bias between the photoconductive surface and an associated roller in response to a comparison between the detected and desired images. In one embodiment, a predetermined test pattern is developed over a range of electrical bias differences and an optimum operating point is determined from the iterations.

Abstract: Control circuitry associated with an electrophotographic imaging device is adapted to manage bias levels of components in an image forming unit. A photoconductive surface is charged to a first bias level, a developer member is charged to a second bias level, and an imaging unit selectively discharges image feature locations on the photoconductive surface to a third bias level. In certain regions having a predetermined image feature density, the imaging unit may discharge an area in the vicinity of the image features to a fourth bias level that is between the first and third bias levels. The amount by which the imaging unit discharges the area in the vicinity of the image features changes as image feature density changes and as the difference between the first and third bias levels change.

Abstract: Control circuitry associated with an electrophotographic imaging device is adapted to operate in conjunction with a sensor to adjust operating parameters, including an imaging power. The sensor detects a reflectivity of a developed image and the control circuitry uses this detected information and information related to reflectivity of the underlying surface and the developing toner to determine whether the developed image is produced as desired. The control circuitry adjusts imaging power in response to a comparison between the detected reflectivity and a target reflectivity. In one embodiment, a predetermined halftone pattern is developed over a range of imaging powers and an optimum operating point is determined from the iterations. A predictive model may be generated based on many data points to select imaging power based on optimized surface potentials.

Abstract: A toner patch sensor for use in an image forming device may be operated in different modes according to the color of the patch being sensed. The toner patch sensor may include a detector and a source adapted to transmit light that is reflected off a toner patch and towards the detector. The detected light may be specular and/or diffuse. A controller may selectively change the amount of one or both of the specular and diffuse light received by the detector. The source may include separate emitters for the specular and diffuse light, with the controller selectably turning off one of the emitters or selectably adjusting a ratio of illumination power between the emitters. Alternatively, the source may include a single emitter and an optical element to split light between specular light and diffuse light. Diffuse light may be blocked when sensing black toner patches.

Abstract: Methods and devices for setting an operating point within an image forming device. The operating point for one or more image forming stations may be determined without performing a toner patch sensing procedure. The operating points are determined based on other information, such as the operating points of one or more other image forming stations, information about the device, and information about the image forming stations themselves. The different factors may be weighted to more accurately determine the operating parameter(s).

Abstract: A method of determining misalignment of color planes within an image forming apparatus. A first pattern is formed with a first color and comprises first and second sections. A second pattern is formed with a second color and positioned within the first and second sections of the first pattern. The alignment of the two color planes is determined by the difference in the amount of color within the first and second sections. The amount of misalignment may further be determined by the ratio of the difference in the amount of color within the sections and the sum of the amount of color within the sections. Perfect alignment of the two color planes results in equal color amounts in each section.

Abstract: A method of calibrating an electrophotographic machine having an image bearing surface includes depositing a toner patch on the image-bearing surface. The toner patch has a nominal coverage that varies substantially continuously from end to end. Light is emitted onto a selected one of the areas of the toner patch. An amount of light that is reflected off of the selected one area of the toner patch is measured. The emitting and measuring steps are repeated for each of a plurality of different areas of the toner patch. At least one electrophotographic condition is adjusted. The adjusting is dependent upon the measuring steps.

Abstract: A method of determining misalignment of color planes within an image forming apparatus. A first pattern is formed with a first color and comprises first and second sections. A second pattern is formed with a second color and positioned within the first and second sections of the first pattern. The alignment of the two color planes is determined by the difference in the amount of color within the first and second sections. The amount of misalignment may further be determined by the ratio of the difference in the amount of color within the sections and the sum of the amount of color within the sections. Perfect alignment of the two color planes results in equal color amounts in each section.

Abstract: A method of calibrating an electrophotographic machine having an image bearing surface includes depositing a toner patch on the image-bearing surface. The toner patch has a nominal coverage that varies substantially continuously from end to end. Light is emitted onto a selected one of the areas of the toner patch. An amount of light that is reflected off of the selected one area of the toner patch is measured. The emitting and measuring steps are repeated for each of a plurality of different areas of the toner patch. At least one electrophotographic condition is adjusted. The adjusting is dependent upon the measuring steps.

Abstract: An electrophotographic machine has at least two printing modes, with each printing mode having a respective printing density. A method of calibrating the electrophotographic machine includes depositing at least one toner patch on an image-bearing surface. The depositing is performed in a first of the printing modes. Light is emitted onto the at least one toner patch. An amount of light that is reflected off of the at least one toner patch is measured. At least one first electrophotographic condition for the first printing mode is adjusted dependent upon the measuring step. At least one second electrophotographic condition is adjusted for a second of the printing modes. The adjusting of the at least one second electrophotographic condition is dependent upon the measuring step.

Abstract: A method and apparatus provides for minimizing visual artifacts resulting from laser scan process direction position errors in an electrophotographic machine. The electrophotographic machine has a process direction, and includes a photoconductive member having an image forming surface having defined thereon a plurality of pixel locations which form a pixel grid, and wherein two adjacent pixels in the process direction are separated by a pixel spacing distance. A printhead unit has a first laser beam generator and a second laser beam generator, wherein the first laser beam generator generates a first laser beam which impinges the surface at a first location and the second laser beam generator generates a second laser beam which impinges the surface at a second location. The second location is spaced apart from the first location in the process direction by a separation distance equal to an integer multiple of the pixel spacing distance plus a distance less than the pixel spacing distance.