An image forming device includes an image data acquirer acquiring image data, a laser source emitting a laser beam, a laser driver forming an electrostatic latent image by irradiating a scanning surface of a charged photoconductor with the laser beam, based on the image data, a shading characteristic corrector correcting light quantity of the laser beam, an image former forming an image based on the electrostatic latent image, and a controller controlling the image data acquirer, the laser driver, the shading characteristic corrector, and the image former. The shading characteristic corrector includes a PDM signal outputter outputting a pulse density modulation signal based on the correction of the light quantity of the laser beam, a smoothing circuit smoothing the pulse density modulation signal to obtain an analog signal to be output, and a spread clock outputter outputting a clock subjected to spread spectrum to the PDM signal outputter.

A method for reducing image burn-in artifacts in an electrophotographic printing system, includes receiving a print job including image data for a set of pages to be printed. The pages are analyzed to determine that the image data for a sequence of pages in the print job are similar. The similar pages are printed using a pattern of lateral translations wherein the image data is laterally translated such that it is printed at a different lateral position on the printed page.

A print head includes a first emitting element on a substrate facing a lens. A light output level of the first element is controllable to be within a predetermined range. A second emitting element on the substrate has a light output level that is not controllable to be within the predetermined range. A first driving circuit is connected to the first emitting element. A capacitor is in the first driving circuit and the current supplied to the first emitting element is set by the capacitor voltage. A second driving circuit is connected to the second emitting element to supply current to the second emitting element. A memory stores correction values for the setting of the capacitor voltages for the first and second driving circuits. When capacitor voltage for the second driving circuit is set according to the stored correction value, the capacitor voltage is less than a predetermined threshold.

A light source adjustment apparatus is disclosed. The light source adjustment apparatus includes processing apparatus to receive a scanned image of a pattern printed by a print apparatus onto a printable medium, the pattern including a plurality of blocks of print agent of a first colour printed during a printing operation in which light sources of a light source array irradiate a photoconductive surface; analyse the scanned image to identify a region of non-uniformity within the plurality of blocks of print agent; correlate a location of the identified region of non-uniformity with a corresponding light source in the light source array; determine, based on the identified region of non-uniformity, an adjustment to be made to a parameter of the corresponding light source; and generate a signal to effect the determined parameter adjustment with regard to the corresponding light source. A method and a print apparatus are also disclosed.

An image forming device includes an image data acquirer acquiring image data, a laser source emitting a laser beam, a laser driver forming an electrostatic latent image by irradiating a scanning surface of a charged photoconductor with the laser beam, based on the image data, a shading characteristic corrector correcting light quantity of the laser beam, an image former forming an image based on the electrostatic latent image, and a controller controlling the image data acquirer, the laser driver, the shading characteristic corrector, and the image former. The shading characteristic corrector includes a PDM signal outputter outputting a pulse density modulation signal based on the correction of the light quantity of the laser beam, a smoothing circuit smoothing the pulse density modulation signal to obtain an analog signal to be output, and a spread clock outputter outputting a clock subjected to spread spectrum to the PDM signal outputter.

A light emitting device includes a light-emitting element row that includes light emitting elements arranged in a row in a main scanning direction, an optical element that is used for forming an electrostatic latent image by focusing light outputs of the light emitting elements and exposing a photoconductor to light and a control unit that controls light emission of the light-emitting element row. The light-emitting element row is divided into groups, and the control unit uniformly corrects a light intensity of each of the light emitting elements included in the groups on a group-by-group basis by a first correction method so as to correct density unevenness in the main scanning direction.

A method for reducing image burn-in artifacts in an electrophotographic printing system, includes receiving a print job including image data for a set of pages to be printed. The pages are analyzed to determine that the image data for a sequence of pages in the print job are similar. The similar pages are printed using a pattern of lateral translations wherein the image data is laterally translated such that it is printed at a different lateral position on the printed page. The similar pages can also be printed using a pattern of page orientations including a first page orientation and a second page orientation, wherein the image data for the second page orientation is rotated 180 degrees relative to the image data for the first page orientation.

An image forming apparatus includes: an image carrier; a light source configured to emit light for exposing the image carrier; a controller configured to control a light intensity of the light source; a reference current generator configured to generate a reference current based on a target light intensity of the light source, the target light intensity being set by the controller; a correction current generator configured to generate a correction current for correcting the reference current based on an amount of correction that is set by the controller, and on the target light intensity; and a driver configured to drive the light source using a drive current that corresponds to a difference between the reference current and the correction current.

A development bias to be applied onto a developing unit is reduced, in a case where it is determined that a remaining amount of toner is equal to or less than a threshold, in a mode in which a rotation speed of a developing unit is faster than a rotation speed of an image bearing member to increase an amount of toner to be supplied to the image bearing member.

A development bias to be applied onto a developing unit is reduced, in a case where it is determined that a remaining amount of toner is equal to or less than a threshold, in a mode in which a rotation speed of a developing unit is faster than a rotation speed of an image bearing member to increase an amount of toner to be supplied to the image bearing member.