Abstract: When an image forming apparatus, after a feeding error of a recording material occurs in a fixing device, re-forms on the recording material an image corresponding to image data which image was formed on a sheet which caused the feeding error, an image forming condition is caused to be different from an operation condition used when the feeding error has occurred. This makes it possible to prevent a JAM corresponding to the same image from recurring in the fixing device.

Abstract: The life of the photoconductor in an image forming apparatus is typically limited by the eventual occurrence of some form of print quality defect related to the photoconductor. One of the typical failure mechanisms is the slow wearing away of the surface layer of the photoconductor. Photoconductor run life is improved by operating a charging station in a low wear mode during certain circumstances, including: during printing of a low stress page as detected based on the image data; during at least one of cycle up and cycle down operations to control charging of the at least one photoconductor over at least one print zone for at least one cycle of rotation of the at least one photoconductor; during printing of at least one test patch in a process control cycle; and upon determination from the image data that at least one photoconductor will not contribute to the printing during a next print cycle.

Abstract: An image forming apparatus forming a preferable image without white dots caused by excessive charging when a halftone image is formed by providing a potential difference between a surface potential of a photosensitive drum immediately before charging by a charging device, and that of the drum after the charging in an image forming area of the drum. At least one of a charging bias and a transfer bias is changed between a first area and a second area. The first area is an area on the drum that passes a transfer portion when a recording medium is not present between the roller and the drum, and on that a latent image is to be formed. The second area is an area on the drum that passes the transfer portion when the medium is present between the roller and the drum, and on that a latent image is to be formed.

Abstract: An image forming apparatus including: an image forming section for forming an image, the image forming section including a photoconductor, a charging unit, a developing unit, a toner supply unit which supplies a toner to said developing unit, and a developing bias power supply section which supplies a developing bias voltage to said developing unit; and a controller that activates said image forming section, determines a target value of a charging potential of said photoconductor and/or a developing bias voltage, for forming the image, and controls the charging unit and/or the developing bias power supply section in accordance with a determined result, wherein when an absolute value of the determined target value of the charging potential or an absolute value of the determined developing bias voltage is larger than a prescribed value, said controller controls replacement of a prescribed amount of a toner in the developing unit.

Abstract: The size of a resonance noise due to a signal of an alternating voltage applied to a charging member (charging roller) is detected by a piezoelectric device (PZ), and in cases in which the size of the detected resonance noise (detection signal level) exceeds a predetermined size, the frequency of the alternating voltage signal applied to the charging member is shifted, by a control unit (50), by a predetermined frequency amount only.

Abstract: A developing method in an image-forming device is provided. The developing method includes the steps of charging a photoreceptor; exposing the photoreceptor to form a first latent image on the photoreceptor; developing the first latent image by a first developing unit having a first potential to form a first toner image; and discharging the photoreceptor having the first toner image, such that when the photoreceptor is charged again, the first toner image on the photoreceptor has a second potential, and the second potential is approximately the same as the first potential of the first developing unit.

Abstract: An image forming apparatus, includes: a plurality of image forming stations each of which includes a photosensitive member and a charger that charges a surface of the photosensitive member to a specified surface potential, and is adapted to execute an image forming operation of forming an electrostatic latent image on the photosensitive member charged by the charger and developing the electrostatic latent image with toner to form an image; a plurality of direct-current bias generators that are provided corresponding to the respective plurality of chargers and generate direct-current voltages as direct-current components of charging biases to be given to the chargers; a plurality of series resistors that are provided corresponding to the respective plurality of chargers and electrically connect the plurality of chargers and the direct-current bias generators corresponding to the chargers in a one-to-one relationship; an alternating-current bias generator that generates alternating-current voltages as alternati

Abstract: An image forming apparatus, includes: an image carrier that carries a developer image by a charge layer provided on a surface of the image carrier; a charger that charges the image carrier; a feeder that feeds the charger with a charge; a total charge amount detector that detects the total amount of the charge output by the feeder; an unsupplied charge amount calculator that calculates the amount of the charge output by the feeder but not supplied to the charger; and a layer thickness calculator that calculates the thickness of the charge layer based on the unsupplied charge amount calculated by the unsupplied charge amount calculator and the total charge amount detected by the total charge amount detector.

Abstract: A charging apparatus includes a charger for being supplied with an AC voltage and for electrically charging a member to be charged; a current measurer for measuring a current flowing between the charger and the member to be charged when the AC voltage is supplied to the charger; and a particular current extractor for extracting from the current a particular current having a particular frequency.

Abstract: A ghost removing device for a marking apparatus includes a photoreceptor, a primary charging device, an erase light generating device to generate an erase light when activated, a voltage source to supply a charge voltage to the primary charging device, and a controller configured to control the at least one voltage source to supply the charge voltage to the primary charging device and to activate the erase light generating device substantially simultaneously after transfer of a toned image within a marking cycle. A ghost removing method for a marking device with a photoreceptor, including performing a partial print cycle, applying an erase light to the photoreceptor, and applying a charge voltage to the photoreceptor, wherein the erase light and the charge voltage are applied to the photoreceptor substantially simultaneously after completion of the partial cycle.

Abstract: In a charging device having saw-tooth electrodes for generating corona discharges, an amount of dust, toner, or paper dust attached to the tip end portions of saw-tooth electrodes is reduced. First to third pairs of saw-tooth electrode plates are disposed in a side-by-side fashion along the periphery of a photosensitive drum in which the first pair is disposed at an upstream side with respect to a direction in which the photosensitive drum rotates, the third pair at a downstream side, and the second pair at a central portion between the remaining two. A current flowing per a unit length of the second pair is set to 1.3 to 3 times as much as a current flowing per a unit length of each of the first and third pairs. The currents flowing per a unit length of the first and third pairs are set to be equal to each other.

Abstract: A non-contact charger includes: a casing having a recessed portion in which a cordless handset is placeable; a primary coil which is provided in the casing to be opposed to the cordless handset upon placement of the cordless handset in the recessed portion of the casing; an oscillating portion which is oscillatable to generate a magnetic flux energy from the primary coil; a detecting portion which detects at least one of a current value and a voltage value in the oscillating portion; and a controller which stops a generation of the magnetic flux energy based on at least one of the current value and the voltage value detected by the detecting portion.

Abstract: This is a charging assembly that is useful in marking processes with an electrostatically charged surface. The assembly includes, besides the charger, a controller and an electric field probe. Charge and current flows can be detected by the probe and corrected immediately after detection of flaws by the probe and conveyed to the controller. If flaws in the charger are determined by the probe, corrections are made to the output by a controller; this is done before a final copy or print is made. The term flaws as used means any non-uniform appearing region in the printed image or any void region within the printed image including any otherwise unacceptable defect such as a jagged line that is visible to an end user. The probe is enabled to detect and indicate flaws and the controller which is in communication with the probe takes corrective action on the flaws. The probe used is a novel probe having two sensing elements surrounded by one or more reference electrodes.

Abstract: A pulse-like DC voltage is applied from two power sources to transfer residual toner uniformizing means and toner charge amount control means, respectively, to expel transfer residual toner deposited on these means from these means onto a photosensitive drum. In a low humidity environment, the number of application of the DC voltage is increased so as to sufficiently expel the transfer residual toner because the transfer residual toner is less liable to be expelled even when the pulse-like DC voltage is applied to the above two means in the low humidity environment in which an absolute moisture content in atmosphere is small and electrical resistances at portions of a photosensitive drum contacting the above two means.

Abstract: An image forming apparatus includes an image carrier, a charging unit configured to charge the image carrier, an exposing unit configured to form an electrostatic latent image on the charged image carrier, a developing unit configured to develop the electrostatic latent image formed on the image carrier with a development material for forming a development image, an intermediate transfer member that includes a multilayer structure having a conductive layer; a transfer unit configured to transfer the development image on the intermediate transfer member, and a control unit that controls a transfer potential and a charging potential so that a potential difference between the transfer potential and a non-image portion potential on the image carrier in a transfer position falls within a predetermined range.

Abstract: According to an aspect of the invention, an image forming apparatus having a plurality of processing velocities is characterized by a control for determining the image forming process conditions by redefining a first approximate expression for estimating the unexposed surface potential value Vo of a photoconductive drum as a continuous function of the charging potential Vd according to the change of the natural environmental temperature, the change of the surface temperature of the photoconductive drum, the change of the photoconductive drum due to fatigue, or the exposure value, and a second approximate expression for estimating the exposed surface potential value VL of the photoconductive drum as a continuous function of the charging potential Vd according to the change of the processing velocity, using the first approximate expression and the second approximate expression to determine the optimal values of the developing potential, the background potential, and the exposure value for the respective process

Abstract: System and methods may calibrate an AC rms voltage applied to a coronode of a charging device to achieve a predefined operating current at a target value of DC shield voltage. The target value of DC shield voltage may be set to be substantially below an over-voltage condition. System and methods may use a calibration routine that may determine a minimum AC voltage required to achieve the target value of DC shield voltage. Systems and methods may alternatively, or additionally, sense current and adjust the applied voltage to obtain a target current.

Abstract: A xerographic marking engine adjusts a charging actuator, such as an AC peak-to-peak voltage or an AC peak-to-peak AC current, based upon toner patch density measurements made using, e.g., a toner patch density sensor. The sensor is used to detect a knee in a toner mass density curve obtained by sweeping an AC peak-to-peak voltage or an AC peak-to-peak current. Once the knee is located, an AC charging actuator peak-to-peak voltage or AC peak-to-peak current is determined that reduces the amount of positive charge that is deposited onto the surface of the photoconductor, thereby extending its life while maintaining acceptable print quality. The described approach may improve photoconductor life without significantly increasing production costs or complexity.

Abstract: An image forming apparatus includes an image forming part that forms an image on a recording medium and includes a plurality of photoconductors, a plurality of charging parts that charges the photoconductors, a plurality of developing parts that develops the charged photoconductors, and a plurality of static electricity erasing parts that erases surface potentials of the charged photoconductors. A power supplying part supplies power to the image forming part, and a controller controls to switch the operation of the static electricity erasing parts independently and controls the image forming part to form the image on the recording medium if power applied to the respective photoconductors through the charging parts and the developing parts reaches a target value.

Abstract: An image forming apparatus includes devises for performing a detection method which detects an image characteristic of an image formed on an image bearing member; a first control method which controls a toner concentration in a developer, based on a detection result by the detection method, of an image characteristic of a first reference image for a first control for controlling the toner concentration; a second control method which controls an image parameter, different from the toner concentration, thereby controlling an image density, based on a detection result of an image characteristic of a second reference image for a second control, different from the first reference image; and a correction method which receives detection results of both image characteristics of the first and second reference images, and which, based on the detection result of the image characteristic of either of the reference images for the first and second controls, corrects the other control.

Abstract: Xerographic photoreceptor life is improved while maintaining output print quality by adjusting the AC charging actuator of a xerographic machine to a point at which photoconductor life is optimized while maintaining output print quality. Where the actuator is voltage, the actuator is set a predetermined amount above the knee voltage of the photoreceptor surface potential versus peak-to-peak voltage curve, which is determined during operation of the machine. Instead of determining the knee voltage, calibration sheets can be generated for various values of the actuator, the best sheet with the least possible actuator value is selected, and the AC charging actuator is set to the value corresponding to the best sheet. The sheets can be evaluated by a user, or an optical array sensor can be used to scan the sheets so that the controller can compare the sheets to stored criteria to automatically select the best sheet and set the actuator.

Abstract: Embodiments of the present invention include an image bearing member arranged to bear an electrostatic latent image, a charging member contacting the image bearing member to charge a surface of the image bearing member with application of a DC voltage to the charging member, a current detection unit arranged to detect a DC current flowing in the charging member, and a control unit configured to control the voltage applied to the charging member, wherein a plurality of different DC voltages are successively applied to the charging member during a period of no image formation until a change amount of change in the DC current with respect to change in the DC voltage becomes not larger than a predetermined value, and the control unit controls a DC voltage applied to the charging member during a period of image formation based on a result detected by the current detection unit.

Abstract: A charger includes: a charging brush which is rotatably provided and is brought into contact with an image carrier to charge the surface of the image carrier; a charging roller which is brought into contact with the image carrier at a portion on the downstream side relative to the charging brush in the rotational direction of the image carrier to charge the surface of the image carrier; and a controller which controls voltages applied to the charging brush and charging roller, wherein the controller controls voltages applied to the charging brush and charging roller such that one-fifth of the absolute value of a charging brush current flowing between the image carrier and charging brush is lower than the absolute value of a charging roller current flowing between the image carrier and charging roller.

Abstract: A charger includes: a primary charging member which is rotatably provided and is brought into contact with an image carrier to charge the surface of the image carrier; a secondary charging member which is brought into contact with the image carrier at a portion on the downstream side relative to the first charging member in the rotational direction of the image carrier to charge the surface of the image carrier; and a controller which controls voltages applied to the first and second charging members, wherein at the time of image formation, the controller applies, to the first charging member, a voltage whose absolute value is higher than the absolute value of the discharge start voltage of the first charging member and applies, to the second charging member, a voltage whose absolute value is lower than the absolute value of the discharge start voltage of the second charging member and whose absolute value is lower than the voltage applied to the first charging member, and at the time when an image is not for

Abstract: An image forming apparatus performs a control sequence in which an AC voltage having a peak-to-peak voltage is applied to a charging member so that a relationship between an absolute value of a surface potential of an image bearing member at a portion under a transfer residual toner remaining on the image bearing member which has been electrically charged by the charging member during non-image formation and an absolute value of a surface potential of a developer carrying member is reversed with respect to a relationship between these absolute values during image formation.

Abstract: Image forming apparatus in which surface electric potentials of a plurality of surface areas are detected by charging a photoconductor with a different applied bias for each predetermined timing and exposing a plurality of surface areas of the photoconductor by scanning the photoconductor with an optical beam, while changing an exposure intensity of the optical beam for each of the surface areas of the photoconductor. Then, the applied bias necessary for obtaining a predetermined electric potential of a dark section and the exposure intensity of the optical beam necessary for obtaining a predetermined electric potential of a bright section are controlled, on the basis of the surface electric potentials that are detected respectively from the different applied biases and the different exposure intensities. Thereby, the adjustment time can be made shorter than the conventional case.

Abstract: An image forming apparatus includes a movable image bearing member; charging means for electrically charging the image bearing member; voltage applying means for applying to the charging means an oscillating voltage including an oscillating component and a constant component in one cycle; discharging means for selectively discharging an electrically charged surface of the image bearing member to form an electrostatic latent image; and changing means for changing an application time of the constant component during the one cycle depending on a spatial frequency, with respect to a movement direction of the image bearing member, of the electrostatic latent image to be formed.

Abstract: A charging device includes a charging member that charges a body to be charged; a detector that detects an AC component of a current flowing through the charging member; an integration section that integrates the AC component of the current detected by the detector; a controller that controls the current flowing through the charging member, according to a result of integration executed by the integration section; a periodic signal generating section that generates a periodic signal having a cycle period corresponding to a cycle period of the AC component; and an integration period adjusting section that adjusts a period of integration executed by the integration section, with reference to the periodic signal.

Abstract: The present invention provides a method and apparatus for forming an image. A controller manages a charger and a developing bias voltage to increase an absolute value of the charging voltage to an image-bearing member and an absolute value of a developing bias voltage to a developer-bearing member to predetermined values in a plurality of steps. The controller controls the developing bias voltage applied to the developer-bearing member; wherein the following relation holds in each of the plurality of steps: |VD|>|Vi|, where VD represents a developing bias voltage applied to the developer-bearing member and Vi represents a charged potential of the image-bearing member. This invention is especially useful for mono-component development using DC voltage as a development driving mechanism.

Abstract: The life of the photoconductor in an image forming apparatus is typically limited by the eventual occurrence of some form of print quality defect related to the photoconductor. One of the typical failure mechanisms is the slow wearing away of the surface layer of the photoconductor. Photoconductor run life is improved by operating a charging station in a low wear mode during certain circumstances, including: during printing of a low stress page as detected based on the image data; during at least one of cycle up and cycle down operations to control charging of the at least one photoconductor over at least one print zone for at least one cycle of rotation of the at least one photoconductor; during printing of at least one test patch in a process control cycle; and upon determination from the image data that at least one photoconductor will not contribute to the printing during a next print cycle.

Abstract: An image forming apparatus forming a preferable image without white dots caused by excessive charging when a halftone image is formed by providing a potential difference between a surface potential of a photosensitive drum immediately before charging by a charging device, and that of the drum after the charging in an image forming area of the drum. At least one of a charging bias and a transfer bias is changed between a first area and a second area. The first area is an area on the drum that passes a transfer portion when a recording medium is not present between the roller and the drum, and on that a latent image is to be formed. The second area is an area on the drum that passes the transfer portion when the medium is present between the roller and the drum, and on that a latent image is to be formed.

Abstract: Provided are a high voltage generator of an image forming apparatus, which simplifies a circuit structure and reduces the number of control signals by commonly using a roller resistance sensing circuit unit, and a method of sensing roller resistance. The high voltage generator applies high voltages to a plurality of rollers included in the image forming apparatus and senses resistance values of the rollers. The high voltage generator includes a plurality of voltage-pumping circuit units for providing high voltages to the respective rollers. A plurality of high voltage divide circuit units divide the high voltages output from the voltage-pumping circuit units. A multiplexer receives a plurality of divide signals output from the high voltage divide circuit units, selects and outputs a divide signal, which corresponds to a resistance of a roller to be sensed, based on a predetermined select signal.

Abstract: An image forming apparatus includes at least one image forming section, which includes an image bearing body, a charging unit that charges an area on a surface of the image-bearing body, and a developing unit that supplies a developer material to the charged area to form a developer image on the image bearing body. The developer image is transferred from the image-bearing body onto a transporting unit. A detector detects a density of the developer image on the transporting unit. The controller performs a charging voltage correcting operation in which the controller provides a test charging voltage to the charging unit for forming the developer image, and then a normal charging voltage for normal printing is determined based on the density. The controller also performs a developer-supplying voltage correcting operation in which a developer-supplying voltage supplied to a developer supplying unit is determined based on the density.

Abstract: An image forming apparatus comprising: a section for obtaining a property of a recording material; an adjusting section for adjusting a toner amount of a toner image formed by development depending on the property of the recording material; a charging section for charging the toner image before transfer; and a controlling section for adjusting a charging quantity by the charging section depending on the toner amount, wherein an appropriate quantity of charge depending on the toner amount is given to the toner image before transfer to the recording material, thus depending on the property of the recording material, an appropriate toner amount is transferred at a high transfer efficiency, and uniformity of a solid concentration is ensured.

Abstract: A charging unit is disclosed capable of reducing undue variation and fluctuation margin of a charging gap, and controlling accurately the proper gap durably over the change of environmental conditions, which is suitably incorporated into an image forming apparatus. The charging unit is configured to charge an image bearing member in a non-contact arrangement, including a charging roller provided with a core shaft, a charging member formed of electroconductive resin integrally disposed on the periphery of the core shaft, and gap holding members formed of insulating resin each disposed at respective ends of the charging member outside an image forming region. The control of the charging gap is feasible by either forming the gap with a charging member having such a materials condition as to satisfy the relation, |G30?G10|×5<G20, where G10, G20 and G30 are the gap averages at 10°, 20° and 30° C.

Abstract: A sheet transport device and an image forming apparatus using the sheet transport device are disclosed. The sheet transport device includes a transport belt rotating around rollers that transports a sheet by attaching the sheet to the transport belt by an electrostatic force, and a charging unit that is unitized by including a charging member for charging the transport belt. The charging unit includes a unit case containing springs for pushing the charging member onto the transport belt. An Ac bias voltage is applied to the transport belt via the charging member.

Abstract: An image forming apparatus uses a charging roller to charge the surface of a photosensitive member to a predetermined potential. A current detector detects charging current when the charging bias is applied. A bias corrector corrects the charging bias and a storage stores a target charging current value when the photosensitive member is charged to a required potential. The bias corrector performs two corrections. The first correction compares a charging current value with a stored target charging current value, and determines a new bias based on the comparison. The second correction determines whether the bias obtained by the first correction is at a predetermined level or a higher level, and when the corrected charging bias is at the higher level, changes the target charging current value in accordance with the corrected charging bias and obtains a new charging bias on the basis of the changed target charging current value.

Abstract: An image forming device comprises: charging means for uniformly charging the surface of a photosensitive member; charging control means for controlling the charging output of the charging means; and table storing means for storing a plurality of control tables stipulating controlled variables for controlling the charging output in relation to the passage of time, the charging control means controlling the charging output based on one or more control tables selected from the plurality of control tables stored in the table storing means.

Abstract: An image forming apparatus, performing a corresponding method of image forming, includes an image carrier, a charging unit including a first charging member for discharging a given amount of bias to a portion contacting the image carrier and uniformly charging the surface of the image carrier while contacting the surface of the image carrier, a charge bias applying unit for applying a charge bias including at least an alternating current voltage to the first charging member, a writing unit, and a developing unit. In the image forming apparatus, a ratio of a frequency of the alternating current voltage to a surface linear velocity of the image carrier is within a range of from approximately 1.5:1 to approximately 4:1 and a ratio of a surface linear velocity of the first charging member to the surface linear velocity of the image carrier is at least 2:1.

Abstract: Charging unit(s) is/are made versatile enough to be used in a plurality of image forming apparatus models having different processing speeds. Furthermore, in the context of an electrophotographic image forming apparatus permits selective switching between/among processing speeds, two charging units 5a, 5a having mutually identical configuration (e.g., charging units having case width 14 mm) are arranged within a single image forming unit (e.g., black image forming station Sa), the number of these two charging units 5a, 5a that is/are driven being switched in correspondence to processing speed(s) so as to make it possible for all of the charging units at image forming apparatus 100 to be accommodated by the same model.

Abstract: A diagnostic routine for determining the cause of color non-uniformity in a full color image forming device, by selecting a substation of one print station and using it in combination with a substation from another print station, while functionally omitting the intervening substations. The charge setting on the charge substation is adjusted to compensate for the increased distance between the charge substation, and the developing substation in this method.

Abstract: A first bearing member and a second bearing member fit in a first side and a second side of a rotating shaft in the axial direction, respectively. The first bearing member is held by a supporting portion provided in a casing on a side corresponding to an emplacing member of an image carrier drum. The second bearing member is held by fitting in a fit-in portion from inside. A wall surface that regulates a charging roller in a longitudinal direction is formed on the second bearing member to protrude from a wall surface rotatably and pivotally supporting the charging roller.

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: An image forming apparatus charges the surface of a photosensitive member to a predetermined potential. A current detector detects a charging current when the charging bias is applied. A storage stores a target charging current value when the photosensitive member is charged to a required potential. A usage acquiring portion acquires information relating to usage of the charging roller. A bias corrector performs first and second corrections. The first correction compares a charging current value with a stored target charging current value and determines a new charging bias based on the comparison. The second correction determines whether usage of the charging roller is a predetermined first amount or a greater amount based on acquired usage information, and when the usage is the greater amount, changes the target charging current value in accordance with the usage amount and obtains a new charging bias based on the changed target charging current value.

Abstract: A charging device includes a charging member disposed so as to rotate in contact with a surface of an image carrier to charge the image carrier surface, a bias voltage applying unit that applies a bias voltage to the charging member, the bias voltage having an AC voltage superimposed on a DC voltage, a DC current detector that detects a DC current flowing between the image carrier and the charging member, a filter that extracts only a specific component from the DC current detected by the DC current detector, and a controller that controls at least one of an AC voltage and an AC current to be applied to the charging member in accordance with an amount of variation of the specific component extracted from the DC current by the filter.

Abstract: An image forming apparatus of the present invention includes a pair of support plates supporting the rotary shaft of a photoconductive drum at axially opposite ends of the drum. One of the support plates is openable away from the body of the apparatus and loaded with a contact forming member including a current feed path for feeding a current from a high-tension power supply for charging to a charge roller, a wiring forming a current return path that allows a current to flow from the photoconductive drum to the ground of the power supply, and a plurality of contacts where the wiring and drum contact each other. A current flowing through the current return path is sensed to execute feedback control to the output of the high-tension power supply.

Abstract: An image forming device includes an image forming unit that includes an image carrier which carries an electrostatic latent image, a developing unit which forms a developing nip by contacting with the image carrier and develops the latent image by using toner, a transfer unit which forms a transferring nip by contacting with the image carrier and transfers a toner image onto a recording paper, and a first driving unit which rotates the image carrier, the developing unit and the transfer unit. The image forming device also includes a laser scanner unit that includes a polygon mirror and a second driving unit which rotates the polygon mirror.

Abstract: An electrostatic latent image is formed by controlling the amount of light, the emission time, and the like, considering the spot diameters of a laser, without changing the charging bias, the developing bias, and the like so as to obtain a plurality of correlations between density patches and development contrasts faithfully representing the developing characteristics of an image forming apparatus in a short time.

Abstract: An image forming apparatus according to the present invention is provided with a plurality of image bearing members, an intermediate transfer member, a plurality of first transfer devices, a second transfer device, and a charge amount adjustment section. The image bearing members carry images of respective colors. The intermediate transfer member is rotatably disposed at a position opposed to the image bearing members. The first transfer devices form a full-color toner image on the intermediate transfer member by transferring color toner images formed on the image bearing members to the intermediate transfer member. The second transfer device transfers the full-color toner image formed on the intermediate transfer member to a recording sheet. The charge amount adjustment section adjusts the charge amount of toner particles constituting the full-color toner image so as to reduce non-uniformity in a charge amount of toner particles of the full-color toner image on the intermediate transfer member per unit area.

Abstract: The present invention is an image forming apparatus containing an image holding body, a developer holding body for holding developer that forms a developer image by being affixed to the electrostatic latent image formed on the image holding body, a transfer unit for transferring the developer image to a medium, a fusion apparatus for fusing the transferred developer image onto the medium, an idle time judgment process section for making a judgment as to whether an idle time, from when printing is completed to when printing is initiated, of the image forming apparatus is long, and a surface potential setting process section for changing and setting a surface potential of the image holding body to a reference value at which fogging is not generated in a case where the idle time is long.