Abstract: An image forming apparatus controls a generation circuit to modulate a DC component of a developing voltage based on a first correction component such that a density unevenness is reduced. The image forming apparatus further restricts the first correction component for modulating the DC component of the developing voltage such that fogging of toner that may occur on a non-exposure region which is not exposed by an exposure unit and adhesion to a photosensitive member of carrier included in a developer are reduced.

Abstract: An image forming apparatus includes a photosensitive member, a developing member to supply a toner to the photosensitive member at a developing portion, and a transfer member to transfer a toner image to a recording material passing through a transfer portion from the photosensitive member. In a case which the transfer is performed to a shorter width recording material and thereafter, the transfer is successively performed to a longer width recording material, a control portion controls a first back contrast formed when an area of a surface of the photosensitive member corresponding to the transfer portion through which the shorter width recording material is passing reaches the developing portion, and a second back contrast formed when an area of the surface corresponding to the transfer portion through which the longer width recording material is passing reaches the developing portion so that the second back contrast is higher than the first back contrast.

Abstract: An image forming device comprising circuitry. The circuitry generates an image pattern in which two or more types of patch images are combined and changes a value of image data around at least one type of patch image of the two or more types of patch images to less than a maximum value of image data of the at least one type of patch image when the two or more types of patch images are combined.

Abstract: An image forming apparatus includes an image forming device, a first transfer device including a first mover, a second transfer device including a second mover, a transfer-pressure changer, a detector, and circuitry. The detector detects a toner image and outputs a detection value indicating an amount of toner of the toner image adhering to the second mover. The circuitry calculates a variable value for the amount of toner varying with a change in a transfer pressure, based on the detection value and a target value of the amount of toner of the toner image to be transferred and adhere to the second mover, reflects the calculated variable value in the detection value to correct the detection value, adjusts an image-forming condition based on the corrected detection value, and sets the image-forming condition of the toner image in the image forming device based on the corrected detection value.

Abstract: 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.

Abstract: A controller is able to, in a case where the controller receives a correction instruction for image density, execute a phase detection mode for detecting a phase of an image bearing member and detecting a phase of a developer bearing member and change an image forming condition for an image forming unit during an image formation mode based on respective phases of the image bearing member and the developer bearing member detected in the phase detection mode and an image density of a toner pattern, and a ratio of a circumferential velocity of the developer bearing member to a circumferential velocity of the image bearing member during the phase detection mode is different from a ratio of a circumferential velocity of the developer bearing member to a circumferential velocity of the image bearing member during the image formation mode.

Abstract: An image forming apparatus includes: an image forming mechanism that forms a first image on a recording medium based on an image forming condition; a detector that detects a first color of the first image and a color of a foundation under the first image from the recording medium on which the first image is formed; a storage that stores reference data for specifying a relative relationship between a position of the first color in a color space and a position of the color of the foundation in the color space; and a processing circuitry, wherein the processing circuitry corrects the image forming condition based on the reference data and the first color and the color of the foundation detected by the detector.

Abstract: An image forming apparatus includes an image forming unit to form an image based on an image forming condition and a controller. The controller determines information related to a density of an image to be formed by the image forming unit; generates the image forming condition based on the information; acquires measurement data outputted from a sensor related to a test image; determines, based on a first determination condition, first information related to a density of the test image; determines, based on a second determination condition, second information related to a density of the test image; and selects the determination condition from among a plurality of determination conditions including the first determination condition and the second determination condition.

Abstract: An image forming apparatus includes an image forming unit configured to form an image on a recording medium based on an image forming condition; an image reader configured to read an image for adjustment of the image forming condition, the image for adjustment being formed on the recording medium; and a controller configured to control the image forming unit to form images for adjustment; control the image reader to read the images for adjustment; determine target data based on a reading result of a first image included in reading results of the images for adjustment; and adjust the image forming condition, during execution of a job in which the image forming unit forms a plurality of images on a plurality of recording mediums, based on the target data and a reading result of second image included in the reading results of the images for adjustment.

Abstract: An image forming apparatus includes an image carrier, an image forming unit, an intermediate transfer belt, a power supply, a transfer member to transfer toner image on the intermediate transfer belt to a recording medium, and a sensor to detect, as density information, a density of the recording medium toner image. In an adjustment mode, (i) a test recording medium is output as a test chart by applying multiple levels of test voltages to the transfer member to transfer test toner images to the test recording medium, (ii) the transferred test toner images are detected via the sensor, and (iii) a transfer voltage is adjusted based on the sensor detection. In the adjustment mode, test toner image groups are set, one test toner image group is extracted based on an index value, and the transfer voltage is adjusted based on the density information of the extracted test toner image group.

Abstract: An image forming apparatus comprises an image forming unit; a sensor that measures a measurement image; and a controller. The controller controls the image forming condition based on a measurement result of measuring a first measurement image; acquires information having a correlation to density variation of images to be formed by the image forming unit; controls the image forming condition based on the information; determines a first value regarding a density of an image to be formed, based on a measurement result of measuring a second measurement image; determines a second value regarding a density of the image to be formed by the image forming unit, based on the information; and controls a timing at which the image forming unit next forms the first measurement image, based on the first value and the second value.

Abstract: A glossiness detector includes a glossiness sensor, a glossiness corrector, and a reference plate. The glossiness corrector corrects glossiness detected by the glossiness sensor. The reference plate is used for correction processing of the glossiness sensor. Then, the glossiness corrector acquires a glossy reflection profile of the reference plate that has been detected in advance. The glossiness corrector corrects the glossiness according to the reference plate on the basis of the glossy reflection profile and a gloss distribution of the reference plate that has been detected by the glossiness sensor.

Abstract: To provide an image forming device that can be efficiently maintained. According to one embodiment, the image forming device includes a plurality of photoconductors, an exposure device, a developer, and a processor. The exposure device irradiates a corresponding surface of the plurality of photoconductors with light corresponding to an image formed on a corresponding photoconductor of the plurality of photoconductors. The developer supplies a toner to the corresponding surface of the plurality of photoconductors on which an electrostatic latent image is formed by the light emitted by the exposure device. The processor adjusts, for every photoconductor, a contrast potential for supplying the toner from the developer to the electrostatic latent image formed on the corresponding surface of the plurality of photoconductors, and notifies a warning when there is a contrast potential whose difference from another contrast potential exceeds a reference value.

Abstract: An image forming apparatus includes an image forming unit configured to convey a recording medium and form an image on the recording medium based on an image forming condition; and a controller configured to control the image forming unit to form a test image and a scale image extending in a conveyance direction in which the recording medium is conveyed, obtain user instruction information related to a density fluctuation of the test image in the conveyance direction, and generate the image forming condition to suppress image density unevenness in the conveyance direction in an image to be formed by the image forming unit based on the user instruction information.

Abstract: A transfer unit includes first and second rollers, first and second bearing members, a roller holder, first and second urging members, a switching cam, and a driving mechanism. The switching cam includes first and second guide holes with which first and second engaging portions formed on the first and second bearing members engage. The first and second guide holes are formed, each in an approximately arcuate shape, at positions at different distances from the rotation center of the switching cam. By rotating the roller holder, one of the first and second rollers is arranged opposite an image carrying member and, by rotating the switching cam, the first or second roller arranged opposite the image carrying member is arranged selectively either at a reference position where the first or second roller is in pressed contact with the image carrying member or at a released position.

Abstract: An image forming apparatus includes a first generation unit to determine a density in each of a plurality of regions of a first image formed by the forming unit, and generate first correction data for correcting a density of an image to be formed by the forming unit for each of the plurality of regions based on the density. The first correction unit corrects the density of the image to be formed by the forming unit for each of the plurality of regions based on the first correction data stored by the first storage unit. The second generation unit determines a density of a second image formed by the forming unit, and generate second correction data based on the density. The first determination unit determines an amount of unevenness in the main scanning direction of formation density by the forming unit based on the density determined by the second generation unit.

Abstract: An image forming apparatus including a plurality of sheet feeding cassettes includes a control unit. The control unit performs control. In a case where a predetermined condition is satisfied during execution of a print job to print image data, the control unit performs control to execute interruption processing of a correction job to print a correction patch. The control unit performs control to determine, from the plurality of sheet feeding cassettes, a sheet feeding cassette to be used for the correction job based on information on the sheet feeding cassette used for the print job.

Abstract: According to one embodiment, an image forming device includes a memory and a processor. The memory is configured to store an execution history of image processing and an adjustment history of the image processing. The processor is configured to detect an occurrence of an event based on a correlation between the execution history and the adjustment history, and to execute instructing to output information according to a detection result.

Abstract: An image forming apparatus includes a platen on which an original is to be placed, a feeder configured to feed an original placed on a tray, a sensor configured to detect a sheet on the tray, a lamp provided to the feeder, a reader configured to read the original placed on the platen and to read the original conveyed by the feeder, an image forming unit configured to form an image on a sheet, and a controller. The controller is configured to control the image forming unit to form a test image on a sheet, control the reader to read the test image formed on the sheet placed on the platen, control a density of the image to be formed by the image forming unit based on a reading result of the test image.

Abstract: A method for reducing artifacts in an electrophotographic printing system includes receiving a print job including image data for a set of pages. The electrophotographic printing system is used to print a block of pages from the print job to provide corresponding printed pages. Image data for the block of pages is analyzed to determine a cross-track image profile for each page in the block of pages. Image data for a compensation image and a number of compensation images are determined, wherein the compensation image has a cross-track image profile which has an inverted shape relative to an average of the cross-track image profiles for the block of pages. The printing of the compensation images reduces image burn-in artifacts which result from the printing of the block of pages.

Abstract: To provide an image forming apparatus capable of achieving both correction accuracy of skew correction and minimization of a margin between images. A color shift amount calculator that calculates a color shift amount, and a first skew correction controller and a second skew correction controller that control skew correction of color shift are included. The first skew correction controller controls first skew correction by a mechanical operation by the image former on the basis of a first color shift residual target value set in advance. The second skew correction controller controls second skew correction, by image processing, of the color shift after the control by the first skew correction controller on the basis of a second color shift residual target value set in advance.

Abstract: An image forming apparatus includes image forming units having unit identification data, unit attachment portions having attachment portion identification data, an acquisition unit, a calculator, a storage unit, a controller, and a notification unit. The acquisition unit acquires data set of the two types of data. The calculator calculates data that are correction data for correcting image forming conditions or data on corrected image forming conditions. The storage unit stores the data set and the calculation data corresponding to the data set. The controller executes a data reuse control of controlling the image forming units using the calculation data that are stored in the storage unit and correspond to the data set after the data set is changed. The notification unit notifies execution-related information on execution of the data reuse control before the data reuse control.

Abstract: An image forming apparatus includes image forming units. A controller includes an execution section, a measurement section, and a prediction section. The execution section controls execution of a developer refresh operation in which toner is ejected from a developer bearing member to an image bearing member so that a specific image forming unit replenishes a development device with the toner from the developer bearing member. The measurement section measures respective surface potentials of the image bearing members included in other image forming units while the specific image forming unit is executing the developer refresh operation. The prediction section uses measurement results of the respective surface potentials of the image bearing members included in the other image forming units for a prediction on the surface potential of the image bearing member included in the specific image forming unit.

Abstract: An image forming apparatus that is capable of specifying a failed portion while preventing delay of an image forming operation appropriately. An image forming unit forms an image on a recording material. A detection unit detects an abnormality. A controller determines a type of an abnormality detected by the detection unit. The controller controls, in a case where the abnormality is detected by the detection unit, a start timing of failure diagnosis that specifies a failed portion that causes the abnormality according to the determined type of the abnormality.

Abstract: An image forming apparatus includes an optical sensor configured to detect an image formed on an intermediate transfer belt. The optical sensor includes a first light emitting diode (LED), a second LED, a first photodiode (PD), and a second PD on a substrate. The first PD is arranged at a position at which specularly reflected light of light emitted from the first LED can be received, and scattered reflected light of light emitted from the second LED can be received. The second PD is arranged at a position at which scattered reflected light of light emitted from the second LED can be received. A light receiving surface of the first PD and a light receiving surface of the second PD are formed at different angles. The light receiving surface of the first PD has an area that is smaller than an area of the light receiving surface of the second PD.

Abstract: An image forming apparatus includes a converter configured to convert image data with use of a tone correction condition corresponding to a position in a main scanning direction of the image data, and an image forming unit, which includes a photosensitive member and an exposure portion configured to expose the photosensitive member to light based on the converted image data, and is configured to form an image on a recording medium. The image forming apparatus further includes a holding portion configured to hold a plurality of feedback conditions corresponding to a plurality of tones and a controller configured to control the image forming unit to form a plurality of test images, acquire measurement results for the plurality of test images, and generate the tone correction condition based on the measurement results and the plurality of feedback conditions.

Abstract: An image reading apparatus includes a conveyance roller to convey a sheet, a light source to illuminate an image on the sheet while being moved in a predetermined direction above the conveyed sheet, a reading sensor to read the image on the sheet while being moved in the predetermined direction above the conveyed sheet, and a controller. The controller controls the reading sensor to read a first image for generating a color profile on a first sheet after the light source emits light for a duration of a first time. The controller controls the reading sensor to read a second image for detecting density unevenness in a main scanning direction of the image forming apparatus on a second sheet after the light source emits light for a duration of a second time shorter than the first time.

Abstract: An image forming apparatus includes an image processor configured to convert image data based on a first conversion condition; an image forming unit configured to form an image on a sheet based on the image data converted by the image processor, the image forming unit having an image bearing member on which the image is to be formed, a transfer unit configured to transfer the image from the image bearing member onto the sheet, and a fixing unit configured to fix the image to the sheet; a conveyance roller configured to convey the sheet having the image fixed thereto; a reading unit configured to read a pattern image on the sheet conveyed by the conveyance roller; and a detector configured to detect a pattern image on the image bearing member.

Abstract: An image forming apparatus includes an image forming unit configured to form an image on a sheet based on image forming condition, a reader configured to convey the sheet and read a test image on the sheet while the sheet is conveyed, and a controller configured to control the image forming unit to form the image and the test image on a same sheet, control the reader to read the test image on the same sheet, and generate the image forming condition for adjusting a density of an image to be formed by the image forming unit, based on a reading result of the test image by the reader.

Abstract: An image forming apparatus includes: a developing roller; a photosensitive drum; a first measurement device that measures a blank portion current in a first line on the photosensitive drum which extends in a scanning direction of the photosensitive drum and on which no toner patch is formed; a second measurement device that measures a measuring development current in a second line on the photosensitive drum which extends in the scanning direction of the photosensitive drum and on which a toner patch is formed; and a control device that functions as a patch setter and a first calculator. The patch setter sets a patch width of the toner patch in the scanning direction of the photosensitive drum. The first calculator calculates an actual development current based on a developable width of the photosensitive drum in the scanning direction, the patch width, the blank portion current, and the measuring development current.

Abstract: An image forming apparatus includes: an image forming unit configured to form an image on an image bearing member based on an image forming condition, an optical sensor including: a light emitter configured to irradiate the image bearing member with light based on a supplied current; and a light receiver configured to receive reflected light of the light emitted from the light emitter; a temperature detector configured to detect a temperature of the optical sensor; and a controller configured to: control the image forming unit to form a detection image on the image bearing member; control the optical sensor to detect reflected light from the detection image; and adjust the image forming condition based on a result of detecting the detection image by the optical sensor. The controller is configured to control the light emitter to emit light; and generate a correction condition.

Abstract: An imaging system includes a toner imaging device to form a toner image, a toner image conveying device to convey the toner image, a medium conveying device to convey a medium, and a toner image recording device to record the toner image conveyed by the toner image conveying device on the medium conveyed by the medium conveying device. Additionally, the imaging system includes a control device to determine a stop state including at least one of a state where a recording check toner image is recorded on the medium, a state where a conveyance check toner image is positioned on the toner image conveying device, and a state where a formation check toner image is positioned on the toner imaging device. During the stop state, the control device stops a formation of the toner image that is performed by the toner imaging device, stops a conveyance of the toner image that is performed by the toner image conveying device, and stops a conveyance of the medium that is performed by the medium conveying device.

Abstract: An image forming apparatus includes a first sensor configured to measure measurement images on a first photoreceptor, a second sensor configured to measure measurement images on an intermediate transfer member, and a controller. The controller controls a first image forming unit to form first measurement images, wherein the first measurement images are formed along a rotation direction of the first photoreceptor, and controls the first sensor to measure the first measurement images on the first photoreceptor. The controller further controls the first image forming unit and a second image forming unit to form a plurality of measurement images while a rotation speed of the first photoreceptor is being controlled based on a measurement result of the first sensor, wherein the plurality of measurement images are formed along the predetermined direction of the intermediate transfer member.

Abstract: An image forming apparatus includes an image bearing member, an image forming portion, an endless belt, a plurality of stretching rollers including an inner roller, an outer roller, a position changing mechanism capable of changing a position of the inner roller to a first position and a second position positioned downstream of the first position with respect to a rotational direction of the endless belt, a feeding member, a feeding member driving portion, and a controller. A feeding start timing of a recording material by the feeding member depends on the position of the inner roller during transfer of a toner image onto the recording material.

Abstract: Examples of methods are described herein. In some examples, a method includes calculating a first cost function measure based on band defects in an image. In some examples, the method also includes calculating a second cost function measure based on the band defects and a synthetic band. In some examples, the method further includes detecting a missing band based on a comparison of the first cost function measure and the second cost function measure.

Abstract: In an image forming apparatus a toner cartridge includes a toner memory storing toner identification information. The toner cartridge is detachably attachable to a drum cartridge. The drum cartridge includes a drum memory storing drum identification information. The drum cartridge is detachably attached to the main-body casing.

Abstract: Downtime relating to formation and detection of a detection image is reduced. An image forming apparatus includes a controller configured to calculate a first conversion unit to convert a gradation of input image data so that density output for the input image data becomes a first density output characteristic based on a first detection result of the detection image detected by a density sensor in a first mode. The controller generates a second conversion unit to convert the gradation of the input image data so that the density output for the input image data becomes a second density output characteristic in a second mode based on the detection result in the first mode and correction information, and further updates the correction information based on a second detection result of the detection image detected by the density sensor in the second mode and the first detection result.

Abstract: In the subject architecture flexible binary arithmetic coding system, coding circuitry of an electronic device may receive video data that is to be coded (e.g., to be encoded or decoded) by binary arithmetic coding. The coding circuitry may also compute at least one of a least probable symbol (LPS) range or a most probable symbol (MPS) range based on a multiplication operation (e.g., without performing a table look-up operation). The coding circuitry may perform binary arithmetic coding on the video data using the at least one of the LPS range or the MPS range. The computation of the LPS range and/or the MPS range using the multiplication operation may have a lower computational cost than using a table look-up operation.

Abstract: According to one embodiment, an image forming apparatus includes a plurality of parts, an acquisition unit, and a control unit. The plurality of parts are used in the image forming process and are replaced according to the degree of use. The acquisition unit acquires, for each of the parts, use-related information that is information indicating the degree of use of the plurality of parts. The control unit determines the replacement timing of the part using the plurality of pieces of use-related information acquired by the acquisition unit and the determination condition regarding the replacement timing of the part.

Abstract: A controller is configured to, when forming an image on one sheet, in a case where a length of one sheet in a conveyance direction is larger than a first length, drive a moving mechanism to move a plurality of developing rollers from a separation position to a contact position, temporarily stop driving of the moving mechanism, and then, at a first timing, again drive the moving mechanism to move the plurality of developing rollers from the contact position to the separation position; and in a case where the length of the one sheet in the conveyance direction is smaller than or equal to the first length, drive the moving mechanism to move the plurality of developing rollers from the separation position to the contact position and then to move the plurality of developing rollers from the contact position to the separation position without stopping driving of the moving mechanism.

Abstract: Provided is an image forming apparatus having a simple configuration capable of measuring a toner current included in a developing current and accurately calculating a toner charge amount based on the measurement result. The developing device has a developer carrier that carries a two-component developer including a magnetic carrier and toner. The density detecting device detects the density of the toner image. The current detecting unit detects a DC component of a developing current that flows when a developing voltage is applied to the developer carrier. The control unit, in a state in which the image carrier is rotated at two or more different linear speeds during non-image formation, forms the same reference image on the image carrier by the developing device, and estimates the toner charge amount based on the developing current when the reference image is formed and the density of the reference image.

Abstract: An image forming apparatus includes an image forming portion, a rotatable intermediary transfer belt, a plurality of stretching rollers, an outer roller, a moving mechanism, and a controller. In a case that a basis weight of a first recording material is a first basis weight and a basis weight of a second recording material is a second basis weight greater than the first basis weight, a position of the inner roller is a second position when the toner image is transferred onto the second recording material, and in a case that the basis weight of the first recording material and the basis weight of the second recording material are the second basis weight, the position of the inner roller is a first position when the toner image is transferred onto the second recording material.

Abstract: According to one embodiment, an image forming apparatus includes an image forming unit, a sensor, and a control unit. The image forming unit forms a pattern constituted by a plurality of straight lines intersecting each other on a sheet or a transfer belt. The sensor detects the pattern formed on the sheet or the transfer belt. The control unit adjusts a writing position in a main scanning direction on the basis of the pattern detected by the sensor.

Abstract: An image forming apparatus including a belt, a plurality of color information detectors, and a hardware processor. The belt is a belt on which images of a plurality of colors are formed to be laid on each other by a plurality of image formers that form the images of color components different from each other, the belt being colorless and transparent and having a transparency. The plurality of color information detectors are arranged on a front surface side and a back surface side of the belt, and detect, from the front and back surface sides, color information about a pattern image including two layers formed on the belt by two image formers among the plurality of image formers. The hardware processor calculates a color correction amount of an image formed by the two image formers based on detection results by the color information detectors.

Abstract: An image forming apparatus includes a first sensor configured to measure measurement images on a first photoreceptor, a second sensor configured to measure measurement images on an intermediate transfer member, and a controller. The controller controls a first image forming unit to form first measurement images, wherein the first measurement images are formed along a rotation direction of the first photoreceptor, and controls the first sensor to measure the first measurement images on the first photoreceptor. The controller further controls the first image forming unit and a second image forming unit to form a plurality of measurement images while a rotation speed of the first photoreceptor is being controlled based on a measurement result of the first sensor, wherein the plurality of measurement images are formed along the predetermined direction of the intermediate transfer member.

Abstract: Provided is an image forming system that can prevent unnecessary down time and spoiled paper from being caused, thereby improving productivity. The image forming system includes an image forming portion, a detecting portion, and a controlling portion. When an abnormality has been detected by the detecting portion, when a reading portion for reading an image formed on a recording medium by the printing operation of the image forming portion is provided, the controlling portion causes the reading portion to function to continue the printing operation, and at the detection of the abnormality on the basis of the read image, stops the printing operation to cause a notifying portion to perform notification related to the abnormality, and when the reading portion is not provided, the controlling portion stops the printing operation to cause the notifying portion to perform the notification related to the detected abnormality.

Abstract: An image forming apparatus includes an image bearing member, a transfer member, a voltage source, a sensor configured to detect a current value or a voltage value, an image detecting portion, and a controller capable of executing an operation in a mode for setting a transfer voltage to be applied to the transfer member, on the basis of a result of detection of a test chart formed on a test recording material. The controller sets the transfer voltage on the basis of a first detection result acquired by the sensor under application of a voltage to the transfer member when the recording material is absent in the transfer portion and a second detection result acquired by the sensor under application of the test voltages to the transfer member when the test recording material is present in said transfer portion during the operation in the mode.

Abstract: A driving device for driving a driven member includes a driving source; a driving gear fixed to a rotation shaft of the driving source; at least one gear for transmitting rotational motion of the driving gear to the driven member; a rotation detection gear engaged with the at least one gear; a detector for detecting rotation of the rotation detection gear; and a controller for detecting an angular speed and a rotational phase of the rotation detection gear on the basis of information from the detector and for controlling the rotational speed of the driving source such that a rotation period of the rotation detection gear is a non-integer multiple of a rotation period of the driving gear.

Abstract: A charging member which is driven so that the surface of the charging member has a speed difference from the surface of an image bearing member. In a cleaning operation for cleaning the charging member by transferring toner adhering to the surface of the charging member from the charging member to the image bearing member and collecting the transferred toner with a developing member, a first charging voltage forming a potential difference between the charging member and the image bearing member is applied to the charging member, and then a second charging voltage having the same polarity as that of the first charging voltage and an absolute value greater than that of the first charging voltage is applied. The potential difference is in a direction in which electrostatic force directed from the charging member to the image bearing member acts on the toner charged to normal polarity.

Abstract: In an image forming apparatus, an exposure device irradiates a real latent image line position with scanning light in a primary scanning direction and thereby forms an electrostatic latent image at the real latent image line position, and irradiates two real latent image line positions with scanning light in a primary scanning direction and thereby forms an electrostatic latent image at an imaginary latent image line position between the two real latent image line positions. A controller adjusts light emitting time per dot in the exposure device for the real latent image line positions irradiated to form the electrostatic latent image at the imaginary latent image line position, on the basis of a development potential difference corresponding to a development bias voltage of the development device that has been adjusted in calibration and a surface potential of an exposure area on a photoconductor drum.