Abstract: A light receiving portion is configured to receive light that varies with time while a mark formed on an object moves across a detection area. The position of the mark on the object is determined based on comparison of a time-varying level of the light with at least one threshold during movement of the mark on the object across the detection area. The determined position of the mark is corrected by a correction value into a corrected mark position. The correction value is set to a higher value, if the time-varying light level exceeds the threshold or falls below the threshold with a smaller slope while the mark moves across the detection area. An image forming position is adjusted based on the corrected mark position.

Abstract: An image forming apparatus includes: a conveyance member; a detection unit which outputs a detection signal according to a mark for image formation condition correction; an image forming unit which forms a print image and the mark; and a change unit which changes at least one of a printing reference position and a mark reference position such that an offset amount between the printing reference position and the mark reference position becomes larger as an angle difference between a sub-scanning direction and a conveyance direction of the conveyance member is larger, wherein the printing reference position is a basis of determining a formation position of the print image in a main scanning direction and the mark reference position is a basis of determining at least one of a formation position and a size of the mark in the main scanning direction.

Abstract: An image forming apparatus may include a conveyor member, an optical sensor, a drive portion, and a controller. The drive portion performs a rotation for detection to rotate the conveyor member for the mark detection and a rotation for nondetection to rotate the conveyor member for a purpose other than the mark detection. The controller obtains an amount of reflected light received by the optical sensor to determine an adjustment value of sensitivity of the optical sensor based on the amount of received reflected light while the rotation for nondetection is performed. The controller also detects the mark with the sensitivity adjusted based on the determined adjustment value while the rotation for detection is performed.

Abstract: In an image forming apparatus, developer remaining on a photosensitive member as transfer residual developer is caught temporarily by a catching portion. In a collecting process, the transfer residual developer caught by the catching portion is returned to the photosensitive member, the transfer residual developer then is transferred onto a conveyor member, and the transfer residual developer is collected by a collecting portion. In the collecting process, the presence or absence or an amount of the transfer residual developer transferred onto the conveyor member is measured.

Abstract: An image forming apparatus is provided. The image forming apparatus includes an image forming unit configured to form a mark, a conveyance member configured, to convey the mark, a sensor configured to read the mark conveyed by the conveyance member, a measurement unit configured to measure a moving time period between a time when the image forming unit forms the mark and a time when the mark conveyed by the conveyance member is read by the sensor, and a determination unit configured to determine whether a traveling speed of the conveyance member is appropriate based on the moving time period measured by the measurement unit.

Abstract: An image forming apparatus including an image carrier, a plurality of forming devices, a detecting device configured to perform a steady-deviation detection for detecting steady positional deviation and a varying-deviation detection for detecting varying positional deviation having a cycle, and a correcting device configured to perform a steady-deviation correction for correcting the steady positional deviation and a varying-deviation correction for correcting the varying positional deviation. The detecting device forms, during the steady-deviation detection, a steady-deviation detection pattern in a state where the varying deviation correction is selectively disabled. The steady-deviation detection pattern has a plurality of measuring points arranged in a longitudinal direction. The detecting device, during the steady-deviation detection, measures positional deviation amount at each measuring point, and detects the steady positional deviation based on the measurement result.

Abstract: In an image-forming device includes an image-forming unit, a first conveying unit, a first changing unit, and a second changing unit. The image-forming unit includes a rotatable mirror, a light-emitting unit, a photosensitive drum, a developing unit, a transferring unit. An electrostatic latent image composed of a plurality of line electrostatic latent images extending in a main scanning direction over a first length is formed on the photosensitive drum. The first conveying unit conveys a recording medium to the transferring position in a sub-scanning direction orthogonal to the main scanning direction. The first changing unit changes a rotating speed of the rotatable mirror to change the first length. The second changing unit proportionally changes a conveying speed of the first conveying unit in accordance with the change of the rotating speed of the rotatable mirror.

Abstract: An image forming apparatus includes an automatic acquiring unit which forms a mark for detecting at least one of positional deviation and density deviation and acquire a degree of deviation by measuring the mark, a manual acquiring unit which receives a user input to acquire a correction value; an image forming unit which forms an image based on an actual correction value determined by an automatic correction value specified based on the degree of deviation and a manual correction value which is the correction value acquired by the manual acquiring unit, and a changing unit which executes at least one of a first changing process of applying a weight to at least one of the automatic correction value and the manual correction value and the second changing process of changing at least one of the automatic correction value and the manual correction value into a past correction value.

Abstract: An image forming apparatus is provided. The image forming apparatus includes: a manual acquiring unit which is configured to receive a user input to acquire a correction value; an image forming unit which is configured to form an image while adjusting at least one of positional deviation and density deviation of the image based on the correction value; and a changing unit which is configured to execute at least one of a first changing process of changing a permissible range of a correction value for positional deviation according to a status of a factor causing a change in a position of an image, and a second changing process of changing a permissible range of a correction value for density deviation according to a status of a factor causing a change in a density of an image.

Abstract: An image forming apparatus includes an automatic acquiring unit which is configured to form a mark for detecting at least one of positional deviation and density deviation and acquire an amount of deviation by measuring the mark, an image forming unit which is configured to form an image while adjusting at least one of positional deviation and density deviation based on a correction value specified by the amount of deviation, and an output unit which is configured to execute at least one of a pattern printing process and a notifying process when an amount of deviation within a permissible range is not acquired by the automatic acquiring unit. The pattern printing process includes printing a pattern image for specifying a correction value on a recording sheet. The notifying process includes making notification for prompting execution of the pattern printing process.

Abstract: A controlling section controls an image forming section to form a calibration pattern on an object. The calibration pattern includes a plurality of first patterns and a plurality of second patterns. Each of the first patterns includes at least one pair of marks. Each of the at least one pair of marks has different colors and overlaps with each other in a first direction. The first patterns have different degrees of overlapping from each other. Each of the second patterns is formed between one of the first patterns and another one of the first patterns in the moving direction. The detecting section detects the first and second patterns formed on the object. The correcting section corrects the image forming position in the first direction based on detection results of the first patterns, and corrects the image forming position in a second direction based on detection results of the second patterns.

Abstract: An image forming apparatus for preventing sheet jams and displacement of image formation when forming images on both front and rear sides is provided. The apparatus includes first and second width regulation mechanisms, a reverse transport mechanism and a link mechanism. The first width regulation mechanism is provided within a sheet holding chamber, and is movable with respect to a center of an image formation range of an image forming unit. The reverse transport mechanism is configured to turn the sheet from a first side to a second side upon the first side passing through the image forming unit. The second width regulation mechanism, provided within the reverse transport mechanism, is movable in the width direction. The link mechanism is provided between the first and second width regulation mechanisms for changing a position of the second width regulation mechanism in association with position change of the first width regulation mechanism.

Abstract: An image forming apparatus includes a carrier, a forming device forming a mark on the carrier, a sensor, a determiner, a changer, an evaluator and a controller. The sensor includes a light emitting device that emits light toward the carrier and the light receiving device that receives light reflected from the carrier or the mark and outputs a light reception signal corresponding to the received light quantity. The determiner determines a position of the mark based on the light reception signal. The changer changes sensor sensitivity by changing a quantity of light from the light emitting device or sensitivity of the light receiving device. The evaluator obtains the light reception signals multiple times and evaluates a degree of closeness between an average level of the light reception signals and a target level. The controller controls the changer to change the sensor sensitivity of the sensor according to an evaluation result.

Abstract: An image-forming device includes an image-forming unit, a sensor, a screening unit, an excluding unit, and a determining unit. The image-forming unit forms a plurality of marks on an object. The sensor detects a light reflected on the object, the reflected light including a plurality of waveforms. The screening unit screens the plurality of waveforms into a plurality of mark waveforms corresponding to the plurality of marks respectively and a plurality of noise waveforms other than the plurality of mark waveforms. The excluding unit excludes a mark waveform adjacent to the noise waveform from the plurality of mark waveforms. The determining unit determines a position of each mark based on the plurality of mark waveforms from which the mark waveform adjacent to the noise waveform is excluded.

Abstract: An image forming apparatus includes an image forming section, a controlling section, a detecting section, and a correcting section. The image forming section forms an image on an object. The controlling section controls the image forming section to form a calibration pattern on the object. The calibration pattern includes a plurality of marks in a first group and a plurality of marks in a second group. The plurality of marks in each of the first group and the second group is arranged in a first direction over a predetermined range. The plurality of marks in each of the first group and the second group includes first marks and second marks. The first mark in the first group corresponds to the second mark in the second group in a second direction different from the first direction in at least part of the predetermined range. The first mark in the second group corresponds to the second mark in the first group in the second direction in at least part of the predetermined range.

Abstract: A controlling section controls an image forming section to form a calibration pattern on an object. The calibration pattern includes a plurality of marks in first and second groups. The marks in the second group are formed at a different position in the second direction from the marks in the first group. The marks in each of the first and second groups are arranged in the first direction over a predetermined range on the object. Each mark has shape and color. The detecting section detects the calibration pattern formed on the object, thereby obtaining detection results. The correcting section corrects, based on the detection results, an image forming position at which the image forming section forms an image. The marks belonging to different groups and having a same color are formed at different positions with respect to the first direction in at least part of the predetermined range.

Abstract: An image forming apparatus is provided. The image forming apparatus includes: a forming unit configured to form an image on a relatively moving object, the image including a mark; a first detection unit configured to detect the mark formed by the forming unit so as to obtain a first detection result; a correction unit configured to execute a correction process in which an image forming condition of the image forming unit is changed based on the first detection result; a setting unit configured to set the correction process not to be executed when a value related to a correction accuracy of the correction unit is lower than a reference value; and a control unit configured to control the correction process based on the setting by the setting unit.

Abstract: An image forming device includes an image forming section, a CPU and memory storing executable instructions that, when executed by the CPU, cause the image forming device to provide functions including a data acquisition section, a mismatch correction section and a control section. The data acquisition section is configured to acquire a variation in factor that causes a mismatch of a parameter. The control section is configured to estimate an amount of mismatch of the parameter based on the variation and to send a request for measuring the amount of mismatch to the mismatch correction section when the estimated amount is equal to or larger than a reference value. The control section is also configured to alter at least one of calculation factors used for estimating the amount of mismatch and the reference value according to the measured amount.

Abstract: An image forming apparatus is provided. The image forming apparatus includes: a formation unit configured to form marks for measurement of a positional deviation on a relatively moving object; an optical sensor having a detection region on the object, and configured to output a light receiving signal depending on existence of the marks within the detection region; a removing unit configured to perform a noise removing process, including a first noise removing process and a second noise removing process which use different removing methods for removing noises included in the light receiving signal so as to generate a noise removing result; and a measurement unit configured to measure a positional deviation amount of image formed by the formation unit, based on the noise removing result.

Abstract: An image forming apparatus comprising: a formation unit; a control unit configured to control the formation unit to form a first batch and a second batch; a detection unit configured to detect detection values for marks in relation with position information of the respective marks in the first direction; a determination unit configured to determine whether each of the first and second batches are normal or abnormal based on the detection values; a modification unit configured to modify the detection value of a mark belonging to one of the first and second batches that has been determined to be abnormal by the determination unit, based on the detection value of a corresponding mark which belongs to an other of the first and second batches; and a correction unit configured to correct an image forming position of the formation unit based on the detection values modified by the modification unit.