Abstract: An image forming apparatus includes an image carrier, a rotation-position detector, a development device, a transfer unit, a density sensor, and an image-forming-condition determination unit. The density sensor senses a density of a toner image on a transfer body. The image-forming-condition determination unit forms an image pattern, acquires periodical density variation information sensed by the density sensor and detection information of the rotation-position detector, and determines an image forming condition based on the periodical density variation information and the detection information acquired. The image carrier and the transfer body are different in linear velocity in an image formation in which the toner image is transferred to a recording medium.

Abstract: An image forming apparatus includes an image density detector, an image forming device, a rotator, an image density controller, and a timing correction data obtainer. The image density detector detects a toner density of an image formed on an image bearing member. An image forming device forms the image using a density adjustable element that adjusts the density of the image. The rotator forms an image pattern while the density adjustable element is changed, and a density thereof is detected by the image density detector. The image density controller controls the image forming device using a density correction data for the density adjustable element corresponding to a rotational period of the rotator. The timing correction data obtainer obtains timing correction data for correction of driving timing of the image forming device based on a change in the density of the image pattern detected by the image density detector.

Abstract: An image forming apparatus includes an image forming unit including rotary members to form a toner image corresponding to image data, in which the image forming unit forms a toner pattern for detecting image density fluctuation; and an image forming condition determination controller to perform image forming processing to ultimately transfer the toner image onto a recording medium. In the image forming apparatus, the controller measures a periodic image density fluctuation occurring in a rotation cycle of the rotary members based on a detection result of a toner pattern; performs image forming condition determination processing to determine an image forming condition to reduce the image density fluctuation based on measured image density fluctuation data; and determines whether or not the image density fluctuation data measured multiple times satisfies a predetermined control termination condition.

Abstract: A printer determines, in a process control, a reference exposure amount. A charging unit charges a surface of a photosensitive element to a target potential. After an exposure target area on the charged surface of the photosensitive element is exposed to a high adjustment exposure that corresponds to a high-exposure amount area, a control unit determines the reference exposure amount based on the target potential and a detected residual potential that is a result detected by a potential detecting unit as a potential of the target exposure area on the photosensitive element after being exposed to the high adjustment exposure.

Abstract: An image forming apparatus for performing an image forming operation is disclosed that includes an image carrier on which a toner image is formed, an intermediate transfer member configured to transfer the toner image to a recording medium, the intermediate transfer member having a toner image forming area including an output image forming area and a non-output image forming area located outside of the output image forming area, the toner image forming area being wider than the output image forming area, and a detecting part configured to measure a physical quantity regarding an image quality of a first reference image formed in the output image forming area and a second reference image formed in the non-output image forming area.

Abstract: A device for determining an end of life of an organic photoreceptor includes a potential detecting unit that detects a residual potential of the organic photoreceptor, a temperature detecting unit that detects temperature of the organic photoreceptor in either one of a direct manner and an indirect manner, and a life determining unit that determines the end of life of the organic photoreceptor based on the residual potential detected by the potential detecting unit and the temperature detected by the temperature detecting unit.

Abstract: An image forming apparatus includes a latent image carrier, a developing unit to develop a latent image on the image carrier with developer including toner and carrier, a developer bearing member, a first detector to detect a toner adhesion amount per unit area of a toner image developed by the developing unit, a second detector to detect humidity, and a controller to calculate an index indicating toner chargeability of the carrier based on detection results of the toner adhesion amount obtained by the first detector and perform a given control process based on calculation results thereof and including a data storage unit to store an algorithm to correct the index to a specific value according to a specific humidity, based on detection results of the humidity obtained by the second detector. The controller corrects the index obtained based on the amount of toner adhesion based on the algorithm.

Abstract: An image forming apparatus forms high precision full color image by correcting the adhesion quantity of an image visualizing agent and a position shift of a visible image while performing printing process. The image forming apparatus includes an intermediate transfer unit; plural photoconductors; plural charging units; plural exposure units; plural developing units; plural first transferring units; and plural second transferring units. The intermediate transfer unit has a correction pattern image formed in a region outside a predetermined maximum document region in a direction perpendicular to the moving direction. A detector in the intermediate transfer unit detects the correction pattern image. A correction controller performs correcting, based on detection results of the detector, setting values of one or more of the charging units, the exposure units, and the developing units when a region corresponding to an interval between the visible images passes a position beneath one of the units.

Abstract: An image formation apparatus is disclosed. The image formation apparatus includes a transfer effectiveness detector that further includes a computing unit for converting a sensor output voltage into a toner adhesion amount, and a transfer effectiveness detecting unit for obtaining transfer effectiveness by comparing a toner adhesion amount Td on a photo conductor with a toner adhesion amount Tb on a middle transfer object. Here, the toner adhesion amount Td is obtained by the computing unit converting an output of a photo conductor image detection unit, and the toner adhesion amount Tb is obtained by the computing unit converting an output of a middle transfer object image detection unit. When the transfer effectiveness detection unit determines that an abnormality is present in the transfer, whether the abnormality is due to decreased development capacity or due to decreased transfer effectiveness can be determined.

Abstract: A device for determining an end of life of an organic photoreceptor includes a potential detecting unit that detects a residual potential of the organic photoreceptor, a temperature detecting unit that detects temperature of the organic photoreceptor in either one of a direct manner and an indirect manner, and a life determining unit that determines the end of life of the organic photoreceptor based on the residual potential detected by the potential detecting unit and the temperature detected by the temperature detecting unit.

Abstract: An image forming apparatus includes a latent image carrier, a developing unit to develop a latent image on the image carrier with developer including toner and carrier, a developer bearing member, a first detector to detect a toner adhesion amount per unit area of a toner image developed by the developing unit, a second detector to detect humidity, and a controller to calculate an index indicating toner chargeability of the carrier based on detection results of the toner adhesion amount obtained by the first detector and perform a given control process based on calculation results thereof and including a data storage unit to store an algorithm to correct the index to a specific value according to a specific humidity, based on detection results of the humidity obtained by the second detector. The controller corrects the index obtained based on the amount of toner adhesion based on the algorithm.

Abstract: A printer determines, in a process control, a reference exposure amount. A charging unit charges a surface of a photosensitive element to a target potential. After an exposure target area on the charged surface of the photosensitive element is exposed to a high adjustment exposure that corresponds to a high-exposure amount area, a control unit determines the reference exposure amount based on the target potential and a detected residual potential that is a result detected by a potential detecting unit as a potential of the target exposure area on the photosensitive element after being exposed to the high adjustment exposure.

Abstract: An image forming apparatus for performing an image forming operation is disclosed that includes an image carrier on which a toner image is formed, an intermediate transfer member configured to transfer the toner image to a recording medium, the intermediate transfer member having a toner image forming area including an output image forming area and a non-output image forming area located outside of the output image forming area, the toner image forming area being wider than the output image forming area, and a detecting part configured to measure a physical quantity regarding an image quality of a first reference image formed in the output image forming area and a second reference image formed in the non-output image forming area.

Abstract: An image formation apparatus is disclosed. The image formation apparatus includes a transfer effectiveness detector that further includes a computing unit for converting a sensor output voltage into a toner adhesion amount, and a transfer effectiveness detecting unit for obtaining transfer effectiveness by comparing a toner adhesion amount Td on a photo conductor with a toner adhesion amount Tb on a middle transfer object. Here, the toner adhesion amount Td is obtained by the computing unit converting an output of a photo conductor image detection unit, and the toner adhesion amount Tb is obtained by the computing unit converting an output of a middle transfer object image detection unit. When the transfer effectiveness detection unit determines that an abnormality is present in the transfer, whether the abnormality is due to decreased development capacity or due to decreased transfer effectiveness can be determined.

Abstract: An image forming apparatus is disclosed that is able to form a full color image with high precision by correcting the adhesion quantity of an image visualizing agent and a position shift of a visible image while continuing to perform a printing process. The image forming apparatus includes an intermediate transfer unit; plural photoconductors; plural charging units; plural exposure units; plural developing units; plural first transferring units; and plural second transferring units. The intermediate transfer unit has a correction pattern image formed in a region outside of a predetermined maximum document region of the intermediate transfer unit in a direction perpendicular to the moving direction. A detector is provided in the intermediate transfer unit for detecting the correction pattern image.

Abstract: An image detector has an I/V converter for converting, into a voltage output., a current output as a result of a photoelectric element arranged in a traveling direction of an intermediate transfer belt having received light reflected from the intermediate transfer belt and light reflected from toner images formed on the intermediate transfer belt; a peak-hold unit for holding an output voltage into which the light reflected from the intermediate transfer belt has been converted by the I/V converter; and a computation unit for detecting a difference between the output voltage of the peak-hold unit and an output voltage into which the light reflected from the toner images of respective colors has been converted by the I/V converter.

Abstract: An image detector has an I/V converter for converting, into a voltage output., a current output as a result of a photoelectric element arranged in a traveling direction of an intermediate transfer belt having received light reflected from the intermediate transfer belt and light reflected from toner images formed on the intermediate transfer belt; a peak-hold unit for holding an output voltage into which the light reflected from the intermediate transfer belt has been converted by the I/V converter; and a computation unit for detecting a difference between the output voltage of the peak-hold unit and an output voltage into which the light reflected from the toner images of respective colors has been converted by the I/V converter.

Abstract: A print control method of an electrophotograph in an image formation apparatus including at least a photoconductor, a charger, a light exposure unit, and a developing device for forming a background area and an image area on the photoconductor using the charger and the light exposure unit and detecting a potential of the image area after transfer and controlling a developing electric field, thereby printing an electrophotograph, includes lowering the percentage of toner covering the image area on the photoconductor when the potential is detected.

Abstract: An image forming apparatus restricts disturbance of a potential patch in the case where a potential sensor for detecting the potential patch is provided downstream of a developing device of a multiple developing roller type so as to enable stable reproduction of a high quality image for a long period. The apparatus includes a potential sensor provided downstream in the moving direction of the image carrier relative to the developing device for detecting a potential on the image carrier, and a controller for setting the developing bias to a value restricting disturbance of a potential portion as an object for potential detection by the potential sensor by the developer when the potential portion passes across the developing device.

Abstract: In an electrophotographic apparatus, regions having at least three different potential levels Vc, Vw, and Vr are formed on a photosensitive member by using an exposing device, and developing processes respectively using colored particles of different kinds are performed by normal development and reversal development on two potential levels Vc and Vr excluding the intermediate potential level Vw. The apparatus has an auxiliary exposing unit for forming a fringe development preventing potential in an edge of an image forming region in order to prevent fringe development from occurring. The auxiliary exposing unit sets an auxiliary exposure amount by performing pulse-width modulation on a laser driver.