An image forming apparatus includes a developing roller configured to develop an electrostatic latent image on a photosensitive drum to form a toner image; a belt onto which the toner image is transferred; a detection unit configured to detect a density of an image for detection formed on the belt; and a controller configured to perform hue adjustment based on a detection result of the detection unit. The image forming apparatus performs image formation in a second mode using a color gamut different from a color gamut in a first mode, and the controller obtains a lookup table, which indicates a correlation between image data to be used and input image data in the second mode, based on the detection result in the first mode and a correlation of density between the first mode and the second mode.

An image forming apparatus includes an image bearer, an image forming section, an image density difference detector, and control circuitry. The image forming section is configured to form a gradation image pattern on a surface of the image bearer. The gradation image pattern includes gradation images having different image densities stepwise in a sub-scanning direction. The image density difference detector is configured to detect image density differences in a main scanning direction of the gradation images. The control circuitry is configured to execute an image density difference correction mode that corrects the image density differences in the main scanning direction based on detection results detected by the image density difference detector.

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 LED, a second LED, a first PD, and a second PD. The first LED and the second LED irradiate an optical-axis center point of an intermediate transfer belt. The first PD is arranged at a position at which an optical axis of specularly reflected light of light emitted from the second LED and an optical axis along which specularly reflected light of light emitted from the first LED is received form an angle . The second PD is arranged at a position at which the optical axis of the specularly reflected light of the light emitted from the second LED and an optical axis along which diffused reflected light of the light emitted from the second LED is received.

An image forming apparatus includes a conveyance guide, a measurement unit, an opposing member, and a holding member. The conveyance guide has an opening and forms a conveyance path through which a sheet with an image formed on the sheet is conveyed. The measurement unit measures, through the opening, a color of the image on the sheet being conveyed through the conveyance path. The opposing member opposes the measurement unit at a measurement position of the measurement unit. The holding member holds the opposing member so that the opposing member is movable between a first position where the opposing member presses the sheet against the opening and a second position where the opposing member is separated from the opening as compared with the first position. The holding member includes an abutment portion that abuts against the conveyance guide in a state where the opposing member is at the first position.

An image forming apparatus includes an image forming device to form an image on an image bearer based on a prescribed image-forming condition, and circuitry to change the prescribed image-forming condition and correct image-density unevenness in an image-width direction orthogonal to an image conveyance direction of the image bearer. In the image forming apparatus, the circuitry calculates a corrective value of the prescribed image-forming condition for each one of positions in the image-width direction, based on unevenness-in-density corrective values for the multiple positions in the image-width direction and relational values indicating a relation between the multiple unevenness-in-density corrective values and the corrective value of the prescribed image-forming condition, and the circuitry corrects the image-density unevenness in the image-width direction based on the corrective value of the prescribed image-forming condition. In the image forming apparatus, the multiple relational values correspond to portions in the image-width direction.

A specification part of an information processing device specifies, by using image data for a correction chart defining a plurality of patch regions having different color values, a target characteristic indicating a relation between the color value and a first colorimetric value of a first patch image as a laminated image of a special color image and a colored image that correspond to each of the patch regions formed by the device through the 2-path printing. A generation part of the device generates a correction table for correcting the color value so that a measured characteristic comes close to the target characteristic, the measured characteristic indicating a relation between the color value and a second colorimetric value of a second patch image as the laminated image corresponding to each of the patch regions formed by the device through the 1-path printing using the image data for a correction chart.

In accordance with an embodiment, a print head includes a first light emitting element line and a second light emitting element line. The first light emitting element line and the second light emitting element line each include a plurality of light emitting elements that emit light on the basis of image data. The plurality of light emitting elements of the second light emitting element line are arranged deviated from the plurality of light emitting elements of the first light emitting element line by a certain interval in a main scanning direction.

An image forming apparatus includes: multiple intermediate-transfer-member density sensors that are disposed in the axial direction of an intermediate transfer member and that detect corresponding densities of a developer image having been subjected to first transfer onto the intermediate transfer member; and a processor configured to: in response to occurrence of a variation of density on a recording medium, if a relationship between the highest density value and the lowest density value among the density values detected by the respective intermediate-transfer-member density sensors indicates a first density state, output information indicating that the variation of density is caused in a process of or after a second-transfer process in which the developer image having been subjected to first transfer onto the intermediate transfer member is transferred onto the recording medium; and if the relationship indicates a second density state opposite to the first density state, output information indicating that the variation of density is caused in a process before the second-transfer process.

An image forming apparatus includes: multiple image carriers holding developers; multiple potential detectors that are mounted in a first scanning direction on each of the image carriers and detect surface potentials of the image carriers; an intermediate transfer body to which the developers held by the image carriers are transferred; and multiple density detectors that are mounted in the first scanning direction of the intermediate transfer body and detect densities of the developers transferred to the intermediate transfer body. A subset of the potential detectors is mounted at a location corresponding to a location where the density detectors are mounted and a subset of the potential detectors is mounted at a location that is common to the image carriers.

An image forming apparatus includes a transfer member which transfers a toner image formed on an image bearing member to a transfer material; a transfer bias application unit which applies bias to the transfer member; a controller which executes a mode for making a first bias applied to a first predetermined area arranged at a leading edge of a transfer material with respect to a conveying direction of the transfer material to be less than a second bias applied to a second predetermined area arranged in a central area of the transfer material; and an obtaining portion which obtains image information of an image formed in each area obtained by dividing an area corresponding to the leading edge area into plural pieces in the width direction, wherein the controller controls the first bias based on image information obtained by the obtaining portion at the time of the mode.