A laser scanning unit includes a light source portion, a scanning portion, a first correction portion, and a second correction portion. The light source portion outputs a light beam. The scanning portion scans the light beam to form an electrostatic latent image in an image forming portion. The first correction portion applies an external mechanical force to an optical element located in a path of the light beam to correct inclination of a scan line of the light beam. The second correction portion controls the light source portion to correct distortion of the scan line of the light beam.

An image forming apparatus, configured to operate in first and second modes of which color gamut is different from each other, includes an exposure unit configured to expose a photosensitive drum; a developing roller configured to form a toner image; a detection unit configured to detect density of the toner image transferred to an intermediate transfer member; and a controller configured to adjust the density based on a value of input image data. A dithering process for the controller's controlling of the exposure unit is different depending on whether the operation is in the first mode or the second mode, and in at least a part of the input image data, the density of the toner image formed by the dithering process in the first mode is higher than the density of the toner image formed by the dithering process in the second mode.

There is provided an image forming system including an image forming apparatus including a hardware processor that forms an image on a recording material, and the image forming system includes: a first detector that detects recording material information on the recording material; a recording material storage that stores the recording material; and a controller that specifies one type of the recording material from type candidates of the recording material based on an execution result of test printing, by executing the test printing under an image forming condition that is set in accordance with one or more type candidates of the recording material, the one or more type candidates being extracted based on the recording material information detected by the first detector.

A belt device includes a first stretching member and a detector. The first stretching member stretches an endless belt capable of rotational movement. The detector detects a base of the belt and/or a density of a toner image on the belt. The first stretching member includes a first parallel area that is parallel to an axial direction, which is a direction of a rotation axis of the belt, and a first inclined area that is connected to an outer side of the first parallel area with respect to the axial direction and is inclined in a direction closer to the rotation axis. The detector detects a location corresponding to a first boundary between the first parallel area and the first inclined area or a location corresponding to a predetermined first adjacent area that is adjacent to and on an inner side of the first boundary.

An image forming apparatus is provided. The image forming apparatus includes an image forming part to form a pattern including at least one white dot line and at least one black dot line on an image forming medium using a photoconductive drum. A registration sensor is to sense an amount of light reflected from the image forming medium. A processor is to determine a state of the photoconductive drum based on the amount of sensed light in the pattern.

An image forming apparatus includes an image forming unit, an intermediate transfer member, a power source, and a control unit configured to perform a mode to output a test chart which is formed by transferring a plurality of test toner images from the intermediate transfer member to a plurality of sheets of the recording material. In a case where a jam occurred during execution of the mode, the control unit is configured to resume the mode after the jam has been recovered. In a case where the control unit resumes the mode after the jam has occurred during the execution of the mode, the control unit is configured to resume the mode from a first sheet of the plurality of sheets of the recording material regardless of a number of sheets of the recording material not discharged due to the jam.

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.

An image forming apparatus includes a detection unit that optically detects a density of a reference toner image for density measurement formed on an image carrier. Either a first detection method for detecting the density of the reference toner image by receiving specularly reflected light reflected by the image carrier and the reference toner image for density measurement formed on the image carrier or a second detection method for detecting the density of the reference toner image by receiving diffusely reflected light from the image carrier and the reference toner image, is selected in accordance with color information of a toner, the color information being stored beforehand in a storage unit, and the density of the reference toner image is optically detected.

An image forming apparatus, which is configured to execute calibration for controlling an image forming condition, includes a detection unit configured to detect an environmental state in which the image forming apparatus is installed; a prediction unit configured to predict, based on a plurality of detection results detected by the detection unit in a first period, a change in the environmental state in a second period after the first period; and a setting unit configured to set a timing of executing the calibration in the second period based on the change in the environmental state predicted by the prediction unit.

An image forming apparatus includes an image forming portion, a high-voltage generation circuit, a current detection portion and a control portion. The image forming portion includes an image carrying member, a charging device, an exposure device and a developing device which includes a developer carrying member for carrying a two-component developer. The control portion can perform a transfer memory prediction mode that includes a step of estimating, when a first reference image is formed, the level of occurrence of transfer memory based on the direct-current component of a development current flowing through the developer carrying member and a step of measuring, when the measured direct-current component of the development current is larger than a predetermined value, the amount of charge of the toner within the developing device and estimating the cause of occurrence of the transfer memory based on the measured amount of charge of the toner.