An image forming unit forms test images of a color of the same type as a first color using toner of a second color and toner of a third color, transfers a first and second test images, fixes the test images on a sheet, controls a sensor to read test images, determines sampling timings for the test images based on an output signal related to the first test image outputted from the sensor using a color filter of a fourth color, acquires a result of reading the test images based on a reading result of the test images on the sheet by the color sensor using a color filter of the first color, and the sampling timing, and determines a transfer voltage based on the result of reading the test images.

Disclosed is an image forming apparatus including: a fixation unit configured to heat a toner image formed corresponding to image data and fix the heated toner image onto a recording material; and a control unit configured to determine a fixation target temperature used by the fixation unit to heat the toner image on the basis of the image data, wherein the control unit performs a first determination to calculate a first target temperature on the basis of image density information in each of a plurality of regions in which the image data is divided in a main-scanning direction and a sub-scanning direction and a second determination to determine whether the image data is a text image, and determines the fixation target temperature on the basis of results of the first determination and the second determination.

An inspection device includes a processor configured to use, as correct image data, read image data obtained by reading an image-formed matter obtained by forming original image data on a recording medium, and, in a case where a first inspection of determining quality of read image data as an inspection target is performed using the correct image data, the read image data being obtained by reading a new image-formed matter, perform a second inspection on a blank portion or a solid portion included in the read image data as the inspection target, the second inspection using the original image data as the correct image data.

An image forming apparatus includes: an image forming unit configured to form an image on a sheet; a line sensor configured to read a sheet having test images formed thereon while the sheet having the test images formed thereon is conveyed; and a controller configured to: control the image forming unit to form the test images on the sheet; control the line sensor to read the sheet having the test images formed thereon; obtain read data related to the test images, the read data being output by the line sensor; and control, based on the read data, a geometric characteristic of an image to be formed on a sheet by the image forming unit, wherein the controller is configured to determine, in a reading area of the line sensor, whether dust is detected in a first area.

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.

A first test image has one line segment of a first color and another line segment of the first color. The second test image has one line segment of the first color and another line segment of a second color or has one segment of the second color or another segment of the first color. The third test image has one line segment of the second color and another line segment of the second color. The fourth test image has one line segment of the second color and another line segment of a third color or has one segment of the third color or another segment of the second color. The fifth test image has one line segment of the third color and another line segment of the third color. An apparatus obtains an amount of color misregistration based on the test images.

An image forming apparatus includes an image forming portion, an image bearing member, a transfer member, a voltage source, a density detecting portion, a display portion, a controller, and an operating portion. The controller is capable of executing an operation in a mode in which a test chart for adjusting a transfer voltage is outputted, and setting information on the transfer voltage set for during transfer on the basis of a detection result when the test chart is detected by the detecting portion is displayed at the display portion and is checked by user. The controller causes the display portion to display setting information on the basis of a correcting value and causes the user to check the setting information in the operation in the mode executed after the correcting value is inputted from the operating portion.

An image reading device includes an image reader and circuitry. The image reader is configured to read an image on a recording medium. The circuitry is configured to obtain defective image information and defect type information based on the image on the recording medium read by the image reader, and determine an abnormality of the image on the recording medium based on the defective image information and the defect type information.

An image forming apparatus includes an image carrier, an image forming unit, a transfer unit, a detector, a controller, an edge detector, and an abnormality detector. The detector detects developer attached to an image carrying surface at a position between a position where an image is formed and a position where the image is transferred. The controller controls the image forming unit such that a check image including an edge that extends in a direction intersecting the moving direction of the image carrying surface is formed in a region of the image carrying surface that passes through the detection position. The edge detector determines a position of the edge based on a detection status of the developer. The abnormality detector determines whether or not the image former is abnormal based on the position of the edge.

An image forming apparatus includes an image bearing member, an image forming portion, a transfer member, a power source, an acquiring portion, and a controller capable of executing an operation in an adjustment mode. A plurality of test toner images transferred onto a recording material in the occurrence in the adjusting mode include a first test toner image transferred under application of a first test voltage and a second test toner image transferred under application of a second test voltage different from the first test voltage. In the operation in the adjustment mode, the controller adjusts the transfer voltage set for transfer on the basis of first information on variation in image density acquired in different regions of the first test toner image and second information on variation in image density acquired in different regions of the second test toner image.