An example operating method of an image forming apparatus includes detecting a position change of a beam with respect to a certain color in a main scanning direction, based on a change in a detection time at which the beam with respect to the certain color is detected by a beam detecting apparatus in the main scanning direction, detecting a position change of the beam with In respect to the certain color in a sub-scanning direction, based on a change in a detection time at which the beam with respect to the certain color is detected by the beam detecting apparatus in the sub-scanning direction, and correcting a value of at least one parameter used for alignment between an image of a reference color and an image of the certain color, based on the position changes of the beam in the main scanning direction and the sub-scanning direction.

A measuring device a measurement unit configured to measure an image on a sheet, the measurement unit including a light emitting portion configured to illuminate the sheet with light, and a detecting portion configured to detect light reflected by the sheet; a supporting unit supporting the measurement unit; and a driving unit configured to move the measurement unit supported by the supporting unit in a scanning direction. A size, in the scanning direction, of a detectable range of the detecting portion in which the detecting portion is capable of detecting the reflected light from the sheet is larger than a size, in a sub-scanning direction perpendicular to the scanning direction and a normal direction of a surface of the sheet, of the detectable range of the detecting portion.

An image forming apparatus includes an image forming device and circuitry. The image forming device forms an image with colorants of different colors. The circuitry determines whether there is a possibility that a shortage of a colorant adhesion amount occurs in primary-color image formation using a colorant of a primary color and cause the image forming device to perform two-color image formation in which only secondary-color image formation using a colorant of a secondary color different from the colorant of the primary color is added to the primary-color image formation using the colorant of the primary color to form an image to be formed with the colorant of the primary color, when the circuitry determines that there is a possibility that the shortage of the colorant adhesion amount occurs in the primary-color image formation using the colorant of the primary color.

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 plurality of light beams. The scanning portion scans the plurality of light beams to form a plurality of electrostatic latent images, respectively corresponding to a plurality of colors including at least one reference color and at least one non-reference color, in an image forming portion. The first correction portion applies an external mechanical force to an optical element located in a path of a reference beam, corresponding to the reference color, among the plurality of light beams to correct distortion of a scan line of the reference beam. The second correction portion controls the light source portion to correct distortion of a scan line of a non-reference beam, corresponding to the non-reference color, among the plurality of light beams.

A color accuracy verification device includes: a hardware processor that: acquires a colorimetric value for each color patch of color accuracy verification charts generated by a plurality of printers; stores the colorimetric value in time series; sets a target printer to carry out color accuracy verification; and verifies color accuracy based on: the colorimetric value of the target printer stored in the hardware processor; and a verification reference value set in advance; and a display that displays a verification result by the hardware processor for the target printer.

A measuring device a measurement unit configured to measure an image on a sheet, the measurement unit including a light emitting portion configured to illuminate the sheet with light, and a detecting portion configured to detect light reflected by the sheet; a supporting unit supporting the measurement unit; and a driving unit configured to move the measurement unit supported by the supporting unit in a scanning direction. A size, in the scanning direction, of a detectable range of the detecting portion in which the detecting portion is capable of detecting the reflected light from the sheet is larger than a size, in a sub-scanning direction perpendicular to the scanning direction and a normal direction of a surface of the sheet, of the detectable range of the detecting portion.

A measuring device a measurement unit configured to measure an image on a sheet, the measurement unit including a light emitting portion configured to illuminate the sheet with light, and a detecting portion configured to detect light reflected by the sheet; a supporting unit supporting the measurement unit; and a driving unit configured to move the measurement unit supported by the supporting unit in a scanning direction. A size, in the scanning direction, of a detectable range of the detecting portion in which the detecting portion is capable of detecting the reflected light from the sheet is larger than a size, in a sub-scanning direction perpendicular to the scanning direction and a normal direction of a surface of the sheet, of the detectable range of the detecting portion.

An image forming apparatus includes a first plurality of image forming sections that form a first toner image for adjustment and transfer the first toner image for adjustment to a medium; a second plurality of image forming sections that form a second toner image for adjustment and transfer the second toner image for adjustment to the medium; and a detection device configured to detect a misregistration between the first toner image for adjustment transferred to the medium and the second toner image for adjustment transferred to the medium.

A deviation detection device to detect a deviation of a rotator includes a contact member disposed in contact with the rotator and configured to move, following a deviation of the rotator in a width direction of the rotator. The deviation detection device further includes a deviation detector configured to detect a direction of the deviation and a deviation amount of the rotator based on a displacement of the contact member, and a wear detector configured to detect a state in which an amount of wear of the contact member has reached a threshold.

An apparatus and method for compensating for variation of the image placement for each color station in an intermediate transfer drum system. A sensor detects the image placed by the previous station and triggers the imaging on the drum such that it properly registered to the previous image. However, the variation of the drum's radius results in runout which creates an error in the image placement, since the surface drum travel will be larger or smaller than expected. The method to correct for a lead edge offset for radial runout involves dividing the drum into regions and calculating an offset center of each region. As the drum transitions from region to region the offset value is updated to determine when to start imaging for proper placement on the sheet. The offset can be derived from the image runout to find the distance traveled from the transfer point or can be measured directly from color-to-color registration variation.