According to an embodiment, an image forming apparatus executes, if an execution frequency setting of positional deviation correction in setting information is equal to or larger than a reference value, the positional deviation correction by using an image pattern for positional deviation measurement that is formed to be equal to or larger than one cycle of a transfer belt. Further, the image forming apparatus executes, if the execution frequency setting of the positional deviation correction in the setting information is less than the reference value, the positional deviation correction by using an image pattern for positional deviation measurement that is formed to be smaller than one cycle of the transfer belt.

When the dimension of a primary transfer roller in the width direction is represented by Wa, the dimension of a counter-sensor member in the width direction is represented by Wb, the dimension of an intermediate transfer belt in the width direction is represented by Wc, and the maximum dimension of a sheet in the width direction is represented by Wd, then the relationship WdWa<WbWc is fulfilled. The transfer position of a test pattern image is a position a predetermined distance away, inward in the width direction, from the edge of the intermediate transfer belt in the width direction. The predetermined distance is twice or more the distance in the width direction from the edge of the intermediate transfer belt in the width direction to the edge of the primary transfer roller in the width direction.

An image forming apparatus includes an image forming section, an intermediate transfer belt, and a stretching roller. The intermediate transfer belt has a pair of test regions on opposite sides of a printing region in the width direction, and the image forming section transfers a test pattern image to the test regions. The image forming apparatus further includes an image density sensor and a counter-sensor member having a counter portion facing the image density sensor across the intermediate transfer belt. The edge positions of the counter portion in the width direction are inward, in the width direction, of the edge positions of the stretching roller in the width direction.

A control unit of an image forming apparatus can perform a density correction mode to correct toner density, based on detection results of toner density of a plurality of reference images formed with density gradations changed sequentially in a plurality of steps, detects presence or absence of a change in the voltage in each density gradation, based on the toner density detection value detected in the density correction mode, and if the density gradation has a specific density gradation in which a change in the voltage is detected, it corrects the toner density of the specific density gradation, using the detection values of density gradations before and after the specific density gradation.

Provided is an image forming apparatus having a process cartridge which includes: an image bearing member; a developer bearing member which develops an electrostatic latent image with developer; a accommodating chamber which contains the developer; and a memory. The image forming apparatus includes: a detector for emitting light to a patch of a developer image, detecting reflected light; and a controller for performing image density control when controlling image density to form the developer image, based on a value of an image data and information on the reflected light. The memory stores information corresponding to a developer amount in the accommodating chamber, and the controller changes the patch pattern between a case where the information in the memory is information relating to a first amount and a second amount.

An image forming method performed in an image forming apparatus to form an image on a sheet includes receiving image data, and in a case where a first image is formed in a first area on a first surface of the sheet, a first test image for adjusting an image forming condition is formed in a second area on the first surface of the sheet and a second image is formed on a third area, corresponding to the second area, on a second surface opposite to the first surface of the sheet, deleting, in the image data, image data that corresponds to the third area of the second surface. In addition, an image is formed based on the image data in which the image data that corresponds to the third area was deleted.

An image-forming apparatus employing an electrophotographic method that scans a surface of an image carrier with multi-beams emitted from a plurality of light emitting elements based on image data includes a density smoothing processor that performs a density smoothing process to smooth a density level difference of an image subjected to electronic bow correction, a density correction processor that performs density correction on the image subjected to the bow correction by light amount correction of a surface-crossing exposure segment, and a light emitting element driver controller that controls light emission of a plurality of light emitting elements of a light beam emitter based on the image data subjected to the density smoothing process and a control signal subjected to the density correction.

An information processing system includes a processor configured to: when an image quality abnormality appears in a test chart generated under a normal image forming condition along a sheet feed direction at time of printing of the test chart, acquire the test chart generated under the normal image forming condition as a reference image; acquire, as a different image forming condition image, a test chart generated under an image forming condition which is different from the normal image forming condition and is for allowing a user to determine an image forming process causing the image quality abnormality; cut out, from the reference image, an image that includes at least a part of an appearance portion of the image quality abnormality and has a predetermined width in the sheet feed direction; cut out, from the different image forming condition image, an image having a predetermined width in the sheet feed direction; and cause the images cut out from the reference image and the different image forming condition image to be arranged and displayed on one screen with positions of the images in a direction orthogonal to the sheet feed direction being aligned.

A control device selects one of a plurality of chromatic colors as a target chromatic color according to a consumption status of developing agents of the plurality of chromatic colors. The control device causes an image forming portion to execute a process of forming, on a surface of a transfer medium, a plurality of chromatic color test images of the plurality of chromatic colors, and a superimposed test image in which a black test image is superimposed on a background image of the target chromatic color. The control device acquires a test detection signal of an amount of diffuse reflection light in each of areas of the plurality of chromatic color test images and the superimposed test image on the surface of the transfer medium. The control device adjusts timing of image formation of the plurality of colors by the image forming portion based on the test detection signal.

An image forming apparatus includes: a setting unit configured to set an exposure luminance; and a processing unit configured to generate first image data, which is a set of bit data for controlling emission or non-emission of light-emitting elements of a exposure head, and second image data, which is obtained by increasing/decreasing light-emitting elements that emit light in the first image data. The processing unit is configured to generate the second image data by increasing/decreasing, in a first region, which excludes an edge region inside a region in which pieces of bit data indicating emission are contiguous in the first image data, bit data indicating emission, according to a ratio of a setting value of the exposure luminance and a reference value of the exposure luminance.