In an image forming apparatus, when images are formed on a plurality of sheets, a controller controls an image forming unit to form a measurement image between an image which is to be transferred to a first sheet of the plurality of sheets and an image which is to be transferred to a second sheet of the plurality of sheets, controls a sensor to measure the measurement image, determines a feedback condition based on a length of each of the plurality of sheets in a conveyance direction, and controls an image forming condition based on a result of measurement performed by the sensor and the determined feedback condition, wherein the image which is to be transferred to the second sheet of the plurality of sheets is adjacent to the image which is to be transferred to the first sheet of the plurality of sheets on an image bearing member.

An image forming device is provided. The image forming device may include a transfer belt to move in a preset direction, a plurality of image generators to respectively generate a toner image on the transfer belt, and a controller to output an image generation signal to each of the plurality of image generators such that the plurality of image generators respectively generate a toner image. A plurality of toner images generated using the plurality of image generators are arranged on the transfer belt in parallel to each other, and an arrangement order of the plurality of toner images is identical to an arrangement order of the plurality of image generators.

An image forming apparatus includes a plurality of image forming units configured to form images, an image bearing member, a detection unit configured to detect a pattern image formed on the image bearing member, the pattern image being used for detecting a color misregistration, a controller configured to control the plurality of image forming units to form a plurality of first pattern images, each having a different color, and control the detection unit to detect the color misregistration, and a storage unit configured to store data on the color misregistration, wherein the controller corrects an image forming position based on the stored data, and wherein in a case where an error is detected in the data, the controller controls the plurality of image forming units to form a plurality of second pattern images, different form the plurality of first pattern images, before the plurality of first pattern images is formed.

In an optical scanning device, light emitting start timings of light emitting parts with respect to a reference light emitting part are stored in a storage part. In a correction mode, a light emitting timing correction control part performs first control for allowing positions of beam spots of the light beams emitted from the light emitting parts to be equal to each other, second control for allowing a light emitting part LD4 to emit a light beam at a plurality of different start timings and patch images to be formed on a intermediate transfer belt 281, and third control for correcting light emitting start timings of light emitting parts LD2 to LD4 on the basis of the start timing of the light emitting part LD4 at which the patch images has the highest concentration.

Provided is an image formation device including a photoreceptor configured to carry a toner image and a developer configured to form the toner image on a surface of the photoreceptor and configured such that the developer is a replaceable development unit, the image formation device including: a development bias application section configured to apply a development bias to between the photoreceptor and the developer; a stabilization control section configured to perform image stabilization control of determining a development bias value to be used in future by changing the development bias while measuring a density of the toner image formed by the developer, thereby obtaining the toner image with a target density; and a life determination section configured to determine expiration of use of the development unit when the development bias value determined by the stabilization control falls outside a preset acceptable range.

An image forming apparatus includes: a controller configured to: control first and second image forming units to form a plurality of groups of detection images, the plurality of groups of detection images being scaled based on a scaling factor, determine a plurality of detection start timings that respectively correspond to the plurality of groups based on the scaling factor, control a detection unit to detect the plurality of groups based on the determined detection start timings, and control the detected misregistration of a first image to be formed by the first image forming unit and a second image to be formed by the second image forming unit.

An image forming apparatus forms test patches, and detects the adhesion amounts of toner in the test patches. The image forming apparatus calculates an approximate equation approximates the relationship between a developing bias and an adhesion amount of toner, based on the developing biases when the test patches were formed and the adhesion amounts of toner of the test patches. Distance between test patches is {(2n1)/2} times of value L, where n is a natural number and L is a length of the photo conductor drum in a circumferential direction. The accuracy of toner adhesion amount control can be improved, and image density can be stabilized.

An image forming apparatus includes a first toner image forming unit for forming first toner image on a transfer belt with a first toner and a second toner image forming unit for forming a second toner image on the transfer belt with a second toner. A secondary transfer unit transfers the first and second toner images from the transfer belt to a sheet traveling in a sheet transport direction. A fixing unit fixes the first and second toner images to the sheet. A control unit controls the first toner image forming unit to form a first pattern, the second toner image forming unit to form a second pattern, and to leaving a margin on a downstream side of the sheet in the sheet transport direction that is greater than or equal to a circumferential distance of a fixing element in the fixing unit.

Prediction accuracy of a color misregistration amount in an image formation executed in an image forming apparatus is improved. The image forming apparatus comprises an optical box storing an optical system for irradiating a laser beam from a laser source to a photosensitive drum, a scanner temperature sensor provided near the optical box, and an environmental temperature sensor for detecting a surrounding temperature of the image forming apparatus, and a control section. When image formation is executed, the control section obtains a temperature Tscn detected by the scanner temperature sensor and a temperature Tenv detected by the environmental temperature sensor and calculates a prediction value of a position misregistration amount to the photoreceptor of the laser beam using the difference between Tscn and Tenv.

A image forming system of the present inventation includes a control section that causes a pattern image for image density control to be formed on an image carrier, and performs density correction control for correcting a density of a formed image on the basis of density information on the formed pattern image for image density control, wherein the control section determines a timing for performing the density correction control, on the basis of information corresponding to a density difference generated between images formed by the plurality of image forming apparatuses.