According to one embodiment, an image forming apparatus includes a plurality of process units, a transferring member, a sensor, and a processor. The plurality of process units include a photosensitive drum, an electric charger which charges the photosensitive drum, an exposing device which includes a plurality of light emitting element rows in a sub-scanning direction configured by the plurality of light emitting elements, and irradiates the photosensitive drum to form a latent image, and a developing device which attaches toner to the latent image to form a toner image. The transferring member receives the toner image from the photosensitive drum. The sensor detects the toner image transferred to the transferring member. The processor calculates a skew deviation amount based on the detection result of the sensor, and controls turning on and off the light emitting element based on a central tendency and the skew deviation amount.

An image forming device which forms an image for color correction in the margin of a continuous recording medium such as continuous paper as appropriate without causing erroneous detection by a mark sensor at a post-processing stage. In the image forming device, a printing data generator (control section) performs: acquiring a detection criterion to detect a post-processing image for use at the post-processing stage; creating a color correction image to be used for color correction of an original image according to the detection criterion; and arranging the color correction image as an outer area image in an area other than an original image formation area in printing data.

According to one embodiment, an image forming apparatus includes a plurality of process units, a transferring member, a sensor, and a processor. The plurality of process units include a photosensitive drum, an electric charger which charges the photosensitive drum, an exposing device which includes a plurality of light emitting element rows in a sub-scanning direction configured by the plurality of light emitting elements, and irradiates the photosensitive drum to form a latent image, and a developing device which attaches toner to the latent image to form a toner image. The transferring member receives the toner image from the photosensitive drum. The sensor detects the toner image transferred to the transferring member. The processor calculates a skew deviation amount based on the detection result of the sensor, and controls turning on and off the light emitting element based on a central tendency and the skew deviation amount.

An image forming apparatus as a first apparatus includes an image forming unit that forms an image onto a recording medium, a memory that stores first and second information, and a correcting unit that corrects an image formation position by the image forming unit in accordance with the first or second information. The first information is for correcting misregistration between a print position in the first apparatus and a print position in a second image forming apparatus as a second apparatus when an image is formed by the first apparatus and an image is subsequently formed by the second apparatus. The second information is for correcting misregistration between the print positions in the second and first apparatuses when an image is formed by the first apparatus, an image is subsequently formed by the second apparatus, and then an image is formed by the first apparatus.

An image forming apparatus of an embodiment comprises a printer unit to print a sheet with a plurality of single colors and generate a correction sheet including a plurality of single color regions at different positions between a first reference region and a second reference region. The first and second reference regions are a reference color. An image reading unit is configured to read the correction sheet. A processor is configured to calculate a shift amount in a main scanning direction of the printer unit for each single color region based on RGB luminance values obtained from the correction sheet by the image reading unit and to correct a printer scan position along the main scanning direction for each single color in the plurality of single colors corresponding to the single color regions using calculated shift amounts.

According to one embodiment, an image forming apparatus includes a plurality of process units, a transferring member, a sensor, and a processor. The plurality of process units include a photosensitive drum, an electric charger which charges the photosensitive drum, an exposing device which includes a plurality of light emitting element rows in a sub-scanning direction configured by the plurality of light emitting elements, and irradiates the photosensitive drum to form a latent image, and a developing device which attaches toner to the latent image to form a toner image. The transferring member receives the toner image from the photosensitive drum. The sensor detects the toner image transferred to the transferring member. The processor calculates a skew deviation amount based on the detection result of the sensor, and controls turning on and off the light emitting element based on a central tendency and the skew deviation amount.

An image forming apparatus is provided. The image forming apparatus includes a sensor to detect a toner concentration, and a processor to control a rendering of image-forming data to form an image on an image forming medium, according to a level of toner concentration saving that is adjusted based on the detected toner concentration.

An image forming apparatus is configured to calculate an estimated value of a color misregistration amount based on a first estimation expression when a temperature of an exposure device is under a temperature increasing state. The image forming apparatus is configured to calculate the estimated value of the color misregistration amount based on the first estimation expression when the temperature of the exposure device is under the temperature decreasing state and the exposure device is not in a thermally-deformed state. The image forming apparatus is configured to calculate the estimated value of the color misregistration amount based on a second estimation expression when the temperature of the exposure device is in the temperature decreasing state and the exposure device is in the thermally-deformed state. The image forming apparatus is configured to correct color misregistration based on the calculated estimated value.

An image forming apparatus includes a controller configured to execute: a task that measures a plurality of first color patterns; a task that, on the basis of a first output value corresponding to a measurement result of the first color patterns, determines a threshold value; a measurement task that measures a plurality of second color patterns; and a task that detects an amount of color misregistration on the basis of a result of a comparator comparing a second output value corresponding to a measurement result of the second color patterns with a threshold value corresponding to each of the second color patterns. In the measurement task, the controller controls whether or not to set the threshold value to the threshold value corresponding to each of the second color patterns on the basis of the first output value.

An image forming apparatus of an embodiment comprises a printer unit to print a sheet with a plurality of single colors and generate a correction sheet including a plurality of single color regions at different positions between a first reference region and a second reference region. The first and second reference regions are a reference color. An image reading unit is configured to read the correction sheet. A processor is configured to calculate a shift amount in a main scanning direction of the printer unit for each single color region based on RGB luminance values obtained from the correction sheet by the image reading unit and to correct a printer scan position along the main scanning direction for each single color in the plurality of single colors corresponding to the single color regions using calculated shift amounts.