Abstract: A color image forming apparatus which is capable of performing color misregistration correction, and registration of images and a recording sheet while reducing the toner consumption amount. An image forming section is caused to form a first reference image having a first density for adjusting a density of an adjusting image, and a second reference image having a second density different from the first density. A sensor detects the first reference image and the second reference image. The first density is determined as a density of the adjusting image, if an output signal level of the sensor at a time of detection of the first reference image is not lower than a predetermined value, and the output signal level of the sensor at a time of detection of the second reference image is lower than the predetermined value.

Abstract: An image forming apparatus capable of ensuring a sufficient difference between amounts of light reflected from a base such as a transfer material and from a toner pattern in the detection of the toner pattern for registration correction control by a reflective optical sensor. The image forming apparatus includes a pattern generator for generating a toner pattern, a pattern detection sensor for detecting the toner pattern formed on the intermediate transfer belt, a pattern density decider for determining the density of the toner pattern that makes the amount of light received by the sensor in detection of the toner pattern equal to or less than a predetermined value.

Abstract: An image forming apparatus includes a pattern forming unit which forms a light amount adjustment pattern on an image carrier belt, a light amount control unit which controls the amount of light irradiating the image carrier belt and pattern, a detection sensor which detects reflected light amounts from the image carrier belt and pattern with respect to the irradiating light amount and stores the detection results in a storage unit, a calculation unit which calculates the correspondence between the irradiating light amount and the reflected light amounts from the image carrier belt and pattern on the basis of the detection results and stores the calculation results in the storage unit, and a light amount decision unit which decides, on the basis of the calculation results, a light amount at which the difference between the reflected light amounts from the image carrier belt and pattern exhibits a value set in advance.

Abstract: A switch unit applies a voltage to each of a plurality of unit electrodes arranged in a matrix in a base material of a high resistance of an electrode array. A control unit controls the switch unit, changes a pattern of the voltage to be applied to the plurality of unit electrodes arranged in the matrix, and thereby generates an electrostatic force in a sheet conveying direction and a direction orthogonal to the sheet conveying direction, between a sheet and the electrode array.