An image forming apparatus, to which an external measurement device is connectable, including an image processor, a printer, a sensor arranged on a conveyance path, a controller that performs first processing for generating color processing condition based on a measurement result of measurement images of the sensor, the measurement images including a first measurement image and a second measurement image, wherein a length of the second measurement image in a conveyance direction is longer than a length of the first measurement image in the conveyance direction, and performs second processing for generating conversion condition, based on a measurement result of predetermined measurement images by the sensor and measurement data output from an external measurement device, wherein a length of a predetermined measurement image included in the predetermined measurement images in the conveyance direction is longer than the length of the first measurement image in the conveyance direction.

A system and method for determining print cartridge authenticity in a printer includes an electrostatic process unit with a photoconductive drum configured to selectively generate a toner pattern from an associated toner cartridge based at least in part on electronic data associated with the toner cartridge. A transfer belt receives the toner pattern from the photoconductive drum and a sensor sensing the toner pattern on the transfer belt. A processor compares the toner pattern with a sensed toner pattern and generates an error condition when the toner pattern does not substantially match the sensed toner pattern. The toner includes an infrared reflective additive or an ultraviolet fluorescing additive and the sensor is configured to sense in the infrared or ultraviolet frequencies. The processor is configured to generate an error condition when the additive is not sensed by the sensor.

An image forming apparatus includes an image bearing member, a developing device, a toner content detecting portion, a toner supplying device, an image ratio calculating portion, a toner image density detecting portion, an adjusting portion, and a controller. The controller is configured to control an execution frequency of the adjusting portion so that execution by the adjusting portion is carried out after a number of times of image formation after occurrence of a change rate of the image ratio that is greater than a predetermined change rate reaches a first value, and execution by the adjusting portion is carried out after the number of times of image formation after occurrence of a change rate of the image ratio that is less than the predetermined change rate reaches a second value greater than the first value.

A developing device includes a hardware processor that performs control not to cause an image to be formed on an image bearing member by a first developer bearing member and to cause a first image to be formed on the image beating member by a second developer bearing member, in which the hardware processor corrects developing conditions of the plural developer bearing members based on a developability detection result of the first image formed by the second developer bearing member.

An image-forming apparatus includes: a charge device that comes into contact with a photoreceptor and charges the photoreceptor; a separation mechanism that holds the photoreceptor and the charge device in a separate state that is removable; an exposure device; a developing device that forms a toner image; a toner adhesion amount sensor that detects a toner image; an image quality adjuster that controls a voltage applied to the charge device, a voltage applied to the developing device, an amount of light during exposure, and detection of the toner image and a density of the toner image; and a separation removal confirmer that, with the toner adhesion amount sensor, detects whether a toner image is formed in spite of unexposure during an initialization operation of a image forming process to perform separation removal confirmation as to whether the separate state by the separation mechanism has been removed.

An image inspection device includes: an illumination part extending in a width direction of a medium, which intersects a medium transport direction, so as to face a medium transport path, and configured to radiate light on an image formed on a surface of the medium; a reading part configured to read reflected light from the image as image inspection information; and a cooling part configured to cool an entire area of the illumination part in the width direction of the medium. The cooling part includes one blowing part provided on one side in the width direction of the medium and configured to suck and blow outside air, a first guide extending in the width direction of the medium and configured to guide the air blown from the blowing part to a flow path extending in the width direction of the medium, and a second guide configured to guide the air, guided by the first guide, in the medium transport direction to a space where the illumination part is disposed, and distribute the air such that an air volume is uniform over the entire area of the illumination part in the width direction of the medium.

An image forming apparatus includes a conveyor that conveys continuous paper, a speed detector that contacts the continuous paper conveyed by the conveyor to detect a conveyance speed of the continuous paper, and a hardware processor that controls the conveyor based on a detection result detected by the speed detector so that the conveyance speed of the continuous paper reaches a target value, wherein the hardware processor adjusts the target value based on at least one of information about the continuous paper and information about a job.

An image forming apparatus includes: multiple image carriers holding developers; multiple potential detectors that are mounted in a first scanning direction on each of the image carriers and detect surface potentials of the image carriers; an intermediate transfer body to which the developers held by the image carriers are transferred; and multiple density detectors that are mounted in the first scanning direction of the intermediate transfer body and detect densities of the developers transferred to the intermediate transfer body. A subset of the potential detectors is mounted at a location corresponding to a location where the density detectors are mounted and a subset of the potential detectors is mounted at a location that is common to the image carriers.

An image forming apparatus includes an image forming unit to form an image based on an image forming condition; a sensor to measure a measurement image formed by the image forming unit; and a controller to obtain information correlated with a change in density of an image to be formed by the image forming unit, control the sensor to measure the measurement image, determine first data related to density of the image to be formed by the image forming unit, determine, based on a result of measuring the measurement image, second data related to density of the image to be formed by the image forming unit, and generate the image forming condition based on a weighted average of the first data and the second data.

An image forming apparatus includes a controller configured to control a first image forming unit such that while a plurality of images are being sequentially formed, a first pattern image is formed in a first sheet-to-sheet area between a first black image and a second black image among the plurality of images on a first photosensitive body, and control the second image forming unit such that while the plurality of images is being sequentially formed, a second pattern image are formed in a second sheet-to-sheet area between a first color image and a second color image among the plurality of images on a second photosensitive body. The first sheet-to-sheet area in a case where the first pattern image is formed without the second pattern image being formed is narrower than the first sheet-to-sheet area in a case where the first pattern image and the second pattern image are formed.