An example shutter unit includes a motor including a driving shaft to rotate in a first rotation direction and to rotate in a second rotation direction opposed to the first rotation direction, a first shutter part to selectively expose a light window by receiving a driving force transferred from the driving shaft when the driving shaft rotates in the first rotation direction or the second rotation direction, and a second shutter part to selectively expose a sensor by receiving the driving force transferred from the driving shaft when the driving shaft rotates in the second rotation direction.

An image forming apparatus includes a transfer belt, a plurality of endless rotational bodies, an image forming device, a pattern sensor, and processing circuitry. The image forming device forms correction patterns including a first pattern as a straight line pattern orthogonal to a conveyance direction of the correction patterns and a second pattern as one of a straight line pattern orthogonal to and an oblique line pattern inclined with respect to the conveyance direction. The processing circuitry causes the image forming device to form the correction patterns using a correction value such that the second pattern included in one correction pattern on the transfer belt is same in color and shape as the second pattern included in at least one correction pattern of a preceding correction pattern and a following correction pattern in the conveyance direction with respect to the one correction pattern.

An image forming device that forms a toner image on a surface of a photoreceptor, transfers the toner image to a recording material and outputs a printed recording material, includes: an intermediate transfer body that primarily transfers the toner image on the photoreceptor and secondarily transfers the toner image to the recording material; a cleaner that removes a toner left on the surface of the photoreceptor; a patch forming unit that forms a toner patch between two adjacent toner images when multiple toner images are continuously formed on the surface of the photoreceptor; a concentration detector that detects concentration of the toner patch primarily transferred to the intermediate transfer body from the photoreceptor; and a patch adjuster that adjusts toner amount used for forming the toner patch based on a result detected by the concentration detector.

An image forming apparatus includes a storage unit and a charging amount acquisition unit. The charging amount acquisition unit performs a charging amount acquisition operation for forming a measurement toner image on the image carrier while changing the frequency of the alternating current voltage of the development bias with a potential difference in a direct current voltage between the developing roller and the image carrier being kept constant, acquiring a tilt of a measurement straight line representing a relationship between the change amount of the frequency and a density change amount of the measurement toner image, and acquiring the charging amount of the toner based on the acquired tilt of the measurement straight line and the reference information in the storage unit.

An image forming apparatus includes a storage unit and a charging amount acquisition unit. The charging amount acquisition unit forms a measurement toner image on the image carrier while changing the frequency of the alternating current voltage of the development bias with the potential difference in the direct current voltage between the developing roller and the image carrier being kept constant, acquires a tilt of a measurement straight line representing a relationship between the change amount of the frequency and the density change amount of the measurement toner image, based on the change amount of the frequency and a result of detecting density of the measurement toner image in the density detecting unit, and acquires a charging amount of the toner included in the measurement toner image formed on the image carrier based on the acquired tilt of the measurement straight line and the reference information in the storage unit according to the toner density detected by the toner density detecting unit.

An image forming apparatus includes an image bearing member, a transfer member, a voltage source, a sensor configured to detect a current value or a voltage value, an image detecting portion, and a controller capable of executing an operation in a mode for setting a transfer voltage to be applied to the transfer member, on the basis of a result of detection of a test chart formed on a test recording material. The controller sets the transfer voltage on the basis of a first detection result acquired by the sensor under application of a voltage to the transfer member when the recording material is absent in the transfer portion and a second detection result acquired by the sensor under application of the test voltages to the transfer member when the test recording material is present in said transfer portion during the operation in the mode.

A first provider for providing a printer, a second provider for providing a print medium, a client which performs printing on the print medium using the printer, and a management section for processing and storing information are coupled to each other via a network. The first provider provides the second provider with a provider printer and a profile preparation tool. The second provider executes a process of preparing a profile corresponding to a combination of the provider printer and the print medium using the same, and transmitting printing setup information including the profile to the management section with respect to one or more print media. The client receives the printing setup information corresponding to the combination of the client printer used in printing and the print medium used in printing from the management section, performs setup based on the printing setup information on software for controlling the client printer and performs printing.

An image forming apparatus comprises a first temperature detector to detect a temperature of a first portion of an optical scanning device in a printer. The first portion is proximate to a heat generating element in the optical scanning device. A second temperature detector is provided to detect a temperature of a second portion of the optical scanning device, which is farther from the heat generating element than the first portion. A controller is configured to perform alignment control for correcting a color positional shift of the printer when either a detected temperature change of the first portion is greater than or equal to a first threshold value or a detected temperature change of the second portion is greater than or equal to a second threshold value.

There is provided a method for controlling an electrophotographic apparatus including forming a first measurement image by performing first halftone processing on image data, forming a second measurement image by performing second halftone processing different from the first halftone processing on the image data, measuring densities of the first measurement image and the second measurement image, calculating a density difference between each of densities of the measurement images, determining whether the density difference satisfies a predetermined reference value, and applying a surface treatment on an electrophotographic photosensitive member if the density difference does not satisfy the reference value, during a non-image formation period.

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.