A glossiness detector includes a glossiness sensor, a glossiness corrector, and a reference plate. The glossiness corrector corrects glossiness detected by the glossiness sensor. The reference plate is used for correction processing of the glossiness sensor. Then, the glossiness corrector acquires a glossy reflection profile of the reference plate that has been detected in advance. The glossiness corrector corrects the glossiness according to the reference plate on the basis of the glossy reflection profile and a gloss distribution of the reference plate that has been detected by the glossiness sensor.

An image forming apparatus to form a toner image on a recording material includes a photosensitive member and an optical scanning unit. The optical scanning unit includes an optical scanning unit, an optical box, a cover member, and a moving unit movable to an outside of the image forming apparatus. The optical scanning unit and the moving unit are arranged so that the moving unit and the optical scanning unit are opposed to each other when the moving unit is located in an inside of the image forming apparatus. The optical scanning unit is disposed so as to allow a user to touch the optical scanning unit through a space generated in the inside of the image forming apparatus when the moving unit is moved to the outside of the image forming apparatus. Between the optical box and the cover member, the cover member is opposed to the moving unit.

An image forming apparatus includes a photoconductor, an exposure device, and a shutter assembly. The exposure device includes a light source configured to expose the photoconductor. The light source is repositionable between a proximity position at a first distance from the photoconductor and a separation position at a second distance from the photoconductor. The first distance is less than the second distance. The shutter assembly is configured to move away from the light source in response to the light source moving toward the proximity position. The shutter assembly is configured to move to cover the optical path of the light source in response to the light source moving toward the separation position.

A control circuit executes voltage adjustment processing of adjusting a voltage output from a transfer power source so that a current detected by a detection circuit becomes a predetermined current value. The voltage adjustment processing is executed before a toner image is transferred from at least one of a first image bearing member and a second image bearing member to an intermediate transfer belt. A processor determines whether the second transfer member is in a state of contact or is in a state of separation on the basis of behavior of the current detected by the detection circuit in a period in which the control circuit is executing the voltage adjustment processing.

An image forming apparatus includes an image processor configured to convert image data based on a first conversion condition; an image forming unit configured to form an image on a sheet based on the image data converted by the image processor, the image forming unit having an image bearing member on which the image is to be formed, a transfer unit configured to transfer the image from the image bearing member onto the sheet, and a fixing unit configured to fix the image to the sheet; a conveyance roller configured to convey the sheet having the image fixed thereto; a reading unit configured to read a pattern image on the sheet conveyed by the conveyance roller; and a detector configured to detect a pattern image on the image bearing member.

An image forming apparatus includes a formation target that is wound around rotating bodies including a driving roller and transported by the rotating bodies including the driving roller while forming a shape having linear portions each of which forms a different angle, which is an acute angle or an angle of zero degrees, with a horizontal direction when viewed in an axial direction of the driving roller, first image forming bodies that are arranged along one of the linear portions in such a manner as to be spaced apart from each other by a first distance and that form images onto the formation target, and second image forming bodies that are arranged along another one of the linear portions, the other linear portion forming the angle larger than the angle formed by the one linear portion, in such a manner as to be spaced apart from each other by a second distance shorter than the first distance and that form images onto the formation target.

An image forming apparatus is capable of being attached with a toner supply container. The toner supply container stores a toner that is to be supplied to a developing portion. An attachment location of the toner supply container is below a light scanning portion in a vertical direction.

An image forming apparatus includes: an annular endless belt; a drive roller, around which the endless belt is wound and which moves the endless belt; a first tension roller, around which the endless belt moved by the drive roller is wound; a biasing mechanism connected to the first tension roller and including an elastic member that applies a tension to the endless belt via the first tension roller; a second tension roller, around which the endless belt moved by the drive roller is wound at a different position from the first tension roller; and a moving mechanism connected to the second tension roller to move the second tension roller in directions closer to and away from the endless belt. A range of adjustment of a circumferential length of the endless belt by the moving mechanism is larger than a range of adjustment of the circumferential length of the endless belt by the biasing mechanism.

An image forming apparatus includes a printhead configured to add energy to an image material; and a control unit configured to output, based on image data, a signal pattern for controlling energy to be added by the printhead to the image material including a plurality of color development layers that have different color development characteristic and develop colors in accordance with the added energy. When causing at least two of the plurality of color development layers to develop colors, the control unit generates, based on at least two signal patterns generated to cause the at least two color development layers to develop colors, a signal pattern of an OR of the at least two signal patterns and outputs the signal pattern.

In an image forming apparatus, upon receipt of a printing instruction, a controller starts rotation of a heating member, starts rotation of a photoconductor drum when a standby time has elapsed from a time of the start of the rotation of the heating member, starts conveyance of a sheet after the start of the rotation of the photoconductor drum, and forms a toner image on the sheet after the start of the conveyance of the sheet. The controller is configured to be operated in one of selectable modes including a multicolor mode in which a toner image is formed using both of toner of a first color and a second color and a monochrome mode in which a toner image is formed using toner of the second color only. The standby time adopted in the monochrome mode is longer than the standby time adopted in the multicolor mode.