An image forming apparatus includes an image forming device, an image density detector, and an output change device configured to cause the image forming device to form a test toner image while cyclically changing a charging power based on a charging change pattern and a developing bias based on a developing change pattern, generate an image density fluctuation pattern of the test toner image in a rotation direction of a latent image bearer, generate a writing change pattern to cyclically change a power of latent image writing based on the image density fluctuation pattern of the test toner image and one of the charging change pattern and a correlative pattern correlated with the charging change pattern. The output change device is configured to cyclically change the power of latent image writing based on the writing change pattern during image formation according to a user command.

An image forming apparatus includes a controller configured to compare a threshold value and an output value corresponding to an intensity of light reflected from a detection image, and to detect a color misregistration amount based on a comparison result; an update unit configured to update the threshold value based on a previous output value corresponding to the intensity of the light reflected from the detection image; and an adjustment unit configured to adjust an emission intensity of the light emitting element. The update unit updates, in a case when the emission intensity is adjusted, the threshold value based on the previous output value, a previous emission intensity, and the emission intensity adjusted by the adjustment unit.

An image forming apparatus includes an image forming unit, an acquisition unit, a fixing unit including a heating member and a pressure member forming a nip, a temperature detecting unit, and a control unit. In a case where a toner density of a toner image on a k-th recording material of a plurality of recording materials is less than the toner density of the toner image on a (k-1)-th recording material of the plurality of recording materials, k being an integer greater than or equal to two, the control unit sets a fixing temperature of the k-th recording material to a temperature which is greater than a predetermined temperature predetermined based on image information of the toner image to be formed on the k-th recording material.

An image forming apparatus includes a toner pattern bearer to bear a first toner pattern having a first image area and a second toner pattern having a second image area different from the first image area. A toner adhesion amount detector detects a toner adhesion amount of toner of each of the first toner pattern and the second toner pattern. A toner degradation rate calculator calculates a first deviation in the toner adhesion amount of the first toner pattern and a second deviation in the toner adhesion amount of the second toner pattern based on the toner adhesion amount detected by the toner adhesion amount detector. The toner degradation rate calculator compares the first deviation with the second deviation and calculates a toner degradation rate based on a comparison result.

An image forming apparatus includes an image forming device, an image density detector, and a processor. The processor controls the image forming device to form a first test toner image, and controls the image density detector to detect an image density at the plurality of positions of the first test toner image. The processor adjusts an image forming condition so that the image density detected at each of the plurality of positions becomes a target image density, controls the image forming device to form a second test toner image based on the adjusted image forming condition, controls the image density detector to detect an image density at the plurality of positions of the second test toner image, determines whether a streak exists in the second test toner image based on the detected image densities, and executes a countermeasure to prevent an occurrence of the streak.

Provided is an image forming apparatus having high usability and securing both image quality and productivity. The image forming apparatus changes a rotational speed of a secondary transfer member depending on a basis weight of a sheet. The image forming apparatus performs digital sub-scanning scaling of correcting image data and polygon sub-scanning scaling of controlling a scanning speed during image formation so as to cancel out image deformation caused by change in rotational speed of the secondary transfer member. When giving priority to image quality, the image forming apparatus performs processing of the digital sub-scanning scaling and the polygon sub-scanning scaling, and when giving priority to productivity, the image forming apparatus performs only processing of digital sub-scanning scaling.

An image forming apparatus includes: a roller arranged in a position between a drive roller and an idle roller and downstream from the drive roller in a rotation direction of an intermediate transfer belt while pressing an outer surface of the belt; and a density measuring portion arranged between the drive roller and the roller applying pressure. The density measuring portion optically detects the density of a test patch formed on the outer surface and in a given position of a width direction of the belt. The density measuring portion includes: an optical sensor provided above the outer surface of the belt; and a support member abutting on an inner surface of the belt in a position in which the support member faces the optical sensor across the belt in the rotation direction.

An image forming apparatus including a controller, which starts rotation of a rotary polygon mirror when a predetermined condition is satisfied, rotates the rotary polygon mirror at a predetermined rotation speed based on a first pulse in a first state in which light beams are not emitted from a light source, thereafter starts emission of the light beams, switches a rotation control based on the first pulse to a rotation control based on the second pulse, and rotates the rotary polygon mirror at the predetermined rotation speed based on the second pulse in a second state in which the light beams are emitted from the light source, and thereafter detects a temperature of a drive circuit board by a temperature detector, and corrects color misregistration using a detected temperature of the temperature detector and the detection result of a pattern detector.

An optical detecting apparatus includes a substrate having a surface, on which a light emitter and a first light receiver are arranged, and a housing. The housing has a fixture surface, onto which the surface of the substrate is fixed, and an attachable surface on a side opposite to the fixture surface. The housing includes an emitted-light guiding path formed through the housing between the fixture surface and the attachable surface for light emitted from the light emitter to pass there-through and a first receiving-light guiding path formed through the housing between the fixture surface and the attachable surface for light to be received by the first light receiver to pass there-through. The housing includes an attachable portion formed on the attachable surface. The attachable portion protrudes in a direction to extend away from the substrate.

An image forming apparatus includes an image bearer, a charging, a charge power supply to supply a charging bias to the charging device, a developing device, a toner adhesion amount detector, an environment detector, and a controller to determine whether to execute a charging bias adjustment process in which the charging device charges the image bearer to have different potentials, the developing device supplies the toner to the image bearer according to the different potentials, the toner adhesion amount detector detects the amount of toner adhering to the image bearer, and the controller adjusts the charging. The controller includes a memory device to store the environment data, and is configured to compare the environment data with previous environment data stored in the memory device, and determine not to execute the charging bias adjustment process when an environment change amount is not greater than a threshold.