An optical scanning apparatus includes a light source, an optical deflector having a rotary polygon mirror to deflect a light beam from the light source, a scanning optical system configured to focus the light beam deflected by the optical deflector on a target surface, a sync detecting sensor configured to determine a write start timing on the target surface, and a processing unit configured to correct detection data of the sync detecting sensor based on a measured value of a time needed for one revolution of the rotary polygon mirror.

An image forming apparatus includes an image forming section, a transferring member, and a controller. The image forming section includes an image supporting member and a developer supporting member. The image supporting member supports a latent image on a surface of the image supporting member. The developer supporting member supports, on a surface of developer supporting member, a developer that develops the latent image. The transferring member transfers, onto a transferred medium as a medium on which a transfer is to be performed, an image formed by the image forming section. The controller controls, as an amount of the developer, a developer amount to be fed to the latent image supported on the surface of the image supporting member, on the basis of a traveling velocity of the transferred medium.

An image forming apparatus includes an image carrier, an image carrier driver which rotates the image carrier, a rotation detector which detects rotation of the image carrier, a rotary member in contact with the image carrier, a rotary member driver which rotates the rotary member, a first controller which controls the rotary member driver, and a second controller. The second controller controls the image carrier driver based on an output of the rotation detector and also controls the image carrier driver in a manner which attenuates a fluctuation component at a specific frequency. When the first controller changes a surface velocity of the rotary member, the second controller controls the image carrier driver in a manner that attenuates a fluctuation component at a specific frequency related to the changed surface velocity of the rotary member.

An image forming apparatus includes a plurality of developing member to form toner images, respectively, a transfer member to sequentially transfer the toner images onto a recording material and to overlappingly form toner on the recording material. A fixing member presses and heats the recording material on which the toner images are transferred and fixes the toner images on the recording material. A storage medium stores a usage history of the developing member. A controller controls a fixing temperature of the fixing member. The controller determines the fixing temperature based on a difference between the usage history of one of the developing member stored in the storage medium and the usage history of another of the developing member.

An image forming apparatus includes: a formation body on which a latent image is developed so that an image is formed; a transfer belt with an outer peripheral surface onto which the image formed on the formation body is transferred, the transfer belt having an annular shape; a driving roll around which the transfer belt is wound and that causes the transfer belt to revolve; a transfer body that transfers, at a transfer region between the transfer body and the transfer belt, the image from the transfer belt to a recording medium while transporting the recording medium; a drive mechanism that rotationally drives the transfer body; a detection unit that detects a predetermined rotation position of the transfer body; a writing unit that writes the latent image on the formation body based on a detection timing at which the detection unit detects the rotation position; and a speed adjustment mechanism that adjusts a rotation speed of the transfer body rotated by the drive mechanism each time the transfer body makes one rotation, that switches between a first adjustment pattern and a second adjustment pattern in which a speed profile is different from the first adjustment pattern each time the transfer body makes one rotation, and that synchronizes a switching timing, at which switching between the adjustment patterns is performed, with the detection timing.

An image forming apparatus includes a transfer roller, a fuser, a chute, a drive source, a reciprocating mechanism, and a controller. The transfer roller transfers toner to a sheet. The fuser fixes toner on the sheet. The chute is located upstream from the fuser in a sheet conveying direction. The chute is configured to convey the sheet toward the fuser. The chute is movable between a first position and a second position. The reciprocating mechanism reciprocates by drive force from the drive source and moves the chute between the first position and the second position. The controller executes: a first mode of actuating the drive source when conveying one sheet; and a second mode of not actuating the drive source when conveying one sheet. The controller switches between the first mode and the second mode in a middle of a print job.

A test image is formed by an image forming unit. A sensor receives light reflected from a test image on an intermediate transfer member passing through a detection position and outputs an output signal based on a reception result of the reflected light. A controller reduces density unevenness of images to be formed in a rotation direction of a photosensitive member based on a correction data, determines a reference output signal used to generate the correction data among output signals output from the sensor in time series based on a timing at which the test image reaches the detection position.

When an outer diameter of a charging member is defined as Hc, a ratio of the circumferential velocity of the charging member to the circumferential velocity of an image bearing member is defined as Rc, an outer diameter of a developer bearing member is defined as Hd, and a ratio of the circumferential velocity of the developer bearing member to the circumferential velocity of the image bearing member is defined as Rd, the relationship Hc/RcHd/Rd is satisfied.

An image forming apparatus includes: a plurality of photoreceptors; a plurality of exposure heads provided so as to correspond to the plurality of photoreceptors, respectively, each of the plurality of exposure heads including a plurality of light emitting units configured to emit light for exposing the corresponding photoreceptor, the plurality of light emitting units being arranged along a rotation axis line of the corresponding photoreceptor; and a generation unit configured to generate a line synchronization signal for each of the plurality of exposure heads to control a light emission timing in a rotating direction of the corresponding photoreceptor, the generation unit being configured to adjust a cycle of the line synchronization signal in accordance with each of the plurality of exposure heads.

An image forming apparatus includes a photoreceptor that holds a toner image to be transferred to a paper sheet, a charger that charges a surface of the photoreceptor, a developer that supplies toner to the surface of the photoreceptor, a cleaning unit that collects toner stuck to the photoreceptor, and a unit that changes a positional relationship between the photoreceptor and the charger and/or a positional relationship between the photoreceptor and the cleaning unit under a predetermined condition after the photoreceptor stops.