An image forming apparatus includes a photoconductor to form an electrostatic latent image, an optical writing device, a first light emitter, a second light emitter, a reflector, a synchronization detector, and circuitry. The optical writing device includes a first light emitter to irradiate a first light and a second light emitter to irradiate a second light. The reflector deflects the first light and the second light. The synchronization detector detects the first light and the second light to detect a writing start timing of the electrostatic latent image. The circuitry outputs a light-emission control signal to control light emission state, outputs multiple gain signals corresponding to the first light emitter and the second light emitter, selects one gain signal from the multiple gain signals as a gain selection signal, and switches a gain of the synchronization detector based on the one gain signal.

An image forming apparatus includes a plurality of pipes through which developer passes. The developer is conveyed from a plurality of developer containers to a plurality of developing units. The plurality of pipes includes a first pipe that extends to a first receiving port of a first developing unit from a first communication port of an attachment portion to and from which a first developer container is attachable and detachable. The developer from the first discharge port of the first developer container passes through the first pipe. The first developer container and the first pipe are provided respectively, in a second direction orthogonal to a first direction, at a position closest to a first end surface among the plurality of developer containers and the plurality of pipes. At least a part of the first communication port overlaps the first receiving port when viewed in the first direction.

A scanning optical device includes a polygon mirror, an optical box accommodating the polygon mirror, and a cover covering an opening of the optical box. On an opposite surface of the cover, a plurality of ribs projected toward the polygon mirror are formed. As viewed in a rotational axis direction of the polygon mirror, the ribs are disposed so as to have rotational symmetry about a rotational axis, extended from the axis toward a circumscribing circle of the polygon mirror, and disposed at positions apart from a distance in upstream or downstream side in the rotational direction to imaginary lines, of the same number as that of the ribs, having rotational symmetry about the rotational axis. Each of ribs has a lengthy shape parallel to the corresponding imaginary line, one end portion thereof is disposed outside and the other end portion thereof is disposed inside the circumscribing circle.

An optical writing device includes: a light beam generator that emits a light beam; and an optical scanner that reflects the light beam emitted from the light beam generator and scans the light beam in a one-dimensional direction, the optical writing device variably controlling an amount of the light beam within a one-dimensional scan based on a light-amount unevenness correction value. The light-amount unevenness correction value when the optical writing device is reused is determined from specific information specific to the optical writing device and use information regarding use of the optical writing device.

A light scanning apparatus according to the present disclosure includes a deflecting unit configured to deflect a light flux from a light source to scan a surface in a main scanning direction, and a first optical system configured to guide the light flux deflected by the deflecting unit to the surface to be scanned, in which a width of the light flux immediately before being incident on a first deflecting surface of the deflecting unit is smaller than a width of the first deflecting surface in a main scanning cross section, and only a part of the light flux incident on the deflecting unit is deflected toward the surface to be scanned by the first deflecting surface when the first deflecting surface is at a first angle in the main scanning cross section.

An image forming apparatus includes an image bearing member, a transfer member, an acquiring portion, an applying portion, and a controller. When a transfer voltage is subjected to constant-voltage control so that the transfer voltage applied to the transfer member by the applying portion is substantially constant, in a case that the transfer voltage, when a toner amount used for a toner image is a first toner amount, is a first voltage, the controller controls the applying portion so that the transfer voltage is a second voltage lower in absolute value than the first voltage in a case that the toner amount is a second toner amount greater than the first toner amount. The acquiring portion acquires toner amount information on the toner amount for each toner image transferred onto a single recording material.

An image forming apparatus is configured such that a second photosensitive drum is disposed between a first toner container and a first developing container in a first direction, a part of a first pipe is disposed to pass a region outside a light path of a laser beam radiated from a laser scanner to the second photosensitive drum in a second direction, and at least a part of a wall is a region between the part of the first pipe and the light path in the second direction and is disposed in a region overlapping with the light path when viewed in a direction of a rotational axis of the second photosensitive drum.

An image forming apparatus includes a photoconductor drum, an exposure device, a development device, and a controller. The exposure device irradiates the photoconductor drum with a light beam and thereby forms an electrostatic latent image. The development device causes toner to adhere to the electrostatic latent image and thereby generates a toner image. The controller controls the exposure device. Further the exposure device includes a polygon mirror, a polygon motor, a mark detector, and an actuator. The polygon mirror is configured to scan the light beam. The polygon motor is configured to rotate the polygon mirror. The mark detector is configured to detect a mark attached to a motor axis of the polygon motor. The actuator is configured to be enabled to move the mark detector. Furthermore, the controller moves the mark detector to a position corresponding to an operation condition of the exposure device using the actuator.

An image forming apparatus includes an image bearing member, a transfer member, an acquiring portion, an applying portion, and a controller. When a transfer voltage is subjected to constant-voltage control so that the transfer voltage applied to the transfer member by the applying portion is substantially constant, in a case that the transfer voltage, when a toner amount used for a toner image is a first toner amount, is a first voltage, the controller controls the applying portion so that the transfer voltage is a second voltage lower in absolute value than the first voltage in a case that the toner amount is a second toner amount greater than the first toner amount. The acquiring portion acquires toner amount information on the toner amount for each toner image transferred onto a single recording material.

An image forming apparatus includes an exposure device, a driving control unit, and an exposure control unit. The exposure device is configured to expose a photoconductor drum with light while scanning the light and thereby form an electrostatic latent image. The driving control unit is configured to generate a secondary-scanning-directional reference signal. The exposure control unit is configured to generate a secondary-scanning-directional synchronization signal in synchronization with a primary-scanning-directional reference signal correspondingly to an edge of the secondary-scanning-directional reference signal, and control the exposure device and thereby cause the exposure device to form an electrostatic latent image corresponding to an image signal in synchronization with the secondary-scanning-directional synchronization signal. Further, the driving control unit generates the secondary-scanning-directional reference signal with a waveform that includes at least one additional edge within a predetermined period from the edge.