An image forming apparatus includes a light emitting chip and at least one processor. The light emitting chip includes a plurality of light emitting elements, a DAC outputting a voltage corresponding to a setting value, and a circuit unit that supplies a current to the plurality of light emitting elements based on the voltage. At least one processor is configured to set the setting value such that one light emitting element included among the plurality of light emitting elements emits light of a predetermined amount, and correct image data pieces that respectively correspond to the plurality of light emitting elements based on first correction data for correcting amounts of light respectively emitted by the plurality of light emitting elements. The circuit unit supplies a current to each of the plurality of light emitting elements based on the corrected image data pieces.

An image forming apparatus includes an exposure unit that exposes a photoconductor; and an exposure support member that includes a support portion that detachably supports the exposure unit and is moved integrally with the exposure unit in a first direction orthogonal to an axial direction of the photoconductor, wherein the exposure unit includes a first engagement portion that is formed on an opposing portion facing the support portion of the exposure support member in the first direction so as to protrude toward the exposure support member and further formed to extend in the axial direction of the photoconductor orthogonal to a protruding direction, the exposure support member includes a second engagement portion that is formed on the support portion facing the exposure unit at a position corresponding to the first engagement portion and engages with the first engagement portion.

An exposure device irradiates a photoconductor with light on the basis of an exposure signal and thereby forms an electrostatic latent image. A toner amount calculating unit (a) determines a distribution pattern of the electrostatic latent image on the basis of the exposure signal, (b) determines an electric field variation level of a target pixel, (c) determines an electric field intensity of the target pixel on the basis of a value of the target pixel in the distribution pattern and the electric field variation level, and (d) determines a toner consumption amount corresponding to the electric field intensity. Further, using spatial filters independently of each other in a primary scanning direction and in a secondary scanning direction, the toner amount calculating unit determines the electric field variation level on the basis of (a) the distribution pattern or (b) the exposure signal.

An exposure device irradiates a photoconductor with light on the basis of an exposure signal and thereby forms an electrostatic latent image. A toner amount calculating unit (a) determines a distribution pattern of the electrostatic latent image on the basis of the exposure signal, (b) determines an electric field variation level of a target pixel, (c) determines an electric field intensity of the target pixel on the basis of a value of the target pixel in the distribution pattern and the electric field variation level, and (d) determines a toner consumption amount corresponding to the electric field intensity. Further, the toner amount calculating unit limits the electric field variation level to an uppermost value or less, the uppermost value corresponding to a value of the target pixel in the distribution pattern of the electrostatic latent image.

An image forming apparatus includes a main body, and a moving member movable with respect to the main body in a state of supporting an image forming portion. The moving member includes an image bearing member and an opening, and is movable between an inside position located inside of the main body and an outside position located outside of the main body, and in which at least a part of the image forming portion is removably mountable on the moving member as a cartridge. A shielding member is provided on the moving member and shields the opening. In addition, holding mechanism holds the shielding member in a shielding position corresponding to the opening while the moving member is moved between the inside position and the outside position, and holds the shielding member in a non-shielding position in which the opening is opened when the moving member is located in the inside position.

An image forming apparatus, including: a cartridge including a photosensitive drum and a regulation portion; a light emitting device configured to emit light from a light emission surface to the photosensitive drum; and a movement unit configured to reciprocate the light emitting device between an exposure position and a retracted position, wherein the regulation portion regulates a cleaning member, which includes a cleaning portion configured to rub and clean the light emission surface by a sliding movement of the cleaning member on the light emission surface of the light emitting device positioned at the retracted position so as to prevent the cleaning member from contacting the photosensitive drum and so as to bias the cleaning portion to prevent the cleaning portion from being separated from the light emission surface during the sliding movement of the cleaning member.

An image reading apparatus includes an image reading unit, a mounting portion, and a cover member. The cover member includes a first restricting portion, a lock portion, and an operation portion. The operation portion operated from outside the main unit is displaceable in a direction in which the lock portion deforms from the locking shape into the releasing shape. The mounting portion includes a second restricting portion and a part. The second restricting portion restricts displacement of the operation portion in the cover member mounted on the mounting portion in the second orientation. The part has a second aperture opening into the lock portion in the cover member mounted on the mounting portion in the second orientation from outside the main unit. The second aperture is an opening for the insertion of a tool for deforming the lock portion from the locking shape into the releasing shape.

An electrophotographic imager includes a photoconductive element, a charger, and a light source to expose areas of a charged surface of the photoconductive element to form a latent image. A development element is coupled relative to the photoconductive element to develop, via charged marking agent, the latent image on the photoconductive element. An exposure adjustment factor is selectively applied, prior to the exposing, to a first printable area of the latent image.

An optical device according to an embodiment includes a lens mirror array and a holder. The lens mirror array is opposed to a light emitting section. The lens mirror array includes a plurality of optical elements. The optical elements include incident-side lens surfaces, emission-side lens surfaces that emit incident light, and reflection surfaces that reflect incident light. A cross section orthogonal to a first direction of the lens mirror array has a constricted shape. The holder includes a slit having width smaller than width of both the ends in the cross section of the lens mirror array and larger than width of the center in the cross section and extending in the first direction. The holder holds the lens mirror array in a state in which a constricted portion in the center in the cross section of the lens mirror array is disposed in the slit.

A signal transmitting apparatus includes a first line that is provided in one of plural layers of a board and transmits a signal by superimposing the signal on an electric power line that supplies electric power; a coupling section in which the electric power line is coupled to the first line and the first line is branched; plural second lines that branch off in the coupling section and are provided in another layer different from the one layer; and a conductive layer that is provided between the one layer and the other layer. The conductive layer has an opening that encompasses the coupling section in plan view, and the coupling section has a coupling line that has a larger width than the first line and plural through-holes that connect the coupling line and the plural second lines through the opening of the conductive layer.