An image forming apparatus includes plural photosensitive members, a scanner unit for scanning the photosensitive members, and a fixing unit for fixing toner images. The scanner unit includes a rotatable polygonal mirror for reflecting laser beams emitted in correspondence to respective photosensitive members, reflecting members for reflecting the laser beams, and a box for accommodating the polygonal mirror and the reflecting members. The box includes plural outlets for the laser beams. Of the reflecting members, first and second reflecting members reflect laser beams toward corresponding first and second outlets respectively positioned farthest from and closest to the fixing unit. A distance between the first outlet and its corresponding photosensitive member is longer than a distance between the second outlet and its corresponding photosensitive member, whereas a distance between the first reflecting member and the polygonal mirror is shorter than a distance between the second reflecting member and the polygonal mirror.

A first supporting unit configured to movably support, in a direction intersecting with A length direction of A first reflecting mirror, an end of the first reflecting mirror in the length direction of the first reflecting mirror; a second supporting unit configured to movably support, in a direction intersecting with the length direction of a second reflecting mirror, an end of the second reflecting mirror in the length direction of the second reflecting mirror; a first drive source; a first transmission unit configured to transmit, when the first drive source provides a drive source in a first direction, the movement of the first drive source to a first supporting unit; and a second transmission unit configured to transmit, when the first drive source provides a drive source in a second direction, a movement of a second drive source to the second supporting unit.

An exposure device includes: a substrate that includes a plate-shaped main body that extends in one direction, a plurality of light emitting elements that are mounted on one surface of the main body, and a heating element that is mounted on the other surface of the main body and generates heat in accordance with light emission of the light emitting element; a housing that extends in the one direction, has a frame shape in which a through hole is formed, and to an inside of the through hole of which the substrate is fixed so that a thickness direction of the main body is a penetrating direction of the through hole; and a first contact member that extends in the one direction, and is in contact with at least a portion of the heating element and the main body at a different position in the one direction.

An exposure device includes: a substrate that includes a main body extending in one direction, light emitting elements on one surface of the main body, and a heating element on the other surface which generating heat upon emission of the light emitting elements; a housing having a frame shape which a through hole, to an inside of which the substrate is fixed so that a thickness direction of the main body is a penetrating direction of the through hole; a facing member fixed to the housing and opposing to the other surface; and a contact member contacting to the facing member and the heating element. An injection portion to inject a soft member as the contact member is formed between the substrate and the facing member on the facing member or the housing. When viewed a substrate side through the injection portion, the contact member covers partially the heating element.

An exposure device includes: a substrate that includes a plate-shaped main body that extends in one direction, a plurality of light emitting elements that are mounted on one surface of the main body, and a heating element that is mounted on the other surface of the main body generates heat in accordance with a light emitting operation of the light emitting elements; a housing that includes resin and that extends in the one direction, has a frame shape in which a through hole is formed, and to an inside of the through hole of which the substrate is fixed so that a thickness direction of the substrate is a penetrating direction of the through hole; and a suppression member that extends in the one direction, is fitted in the through hole, and suppresses thermal deformation of the housing.

A light emitting device includes: a base that extends in one direction, and has an opening; plural light emitting units that are disposed to be displaced from each other in the one direction on the front surface side of the base, the light emitting units each including a support that extends in the one direction, and plural light sources that are disposed in the one direction on the support; and an air blowing unit that blows air toward the light emitting units through the opening.

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 light deflector includes a rotary polygon mirror and a motor to rotate the rotary polygon mirror. The rotary polygon mirror includes reflecting surfaces to reflect light emitted from a light source and a hole portion provided in a rotational axis direction. The motor includes a shaft portion in the hole portion and a support member supporting the rotary polygon mirror. The support member is fixed to, and coaxial with, the shaft portion, and includes an insertion portion in the hole portion. The rotary polygon mirror includes a protruded portion near the hole portion and protruding from at least one reflecting surface orthogonal to the rotational axis direction. The protruded portion includes a fitting portion fitted to the shaft portion or the support member and in which a portion continued from a hole portion surface is protruded toward the rotation center more than the surface forming the hole portion.

A reading device and an image forming apparatus are provided. The reading device includes an image reading device configured to read an image on a recording medium being conveyed, a background device serving as a background image when the image is read by the image reading device, and a foreign-object detector configured to compare a first read image obtained as the background device is read by the image reading device with a second read image obtained as the background device and the recording medium are read by the image reading device to detect an attached foreign object. The image forming apparatus includes the reading device and an image forming device.

A system includes a light source, a deflection unit configured to deflect a light beam having a wavelength λ emitted from the light source, and a lens unit including a plurality of lenses that focuses deflected light on a surface to be scanned, at least one lens among the plurality of lenses has a micro concavo-convex structure in an optical surface, and the optical surface having the micro concavo-convex structure has a transmittance distribution for the light beam having the wavelength λ according to a light quantity distribution of the deflected light and entering the lens unit.