An image reading optical system includes an image reading portion, multiple light reflection portions, and a diaphragm. The image reading portion includes an array of reading elements that read incident light. The light reflection portions reflect light traveling from a readable object to the image reading portion. The diaphragm regulates light traveling from a first one of the light reflection portions to a subsequent one of the light reflection portions in a specific direction. The diaphragm includes a first light shielding portion and a second light shielding portion disposed at different positions in a travel direction of the light with respect to the first one of the light reflection portions to block part of the light. The first light shielding portion and the second light shielding portion are located in substantially a common plane. The first light shielding portion is disposed along an optical axis of light incident on the first one of the light reflection portions.

A reading module of the present disclosure is provided with a light source, an optical system, and a sensor. The optical system images, as reading light, reflected light of light radiated from the light source to an illumination object. The sensor converts the reading light imaged by the optical system into an electric signal. The optical system is provided with a mirror array in which a plurality of reflection mirrors are disposed in an array in a prescribed direction and a plurality of aperture stop portions that adjust an amount of the reading light. Each of the reflection mirrors is disposed at a prescribed distance from an adjacent one of the reflection mirrors in a prescribed direction.

An image forming apparatus comprises a first temperature detector to detect a temperature of a first portion of an optical scanning device in a printer. The first portion is proximate to a heat generating element in the optical scanning device. A second temperature detector is provided to detect a temperature of a second portion of the optical scanning device, which is farther from the heat generating element than the first portion. A controller is configured to perform alignment control for correcting a color positional shift of the printer when either a detected temperature change of the first portion is greater than or equal to a first threshold value or a detected temperature change of the second portion is greater than or equal to a second threshold value.

Provided is an image forming apparatus capable of accurately returning a carriage to a home position without having to turn ON a light source in the process of returning the carriage to the home position. A first reading-position-detection plate is arranged inside of a reading width of a line sensor and outside of a document-image-reading width. A second color region has a length that gradually increases in the main scanning direction as going away from the home position of the carriage. A reading-position-detecting unit detects the length in the main scanning direction of the second color region on the basis of output from the line sensor. A movement-distance-converting unit converts this length to a movement distance to the home position. A movement-control unit causes the carriage to move toward the home position just the movement distance.

In accordance with an embodiment, a lens mirror array includes a plurality of optical elements integrally connected in a first direction. Each optical element includes an incident side lens surface through which light enters the optical element, a ridge located at an edge of the incident side lens surface, a reflection surface on which light incident on the incident side lens surface is reflected, an exit side lens surface through which light reflected by the reflection surface exits the optical element, and a groove surrounding the reflection surface except for a portion adjacent to the ridge, the portion adjacent to the ridge connecting to an adjacent optical element in the plurality of optical elements.

An optical scanning device includes light sources, a deflector deflecting light beams emitted from the light sources, a first lens transmitting the light beams deflected by the defector, and second lenses guiding the light beams transmitted from the first lens to respective surfaces to be scanned. The second lenses are arranged so that a first incident position of a first light beam emitted by a first light source and entering one of the second lenses is closer to the respective surface to be scanned along an optical axis of the first lens than a second incident position of a second light beam emitted by a second light source and entering another of the second lenses, and an incident angle of the second light beam with respect to the optical axis along a deflection direction by the deflector is greater than the incident angle of the first light beam.

A fixing device includes a circulating member, a pressure member, a pad material, a heater, a reflector, and a heat conductor. The circulating member includes an annular peripheral wall that is circularly movable. The pressure member is arranged to face an outer peripheral surface of the circulating member and forms a nip with the circulating member. The pad material abuts on an inner peripheral surface of the circulating member at a nip portion of the circulating member. The heater is arranged inside the circulating member and heats the circulating member. The reflector is inside the circulating member and reflects radiant heat of the heater to the circulating member. The heat conductor connects an area covering a pressed portion of the pad material against the circulating member. The reflector is formed of a material having higher thermal conductivity than the pad material.

An information detecting device detects information from a target. The information detecting device includes processing circuitry. The processing circuitry is configured to perform a first information acquisition operation of acquiring first information from a target criterion, a second information acquisition operation of acquiring second information from the target, and an information conversion operation of converting the second information acquired by the second information acquisition operation, into third information, with the first information acquired by the first information acquisition operation, the third information having a dimension different from respective dimensions of the first information and the second information; and perform control such that an information-acquisition condition in the first information acquisition operation is identical to an information-acquisition condition in the second information acquisition operation.

A reading module has a light source, an optical system having a mirror array and an aperture stop portion, a sensor in which a plurality of image regions where the image light is converted into an electrical signal are arranged; a housing; and a light-shielding wall shielding stray light striking the image regions. In the mirror array, a plurality of reflective mirrors whose reflection surfaces are aspherical concave surfaces are coupled together in an array in the main scanning direction. The optical system is fixed to on the case housing at one point in the main scanning direction, and the light shielding walls are arranged at a positions displaced deviated by a predetermined amount from boundaries between the image regions in the direction opposite to the fixed side of the optical system.

An image forming apparatus includes a photosensitive member, a light source, a deflecting unit, a storing unit, a correcting unit, and a light source driving portion. Magnification correction data is determined using a quadratic function of a variable representing a scanning position with respect to a scanning direction. Coefficients of two quadratic functions corresponding to adjacent two regions included in a plurality of scanning regions are set so that a differential value calculated at the variable corresponding to a boundary of the two regions by a differential of the quadratic function for one region and a differential value calculated at the variable corresponding to the boundary of the two regions by a differential of the quadratic function for the other region are equal to each other.