A reading module has a light source, an optical system, and a sensor. The optical system images, as image light, reflected light of light radiated from the light source to a document. In the sensor, the image light imaged by the optical system is converted into an electrical signal. The optical system has a mirror array and an aperture stop portion. In the mirror array, reflection mirrors are coupled together in an array in the main scanning direction. The aperture stop portion has a first aperture adjusting the amount of the image light reflected from a reflection mirror and a second aperture shielding stray light entering the first aperture from an adjacent reflection mirror. Between the first and second apertures, a reflection reduction mechanism is provided that reduces reflection, toward the first aperture, of light other than the image light traveling from the second to first aperture.

A controller of an image reading apparatus is configured to cause the reading device to read an image on an original with moving a reading location from a first position to a second position, after reading the image on the original with moving the reading location from a third position to the first position, the third position being a position between the first position and the second position and spaced from the first position by a particular distance and determining a width of the original in the main scanning direction. The controller is configured to further move the reading location from the second position to the first position, and detect an instruction to continue reading a subsequent original during a period before the reading location reaches the third position. When the instruction is detected, the controller stops moving the reading location when it reaches the third position.

A lens array includes a flat plate-shaped base part, a plurality of lenses, a plurality of columnar light guiding parts and a plurality of light shielding parts. The lenses are formed on one surface of the base part. The columnar light guiding parts are formed on another surface of the base part at points corresponding to the lenses. The light shielding parts are formed at least on lateral surfaces of the light guiding parts.

An image reading apparatus includes a light source that emits light in a main scanning direction to a subject to be read, a light receiving unit that receives light reflected by the subject to be read, and an optical system that images the light reflected by the subject to be read and guides the light to the light receiving unit. The optical system includes a reflector mirror that reflects the light reflected by the subject to be read, and an optical element that is disposed adjacent to the reflector mirror and images the light reflected by the subject to be read. The optical element is held by the reflector mirror.

An imaging device for an additive manufacturing system is provided. The additive manufacturing system includes a material. The imaging device includes a high resolution imaging bar including at least one detector array, and an imaging element positioned between the at least one detector array and the material. The high resolution imaging bar is displaced from the material along a first direction and extends along a second direction. The high resolution imaging bar is configured to generate an image of a build layer within the material.

An image reading device can easily increase or improve the depth of field. The image reading device includes a lens array (1) including lenses (2) arrayed in a main scanning direction, a sensor array (4) including sensor elements (4) arrayed in the main scanning direction to receive light converged by the lenses (2), and an overlap preventer located between the lens array (1) and the sensor array (4) to prevent an overlap of images formed by the lenses (2). The overlap preventer includes a slit assembly (5) including at least one specific-light blocker or optically transparent columns (13).

A first image reading chip for reading an image of a first surface of a medium includes a first pixel portion that outputs a first pixel signal, a first output circuit that outputs a signal based on the first pixel signal, and a first output selection unit that selects a first drive capability as a drive capability of the first output circuit, and a second image reading chip for reading an image of a second surface of a medium includes a second pixel portion that outputs a second pixel signal, a second output circuit that outputs a signal based on the second pixel signal, and a second output selection unit that selects a second drive capability as a drive capability of the second output circuit.

An exposure apparatus according to an embodiment includes: a board that includes a first surface on which a light emitting element is arranged and a second surface opposite to the first surface; a lens member on which light from the light emitting element is incident; a holder that holds the lens member; and an insulation sheet formed of an insulation material. The board includes an abutment part provided on a second surface of the board. The insulation sheet is fixed to the holder while being in contact with the abutment part.

An optical scanning device includes a light source having plural light emitting portions, a deflection unit that deflects and scans plural light beams emitted from the light source in a main scanning direction, and plural optical element groups disposed between the light source and the deflection unit and including an optical element having a negative refractive power along a sub-scanning direction intersecting the main scanning direction. An interval in the sub-scanning direction of the plural light beams is adjusted by tilting the optical element having the negative refractive power on an axis along the main scanning direction.

Provided is a scanner having sixteen or fewer sensor chips capable of scanning an A4 document; an optical unit that reduces and focuses an image of an A4 document on the sensor chips; and a generator that synthesizes images of the A4 document read by the sensor chips, and generates image data.