An illumination apparatus includes a light source and an elongated light guide, wherein the light guide includes an emission surface that emits light from the light source and a reflection surface that reflects the light to the emission surface, the reflection surface includes a plurality of diffusion portions that diffuse the light, the diffusion portions have a shape of part of a sphere recessed from the reflection surface, a depth of the diffusion portions from the reflection surface is equal to or greater than 16.5% and equal to or smaller than 50% of a diameter of the sphere, and a width of the diffusion portions is equal to or greater than 0.1 mm and equal to or smaller than 50% of a width of the reflection surface.

An image sensor module includes a light source unit that emits a linear light beam elongate in a primary scanning direction to an object to be read, and a lens unit including an incidence surface and an output surface oriented opposite to each other. The lens unit is configured to receive light from the object through the incidence surface and output the light through the output surface. The module also includes a sensor IC that receives the light outputted from the output surface, a housing that holds the light source unit and the lens unit, and a support member that supports the lens unit such that the incidence surface is located more distant from the sensor IC than the output surface in a secondary scanning direction. The support member includes a reflection surface that reflects the light from the object toward the incidence surface.

An apparatus has an optical scanner generating image signals, and a processor electrically connected to the optical scanner. The processor converts the electrical signals into image data. Also, a printing engine is electrically connected to the processor, and a light guide is positioned between the printing engine and the optical scanner. The optical scanner generates operating condition signals when optically scanning the light guide. The optical scanner transmits the operating condition signals to the processor, and the processor adjusts operations of the printing engine based on the operating condition signals.

There is provided a scanner including: a first light source that generates light of a first wavelength; a mark that emits light in a case where light of the first wavelength is received; a deviation calculation section that calculates a deviation between a plurality of sensors based on sensor outputs acquired in such a way that the sensors detect light emitted from the same mark; a second light source that generates light which does not include light of the first wavelength; and an image generation section that generates image data based on the sensor outputs, acquired in such a way that the plurality of sensors detect light acquired when light from the second light source is stuck on and is reflected in the document, and the deviation.

A light irradiation device includes a light source, a light guide member, and a holding member. The light guide member includes an incident surface, an exit surface, and a held surface. The incident surface has an elongated shape in a main scanning direction and faces a light emitting surface of the light source. The light guide member includes a securing structure in each of both end portions in the main scanning direction, which are out of a light guide area of the light guide member. The securing structure in one end portion is an engagement lug structure protruding to penetrate into a through-hole of the holding member, including a lug on a leading end, and engaging the holding member. The securing structure on another end portion is a fastening structure having a fastening hole penetrated with a fastening member and being secured to the holding member with the fastening member.

In a reading device, a light transmissive member has a front surface on which an original is placed. A peripheral member is adjacent to the light transmissive member, and includes a back surface in which a reference hole is formed. The reference hole includes a first edge and a second edge intersecting with each other. A reading sensor faces the back surface of the light transmissive member and the back surface of the peripheral member. The controller controls the reading sensor to read a reading range including the reference hole to obtain a read image, and determines a reference position in the reading range based on the read image. The reference position is determined to an intersection between the first edge and the second edge. The controller sets a reading start position based on the reference position.

An imaging device includes a light source unit located so as to be inclined with respect to a medium conveying surface or a medium placing surface. The light source unit includes a light emitting element, a light guide provided with the light emitting element on a first end surface side, to guide light emitted from the light emitting element in a predetermined direction, and emit the light toward the medium from an emitting surface extending in the predetermined direction, and a reflector located around the light guide other than the emitting surface. The light guide includes a light diffusing surface on an opposite side to the emitting surface. The reflector does not cover a second end surface opposite to the first end surface of the light guide. A medium side surface of the reflector is located so as to protrude from the second end surface of the light guide.

Provided is an image sensor lighting unit including at least one light guide extending in a main scanning direction; a first light source group facing a first end surface of at least two end surfaces of the at least one light guide in the main scanning direction; and a second light source group facing a second end surface of the at least two end surfaces. The first light source group includes a first light source that emits light having a predetermined wavelength band. The second light source group includes a second light source that emits light having the wavelength band. An X-coordinate of the first light source in a corresponding XY-coordinate system is equal in absolute value to an X-coordinate of the second light source in a corresponding XY-coordinate system, with the at least one light guide viewed from the first end surface side in the main scanning direction.

An imaging device includes a light source unit located so as to be inclined with respect to a medium conveying surface or a medium placing surface. The light source unit includes a light emitting element, a light guide provided with the light emitting element on a first end surface side, to guide light emitted from the light emitting element in a predetermined direction, and emit the light toward the medium from an emitting surface extending in the predetermined direction, and a reflector located around the light guide other than the emitting surface. The light guide includes a light diffusing surface on an opposite side to the emitting surface. The reflector does not cover a second end surface opposite to the first end surface of the light guide. A medium side surface of the reflector is located so as to protrude from the second end surface of the light guide.

An image reading apparatus (1) includes image sensors (20A, 20B). The image sensor (20A) includes light guides (21A, 22A) guiding light to a reading target (M), a lens body (8A) forming an image of reflected light derived from the light guided by the light guides (21A, 22A) and reflected from the reading target (M), light receiving elements (11A) converting the image of reflected light formed by the lens body (8A) into electrical signals, and a controller (14A) controlling exposure times of the light receiving elements (11A). The image sensor (20B) includes a lens body (8B) forming an image of transmitted light derived from the light guided by the light guide (22A) and transmitted through the reading target (M), light receiving elements (11B) converting the image of transmitted light formed by the lens body (8B) into electrical signals, and a controller (14B) controlling exposure times of the light receiving elements (11B).