An image processing apparatus includes a reading unit and a controller. The reading unit radiates light to a target from two directions with different angles and reads images of the target. The controller performs, when controlling the reading unit to acquire the two images of the target, control such that a resolution of the image read by radiating the light to the target from one of the two directions is lower than a resolution of the image read by radiating the light to the target from the other one of the two directions.

A reading device includes: a light source that irradiates a subject with scanning light; a light receiving section that receives reflection light from the subject; and circuitry to: control the light source to switch on and off of the scanning light; control the light receiver to receive the reflection light from the subject for a predetermined acquisition time at a predetermined acquisition interval so as to acquire data; and calculate a difference between the data acquired while the scanning light is switched on and the data acquired while the scanning light is switched off. The predetermined acquisition time and the predetermined acquisition interval are set such that the acquisition time or a total time of the acquisition time and the acquisition interval become an integer multiple of a fluctuation cycle of a fluctuation factor.

An optical information reader includes a reflective member that reflects illumination light emitted from an illuminant toward a reading surface, and an image former ensured to present an imaging target held over the reading surface within an imaging region of an imager. The imaging region includes a first imaging region defined between the image former and the reading surface, and a second imaging region defined between the reading surface and the reflective member so as to be continuous to the first imaging region when light is internally reflected on the reading surface inside the housing. The reflective member is arranged outside the first imaging region, while the illuminant, the imager and the image former are arranged outside the second imaging region. The illuminant emits illumination light toward a reflecting surface of the reflective member in the second imaging region.

An image processing apparatus includes a reading unit and a controller. The reading unit radiates light to a target from two directions with different angles and reads images of the target. The controller performs, when controlling the reading unit to acquire the two images of the target, control such that a resolution of the image read by radiating the light to the target from one of the two directions is lower than a resolution of the image read by radiating the light to the target from the other one of the two directions.

A detection apparatus includes a second detection unit configured to detect lowering of a light reflectance of a reflection portion based on an output value based on light received by a light receiving portion while an object is moving on a conveyance path, without depending on at least a part of output values output based on light received by the receiving unit while the object is stopped on the conveyance path.

An illuminating device capable of stably illuminating an irradiated object such as a document while suppressing light loss with a simply structure is provided. An LED array and a reflective plate are disposed sandwiching a slit (St) through which light reflected by a document MS passes and a light-guiding member is disposed on the side of the LED array. The light-guiding member includes a direct emission unit disposed between an illumination range y centered on a document reading position and the LED array and an indirect emission unit disposed between the reflective plate and the LED array, a light incidence face of the direct emission unit and a light incidence face of the indirect emission unit are disposed at mutually different position around the LED array, and the LED array is disposed on a side of an interior angle formed by the light incidence faces.

An optical information reader includes a reflective member that reflects illumination light emitted from an illuminant toward a reading surface, and an image former ensured to present an imaging target held over the reading surface within an imaging region of an imager. The imaging region includes a first imaging region defined between the image former and the reading surface, and a second imaging region defined between the reading surface and the reflective member so as to be continuous to the first imaging region when light is internally reflected on the reading surface inside the housing. The reflective member is arranged outside the first imaging region, while the illuminant, the imager and the image former are arranged outside the second imaging region. The illuminant emits illumination light toward a reflecting surface of the reflective member in the second imaging region.

A sheet medium conveying device conveys a sheet medium in which position detection marks are provided at regular intervals in a medium conveying direction in which the sheet medium is conveyed. The sheet medium conveying device includes a controller that controls conveyance of the sheet medium. The controller selects one of a first standby position and a second standby position located downstream of the first standby position in the medium conveying direction, and conveys the sheet medium to the selected standby position and puts the sheet medium on standby.

An image reading device has a document placement stage, a light source unit, and a sensor unit. The light source unit has a first light source part having a first light source at one end in the main scanning direction and a first light guide, a second light source part having a second light source at the other end in the main scanning direction and a second light guide, a first board where the first light source is mounted, and a second board where the second light source is mounted. The first and second boards each have a board base, a mounting part where the first or second light source is mounted, and a reflection face formed next to the first or second light source. The reflection faces of the first and second board faces face, to overlap the facing faces of the second and first light guides.

A reading device includes: a light source that irradiates a subject with scanning light; a light receiving section that receives reflection light from the subject; and circuitry to: control the light source to switch on and off of the scanning light; control the light receiver to receive the reflection light from the subject for a predetermined acquisition time at a predetermined acquisition interval so as to acquire data; and calculate a difference between the data acquired while the scanning light is switched on and the data acquired while the scanning light is switched off. The predetermined acquisition time and the predetermined acquisition interval are set such that the acquisition time or a total time of the acquisition time and the acquisition interval become an integer multiple of a fluctuation cycle of a fluctuation factor.