An image reading device includes a plurality of conveyance rollers to convey a sheet, a motor to drive the plurality of conveyance rollers, an image reading unit to read an image of the sheet, a control device to perform a stop control that stops the sheet in a course of a conveyance path, and a clutch to transmit a driving force of the motor. A first conveyance roller group includes at least one of the plurality of conveyance rollers upstream from a leading end of the sheet stopped by the stop control in a conveyance direction, to which the driving force is transmitted via the clutch. A second conveyance roller group includes at least one of the plurality of conveyance rollers downstream from the leading end of the sheet stopped by the stop control in the conveyance direction, to which the driving force is transmitted without the clutch.

An image reading apparatus according to an embodiment includes an image reading unit that generates reference data by reading a reference surface and generates image data by reading a sheet. A reference plate includes the reference surface for generating the reference data for shading correction of the image reading unit and a background surface for background of a sheet to be read to generate the image data. A control unit controls the positions of the image reading unit and the reference plate to be at a first position relative to each other when the reference data is to be generated and at a second position relative to each other when the image data is to be generated. The second position is different from the first position. A shading correction unit performs the shading correction in the image reading unit based on the generated reference data.

An image reading device includes a light applying unit that applies light from a light source to a recording medium, a detecting unit that detects the light reflected by the recording medium, a holding member that is movable in a first scanning direction of the light applying unit and holds a calibration member to which the light from the light applying unit is applied, a shaft member that extends in the first scanning direction through the holding member and guides the movement of the holding member in the first scanning direction, and a restricting member that extends in the first scanning direction and restricts rotation of the holding member about the shaft member.

A sensor mounting structure includes a positioning member, a holding member, and a biasing member. The positioning member is a mounting reference of a sensor. The holding member is attachable to and detachable from the positioning member so as to form a space in which the sensor is disposed with respect to the positioning member. The biasing member includes an arched part which is overhung between a pair of engaging parts engaging with the holding member. The biasing member, while the holding member is attached to the positioning member, elastically deforms the arched part that is sandwiched between the holding member and the sensor that is disposed in the space so as to bias the sensor to the positioning member.

In one example, an apparatus includes a transparent platen to receive a document to be scanned. The transparent platen includes a scan line, an ingress edge positioned prior to the scan line in the document path, and a chamfered egress edge positioned subsequent to the document path. A light source is positioned to illuminate the document with light while the document passes across the scan line, and a focusing mechanism is positioned to focus a portion of the light that is reflected by the document onto a sensor that senses the portion of the light.

Provided is a reading apparatus capable of preventing luminance unevenness in a reading range by correcting shading data. An original reading unit of a reading apparatus configured to read an image on an original includes a row of light receiving elements aligned in a main scanning direction orthogonal to a direction in which the original is conveyed. The reading apparatus generates shading data used in shading correction, based on the result of reading a white reference board via the original reading unit.

An image forming device, which is included in an image forming apparatus, includes an image reader, a sheet conveyance passage, a transparent body, an opposing body, and multiple curved opposing portions. The image reader is configured to read an image formed on a target object. The sheet conveyance passage is a passage through which the target object is conveyed. The transparent body is disposed between the sheet conveyance passage and the image reader. The opposing body is disposed facing the transparent body on a side opposite the image reader. The multiple curved opposing portions have respective outwardly curving reference planes. The multiple curved opposing portions are sequentially switched and located at a predetermined image reading position at which the multiple curved opposing portions face the transparent body with a gap through which the target object passes the predetermined image reading position.

An image reading apparatus according to an embodiment includes an image reading unit configured to generate reference data by reading a reference surface and to generate image data by reading a sheet. A reference unit has a reference surface. A shading correction unit determines whether a portion of the reference surface includes a contaminant based on image data generated by the image reading unit reading the portion of the reference unit. When the portion of the reference surface is determined to not include a contaminant, the shading correction unit generates reference data based on the image data generated by the image reading unit reading the portion of the reference surface determined to not include a contaminant.

An image reading device includes a plurality of conveyance rollers to convey a sheet, a motor to drive the plurality of conveyance rollers, an image reading unit to read an image of the sheet, a control device to perform a stop control that stops the sheet in a course of a conveyance path, and a clutch to transmit a driving force of the motor. A first conveyance roller group includes at least one of the plurality of conveyance rollers upstream from a leading end of the sheet stopped by the stop control in a conveyance direction, to which the driving force is transmitted via the clutch. A second conveyance roller group includes at least one of the plurality of conveyance rollers downstream from the leading end of the sheet stopped by the stop control in the conveyance direction, to which the driving force is transmitted without the clutch.

A document reading device (20) includes: a document conveyance section (6) and a document reading device (5). A conveyed document reading region (161b) has: a document discharge guide (51) arranged downstream of an image reading position (163a) in a document conveyance direction; and a transparent reading sheet (52) provided along a surface of the contact glass (161) and a surface of the document discharge guide (51), the document conveyance section (6) has a reading guide (62) forming a document conveyance path oppositely to the conveyed document reading region (161b), and the reading guide (62) has, on part of a surface opposing the conveyed document reading region (161b), a black reference member (620) optically read by an image reading section (163) for the purpose of correcting black reference data of an image of the document conveyed by the document conveyance section (6) and read by the document reading device (5).