A reading device includes a position reference member and a reader. The position reference member has a reference pattern that includes a line extending in a prescribed direction. The position reference member is configured to relatively move in a direction orthogonal to the prescribed direction. The reader includes a plurality of sensor chips, each of the sensor chips including a plurality of pixels. The reference pattern corresponds to each of the sensor chips of the reader.

An image scanner includes a transparent plate, a scanning device, a driving device, a positioning member, a light absorbing portion and a white reference portion. The transparent plate has an original placing surface. The scanning device irradiates an original with light by means of a light source and scans reflected light from the original. The driving device reciprocates the scanning device along the transparent plate. The positioning member positions the original placed on the original placing surface of the transparent plate. The light absorbing portion, which is disposed on the original placing surface side of the positioning member and at substantially a central portion of the positioning member in moving directions of the scanning device, absorbs ambient light entering to the original placing surface side of the positioning member through the transparent plate. The white reference portion is provided to the original placing surface side of the positioning member.

Example implementations relate to streak compensation. Some examples may calibrate an initial gain for data from an optical element based on a scan of a first calibration target, obtain an image of a second calibration target from the optical element using the calibrated initial gain, and detect at least one streak in the image of the second calibration target. Some examples may also record data representing the at least one detected streak and may calibrate a final gain for the optical element based on the initial gain and the data representing the at least one detected streak.

A two-sided scanning device includes a first image scanning module, a second image scanning module, a first scanning background component, a first brightness calibration component, a second scanning background component, and a second brightness calibration component. When the second image scanning module moves relative to the first image scanning module to a scanning position, the second image scanning module drives the first scanning background component to move relative to the first image scanning module, so that the first image scanning module and the second image scanning module are aligned with the first scanning background component and the second scanning background component, respectively. Therefore, the first scanning background component and the second scanning background component can be scanning backgrounds for the first image scanning module and the second image scanning module to generate a scanning image of an object with a size corresponding to an actual size of the object.

There is provided an image reading apparatus including a first reading sensor provided in a first reading unit and configured to read one surface of the sheet, a second reading sensor provided in a second reading unit provided to face the first reading sensor and configured to read an image on the other surface of the sheet, a first background portion serving as a reading background of the first reading sensor, a second background portion serving as a reading background of the second reading sensor, and a moving portion configured to integrally move the first reading sensor and the second background portion, wherein the first reading unit includes a sensor case in which the first reading sensor is provided, and the sensor case is fixed to the apparatus main body.

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 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.

An image scanner includes a transparent plate, a scanning device, a driving device, a positioning member, a light absorbing portion and a white reference portion. The transparent plate has an original placing surface. The scanning device irradiates an original with light by means of a light source and scans reflected light from the original. The driving device reciprocates the scanning device along the transparent plate. The positioning member positions the original placed on the original placing surface of the transparent plate. The light absorbing portion, which is disposed on the original placing surface side of the positioning member and at substantially a central portion of the positioning member in moving directions of the scanning device, absorbs ambient light entering to the original placing surface side of the positioning member through the transparent plate. The white reference portion is provided to the original placing surface side of the positioning member.

An image scanner includes a transparent plate, a scanning device, a driving device, a positioning member, a light absorbing portion and a white reference portion. The transparent plate has an original placing surface. The scanning device irradiates an original with light by means of a light source and scans reflected light from the original. The driving device reciprocates the scanning device along the transparent plate. The positioning member positions the original placed on the original placing surface of the transparent plate. The light absorbing portion, which is disposed on the original placing surface side of the positioning member and at substantially a central portion of the positioning member in moving directions of the scanning device, absorbs ambient light entering to the original placing surface side of the positioning member through the transparent plate. The white reference portion is provided to the original placing surface side of the positioning member.

Example implementations relate to streak compensation. Some examples may calibrate an initial gain for data from an optical element based on a scan of a first calibration target, obtain an image of a second calibration target from the optical element using the calibrated initial gain, and detect at least one streak in the image of the second calibration target. Some examples may also record data representing the at least one detected streak and may calibrate a final gain for the optical element based on the initial gain and the data representing the at least one detected streak.