An image reading apparatus for reading image information from a sheet includes a cover unit, a sheet feeding member, a conveying guide, and a reading unit including a transparent member and a reading portion. The cover unit is rotatable between a closed position where the cover unit forms a sheet conveying passage in cooperation with the conveying guide and an open position where the sheet conveying passage is open. In a state in which the cover unit is positioned in the closed position, the transparent member is exposed to an outside of the image reading apparatus by rotation of the conveying guide and the reading unit.

An image reading apparatus includes a transparent member, reading portion, a pattern, and a processor. The processor extracts a frequency component in an image of the pattern read by the reading portion in a period in which the reading portion reads an image of an original placed on the transparent member while moving in a first direction. The processor calculates a frequency component from the extracted frequency component in another position different from the position, in which the pattern is provided, with respect to the second direction crossing the first direction. The processor converts the calculated frequency component in the above-described another position into a time-series component. The processor corrects an image corresponding to the above-described another position by using the converted time-series component in the above-described another position.

An image reading apparatus for reading image information from a sheet includes a cover unit, a sheet feeding member, a conveying guide, and a reading unit including a transparent member and a reading portion. The cover unit is rotatable between a closed position where the cover unit forms a sheet conveying passage in cooperation with the conveying guide and an open position where the sheet conveying passage is open. In a state in which the cover unit is positioned in the closed position, the transparent member is exposed to an outside of the image reading apparatus by rotation of the conveying guide and the reading unit.

A scanner includes: a first body having a window and a guide structure; a transparent platen connected to the first body to cover the window; a first sheet disposed on the transparent platen and in the window; a second sheet fixedly disposed on the transparent platen, in the window and on the guide structure, wherein the first sheet is thicker than the second sheet to form a cliff-sheet type guiding structure as a first part of a transporting passage; a scanning module disposed in the first body; a second body having a second part of the transporting passage; and a transporting mechanism being disposed in the second body and transporting a document along the transporting passage, so that the scanning module scans an image of the document through the window.

An image reading device includes: a scanner glass; photo-sensors arranged at intervals in a main scanning direction to read a document conveyed in a sub-scanning direction; an adjuster that adjusts the size of an overlapping area between a first and second image obtained by neighboring photo-sensors, the overlapping area constituting a first area of the first image and a second area of the second image; a superimposing portion that shifts either one of images of the first and second area to the other one; a judgment portion that judges whether the images having different focal depths exist based on the degree of matching between the first and second area; and a detector that detects a foreign body on the scanner glass platen by detecting a continuous image stretching in a document conveying direction in both of the images having different focal depths, if the images having different focal depths exist.

An image reading apparatus includes an LED light source, a CCD sensor receiving light reflected from a document irradiated with light from the LED light source, a fan, and a frame housing the LED light source, the CCD sensor and the fan. The fan circulates air in a substantially sealed space formed by the frame. Thus, temperature difference in the image reading apparatus can be reduced while not degrading dust-proof property of the apparatus, and efficient heat radiation to the outside becomes possible. Thus, variation of sensitivity of CCD sensor, deviation of point of focus of image forming system and deviation of reading position caused by temperature increase can be prevented.

A scanner includes a scanning module. The scanning module has a scan channel and a scanning glass. A lower surface of the scanner is defined as a bottom wall of the scan channel. The scanning glass is positioned above the scan channel. A bottom surface of the scanning glass is defined as a top wall of the scan channel. The lower surface of the scanner has an upstream turn connected between an upstream section and a middle section of the lower surface of the scanner, the middle section of the lower surface of the scanner is parallel with the bottom surface of the scanning glass.

A scanner includes a lower unit and an upper unit. The lower unit includes a first document table on which a first document is to be placed. The upper unit includes a second document table on which a second document is to be loaded and a document feed path through which the second document is to be picked up from the second document table fed, the upper unit being coupled to the lower unit to pivot between a closed position in which the first document table is covered and an open position in which the first document table is exposed. The upper unit further includes a reading unit to read an image from the first document and the second document by performing flatbed scanning on the first document and document feed scanning on the second document.

An image reading apparatus reads an image of a sheet conveyed from an image forming apparatus. The image reading apparatus includes a transparent member including a first surface disposed on a first side on which the sheet is conveyed and a second surface disposed on a second side opposite to the first side, an image reading portion disposed on the second side and configured to read the image of the sheet at a reading position through the transparent member, an elastic member disposed to abut against the second surface of the transparent member and configured to press the transparent member toward the first side, and a guide disposed upstream of the reading position and configured to guide the sheet to the reading position. A downstream end of the guide contacts with the first surface of the transparent member and presses the transparent member toward the second side.

An image reading apparatus includes a main body part and an openable part. On an upper surface of the main body part, a first reading surface, a second reading surface and a first guide part arranged between the two reading surfaces are provided. When a direction parallel to a direction in which an original passes over the second reading surface is defined as a first direction, and a direction parallel to the second reading surface and orthogonal to the first direction is defined as a second direction, on the upper surface, a positioning convex part having a curved surface curved downward when viewed in the second direction is provided on an extended line of the first guide part. On a lower surface of the openable part, a positioning concave part having two inclined surfaces respectively contacting the curved surface when viewed in the second direction is provided.