An image reading apparatus is capable of reducing glare that a user feels while PWM-controlling an LED and of detecting an original size in a principal scanning direction with sufficient accuracy. A line sensor receives light emitted from a light source and reflected by an original. When a pressure plate that presses an original to a platen is closed, a control unit controls to supply a line periodic signal of which a period is longer than that for reading an original image to the line sensor, and to supply a lighting control signal of which a duty ratio is smaller than that for reading the original image to the light source in synchronization with the line periodic signal to light the light source and to read an image, and controls to detect length of the original in the principal scanning direction using the image signals from the line sensor.

A control unit causes a carriage to move in a width direction under a first movement control of changing a location of the carriage with a first resolution so that a sensor located forward in movement detects an edge of a medium. Thereafter, the first movement control is switched to a second movement control of changing the location of the carriage with a second resolution higher than the first resolution and the carriage is caused to move in the width direction so that a sensor located rearward in movement detects the edge.

An image reading apparatus comprises a platen, a support, a reader, an open/close unit, a first obtainer, a mark, a positioning member, and a determiner. A position of the mark on a pressing surface of the cover, is provided at a position at which, in a case where a sheet of a maximum size among standard sizes that can entirely fit in a readable range of the reader is positioned with respect to the positioning member, at least a portion of the mark is not hidden by the sheet as viewed from the reader.

An image forming system includes an image former, a first reader, and a second reader. The image former forms an image on a recording medium. The first reader is provided upstream of an image former 300 in a conveyance direction of the recording medium, and reads the recording medium. The second reader is provided downstream of the image former 300 in the conveyance direction of a recording medium S and reads the recording medium S. The first reader and the second reader control each other based on the respective reading results.

An image reading apparatus is provided with a reader which reads a document, a transport roller which is provided on an upstream side of the reader in a document transport path in which the document is transported and transports the document to a reading position of the reader, and a controller which receives reading data of the reader and controls the transport roller, in which the controller receives the reading data from the reader to acquire a form of the document, and selects whether or not to stop driving of the transport roller based on the form.

An image forming apparatus which can control to turn on/off a light emitting element depending on a sheet state on a manual sheet tray is provided. The image forming apparatus includes the manual feed tray on which the sheet is placed. The image forming apparatus is configured to be switchable between normal power mode and power saving mode. In the normal power mode, normal power is supplied. In the power saving mode, less power is consumed as compared to the power consumed in the normal power mode. The image forming apparatus includes a manual sheet feeding sensor which detects presence/absence of the sheet on the manual feed tray. The image forming apparatus includes a sheet length sensor S and a sheet length sensor L which include the light emitting element and a light receiving element to detect approximate sheet length of sheet placed on the manual feed tray in a conveying direction.

An image reading apparatus includes: a first size-detecting portion which detects a size of an original disposed on a disposing portion; a conveying portion which conveys the original disposed on the disposing portion to a reading portion, a second size-detecting portion which detects the size of the original to be conveyed by the conveying portion; a controller which calculates an overlap region between a reading region and an original region, with the reading region determined based on a reading size obtained by a obtain portion and the detection of the first size-detecting portion, and the original region determined by the second size-detecting portion; and a notifying portion which makes a predetermined notification based on the information that has been calculated.

A controller of an image reading apparatus is configured to cause the reading device to read an image on an original with moving a reading location from a first position to a second position, after reading the image on the original with moving the reading location from a third position to the first position, the third position being a position between the first position and the second position and spaced from the first position by a particular distance and determining a width of the original in the main scanning direction. The controller is configured to further move the reading location from the second position to the first position, and detect an instruction to continue reading a subsequent original during a period before the reading location reaches the third position. When the instruction is detected, the controller stops moving the reading location when it reaches the third position.

An image reading device includes an accommodation section, an aligning member, a reading member, and a width detector. The accommodation section accommodates at least one document. The aligning member is provided in the accommodation section, is supported in a movable manner in a width direction intersecting a transport direction of the document, and aligns a widthwise edge of the document. The reading member reads an image of the document passing through a read position preset in a transport path. The width detector detects a width of the document based on a widthwise position of the aligning member if the document is of a typical size, and detects the width of the document based on the image read by the reading member if the document is of an atypical size.

An image forming apparatus includes: an edge detection unit that detects one edge, in a conveyance direction, of a conveyed sheet; a passing detection unit that detects passing of the one edge; a judging unit that judges whether the edge detection unit or the passing detection unit has detected the one edge, within a predetermined monitoring time after the edge detection unit or the passing detection unit detected the one edge; a notifying unit that gives a notification indicating that front-back magnification correction is difficult to perform on the sheet when the judging unit has judged that the one edge is not detected within the monitoring time; an acquiring unit that acquires a desirable front-back magnification correction value input via an input unit according to the notification; and a correction unit that performs a front-back magnification correction process on the sheet, using the acquired front-back magnification correction value.