An image reading device including: a motor to reciprocate a carriage, a reference position detector to detect passage and non-passage of the carriage through a reference position and output a detection result, and circuitry configured to, in a case where an abnormality of a stop position of the carriage has been detected based on the detection result, specify a location at which the carriage has abnormally stopped.

Reference portions are arranged in a reference area outside a main area in a main scanning direction, each having a lower surface of one of a plurality of determination colors. A reference data offset value is set based on reference pixel data of the reference area obtained when a light emitting unit of a scanning unit is not caused to emit light. A color determination process is executed to correct the reference pixel data in line image data obtained when the light emitting portion is caused to emit light with the reference data offset value, and to determine which determination color the corrected reference pixel data is data of. A unit drive device executes driving operations that are sequentially selected from a plurality of trial driving operations according to the determination result of the color determination process, and positions the scanning unit at a home position.

A method for determining fiducial markers to be printed on a substrate by means of a printer which is configured to execute a print process and to transport the substrate relatively to a gantry comprising a print head and an image scanner in a main scanning direction over a print surface underneath the gantry. The print head and the image scanner are moveable along the gantry in a sub-scanning direction perpendicular to the main scanning direction. The printhead is configured to eject marking material on the substrate and the image scanner is configured to create scanned images of the printed substrate. Based on properties of the scanned images of prepared patches on the substrate a color and a shape of the fiducial markers to be printed is selected and stored per type of substrate.

An image reading device includes a document table, an image reading unit, a reading unit moving part, a cursor, and a cursor moving part. The reading unit is disposed below the document table, and scans the placed document in a main-scanning direction to read an image. The reading unit moving part moves the reading unit in a sub-scanning direction crossing the main-scanning direction and in an opposite direction. To the cursor, a reading start side edge of the document placed on the document table in the sub-scanning direction is abutted. The cursor moving part moves the cursor along the sub-scanning direction in a reciprocating manner. The cursor moving part moves the cursor from a reference position of the reading unit in the opposite direction in conjunction with a movement of the reading unit from the home position in the opposite direction.

A medium conveying apparatus includes a conveyance roller to convey a medium, a DC motor to drive the conveyance roller, a processor to rotate the DC motor, an encoder to output a first pulse signal whose cycle varies according to a rotation speed of the DC motor, and an imaging device to acquire an image acquired by imaging a conveyed medium in response to a pulse of a second pulse signal whose cycle is constant. The processor detects a number of pulses of the second pulse signal included in a predetermined cycle of the first pulse signal, and discards images acquired by the imaging device in the same number of pulses as difference between the detected number of pulses and a reference number, in a next cycle of the predetermined cycle of the first pulse signal, when the detected number of pulses exceeds the reference number.