CPC Class H04N

An image forming apparatus includes an image forming portion, a casing, an image reading portion, a first controller substrate provided on one of side surfaces of the casing, a second controller substrate provided on the side surface, wherein a component mounting surface of the second controller substrate is in a non-overlapping position with a component mounting surface of the first controller substrate, an electric wire configured to connect the first controller portion and the image reading portion, and a shielding member fixed to the casing so as to be provided between the electric wire and the second controller substrate and configured to shield electromagnetic radiation from the second controller substrate toward the electric wire.

An automatic document feeder, which is included in an image reading device and an image forming apparatus, includes first and second document trays, a document output tray, a document conveying passage, multiple document conveying bodies, a drive source, a detector, and a controller. The multiple document conveying bodies include a document holding and conveying body to convey and hold the original document sheet on the second document tray. On detection of the original document sheet on the second document tray while conveying a different original document sheet from the first document tray, the controller stops feeding the different original document sheet, causes the different original document sheet downstream from the document holding and conveying body in a document conveying direction to be conveyed to the document output tray, and stops the drive source after the different original document has been conveyed to the document output tray.