The feeder roller 21 may work in conjunction with the separator pad 22 to feed a plurality of original sheets GS serially one by one to the image reader 24. The feeder roller 21, the upstream conveyer rollers 23, and the downstream conveyer rollers 26 are driven by a conveyer motor MT (see FIG. 4). The platen glass 25 is light-transmissible and is disposed at a lower position with respect to the conveyer path 20 along the conveyer path 20. The upstream and downstream conveyer rollers 23, 26 are disposed at a central position in the main-scanning direction MD in the conveyer path 20 and may convey the original sheets GS fed by the feeder roller 21 over the platen glass 25 at a predetermined interval.

The original sheets GS may be placed on the feeder tray 2 in such an arrangement that an object surface of the original sheet GS to be read may face the supporting surface of the feeder tray 2. The image reader 24 is disposed at a lower position with respect to the conveyer path 20 and may read an image on the object surface of the original sheet GS as the original sheet GS is conveyed over the platen glass 25. In the feeder tray 2, disposed is a sheet sensor 27, which may be switched on when the feeder tray 2 supports the original sheets GS and switched off when no original sheet GS is placed on the feeder tray 2.

<Detailed Configuration of Image Reader 24>