An image reading device which is capable of enhancing productivity in reading bound originals, such as a book, a magazine, or a document. A sheet-scanner device implementing the image reading device includes a sheet scanner as a reader part for reading an image on an original. The sheet scanner comprises a sheet-like substrate formed thereon with a light-emitting layer that can emit light spontaneously, and a light-receiving layer on which a plurality of reading pixels are arranged. The sheet scanner is mounted in the sheet-scanner device such that the sheet scanner can be drawn out onto and in from the original.