Image reading apparatus and image reading system

An image reading apparatus configured to read an image on a sheet-like medium conveyed on a conveyance path by an automatic conveying device, the image reading apparatus comprising:

• a light source arranged opposite to one surface of the medium;
• a background member arranged opposite to another surface of the medium, the background member including a background surface that faces the another surface of the medium;
• an imaging unit arranged opposite to the one surface of the medium and at a position different from the light source in a conveyance direction of the medium, and configured to pick up an image of the medium and the background surface on which a shadow of the medium is formed due to light from the light source;
• and
• an image processor configured to generate image data including the image of the medium and the background surface based on an image pick-up result by the imaging unit, wherein
• the background surface is inclined with respect to the conveyance path such that a gap between the conveyance path and the background surface decreases from a light source side toward an imaging unit side in the conveyance direction.