US Patent 7538912 Image reading apparatus and circuit board unit used therefor

An image reading apparatus (X) includes a light source, a case (2) for accommodating the light source, and a substrate (8) mounted to the case (8). A plurality of sensor IC chips (7) for detecting the light traveling from an image reading region are mounted on the substrate (8). The sensor IC chips (7) are arranged at positions closer to a second side edge (8b) than to a first side edge (8a) of the substrate. A predetermined wiring pattern is formed on the substrate (8). The sensor IC chips (7) are electrically connected to the wiring pattern via wires (W). The wires (W) are connected to the wiring pattern by extending from the upper surface of the sensor IC chips (7) toward the first side edge (8a) of the substrate.