Patent ID: 8848209

Claim:
An image sensor unit comprising: a light source that illuminates an object to be read; a sensor substrate unit that is connected with a plurality of sensor substrates comprising a plurality of photoelectric conversion elements arranged and mounted in a line in a longitudinal direction that is a main-scan direction; a light condenser that focuses light from the object to be read on the sensor substrate unit; and a supporting body that supports the light source, the sensor substrate unit, and the light condenser, wherein the sensor substrate unit is formed by connecting edges of the sensor substrates in the longitudinal direction, at the edges of the sensor substrates, a convex portion is formed that protrudes in the longitudinal direction of the sensor substrates from positions on base ends not to overlap the photoelectric conversion elements in plan view, farthest tips of the photoelectric conversion elements are positioned outside of the base ends in the longitudinal direction of the sensor substrates, and inside of farthest edges of the convex portions in the longitudinal direction of the sensor substrates, and the sensor substrates to be connected are connected to each other so that a distance of a gap in the main-scan direction formed between the farthest tips of the photoelectric conversion elements is smaller than a distance of a gap in the main-scan direction formed between the farthest edge of the convex portion of one of the sensor substrates and the base end of the other of the sensor substrates.