Patent ID: 7495682

Claim:
An image reading apparatus, comprising: a plurality of point light sources, arranged in a straight line state, configured to output light to light a document; a light leading member, positioned in front in a light outputting direction of the light output from the point light sources, configured to receive the light incident on a surface of the light leading member, and to lead the received light so as to irradiate along a main scanning direction toward the document; a photoelectric conversion element configured to receive reflection light from the document; a point light source array substrate where the point light sources are provided in the line state; and a holding part having a mounting surface extending in parallel with the longitudinal direction of the light leading member, the mounting surface being where the point light source array substrate is mounted, wherein the light leading member includes a positioning unit configured to make a gap between one of the point light sources arranged in the line state and the light leading member the same as a gap between another of the point light sources and the light leading member, and to make an arrangement direction of the point light sources be positioned along a longitudinal direction of the light leading member.