Patent ID: 7760403

Claim:
An optical irradiation apparatus, comprising: a light source including an exit side configured to radially irradiate light, said light source including an arrangement of a plurality of light emitting units in at least one sequence; a light source array board with a side intersecting with the exit side of the light source; and a light guide including a transparent material configured to lead a light beam irradiated from the light source in a specific direction and to emit the light beam, the light guide including an incidence surface configured to receive the light beam irradiated from the light source, said incidence surface facing the exit side of the light source, an exit surface configured to emit the light beam so as to irradiate a manuscript on a contact glass, and plural connecting surfaces configured to connect the incidence surface to the exit surface, wherein a part of at least one of the plural connecting surfaces is inclined with respect to an axis of the light beam and at least a portion of a connecting surface facing the inclined connecting surface is on the light source array board.