Patent ID: 8867108

Claim:
An illumination device which illuminates a manuscript surface, comprising: a light source unit having a plurality of LED light sources arranged in a predetermined direction; an optical member having a plurality of reflecting surfaces, which collects light from the light source unit; and a reflecting member having a plurality of reflecting surfaces, which reflects the light from the optical member toward the manuscript surface; wherein at least one surface of the plurality of reflecting surfaces of the optical member and the plurality of reflecting surfaces of the reflecting member reflects light vertically emitted from a light receiving surface of the LED light sources, and wherein the at least one surface includes a reflection surface having a relief structure which changes a traveling direction of incident light in an arrangement direction of the plurality of LED light sources; wherein the optical member includes two reflecting surfaces facing each other, and the facing reflecting surfaces are disposed such that a distance on an emission side is longer than a distance on an incident side; wherein each of the facing reflecting surfaces includes one plane; wherein the illumination optical system includes a plurality of reflecting members, and each of the plurality of reflecting members reflects the light from the optical member to illuminate a reading target area; and wherein an arrangement space of the plurality of reflecting members is divided, by a plane through which light reflected from the reading target area and used for an image formation passes, into two divisions; a first region and a second region, and at least one reflecting member of the plurality of reflecting members is disposed in the first region, and at least one reflecting member of the plurality of reflecting members is disposed in the second region.