The document read apparatus according to the present invention has a light
source unit that includes a linear first light and second light sources,
both light sources aligned parallel to the sub scanning direction (moving
direction). When the light source unit is scanning a book document in a
second region shifted toward a side of the first light source from a
center position for emitting light to the center of the document, a light
quantity of the second light source becomes larger than a light quantity
of the first light source. When the light source unit is scanning the
book document in a third region shifted toward a side of the second light
source from the center position, the light quantity of the first light
source becomes larger than the light quantity of the second light source.
A sum of both light quantities is controlled to be constant.