Patent ID: 9350893
Filing Date: 2016-05-24
CPC Classification: H04N

Claim Text:
1. An overhead image reading apparatus comprising: an optical unit arranged to be rotatable around a rotation axis extending horizontally in a main scanning direction, the optical unit including: a drive unit including a drive source to control a rotation angle of the optical unit; an interface configured to receive an instruction to start reading; and a brightness controller to control the light source, the image-capturing unit and the drive unit, the brightness controller configured to the brightness controller controls the light source and the drive unit so that the brightness controller controls the light source to gradually increase the brightness of the light source from zero to the predetermined brightness while controlling the drive unit to rotate the optical unit from a storage position at which the optical unit is stored inside a cover toward a furthest reading position at which the optical unit reads an image at a backmost area in a readable range, after receiving the instruction to start reading, the brightness controller controls the light source to gradually decrease the brightness of the light source from the predetermined brightness to zero at a nearest reading position at which the optical unit reads an image at a nearest area in the readable range, or while controlling the drive unit to perform an operation of storing the optical unit, after reading of medium is completed, and the brightness controller controls change rates of brightness of the light source according to ambient light so that the change rate of brightness of the light source when the ambient light is bright, becomes greater than the change rate of brightness of the light source when the ambient light is dark.