Patent attributes
An image reader includes an image sensor including a plurality of light receiving elements. The plurality of light receiving elements receive a reflection light from a document and perform photoelectric conversion. The image reader further includes an MTF calculation portion which calculates an MTF of the image sensor based on image data which is obtained by reading a predetermined MTF detection pattern. Moreover, the image reader includes an image processing portion which divides the plurality of light receiving elements into a first MTF region and a second MTF region. The image processing portion performs a first image process on the plurality of image signals which are outputted from the light receiving elements in the first MTF region and a second image process on the plurality of image signals which are outputted from the light receiving elements in the second MTF region.