To provide an image reading apparatus which can read images, without affecting data read from the image.

The apparatus for reading the image delays starting of a "Process time" by deviating back the starting position P1 of the data transfer of the Process time so that timing of B1 becomes after initial switching timing SHT1 of a shutter, in such a manner that the image data transfer "Area" is not superposed with the initial switching timing SHT1, when the initial switching timing SHT1 of the shutter is superposed with the image data transfer Area of the Process time. If an SHT2 is superposed with the Area, after the starting position P is shifted to the back, the timing of the Process is shifted so that the Area is not superposed with the SHT2. When the ending position P2 of the data transfer of the Process time is disposed farther rearward from the reading finishing end L2 of 1 Line, the reading time per 1 Line is extended by the length 81 of the part of the finishing end B2 of the image area of the transfer ending point of the image data, from the starting position P1 of the data transfer of the Process time.