A scanner that combines images read by a first sensor array (21a1) and a second sensor array (21a2), wherein the first sensor array and the second sensor array have read regions which partially overlap, and the scanner comprises: a combining section that combines a first read image read by the first sensor array and a second read image read by the second sensor array and calculates a degree of relative deviation between the first read image and the second read image in a main scanning direction (Y) in a region read by both the first sensor array and the second sensor array in an overlapping manner; an acquisition section that acquires the degree of relative deviation calculated by the combining section ; and a correction section that corrects, based on the degree of relative deviation, an image after a combining process is performed by the combining section; wherein the correction section is configured to correct the image based on the degree of relative deviation acquired by the acquisition section ; characterised in that the correction section is configured to correct the image such that the correction amount of the sharpness of the image is increased as the degree of relative deviation increases; and the correction section determines a correction target region based on a distribution of the degree of relative deviation. wherein the first sensor array and the second sensor array have read regions which partially overlap, and the scanner comprises: a combining section that combines a first read image read by the first sensor array and a second read image read by the second sensor array and calculates a degree of relative deviation between the first read image and the second read image in a main scanning direction (Y) in a region read by both the first sensor array and the second sensor array in an overlapping manner; an acquisition section that acquires the degree of relative deviation calculated by the combining section ; and a correction section that corrects, based on the degree of relative deviation, an image after a combining process is performed by the combining section; a combining section that combines a first read image read by the first sensor array and a second read image read by the second sensor array and calculates a degree of relative deviation between the first read image and the second read image in a main scanning direction (Y) in a region read by both the first sensor array and the second sensor array in an overlapping manner; an acquisition section that acquires the degree of relative deviation calculated by the combining section ; and a correction section that corrects, based on the degree of relative deviation, an image after a combining process is performed by the combining section; wherein the correction section is configured to correct the image based on the degree of relative deviation acquired by the acquisition section ; characterised in that the correction section is configured to correct the image such that the correction amount of the sharpness of the image is increased as the degree of relative deviation increases; and the correction section determines a correction target region based on a distribution of the degree of relative deviation. <EOS>