IMAGE SCANNER

PROBLEM TO BE SOLVED: To provide an image scanner which scans the images of large originals at high resolution, without increasing the number of pixels of a linear sensor. SOLUTION: The image scanner is provided with two first mirrors 31a and 31b, fixed so that the first mirrors are symmetric with respect to an imaginary plane S, which includes an axis in the direction of sub-scan and is perpendicular to main scanning line, at such a position that the axes in the longitudinal direction of the reflection surfaces 50a and 50b of the first mirrors 31a and 31b are not parallel with the main scanning line. The image scanner is further provided with a movable second mirror 33, so that the axis in the longitudinal direction of the reflective surface 52 of the second mirror 33 is parallel with the axes in the longitudinal direction of the reflection surfaces 50a and 50b of the first mirrors 31a and 31b, and the second mirror is located in first position and second position, which are symmetrical with respect to the imaginary plane S. Further, a lens 30, which forms part of the image of an original on the main scanning line on the linear sensor 20, is placed in the optical path connecting the second mirror 33 and the linear sensor 20. The images of the original in adjoining areas on the main scanning line are superposed and formed on the linear sensor 20 by driving the second mirror 33.