Image processing apparatus

An image processing apparatus switchable between an observation mode for projecting an image onto an observation position and a read mode for projecting the image onto a read position includes an optical system for forming an optical path for projecting the image onto the observation position. The optical system includes at least one movable mirror for receiving a light beam from the image. The mirror is movable to a first position for reflecting the light beam from the image toward the observation position and to a second position for reflecting the light beam toward the read position. The apparatus also includes a first moving mechanism for moving the mirror to the first position and to the second position, an image sensor disposed at the read position and movable so as to enter into the optical path or to retreat from the optical path, and a second moving mechanism for moving the image sensor along a straight line crossing the optical path.