A movable objective lens assembly that includes an infinity-corrected objective lens providing the microscope with an optical field of view. The assembly permits the imaging of a specimen under investigation over an area of the specimen much larger than the field of view of the objective lens without moving the microscope and/or a specimen stage relative to one another. The assembly includes a mirror system and the linearly movable infinity-corrected objective lens. The mirror system includes a plurality of mirrors that provide a folded optical path that allows the objective lens to be moved relative to the specimen without moving the entire microscope. The mirror system and the objective lens are pivotably mounted relative to the rest of the microscope so as to allow the objective lens to be located substantially anywhere within a circular, or circular-sectoral, viewing area.