1. An optical system for enlarging a field of view with respect to an object by high-speed scanning, image capture, and image mosaicking along an optical path, comprising: an objective lens or lens assembly positioned downstream from the object along the optical path so that the object is positioned at a focal plane of the objective lens or lens assembly; an iris downstream from the objective lens or lens assembly along the optical path; one or more scanning mirrors placed downstream from the iris along the optical path for optical high-speed scanning; one or more imaging lenses downstream of the scanning mirrors along the optical path; a high-speed digital imaging device downstream of the imaging lenses along the optical path; and means for processing and constructing scanned and captured images into a mosaic image.