The microscope (S, 100) of the present invention has a hand piece (20, 112), whose tip is mounted with a thin sheet-like mirror unit (M, 10, 130, 220), and around both ends of the base (11c, 131c) thereof is arranged an illuminating light source (32, 117), whereby light is emitted to a target object, image light is lead through the light reception bore (27, 116), to the optical system (114), and is recorded at the CCD camera (111), to obtain video images. The thin sheet-like mirror (M, 11, 131) confines light and navigate it, wherein the width of the mirror can be made narrower like a convergent taper surface (11a, 131a); and it is comprised of a base surface (11c, 131c) where illuminating light comes in and image light goes out, and a mirror surface (11b, 131b) where illuminating light and image light go back and forth, and make the reflection thereof, and the mirror surface (11b, 131b) is slanted to 45 degrees. The microscope may be used as a handy microscope if it is not equipped with a charge-coupled device camera. The microscope can provide a wider horizon, which makes it possible to make a horizontal observation in an extremely narrow space, and can be manufactured at a less expensive price.