To easily perform the changeover use and combination use of a coaxial illumination method and a 6° illumination method.

This microscope is provided with an observing optical system 2 for observing an eye to be tested, a light beam guiding optical system 3 introducing almost all of the illuminating light beam from an illuminating optical system 1 to the eye to be tested E1 along the optical axis of the observing optical system, a total reflection prism introducing almost all of the illuminating light beam of the illuminating optical system to the eye E1 from an angle different from that of the illuminating light beam introduced by the light beam guiding optical system and a half prism P2 introducing a part of the illuminating light beam of the illuminating optical system to the light beam guiding optical system by transmitting it through the prism and introducing the remaining illuminating beam to the eye E1 from an angle different from that of the illuminating light beam introduced by the light beam guiding optical system. This microscope has a moving substrate 4 mounting the total reflection prism and the half prism in a prescribed direction and is provided with a moving means for locating either the total reflection prism or the half prism between the illuminating optical system and the light beam guiding optical system by moving the moving substrate in a prescribed direction.