観察装置

An observation device (100) that comprises an illumination optical system (3) and an imaging optical system (4) that are arranged below a stage (2). The illumination optical system (3) comprises: a light source (5); an illumination mask (7) that restricts illumination light from the light source (5) to a first emission region (7a); a collimation lens (8) that converts illumination light from the first emission region (7a) into substantially collimated light; and an emission region restriction member (9) that restricts illumination light from the collimation lens (8) to a second emission region (9a). An image of the first emission region (7a) as projected onto a pupil surface of the imaging optical system (4) partially overlaps an edge portion of a pupil (11a) and satisfies the following conditional expressions. 0.1NA