Microscope apparatus with fluorescence cube for total-internal-reflection fluorescence microscopy

A microscope apparatus comprising:

• an illumination optical system that illuminates a sample with laser light from a laser light source;
• a fluorescence detection optical system that detects fluorescence from the sample;
• a plurality of fluorescence cubes that are interchangeably provided in an optical path of the illumination optical system, at least one of the plurality of fluorescence cubes including a dichroic member therein which directs the laser light to the sample;
• and
• an objective lens;
• said at least one of the plurality of fluorescence cubes further including an optical member that makes a principal ray of the laser light substantially parallel to an optical axis of the illumination optical system and concentrates the laser light on a given position that is on a pupil position of the objective lens and separated from the optical axis,
• the optical member including a wedge prism and an imaging lens, in order, along a direction from an incident side of the at least one of the plurality of fluorescence cubes to the dichroic member therein,
• wherein the optical member is constructed such that, when said at least one of the plurality of fluorescence cubes is inserted into the optical path of the illumination optical system, laser light whose principal ray is tilted by a given angle with respect to the optical axis of the illumination optical system is incident on the wedge prism and exits from the wedge prism substantially parallel to the optical axis of the illumination optical system.