Patent ID: 8174761

Claim:
A total internal reflection microscope for epi-fluorescence illumination observations, said microscope comprising an objective, through which an object to be observed is illuminated by an excitation illumination light at an angle with respect to an observation axis of said microscope, said angle being adjustable to be within a range suitable for a total internal reflection observation; a source of collimated excitation light; an interferometer, arranged in an optical path of the collimated excitation light, said interferometer being configured to produce an interference pattern; a focusing lens system comprising at least one focusing lens, said focusing lens system being configured to focus the interference pattern produced by the interferometer into a back focal plane of the objective; wherein the objective and the focusing lens system are configured and arranged to produce excitation illumination light which is spatially modulated in its intensity in a plane orthogonal to the observation axis of said microscope.