Patent ID: 8586945

Claim:
A fluorescence light scanning microscope, comprising a light source providing a beam of excitation light of an excitation wavelength for exciting a fluorophore in a sample to be imaged for spontaneous emission of fluorescence light, and providing a beam of suppression light of a suppression wavelength for suppressing spontaneous emission of fluorescence light by the fluorophore on a common optical axis of the beams of excitation light and suppression light, the suppression wavelength differing from the excitation wavelength; an objective focusing both the beam of excitation light and the beam of suppression light into a focus volume around a focus point; a detector adapted to detect fluorescence light spontaneously emitted by the fluorophore; and a chromatic beam shaping device arranged on the common optical axis of the beams of excitation light and suppression light, and including a chromatic optical element adapted to shape the beam of suppression light such as to produce an intensity distribution of the suppression light around the focus point having an intensity zero essentially at the focus point, and to leave a shape of the excitation light such as to produce an intensity distribution of the excitation light around the focus point having a maximum essentially at the focus point, wherein the chromatic optical element includes a birefringent chromatic optical element adapted to shape a polarization distribution of the beam of suppression light over its beam cross section.