Method and microscope for high spatial resolution examination of samples

A laser scanning fluorescence microscope for carrying out a method of high spatial resolution examination of a sample, the sample to be examined comprising a substance that can be repeatedly converted from a first state into a second state, the first and the second states differing from one another in at least one optical property, comprising:

• a microscope objective for imaging an optical signal onto a focal plane in the sample, and for receiving a measuring signal emanating from the sample;
• an optical component for producing a pupil line in a pupil plane conjugate with a pupil of the microscope objective;
• and
• a phase modulating element for producing a cross-sectional profile of a focal line by phase modulation of the pupil line, wherein the optical signal is provided in the form of the focal line with a cross-sectional profile having at least one intensity zero point with laterally neighboring intensity maxima,
• wherein the phase modulating element is designed as a spatial liquid-based phase modulator arranged in an intermediate image of the pupil, or as an optical component having a phase retarding dielectric coating arranged in the intermediate image of the pupil.