Super-resolution microscopic imaging method and apparatus based on common-path parallel fluorescence emission difference microscopy

A super-resolution microscopic imaging method based on common-path parallel fluorescence emission difference microscopy, comprising:

• step (1), collimating a laser beam emitted by a laser, and converting the laser beam into linearly polarized light by a polarizer, wherein the linearly polarized light contains an S component and a P component;
• step (2), adjusting an exit plane of a liquid crystal spatial light modulator to conjugate with an entrance pupil of a microscopic objective lens;
• modulating a polarization component of the linearly polarized light in the step (1) parallel to a modulator polarization direction using half of the liquid crystal spatial light modulator by 0-2π vortex phase modulation, but not modulating a polarization component perpendicular to an adjusted polarization direction;
• step (3), emergent light of the liquid crystal spatial light modulator reaching a reflector after passing through a quarter-wave plate, being reflected back to the quarter-wave plate by the reflector, and reaching the other half of the liquid crystal spatial light modulator;
• step (4), loading the other half of the liquid crystal spatial light modulator as a blazed grating, in such a manner that an unmodulated component of the linearly polarized light is modulated to be inclined, and calculating an inclination angle by adjusting a grating constant according to a grating equation, in such a manner that solid spot and doughnut-shaped spot are staggered on an object plane;
• step (5), converting two paths of light emitted from the other half of the liquid crystal spatial light modulator into circularly polarized light;
• step (6), two paths of the circularly polarized light presenting staggered solid spot and doughnut-shaped spot on a sample plane, the solid spot and the doughnut-shaped spot scanning a sample at the same time, and exciting two paths of fluorescence signals to pass through respective detection light paths, respectively, and to be received by two detectors, and obtaining confocal light intensity distribution and negative confocal light intensity distribution;
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• step (7), shifting the negative confocal light intensity distribution to correspond to the confocal light intensity distribution, and obtaining a super-resolution image according to a fluorescence emission difference microscopy formula.