Coherent anti-Stokes Raman scattering microscopic method and system of super-diffraction limit

Abstract

The invention is applicable to the field of laser detection and provides a coherent anti-Stokes Raman scattering microscopic method and system of a super-diffraction limit. In the method, a spatial resolution of the super-diffraction limit can be obtained through increasing an additional detecting light which is collinearly focused on a sample together with a pump light and a Stokes light at the same time, enabling the additional detecting light to exhaust phonons generated by the pump light and the Stokes light on a periphery of a focal spot so as to form useless CARS (Coherent Anti-Stokes Raman Scattering) signals, enabling photons in accordance with a phase matching condition in the delayed detecting light to hit phonons at a central area of the focal spot so as to form useful CARS signals, and separating the useless CARS signals. Because supercontinuum laser with a broad band is adopted as the pump light and the Stokes light, a complete CARS spectrum signal of a molecule is obtained to image the whole molecule.

Description

technical field [0001] The invention belongs to the field of laser detection, in particular to a super-diffraction limit coherent anti-Stokes Raman scattering microscopic method and system. Background technique [0002] The spatial resolution of an optical microscope is limited by the diffraction limit, which is ultimately determined by the wavelength of the light wave and the numerical aperture of the microscope. If δ is used to represent its limit resolution, λ represents the wavelength of light, and NA represents the numerical aperture of the optical system, then δ=0.61λ / NA. Generally, δ≥200nm. [0003] In recent years, the diffraction-limited resolution of fluorescence microscopy has achieved a major breakthrough thanks to special measures. Two different measures are mainly taken, one is based on the single-point scanning imaging method, using the stimulated emission depletion (STED) method, using the ring light to make the surrounding area of ​​the point spread functi...

AI Technical Summary

Problems solved by technology

At present, the research on CARS nano-resolution microscopic imaging technology is still in the stage of theoretical demonstration in the world. At the same time, it can also be seen that even if the above-mentioned scheme can achieve nano-resolution, it is limited to imaging a single chemical bond of a molecule.

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