径向偏振光瞳滤波共焦拉曼光谱显微系统研制

To improve the spatial resolution of confocal Raman system, a radial-polarized pupil-filter confocal Raman microscope system (RPCRS) is developed. The radial polarized light generator (S-plate) is used to convert the linearly polarized light from the laser into radially polarized light. Then, a pupil filter is utilized to modulate the radially polarized light to realize the compression of the Raman excited spot. Finally, the spatial resolution of confocal Raman microscope system is improved by a pinhole to eliminate the Raman scattering light outside the focus. This system has high spatial resolution and lateral sensitivity. The periodic scribes and the standard steps are used as samples. Experimental results show that the spatial resolution of RPCRS can reach 240 nm, the lateral sensitivity is 46.5% higher than that of common confocal Raman microscope system, and the uncertainty of transverse measurement standard is 18.87 nm. This system can realize high spatial resolution imaging of confocal Raman microscope system.