Abstract：Micro-area confocal Raman spectroscopy reflects the structural characteristics of substances and can be used to analyze the chemical components of organic or inorganic samples. In this paper, a micro-area Raman optical system based on differential confocal microscopy (DCM) is developed to detect the micro-area Raman spectroscopy of inorganic samples. The traditional confocal Raman spectroscopy technology does not emphasize the focusing ability of the system. The optical system device uses the characteristics of the zero-crossing point of the differential confocal curve and the precise correspondence of the focal point position, uses the feedback control technology to realize the long-time focusing function. Laser incidence and Raman signal collection in micro-area are realized by multi-mode optical fiber spatial coupling technology. The experimental results show that the device has high stability and can effectively detect the micro-area Raman spectra of single-walled carbon nanotubes and pure sulfur and realize the single-line detection of the carbon tube. The device meets the design requirements of the spectral detection system. It provides experimental data reference for the development of micro-area confocal Raman optical system with higher performance and the optimization of optical path design.
2020, Vol. 41 
