Beijing Key Laboratory for Precision Optoelectronic Measurement Instrument and Technology, School of Optics and Photonics, Beijing Institute of Technology, Beijing 100081, China
Considering the urgent demand for the characterization of chemical composition in the micro-zone of samples with complex morphology, we developed a confocal laser-induced breakdown spectroscopy (LIBS) microscope in this study. First, the microscope used the continuous laser reflected from a sample to construct a laser confocal system with high spatial resolution, ensuring accurate focusing and three-dimensional (3D) morphological measurement of the sample. Then, the LIBS signals were excited by common-path pulsed laser to achieve full-elemental detection of the sample, thereby realizing 3D elemental imaging with high spatial resolution and anti-drift properties. The experimental results show that the lateral resolution of multi-elemental maps can reach 10 μm, and the combined uncertainty of the system's spectral detection is 2.24%. Furthermore, 3D elemental maps were constructed after combining with the in-situ morphological information and LIBS information in the system. In conclusion, the system provides new perspectives for the chemical analysis of samples with complex morphology such as biological tissue and micro-nano materials.