Development of a large depth of field collection optics for on-line Laser-Induced Breakdown Spectroscopy applications

This paper deals with the study of the collection optics required by a LIBS system that has to perform on-line analysis of moving samples whose distance may vary during measurements. Main requirement of this system is to maintain good collection efficiency over a wide range of sample distances by using a fixed focus optical arrangement. The selected configuration is based on the use of two spherical mirrors with the same curvature radius. Tests carried out on an experimental prototype are in good agreement with the previously performed simulations.