Remote multicolour excitation laser-induced fluorescence imaging studies

This research introduces an advanced remote multicolour excitation laser-induced fluorescence (LIF) imaging technique, utilizing a mobile lidar system equipped with a frequency-tripled Nd:YAG laser and optical parametric oscillator. Operating across UV to near-infrared wavelengths, this method significantly enhances non-destructive material surface analysis. The system's efficacy is validated in varied settings, including laboratories and outdoor environments like stadiums and cultural heritage sites, effectively distinguishing material properties at distances up to 60 meters. The study emphasizes the integration of multiple excitation wavelengths to capture diverse fluorescence characteristics, improving material heterogeneity detection. Utilizing correlation analysis, the method compares fluorescence spectra against reference spectra to ascertain material composition with high precision. Key to this research is the LIF system's ability to differentiate materials without physical contact, exemplified by the analysis of antique bricks. This capability, along with the system's stability in spectral data acquisition, synthesis of composite spectra from varied wavelengths, and efficient data processing, positions this technology as a potent tool in cultural heritage preservation and a precursor to future advancements in remote sensing and diagnostic imaging.