A method for simultaneous two-dimensional visualization of water in both gas and liquid phase is presented. This laser-based diagnostic technique uses a combination of two-photon laser-induced fluorescence (LIF) and spontaneous Raman scattering. A tunable KrF excimer laser, operating near 248 nm, was used as an excitation source. The technique was demonstrated on single water droplets and their surrounding gas-phase content. Prior to the visualization experiments, spectroscopic measurements were performed to find optimum filtering conditions.
Michel Versluis, Greger Juhlin, Oivind Andersson, and Marcus Alden, "Two-Dimensional Two-Phase Water Detection Using a Tunable Excimer Laser," Appl. Spectrosc. 52, 343-347 (1998)