Fig. 1. Principle diagram of inversion algorithm for thin oil film

Fig. 2. The relationship between measurement error and R

Fig. 3. The relationship between k_e+k and maximum inversion thickness with different errors

Fig. 4. Experimental equipment structure

Fig. 5. Experimental results
(a): Background fluorescence and Raman scattering light spectra of sea water; (b): Feature fluorescence spectrum of oil; (c): Fluorescence spectra of 200 μm oil film measured 30 times; (d): Fluorescence spectra of oil films with different thickness

Fig. 6. k_e+k value of experimental oil

Fig. 7. Estimate results of oil films with different thickness