Fig. 1. Interferometric optical path diagram for real-time measurement of liquid refractive index

Fig. 2. Optical path diagram of split-tip equal-thickness interferometry

Fig. 3. Spectral analysis results of simulated interference fringes based on Fourier transform

Fig. 4. Assembly diagram and its physical image

Fig. 5. Flow chart of liquid refractive index measurement program

Fig. 6. Measurement results of liquid refractive indices

Fig. 7. Time stability of measurement system at different initial fringe numbers