Methods investigation to determine optical constants of liquid based on transmittance and reflectance spectrum

The particle swarm optimization (PSO) was introduced to calculate optical constants of liquid based on transmittance and reflectance spectrum. Two methods, namely as particle swarm double-thickness transmittance method (PTT) and particle swarm transmittance and reflectance method (PTR), were developed by combining the PSO with the spectrometry. The comparative study of two methods was carried out with distilled water as the research object, and the experimental deviation of the two methods was evaluated. The results show that the two methods are reliable for solving optical constants of liquid with high resolution accuracy, even existing experimental deviation. Meanwhile, a deviation correction method proposed in present work reduces the effect of uneven experimental deviation on the accuracy of the two methods.