On estimation of optical properties in near infrared spectroscopy with use of cumulative distributions of times of flight of photons

This paper will focus on the estimation of the absorption and scattering coefficients based on the analysis of the superposition of cumulative distributions of times of flight of photons. This approach allows for detailed analysis of small variations in characteristics of times of flight of photons caused by a non-homogeneous media. The method presented, which is based on the variation of statistical minimum distance estimation is compared to the method of statistical moments as well as to the standard curve fitting methods. The method is analyzed by fitting the results of the theoretical models such as the ones obtained from Monte-Carlo simulations of light propagation to the data from the simulated measurements. This allows the estimation of the optical parameters despite the noise in the measured signal and the systematic constant time shift from the instrumentation. The method is implemented using Open Computing Language framework for efficient calculation on heterogeneous computers. The theoretical results are validated on the data obtained from the simulated measurements of times of flight of photons on optically turbid phantoms mimicking tissues.