Monte Carlo method in optical radiometry

State-of-the-art in the application of the Monte Carlo method (MCM) to the computational problems of optical radiometry is discussed. The MCM offers a universal technique for radiation transfer modelling based on the stochast ic approach. Developments of the original MCM algorithms and software for c alculation of effective emissivities of black bodies, absorption characteri stics of cavity radiometers and photometric properties of integrating spher es are used for designing advanced optical instruments. The capabilities of the developed software are illustrated by several examples. The techniques of convergence improvement and special time-saving algorithms are outlined .