[en] Principles of calculating the resolution function for the time-of-flight spectrometer in the inverse geometry for neutron inelastic incoherent scattering are described. Experimental characteristics of the fast and thermal neutrons time distributions in the IBR-2 pulsed reactor are similar to empirical functions. The transmission function for the collimator and monochromator systems is approximated by the Gram-Charlier approximation. It permits to calculate analytically most convolution integrals appearing in the resolution function