Isothermal nucleation-growth phenomena in 2D semicrystalline polymer films have been investigated by the time-resolved two-dimensional fast Fourier transform (2DFFT) as a quasi-scattering method via real-time in situ observation and measurements. The dynamic evolution of the structure function has been used to interpret the observed scattering intensity connected with crystallization kinetics. The important dynamic quantities, such as the intradomain scattering (domain-size distribution) and spatial distribution of nuclei, have been distinguished by the analysis of the power spectra for different crystallization conditions. The interdomain interference (spatial correlations) was interpreted by the aid of a pair correlation function. Experimental data confirm Pored＇s law, that is, the q(-4) dependence of the tails. A scaling relation of the structure function is found experimentally for the free growth of domains during the postnucleation Stage; however, it is not valid after impingement occurs.