The optical constants for polymerized cholesteric liquid crystal (CLC) films were obtained by comparing theoretical transmittance and reflectance spectra with measured ones. The theoretical spectra were calculated using an exact solution for a cholesteric layer within the Berreman 4 x 4 matrix formalism. We applied the curve-fitting method to three CLC samples with different reflection hands and compared the fitted results with the measured refractive indices for a parallel-aligned LC sample.