Summary: The influence of the refractive dispersion on \(CdP_2\) substrate on spectral characteristics of existing optical filters and in the process of optimization of filter parameters are studied. It is found that for a cut-off filter of \(S-BHB\dots BHB\) type, narrow-band filter of \(S-BHB\dots 2B\dots BHB\) type and wide-band filter of \(S-2BH2B\dots 2BH2B\) type the influence of dispersion is small and for optical filters with optimal selection of parameters the deviation may be 0.5-1% in some parts of the spectrum.