Partial reflection dielectric coatings which are used for beam splitting of ultrafast pulses at various ratios requires more broadband response than typical ones and optimization for group delay dispersion (GDD). They could be produced at various angles of incidence, wavelengths or wavelength ranges with optimized group delay dispersion for various femtosecond applications.  

GDD values of non-normal incidence beam splitting coatings can be optimized for both S and P polarizations as well as for either transmitted or reflected light. GDD values for all beam splitting coatings would be in the range of 0-30 fs².

Tolerances for beam splitting ratios depend on partial reflection coefficient selection, most accurate (up to 0.5 % divergence) beam splitting ratios are obtained for high reflection beam splitting coatings (from 90 % to 99 %).