Equilateral Prisms are used routinely as dispersing elements where spectral separation is required. They provide better brightness (lower stray light) than diffraction gratings. They also have greater power handling capabilities and avoid possible confusion when trying to interpret overlapping spectral orders. It must be remembered that dispersion is non-linear with wavelength and that surface reflection losses may affect throughput. Ealing offers Equilateral Prisms in three materials designed to suit a wide variety of dispersion, wavelength, and surface reflection requirements. In general, a higher refractive index material produces greater angular separation.