A circular variable filter is an interference filter, where the thickness of the interference layer varies along an arc. For the CVF implemented in SHARP II+, the intrinsic resolution -- the area of the CVF used to measure the transmission curve is small compared to a resolution element and the beam divergence is negligible -- and its transmission are listed in table 2.4 for 3 wavelengths.
Table 2.4: Intrinsic Resolution and transmission of
the CVF
Because the transmitted area of the CVF within the SHARP II+ camera is of finite size, the achieved spectral resolution (summarized in table 2.5) is somewhat smaller than the intrinsic resolution.
Table 2.5: Resolution of the CVF in SHARP II+