Annular circular aperture: intensity maxima and minima on the optical axis.
The positions of the first three minima (zeros) and secondary maxima of the intensity on the optical axis for a diffraction-limited optical system with annular circular exit pupil are calculated for several values of obscuration ratio. The permissible depth of focus of these systems and the intensity maxima and minima on the optical axis for a diffraction-limited optical system with a multiple annular circular exit pupil are also given.