Abstract
In this research we have been studied the 3rd order spherical aberration for an optical
system consisted of obscured circular aperture with non central circular obscuration
through the calculation of point spread function (P.S.F) in presence of the obscuration
in the center and comparing the obtained results with that results of moving
obscuration far away from the center, where the results showed significant
improvement for(P.S.F) value. The study was done of different obscurities ratios in
addition to the different 3rd order spherical aberration values |