The Effect Of Focus Error And Spherical Aberration On Sharp Edge Image Intensity

Abstract

This research has been carried out to determine the distribution of the intensity in the image of object with a Sharp-Edge using coherent illumination. In this research, a special formulas have been derived called the Edge spreads Function (ESF) .This formula is very useful for theoretical and practical studies since it is applicable to system with any kind and amount of aberrations that are present in the optical systems by using pupil function technique.
 Also optimum balance values for each kind of aberration were determined, these values have been used in programs prepared specially for calculating (ESF) using quick basic programming language with Simpson method for numerical integrals in order to calculate the intensity of different quantities of aberrations such as focus error and spherical aberration (first, Third, fifth – orders) . As well as the effect of Apodization upon the image of sharp Edge object resulting from an optical system operating with a small circular aperture.
 The main aim of this research is testing the Optical Systems which use Coherent light and make decision of this Systems validity range. we found that using the exit pupil technique is useful to calculate the complex intensity also the analysis capability when using coherent light is better than the incoherent light and the relation between the focus error and the quantity of aberration.