Edge imaging characteristics of aberrated coherent optical systems by edge masking of circular apertures

Abstract

In this paper, attempts have been made to study the joint effects of apodization and aperture masking on the diffraction images of coherently illuminated straight edge. The Edge-Ringing, Edge-Shift and Edge-Eradient of the edge images have been evaluated for different values of apo-dization using edge masking of circular apertures. We have considered rotationally symmetric, ab-errated coherent optical system. These investigations have lead to the use of certain pupil functions in conjunction with optimal apodizers to assess the quality of edge images. Any obstruction placed in the light path of an optical system prevents waves from a portion of the wavefront in reaching the focal zone. This results in the change in the light flux at every point of the diffraction pattern. This is in turn, depends on the shape and size of the obstruction.

Engineering of Aberrated PSF by Asymmetric Apodization with the Complex Shaded Aperture

“…It is evident that asymmetric apodization alters the distribution of light flux enclosed in the diffraction pattern and provides the resolution of an optical system [22]. PSF engineering is the manipulation of light distribution in the focal region of an optical system and is used to improve the performance of optical systems for many applications [23][24][25]. This approach modifies the size of the focal spot and the level of its neighboring side-lobes, as demonstrated by inserting an appropriate phase filter, amplitude filter, or both in the Fourier plane of the given optical system [26][27][28][29].…”

Point Spread Functions of aberrated Leaky annular apertures with defocus

“…To avoid edge-ringing in coherent and partially coherent illuminations, it is desirable to build a system that produces actual and positive amplitude impulse. This problem has been investigated, and it has been determined that proper apodizer can control edge-ringing [12][13][14]. In the absence and presence of aberrations, aperture shaping reduces the negative effects of edge-ringing in coherent image.…”

Mitigation of Edge Ringing for the Optimization of Highly Aberrated Coherent Optical Systems

“…Building a system that produces actual and positive amplitude impulses is desirable to avoid edgeringing in coherent and partially coherent illuminations. This problem has been investigated, and determined that a proper apodizer can control edge-ringing [14][15][16]. In the absence and presence of aberrations, aperture shaping reduces the negative effects of edge-ringing incoherent images.…”