Point Spread Function of Optical Systems Apodized by Semicircular Array of 2D Aperture Functions with Asymmetric Apodization

Abstract

The simultaneous suppression of sidelobes and the sharpening of the central peak in the process of diffraction pattern detection based on asymmetric apodization have been investigated. Asymmetric apodization is applied to a semicircular array of two-dimensional (2D) aperture functions, which is a series of 'coded-phase arrays of semicircular rings randomly distributed over the central circular region of a pupil function' and is similar to that used in the field of diffractive optics. The point spread function (PSF) of an imaging system with asymmetric apodization of the discrete type has been found to possess a good side with suppressed sidelobes, whereas its bad side contains enhanced sidelobes. Further, the diffracted field characteristics are obtained in the presence of these aperture functions. Asymmetric apodization is helpful in improving the performance of the optical gratings or 2D arrays used in real-time imaging techniques.

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

“…The focal point of a high-aperture focusing system can also be reduced by employing vortex phase functions [15,16]. A substantial number of studies have been conducted on asymmetric apodization [17][18][19][20][21]. In confocal scanning systems or optical imaging systems, asymmetric apodization is used to achieve axial and lateral resolution.…”

Corollaries of Point Spread Function with Asymmetric Apodization

“…All these studies are significant breakthrough in asymmetric apodization studies. Based on their studies Reddy and Sagar [4] applied the concept of asymmetric apodization to semicircular arrays of circular pupil functions and they achieved improved side-lobe suppression. Reddy and Sagar [5] introduced semicircled energy factor for analyzing the flux distribution in the image plane of optical systems with phase-only pupil.…”

“…A few earlier studies in this case are limited [12][13][14][15]. Earlier studies [1][2][3][4][5][6] are the basis for current investigation. The present study on corollaries of the PSF of an asymmetric optical imaging system enables us to know the effects of asymmetric apodization on the consequences like increase in resolution in the Sparrow criterion, decrease in full width half maximum (FWHM), and so forth.…”

Spherical Aberration of Point Spread Function with Asymmetric Pupil Mask

“…This method can change the performance of an optical imaging system by redistributing the light flux in the image plane. There has been a certain number of investigations involving asymmetric apodization for different considerations, that is, improvement of side-lobe suppression [1,2], application of asymmetric apodization to linear arrays and circular arrays [3,4] to improve the axial resolution of the optical system [5,6], reduction of Sparrow resolution limit with incoherent illumination [7] to achieve axial and lateral resolution in confocal imaging [8] and to detect the extra solar planets [9], and improvements of dispersion of chirped fiber gratings [10]. In these studies the optical system has asymmetrically apodized.…”