Defocused point spread function of asymmetrically apodized optical imaging systems with slit apertures

Andra Naresh Kumar Reddy (Login required)
Science and Research Laboratory of Automated Systems of Science Researches, Samara National Research University, Russia
Department of Physics (H&S), CMR Institute of Technology, Telangana, India

Dasari Karuna Sagar
Department of Physics, University College of Science, Osmania University, Hyderabad, India

Paper #3046 received 2016.05.28; revised manuscript received 2016.09.05; accepted for publication 2016.09.29; published online 2016.09.30.

DOI: 10.18287/JBPE16.02.030302


In the presence of defocusing, the PSF of an optical imaging system with asymmetric apodization have been investigated analytically. The asymmetry in the PSF has been observed to increase with edge strip width (b) of the slit aperture and further improved by defect of focus in the image plane, permits to achieve a significant improvement in side-lobe suppression. The proposed analytical model of pupil function considers these effects and formulates a space-variant PSF is obtained by employing asymmetric apodization. The optimum values for asymmetric apodization controlling parameter (b) and defocusing parameter (Y) at which results in smoothing the central peak shape and reducing optical side-lobes intensity on one side of the Asymmetric PSF termed as ‘good’ side at the cost of worsening its counterpart known as ‘bad side’ with which renders the resolution of apodized optical imaging systems. In order to simplify the proposed analytical design an efficient method is derived and evaluated.


Defocusing; diffraction; asymmetric apodization; two-line resolution; Point spread function; complex pupil function

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