Estimation of Circularly Symmetric Point Spread Function for Digital Auto-Focusing

In this paper, we present a circularly symmetric point spread function (PSF) estimation technique for a fully digital autofocusing system. The proposed algorithm provides realistic, unsupervised PSF estimation by establishing the relationship between the one-dimensional ideal step response and the corresponding two-dimensional circularly symmetric PSF. Main advantage of the proposed algorithm is the accurate estimation of the PSF combining by using interpolation, feasible step response estimation. The proposed estimation method will serve as (i) a fundamental procedure in designing an in-house extended depth-of-field (EDoF) system, (ii) a detecting method for improperly manufactured imaging sensors in the production line, and (iii) a PSF estimation method for general image restoration algorithms.