Determination of the point spread function of layered metamaterials assisted with the blind deconvolution algorithm

Abstract

We propose to use the blind deconvolution and its modification to extract the point spread function (PSF) of layered metamaterials from a SNOM measurement. The measurement results are processed using the blind deconvolution algorithm to reconstruct the real-valued non-coherent PSF, or using the modified blind deconvolution introduced in this paper to reconstruct the complex-valued coherent PSF. The two algorithms are tested in simulations with a layered metamaterial deposited on a thin metallic mask with test apertures. We show that the modified algorithm is capable of recovering the approximate shape of complex PSF with a sub-wavelength full width at half maximum from a measurement in which the apertures are larger than the wavelength.

Convex optimization-based blind deconvolution for images taken with coherent illumination

“…We implemented an ADMM algorithm in MATLAB to compute the updates in Algorithm 1. Although this allows for parallel computations of rtd SVDs with complexity Omax mn, pq 3 , where d is the number of images taken, and rtd SVDs with complexity O1, we computed these in series. Due to the computational complexity, we tested the algorithm for two cases with small dimensions.…”

“…In application areas such as coherent diffraction imaging (CDI) [1], long-range horizontal imaging [2], imaging of layered metamaterials [3], or ptychography [4], the image formation process can be described using the expressions for imaging with coherent illumination [5]…”

P‐76: Adaptive Phase‐Correction Scheme for Enhancing the Sensing Image Quality of an Ultrasonic Fingerprint‐Sensor Integrated OLED System

“…The diffraction is the main cause of interference patterns which greatly influences the fingerprint image quality. The diffracted image can be usually corrected by convolving the specific point spread function (PSF) in previous studies [4][5][6]. However, the mentioned method has a problem in that each suitable function must be applied depending on the applied structure.…”