We numerically and experimentally demonstrate an optical image processing technique in the form of edge detection ofan object by exploring the angular selectivity of dielectric metasurfaces. By taking the advantages of resonant dielectricmetasurfaces with spatial dispersion property, we efficiently filter-out the lower k-vector components of an image andonly allow the higher k-vectors resulting in displaying the silhouettes of an object. We have considered dielectricamorphous silicon (a-Si) nanodisk with hexagonal structure interface which provides nearly zero transmission for lowerk-vectors and near-unity transmission for higher k-vectors at the operating wavelength of 1550 nm. The proposedmetasurface has been fabricated using electron beam lithography followed by a lift-off process. Our results suggest anew way to realize the effective edge detection with dielectric metasurfaces and open new opportunities for ultracompactoptical image processing devices, having various applications in microscopy.
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