Science Daily May 14, 2024 An important hurdle for using metalenses for manipulating waves is due to the severe hampering of the angular response originating from coma and field curvature aberrations, which result in a loss of focusing ability. Researchers in South Korea developed a blueprint by introducing the notion of a wide field-of-hearing (FOH) metalens, designed particularly for capturing and focusing sound with decreased aberrations. Employing an aberration-free planar-thin metalens that leverages perfect acoustic symmetry conversion, they experimentally realized a robust wide FOH capability of approximately 140 deg. in angular range. The metalens featured a relatively short focal length, […]
Tag Archives: Metalenses
Meta-lens offers superior off-axis focus
Phys.org October 24, 2022 After experimentally studying the optical properties of dielectric reflective metalenses including their off-axis focusing performance, researchers in Saudi Arabia proposed reflective metalens based on titanium dioxide (TiO2) and silicon dioxide (SiO2), which operate at a visible wavelength of 0.633 µm. Unlike conventional reflective metalenses based on metallic mirrors, the proposed device was designed based on a modified parabolic phase profile and was integrated onto a dielectric distributed Bragg reflector periodic structure to achieve high reflectivity with five dielectric pairs. The focusing efficiency characteristics of the metalens were experimentally studied for beam angles of incidence between 0∘ […]