Conventional ultrasound transducers used for medical diagnosis generally consist of linearly aligned rectangular apertures with elements that are focused in one plane. While traditional beamforming is easily accomplished with such transducers, the development of quantitative, physics-based imaging methods, such as tomography, requires an accurate, and computationally efficient, model of the fie...

In this paper, a half-wave plate (HWP) based on birefringent metamaterial is numerically designed to operate in the visible range. The proposed structure consists of an array double-pattern perpendicular rectangular apertures (RAA) engraved into opaque silver film deposited glass substrate. One filled. operating principle excitation and propagation one guided mode inside each aperture but with ...

Transmission through sub-wavelength apertures in perfect metals is expected to be strongly suppressed. However, by structural engineering of the apertures, we numerically demonstrate that the transmission of transverse electric waves through periodic arrays of subwavelength apertures in a thin metallic film can be significantly enhanced. Based on equivalent circuit theory analysis, periodic arr...

This work focuses on the study of shield systems consisting nested enclosures. In first step, using FDTD simulations and measurements in an anechoic chamber, we investigate shielding effectiveness (SE) system two rectangular enclosures frequency range up to 3 GHz. It is shown for time that a number frequencies, SE shields can be improved by 40–50 dB due asymmetric arrangement enclosures, their ...

Purpose We improve the intraocular open-capsule devices (IOCD) for the prevention of posterior capsule opacification (PCO). Methods A total of 45 New Zealand rabbit eyes were divided into six similar groups after crystalline lens evacuation. Each group was implanted with a hydrophilic intraocular lens (IOL) and a hydrophilic IOCD of different designs. In the first experiment (Part A), a squar...

Abstract To improve exclusion systems for fruit trees, insect nets of various types were evaluated their permeability to different beneficial and pest species, under laboratory field conditions. Pests studied the apple maggot, Rhagoletis pomonella (Diptera: Tephritidae) spotted wing drosophila, Drosophila suzukii Drosophilidae). Beneficials Aphidoletes aphidimyza Cecidomyiidae), Aphidius matric...

Abstract Optical metasurfaces are perfect candidates for the phase and amplitude modulation of light, featuring an excellent basis holographic applications. In this work, we present a dual scheme based on photon sieve principle, which is then combined with hologram by utilizing Pancharatnam–Berry phase. We demonstrate that two types apertures, rectangular square shapes in gold film filled silic...