Results 31 to 40 of about 13,611 (164)
Acoustic Forceps Based on Focused Acoustic Vortices with Different Topological Charges
Sensors, 2023 For enhanced energy concentration with improved flexibility for object manipulation, a focused acoustic vortex (FAV) is designed using a sector planar piston transducer array and acoustic lens that can produce the effective concentration of the acoustic ...
Libin Du +3 more
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International Journal of Smart and Nano Materials, 2015 We investigate the use of graded inhomogeneities in order to enhance the focusing and collimation performance of structure-embedded acoustic metamaterial lenses.
H. Zhu, F. Semperlotti
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Optical and acoustic super-resolution imaging in a Stampfli-type photonic quasi-crystal flat lens
Results in Physics, 2021 Super-resolution imaging has been separately realized with two-dimensional photonic and phononic quasi-crystal flat lenses for the past few decades, but they are still utilized for independent disciplines.
Hexiang Zhao, Jianlan Xie, Jianjun Liu
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Lens Geometries for Quantitative Acoustic Microscopy [PDF]
, 1995 The purpose of the first Lemons-Quate acoustic microscope(1) was to image the surfaces of materials or biological cells with a high resolution. Unfortunately, competition with the optical microscope was only partially successful due to the high degree of absorption in the liquid-coupling medium at high frequencies.
Atalar, Abdullah +3 more
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Experiments on frightening effects to fish by underwater sound emitters for diversion from dangerous areas of reservoirs [PDF]
Caspian Journal of Environmental SciencesLarge reservoirs have areas dangerous for fish. For instance, water intake facilities, hydroelectric dams, etc. Therefore, it becomes necessary to protect or divert fish from such areas. One way to achieve this is to use loud underwater sound.
Artur Tumenov +4 more
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Design and Fabrication of Double-Focused Ultrasound Transducers to Achieve Tight Focusing
Sensors, 2016 Beauty treatment for skin requires a high-intensity focused ultrasound (HIFU) transducer to generate coagulative necrosis in a small focal volume (e.g., 1 mm3) placed at a shallow depth (3–4.5 mm from the skin surface).
Jihun Jang, Jin Ho Chang
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Parametric Acoustic Lens Sonar [PDF]
The Journal of the Acoustical Society of America, 1974 Sum and difference frequency parametric arrays are usually generated in the field of relatively large planar electroacoustic transducers by the transmission of two high-frequency primary waves. The approach taken in the present paper utilizes one or more small transducers located on the focal surface of a relatively large acoustic lens. Upon projection,
T. G. Muir, D. L. Folds
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Wavelength-scale gas-filled cuboid acoustic lens with diffraction limited focusing
Results in Physics, 2019 Per the laws of geometrical optics, a plane-parallel medium does not possess focusing properties. However, in this paper, we demonstrate for the first time that an acoustic cuboid particle filled with CO2 is able to focus sound despite its flat surface ...
Constanza Rubio +4 more
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, 2004 A survey of acoustic devices for focusing airborne sound is presented. We introduce a new approach to design high quality acoustic lenses based on arrays of cylindrical rigid scatterers in air. A population based stochastic search algorithm is used in conjunction with the multiple scattering theory to optimize a cluster of cylinders that focuses the ...
Hakansson, Andreas +2 more
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A new directional acoustic lens: V-groove lens [PDF]
1993 Proceedings IEEE Ultrasonics Symposium, 1993 A new directional acoustic lens is introduced. The geometry is very similar to the line-focus lens except the lens cavity, which is shaped as a groove with flat-bottom V cross section. The slanted planar edges of the groove are inclined in order to generate waves incident on the object surface at a critical angle.
Bozkurt, Ayhan +3 more
openaire +2 more sources