Results 251 to 260 of about 15,272 (279)
Some of the next articles are maybe not open access.
Development Of The Acoustic Lens
SPIE Proceedings, 1988The ability to "see" underwater is critical to underwater navigation, target detection, target identification, tracking and particularly protection of valuable access against potential saboteurs. From available open literature, it seems that underwater imaging development peaked in the 1960's and early 1970's.
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Acoustic cavity modes in lens-shaped structures
The Journal of the Acoustical Society of America, 2003A method for solving exactly the Helmholtz equation in parabolic rotational coordinates is presented using separability of the eigenfunctions and the Frobenius power series expansion technique. Two examples of interest in acoustics are considered and analyzed quasianalytically: The acoustic pressure in a cavity defined by two paraboloids (forming a ...
Willatzen, Morten, Lew Yan Voon, L.C.
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An engineered acoustic lens for a narrow acoustic jet generation
Applied Physics Express, 2022Abstract Herein, we numerically investigate novel engineered shell structures immersed in water to generate narrow acoustic jets (AJs). In our simulations, acrylonitrile butadiene styrene and polylactic acid, two kinds of 3D printing materials, are selected for designing acoustic lenses. The engineered cylindrical shell with a cross or a
Song Zhou, Yalin Wang, Zhong Chen
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The Journal of the Acoustical Society of America, 1994
An acoustic lens system is constructed so that at least one surface of acoustic lenses constituting the acoustic lens system is an aspherical surface, which has such a shape that curvature moderates progressively in separating from the axis of the acoustic lens system, and an acoustic beam stop is provided therein.
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An acoustic lens system is constructed so that at least one surface of acoustic lenses constituting the acoustic lens system is an aspherical surface, which has such a shape that curvature moderates progressively in separating from the axis of the acoustic lens system, and an acoustic beam stop is provided therein.
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The Journal of the Acoustical Society of America, 1984
A lens structure is disclosed for a transducer that is utilized to transmit pulses of alternating pressure waves into the body of a patient and produce signals in response to reflections from the body. The lens is comprised of a first lens element having a concave face facing the crystals and a second lens element filling the space between.
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A lens structure is disclosed for a transducer that is utilized to transmit pulses of alternating pressure waves into the body of a patient and produce signals in response to reflections from the body. The lens is comprised of a first lens element having a concave face facing the crystals and a second lens element filling the space between.
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The Journal of the Acoustical Society of America, 1992
In an acoustic lens apparatus of this invention, a lens surface formed on an ultarsonic medium has a longitudinal wave lens portion constituted by a first aspherical surface at its central area, and a transverse wave lens portion constituted by a second aspherical surface at its peripheral area. The ultrasonic medium includes a piezoelectric transducer
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In an acoustic lens apparatus of this invention, a lens surface formed on an ultarsonic medium has a longitudinal wave lens portion constituted by a first aspherical surface at its central area, and a transverse wave lens portion constituted by a second aspherical surface at its peripheral area. The ultrasonic medium includes a piezoelectric transducer
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Nonspherical acoustic lens study
The Journal of the Acoustical Society of America, 1976A successful short focal length radar lens design technique was adapted to the problem of nonspherical thin underwater acoustic lens development and construction. The motivation was furnished by the many sonar requirements for small size lenses capable of operation in a scanning mode.
Kevin T. Corbett +2 more
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Acoustic Lens and Ultrasonic Probe Using the Lens
The Journal of the Acoustical Society of America, 2011The invention has a structure, in an acoustic lens for an ultrasonic probe comprising leg portions which are connected by a planar shape, and a lens portion which is provided on the leg portions and has curvature in the lengthwise direction, wherein the leg portions are made from an attenuation prevention material having the less ultrasonic propagation
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Acoustic Field in a Luneberg Lens
The Journal of the Acoustical Society of America, 1967A Luneberg lens, which is a perfectly focusing omnidirectional spherical lens, has been subjected to a wave analysis. Plane radiation incident on a fluid lens was assumed. The separability of the scalar Helmholtz equation for the lens region permits the representation of the internal acoustic field as an expansion in Legendre polynomials and radial ...
G. E. Lord, H. R. Feldman
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The Journal of the Acoustical Society of America, 1970
An acoustic compound design fulfilling the aperture and resolution requirements of the quartz-plate Solkolov acoustic image converter is described. Details of the lens construction and images obtained from its operation are presented.
J. L. DuBois, W. Rosenblum, R. Gilmore
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An acoustic compound design fulfilling the aperture and resolution requirements of the quartz-plate Solkolov acoustic image converter is described. Details of the lens construction and images obtained from its operation are presented.
J. L. DuBois, W. Rosenblum, R. Gilmore
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