Results 241 to 250 of about 88,929 (292)
Some of the next articles are maybe not open access.
Liquid acoustic lens for photoacoustic tomography
Optics Letters, 2013Recently, intensive research has been conducted to accelerate the development of photoacoustic (PA) imaging modality for biomedical applications. The use of acoustic lenses to collect ultrasound signals is of great interest. This Letter presents the design and fabrication of a liquid acoustic diverging lens, which can enlarge the acceptance angle of an
Chaolong, Song, Lei, Xi, Huabei, Jiang
openaire +2 more sources
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
openaire +1 more source
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
openaire +1 more source
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
openaire +1 more source
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
openaire +1 more source
Liquid lens using acoustic radiation force
IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 2011A liquid lens is proposed that uses acoustic radiation force with no mechanical moving parts. It consists of a cylindrical acrylic cell filled with two immiscible liquids (degassed water and silicone oil) and a concave ultrasound transducer. The focal point of the transducer is located on the oil-water interface, which functions as a lens. The acoustic
Daisuke Koyama +2 more
openaire +2 more sources
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.
openaire +3 more sources
The Journal of the Acoustical Society of America, 1981
A cabinet for improving the sound output of an amplifier including an upright housing with a speaker mounted on the front, the front having one or more baffle openings, a device herein called a sound lens inserted in the baffle opening, the vibration of the speaker serving to induce vibration of the sound lens by condensation and rarefaction, by the ...
openaire +1 more source
A cabinet for improving the sound output of an amplifier including an upright housing with a speaker mounted on the front, the front having one or more baffle openings, a device herein called a sound lens inserted in the baffle opening, the vibration of the speaker serving to induce vibration of the sound lens by condensation and rarefaction, by the ...
openaire +1 more source
Cylindrical acoustic Luneburg lens
2014 8th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics, 2014We developed a two-dimensional acoustic Luneburg lens by changing the density of the medium inside the lens. The lens has a cylindrical shape and composes of about seven hundred aluminum columns with various radii of less than 2cm. It has 15 layers and the diameter of the lens is 60cm.
openaire +1 more source
Analysis of Acoustic Fields from Acoustic Convex Lens
Japanese Journal of Applied Physics, 2004In order to give a wide beam width characteristic to a vibrating element, acoustic convex lenses were fabricated and the diverged acoustic field was investigated experimentally. To design the acoustic lenses, an acoustic field estimation method was proposed by using an angular spectrum method.
In-Jin Song +4 more
openaire +1 more source
Electrically steered acoustic lens
The Journal of the Acoustical Society of America, 1999This invention is a composite acoustic lens that can be steered internally through electrical control. It can collect and direct acoustic energy from a plane wave to focus it on a transducer. It can also take the nearly omnidirectional output from a standard acoustic transducer and direct its energy in a plane wave.
openaire +1 more source
Log-periodic acoustic lens–acoustic filter plate study
The Journal of the Acoustical Society of America, 1978Graphical comparative experimental data is presented showing the variation of the useful aperture diameter, directivity index, and beamwidth as a function of frequency for an acoustic lens alone and for an acoustic lens–acoustic filter plate combination.
Robert L. Sternberg +2 more
openaire +1 more source