Journal articles: 'Acoustic wave diffraction'

1

Devaney, Anthony J. "Acoustic wave diffraction tomography." Journal of the Acoustical Society of America 110, no. 5 (November 2001): 2659. http://dx.doi.org/10.1121/1.4777061.

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Belyi, V. N., P. A. Khilo, N. S. Kazak, and N. A. Khilo. "Some features of acousto-optic interaction of optical and acoustic Bessel beams in transversely isotropic optically positive crystals." Proceedings of the National Academy of Sciences of Belarus. Physics and Mathematics Series 55, no. 4 (January 7, 2020): 479–88. http://dx.doi.org/10.29235/1561-2430-2019-55-4-479-488.

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Some basic properties of acousto-optical (AO) diffraction involving Bessel light and acoustic beams in anisotropic crystals are investigated. Hexagonal symmetry crystals are considered and are optically uniaxial and positive and acoustically transversely isotropic. It is shown that, unlike the case of AO diffraction of plane waves, the transition to Bessel beams allows one to realize a number of new diffraction channels having specific configurations of the wave vectors of interacting waves while maintaining the axial symmetry of the optical scheme as a whole. The diffraction channels for anisotropic scattering are classified and the main parameters of the scattered Bessel light beam and the parameters of the Bessel acoustic beam are calculated for each of them. The possibility of implementing the isotropic-type diffraction was revealed, which makes it possible to increase the efficiency of AO conversion. The parameters of this-type diffraction are determined for two scattering channels, namely, for scattering by a direct Bessel acoustic beam and by a backward propagating acoustic beam.Due to the appearance of a set of scattering channels and with regard to the fact that Bessel light and acoustic beams have helical wave front dislocations, as well as suppressed diffraction spreading, the study of the features of AO diffraction of such beams in optically positive crystals has both a scientific and practical interest.

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Wijewardena Gamalath, K. A. I. L., and G. L. A. U. Jayawardena. "Diffraction of Light by Acoustic Waves in Liquids." International Letters of Chemistry, Physics and Astronomy 4 (September 2013): 39–57. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.4.39.

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For the acusto-optic interactions in liquids, an equation for the diffraction light intensity was obtained in terms of Klein Cook parameter Q. With optimized parameters for Q, incident light wave length of λ = 633 nm, sound wave length of Λ = 0.1 mm, acusto-optic interaction length L=0.1 m, and refractive index of the liquid in the range of 1 to 2, the existence of ideal Raman-Nath and Bragg diffractions were investigated in terms of phase delay and incident angle. The ideal Raman-Nath diffraction slightly deviated when the Klein Cook parameter was increased from 0 to 1 for low phase delay values and for large phase delay, the characteristics of the Bessel function disappeared. Higher value of Klein Cook parameter gave Bragg diffraction and ideal Bragg diffraction was obtained for Q ~100. A slight variation of the incident angle from Bragg angle had a considerable effect on Bragg diffraction pattern. Klein Cook parameter with the change of acoustic wave frequency was investigated for liquids with refractive index in the range1.3-1.7 and their diffraction patterns were compared with practically applicable acusto-optic crystals. For acusto-optic diffractions in liquids, sound velocity plays an important role in Bragg regime with Q increasing with increasing acoustic frequency. As acoustic wave frequency exceeded 10 MHz most of the liquids reached Bragg regime before these crystals.

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Minin, Igor, and Oleg Minin. "Mesoscale Acoustical Cylindrical Superlens." MATEC Web of Conferences 155 (2018): 01029. http://dx.doi.org/10.1051/matecconf/201815501029.

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We demonstrate experimentally for the first time the acoustojet (acoustic jets) formed from acoustic plane wave scattering by a penetrable cylindrical particle with dimensions of several wavelengths. It acts as a superlens with subwavelength localization of acoustical wave. During the scattering by elastic solid particles, additional internal shear waves are excited due to modes conversion. This mechanism allows achieving sharp focusing in the near-field zone. Such mesoscale single particle cylindrical lens may be considered as acoustic metamaterials free superlenses with resolution beyond the diffraction limit.

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Devendran, Citsabehsan, Kyungyong Choi, Jongyoon Han, Ye Ai, Adrian Neild, and David J. Collins. "Diffraction-based acoustic manipulation in microchannels enables continuous particle and bacteria focusing." Lab on a Chip 20, no. 15 (2020): 2674–88. http://dx.doi.org/10.1039/d0lc00397b.

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We explore a unique diffractive acoustic phenomenon arising from a surface acoustic wave and channel elements, which we term diffractive acoustic surface acoustic waves (DASAW), which can be applied robustly for all channel orientations.

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Uzair, Mohammad, Xiao Li, Yangyang Fu, and Chen Shen. "Diffraction in phase gradient acoustic metagratings: multiple reflection and integer parity design." INTER-NOISE and NOISE-CON Congress and Conference Proceedings 263, no. 3 (August 1, 2021): 3167–75. http://dx.doi.org/10.3397/in-2021-2320.

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Diffraction occurs when acoustic waves are incident on periodic structures such as graded metasurfaces. While numerous interesting diffraction phenomena have been observed and demonstrated, the underlying mechanism of diffraction in these structures is often overlooked. Here we provide a generic explanation of diffraction in phase gradient acoustic metagratings and relate high-order diffractions to multiple reflections in the unit cells. As such, we reveal that the number of unit cells within the metagrating plays a dominant role in determining the diffraction patterns. It is also found that the integer parity of the metagrating leads to anomalous reflection and refraction with high efficiency. The theory is verified by numerical simulations and experiments on planar metagratings and provides a powerful mechanism to manipulate acoustic waves. We further extend the theory to cylindrical waveguides for the control of sound vortices via topological charge in azimuthal metagratings. The relevance of the theory in achieving asymmetric wave control and high absorption is also discussed and verified both numerically and experimentally.

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Fedoseeva, E. V., V. V. Bulkin, and M. V. Kalinichenko. "TECHNIQUE FOR ESTIMATING THE EFFICIENCY OF NOISE PROTECTIVE ACOUSTIC SCREENS IN THE PRESENCE OF FLAT ANTI-DIFFRACTORS." Akustika, VOLUME 40 (2021): 22–28. http://dx.doi.org/10.36336/akustika20214022.

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To increase the efficiency of acoustic screens when protecting against acoustic noise, anti-diffractors are used to reduce the diffraction level on the upper edge of the screen. The aim of the work is to refine the mathematical model used to assess noise protection efficiency with the help of an acoustic screen with an installed one-sided flat-type anti-diffractor. The well-known techniques based on the principle of the amplitude dependence of the sound wave intensity from two sources are analyzed: a point-type noise source and a secondary cylindrical wave source - the screen edge, on which the sound wave is diffracted. Taking into account that the change in the distance between the anti-diffractor and the working point in the acoustic shadow zone is associated with a change in the diffraction angle, it is proposed to evaluate the acoustic screen effectiveness by comparing the initial sound wave propagation paths. An approach to a mathematical calculation model formation is proposed, in which the diffraction point located at the intersection of two components of the wave path to the operating point is considered to be the location of the sound wave secondary source in the area of the screen upper edge: from the noise source to the flat-type anti-diffractor installed on the upper edge of the screen, and from the anti-diffractor rear edge to the operating point. Relationships that make it possible to solve the problem of analytical assessment of noise-protective acoustic screens' effectiveness when installing anti-diffractors on their upper face in the form of flat hinged panels oriented towards the acoustic shadow are obtained.

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8

Hakiri, Kentaro, Masashi Suzuki, and Shoji Kakio. "Acousto-optic Bragg diffraction using longitudinal leaky surface acoustic wave." Japanese Journal of Applied Physics 57, no. 7S1 (April 20, 2018): 07LD01. http://dx.doi.org/10.7567/jjap.57.07ld01.

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9

WANG ZUO-QING, WANG CHENG-HAO, and ZHOU SU-HUA. "EXTRAORDINARY BRAGG DIFFRACTION OF SURFACE ACOUSTIC WAVE ON ACOUSTIC GRATING." Acta Physica Sinica 37, no. 3 (1988): 379. http://dx.doi.org/10.7498/aps.37.379.

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10

Vadilonga, Simone, Ivo Zizak, Dmitry Roshchupkin, Emelin Evgenii, Andrei Petsiuk, Wolfram Leitenberger, and Alexei Erko. "Observation of sagittal X-ray diffraction by surface acoustic waves in Bragg geometry." Journal of Applied Crystallography 50, no. 2 (March 14, 2017): 525–30. http://dx.doi.org/10.1107/s1600576717002977.

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X-ray Bragg diffraction in sagittal geometry on a Y-cut langasite crystal (La3Ga5SiO14) modulated by Λ = 3 µm Rayleigh surface acoustic waves was studied at the BESSY II synchrotron radiation facility. Owing to the crystal lattice modulation by the surface acoustic wave diffraction, satellites appear. Their intensity and angular separation depend on the amplitude and wavelength of the ultrasonic superlattice. Experimental results are compared with the corresponding theoretical model that exploits the kinematical diffraction theory. This experiment shows that the propagation of the surface acoustic waves creates a dynamical diffraction grating on the crystal surface, and this can be used for space–time modulation of an X-ray beam.

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11

Peterie, Shelby L., and Richard D. Miller. "Near-surface scattering phenomena and implications for tunnel detection." Interpretation 3, no. 1 (February 1, 2015): SF43—SF54. http://dx.doi.org/10.1190/int-2014-0088.1.

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Tunnel locations are accurately interpreted from diffraction sections of focused mode converted P- to S-wave diffractions from a perpendicular tunnel and P-wave diffractions from a nonperpendicular (oblique) tunnel. Near-surface tunnels are ideal candidates for diffraction imaging due to their small size relative to the seismic wavelength and large acoustic impedance contrast at the tunnel interface. Diffraction imaging algorithms generally assume that the velocities of the primary wave and the diffracted wave are approximately equal, and that the diffraction apex is recorded directly above the scatterpoint. Scattering phenomena from shallow tunnels with kinematic properties that violate these assumptions were observed in one field data set and one synthetic data set. We developed the traveltime equations for mode-converted and oblique diffractions and demonstrated a diffraction imaging algorithm designed for the roll-along style of acquisition. Potential processing and interpretation pitfalls specific to these diffraction types were identified. Based on our observations, recommendations were made to recognize and image mode-converted and oblique diffractions and accurately interpret tunnel depth, horizontal location, and azimuth with respect to the seismic line.

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12

Wang, Bo, Shengdong Liu, Fubao Zhou, Jun Zhang, and Fangkun Zheng. "Diffraction Characteristics of Small Fault ahead of tunnel face in coal roadway." Earth Sciences Research Journal 21, no. 2 (April 1, 2017): 95–99. http://dx.doi.org/10.15446/esrj.v21n2.64938.

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Small fault ahead of the tunnel face in coal roadway is the important hidden hazard factor of coal and gas outburst accidents. The study of small fault prediction has important practical significance, which is the urgent demand of coal mine safety production. The diffraction of breakpoint can be used to identify the fault. However, unlike surface seismic exploration, the diffraction is with approximately horizontal incidence when the advanced detection is carried out in the roadway. The common advanced detection system is mainly as the reference of traffic tunnel, without considering the influence of low-velocity coal seam. Considering the influence of an acoustic wave of the roadway cavity and channel wave of the coal seam, the advanced detection model of small fault ahead of tunnel face is established. Diffraction advanced observation system in which sources located in front of tunnel face is constructed, and the numerical calculation of the high-order staggered-grid finite difference is carried out. The simulation results show that: Compared with the data collected by reflection observation system, in seismic records acquired by diffraction observation system, the suppression effect of acoustic wave is appeared. The diffracted P-wave of the breakpoint of component X is clear with strong energy and short-wave group. Multiple diffractions of the breakpoint are not found, but the multiple diffraction of tunnel face endpoint is obvious. The difference between breakpoint diffraction and multiple diffractions of the endpoint is clear, and diffracted P-wave of the breakpoint is easy to identify. The multiple reflected channel wave between the fault and the tunnel face is very obvious, and the reflected channel wave of small fault is so hard to identify. Migration results show that the imaging resolution of diffracted P-wave of small fault is higher than the reflected channel wave, and breakpoint location of imaging is consistent with the actual model.

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13

Sauer, W., T. H. Metzger, J. Peisl, Y. Avrahami, and E. Zolotoyabko. "X-Ray diffraction under surface acoustic wave excitation." Physica B: Condensed Matter 248, no. 1-4 (June 1998): 358–65. http://dx.doi.org/10.1016/s0921-4526(98)00265-8.

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14

Tucoulou, R., R. Pascal, M. Brunel, O. Mathon, D. V. Roshchupkin, I. A. Schelokov, E. Cattan, and D. Remiens. "X-ray diffraction from perfect silicon crystals distorted by surface acoustic waves." Journal of Applied Crystallography 33, no. 4 (August 1, 2000): 1019–22. http://dx.doi.org/10.1107/s0021889800006828.

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High-resolution X-ray diffraction measurements were carried out on ZnO/Si devices under surface acoustic wave excitation and revealed some very clear satellite diffraction peaks that are obtained from the sinusoidal modulation of the near-surface region. This experiment shows that the propagation of a Rayleigh surface acoustic wave in a perfect crystal acts as a dynamical diffraction grating. The variation of the acoustic velocity has been followed across the crystal surface from the acoustic source region (beneath the ZnO film) to the far field region (not covered by the ZnO film).

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15

TERZIĆ, MIRA. "ATTENUATION OF LASER-GENERATED ACOUSTIC SIGNALS IN LIQUIDS." International Journal of Modern Physics B 05, no. 15 (September 1991): 2563–71. http://dx.doi.org/10.1142/s0217979291001012.

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The dependence of the optoacoustic wave amplitude in liquids on propagation distance was investigated for various values of the diffraction parameter. The results of the theoretical model are discussed and the computed results are compared to the experimental data obtained from optoacoustic waves generated in water and in n-heptane by means of a hybride CO 2 laser, for rigid and free boundary conditions of the liquid. The coefficients for amplitude attenuation based solely on diffraction, i.e. diffraction attenuation coefficient, are evaluated, as are the total attenuation coefficients. A simple method to correct experimental diffraction data obtained with non-ideal liquids is proposed.

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Kotov, V. M., and S. V. Averin. "Acoustooptic Diffraction of Three-Color Radiation on a Single Acoustic Wave." International Journal of Optics 2019 (February 24, 2019): 1–5. http://dx.doi.org/10.1155/2019/4386093.

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Bragg diffraction which provides effective acoustooptic interaction of three-color radiation with a single acoustic wave at a high frequency of sound is proposed and tested in a single crystal of paratellurite at the wavelengths of λ= 0.488, 0.514, and 0.633 μm. Maximal diffraction efficiency of radiation with λ=0.633 μm at acoustic frequency of 150 MHz is 88% and that with λ= 0.488 μm and λ=0.514 μm is 60%. In diffraction efficiency range from 0 to 40% the dependence of all beams on acoustic power is the same.

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17

Fakhfouri, Armaghan, Citsabehsan Devendran, Thomas Albrecht, David J. Collins, Andreas Winkler, Hagen Schmidt, and Adrian Neild. "Surface acoustic wave diffraction driven mechanisms in microfluidic systems." Lab on a Chip 18, no. 15 (2018): 2214–24. http://dx.doi.org/10.1039/c8lc00243f.

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18

Zolotoyabko, E., E. Jacobsohn, D. Shechtman, B. Kantor, and J. Salzman. "X‐ray diffraction study of surface acoustic wave device under acoustic excitation." Journal of Applied Physics 73, no. 12 (June 15, 1993): 8647–49. http://dx.doi.org/10.1063/1.353398.

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19

Largeau, Ludovic, Ibrahima Camara, Jean-Yves Duquesne, Catherine Gourdon, Pauline Rovillain, Laura Thevenard, and Bernard Croset. "Laboratory X-ray characterization of a surface acoustic wave on GaAs: the critical role of instrumental convolution." Journal of Applied Crystallography 49, no. 6 (November 11, 2016): 2073–81. http://dx.doi.org/10.1107/s1600576716015016.

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Surface acoustic waves of micrometre wavelength travelling on a monocrystal give diffraction satellites around each Bragg peak in an X-ray diffraction diagram. By using a four-crystal monochromator, a secondary two-crystal analyser and masks reducing the footprint to the part of the crystal containing the acoustic modulation, it is possible to observe these satellites on a GaAs (001) surface using a laboratory diffractometer. The finite extension of the satellite diffraction rods and of the crystal truncation rod perpendicular to the surface leads to geometrical correction factors when convoluted with the instrumental resolution function, which had previously been ignored. The calculation of these geometrical correction factors in the framework of the kinematic approximation allows the determination of the surface acoustic wave amplitude, and the study of its attenuation and its dependence on radiofrequency power and duty cycle. The ability to perform such determinations with a laboratory diffractometer should prove useful in optimizing surface acoustic waves, which are presently used in a broad range of condensed matter physics studies.

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Lysechko, Victor, and Dozyslav Kuryliak. "Acoustic Plane Wave Diffraction from a Circular Soft Ring." Acta Acustica united with Acustica 105, no. 5 (July 1, 2019): 805–13. http://dx.doi.org/10.3813/aaa.919361.

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The paper presents the implementation of the rigorous method of analytical regularization to the canonical problem of axially-symmetric diff raction from a soft ring. The series equations of the problem are reduced to an infinite series of linear algebraic equations (ISLAE) and the technique of analytical regularization is applied. Finally, the resulting matrix equation is the ISLAE of the second kind and can be solved numerically by the truncation method with any desired accuracy. The near field in the vicinity of the aperture of the ring is presented in the form of maps of the normalised total field. The far field features of the ring are obtained and discussed. The validation of our calculation is confirmed by testing of the mode matching conditions and through the comparison of the results with those for a disc.

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Hardy, John W., and Jeffrey H. Everson. "Wavefront sensor using a surface acoustic wave diffraction grating." Journal of the Acoustical Society of America 78, no. 2 (August 1985): 822. http://dx.doi.org/10.1121/1.393083.

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22

Kotov, V. M. "Diffraction of three-colour radiation on an acoustic wave." Quantum Electronics 45, no. 7 (July 28, 2015): 654–57. http://dx.doi.org/10.1070/qe2015v045n07abeh015738.

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23

Budaev, Bair V., and David B. Bogy. "Rigorous solutions of acoustic wave diffraction by penetrable wedges." Journal of the Acoustical Society of America 105, no. 1 (January 1999): 74–83. http://dx.doi.org/10.1121/1.424595.

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Akhmedzhanov, R. Farkhad. "Measurement of acoustic wave frequency by Bragg light diffraction." Journal of the Acoustical Society of America 125, no. 4 (April 2009): 2745. http://dx.doi.org/10.1121/1.4784581.

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25

Nakagawa, Yasuhiko, Mitsuhiro Gunzi, and Shouzi Kakio. "Fabrication of Diffraction Grating Assisted by Surface Acoustic Wave." Japanese Journal of Applied Physics 34, Part 1, No. 5B (May 30, 1995): 2650–52. http://dx.doi.org/10.1143/jjap.34.2650.

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Ruiz M., Alberto, and Peter B. Nagy. "Diffraction correction for precision surface acoustic wave velocity measurements." Journal of the Acoustical Society of America 112, no. 3 (September 2002): 835–42. http://dx.doi.org/10.1121/1.1497368.

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27

Lyalinov, M. A. "Diffraction of a plane acoustic wave on an impedance cone. Surface waves." Journal of Mathematical Sciences 167, no. 5 (May 25, 2010): 651–59. http://dx.doi.org/10.1007/s10958-010-9951-8.

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Santos, Luiz Alberto, Eloise Helena Policarpo Neves, Antônio Fernando Menezes Freire, Marco Antônio Cetale Santos, Ryo Matsumoto, and Claudia M. I. Ajus. "Diffraction velocity analysis in a single-channel seismic survey in the Joetsu Basin." GEOPHYSICS 85, no. 2 (February 12, 2020): U47—U53. http://dx.doi.org/10.1190/geo2019-0011.1.

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Historically, marine research has been using single-channel seismic (SCS) devices for scientific projects. Despite SCS’s abundant data availability and the contribution it has brought for subsurface comprehension, few efforts have been dedicated to improve the SCS processing flow to extract more information carried by seismic signals and for better imaging. Diffractions present the necessary means to estimate sediment acoustic properties useful for imaging, stability studies, and geohazard prevention. The root-mean-square (rms) velocity is estimated from diffractions using a diffraction velocity analysis workflow composed of the following main steps: separation of diffractions from specular events using stationary phase properties and plane-wave destruction filtering, determination of diffractor locations in time, velocity scanning using constant rms velocity time migration, automatic picking of rms velocity at the diffractor location in the scan volume, and quality control to avoid spurious rms velocity. The method circumvents the sparsity and nonuniform distribution of diffractions for smooth lateral velocity change conditions. Application in a SCS line acquired in the Joetsu Basin, Japan Sea, indicates improvement in the focusing of deeper events compared to the previous processing flow, and it adds consistent information about the acoustic properties of the subsurface.

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Jian-Fei, Ji, Liang Guo-Long, Pang Fu-Bin, and Zhang Guang-Pu. "Effect Comparative and Experimental Analysis of Diffraction Sound Field Caused by Impedance Sphere and Elastic Spherical Shell on Directivity of Vector Sensor." Noise & Vibration Worldwide 42, no. 11 (December 2011): 57–64. http://dx.doi.org/10.1260/0957-4565.42.11.57.

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The directivity of acoustic vector sensor (AVS) will be distorted by the sound diffraction of the AVS carrier. A common AVS carrier in accordance with its acoustic characteristics can be approximately classified into three types: absolute soft air cavity, absolute rigid solid metal body and elastic shell filled with air. The focus of this paper is placed on the pressure and vibration velocity component of diffraction acoustic field caused by impedance boundary and elastic spherical boundary. Their mathematical expressions are deduced, and their directivity is also analyzed at different frequencies for different impedances. The results show that: for impedance boundary, its influences on directivity of pressure and vibration velocity is decided by the diffraction background term, and for the elastic shell boundary filled with air, the diffraction acoustic field can be seen as the sum of the diffraction acoustic field of rigid boundary and the radiated sound field of elastic vibration spherical shell boundary. When the frequency of the incident plane wave deviates from the resonance frequency of the elastic vibration shell, the diffraction acoustic field of the rigid boundary plays a major role, but when the frequency of the incident plane wave is close to the resonance frequency, the radiated sound field of the elastic vibration shell will hold the dominance. The experimental data are treated and the errors between the experimental results and the theoretical results are analyzed.

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Mantsevich, Sergey, and Ekaterina Kostyleva. "Shear acoustic wave attenuation influence on acousto-optic diffraction in tellurium dioxide crystal." Applied Optics 59, no. 22 (July 30, 2020): 6796. http://dx.doi.org/10.1364/ao.399409.

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31

Huthwaite, P. "Evaluation of inversion approaches for guided wave thickness mapping." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 470, no. 2166 (June 8, 2014): 20140063. http://dx.doi.org/10.1098/rspa.2014.0063.

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Accurate inversion is vital for quantitative imaging, including ultrasonic guided wave tomography, where thickness maps of plate-like structures are reconstructed to quantify corrosion damage. The dispersive properties of guided waves are often exploited to enable thickness maps to be produced from wave speed reconstructions. Ray tomography, diffraction tomography and a hybrid algorithm combining their features were investigated to reconstruct wave speed. Test data produced from simple defects of different sizes using a realistic full elastic guided wave model and the equivalent idealized acoustic model were passed to the imaging algorithms, generating wave speed maps, and, from these, thickness maps. For both datasets, ray tomography exhibited poor resolution. Diffraction tomography performed better, but was limited to shallow, small defects. The hybrid algorithm achieved the best results, giving a resolution around 1.5–2 wavelengths from the realistic test data compared to half wavelength from the idealized case. These results were validated with experimental data, and also extended to a realistic corrosion patch confirming the trends demonstrated with simple defects. The resolution loss with realistic data compared with idealized data indicates the acoustic model cannot accurately capture guided wave scattering and an alternative approach is necessary for better resolution reconstructions.

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Gužas, Danielius, R. Klimas, and V. Tričys. "Influence of Rigidity of Acoustic Shield Walls on Sound Insulation." Solid State Phenomena 113 (June 2006): 252–58. http://dx.doi.org/10.4028/www.scientific.net/ssp.113.252.

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Available shields are of a certain thickness that has an influence on sound diffraction. Judging by the research results, the influence of shield thickness is insignificant if the thickness is less than the length of a sound wave. A thick shield plate or a wide shield has two edges, and this increases noise reduction at the expense of double diffraction. Solution of flat monochromatic wave diffraction has been analyzed. The compact formula of sound insulation at uniform field in front of the shield has been obtained.

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Podlipenko, Yuriy K., Oleg L. Levoshych, and I. I. Popkov. "On Minimax Estimation in the Problems of Acoustic Wave Diffraction." Journal of Automation and Information Sciences 31, no. 1-3 (1999): 22–28. http://dx.doi.org/10.1615/jautomatinfscien.v31.i1-3.230.

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TERAMOTO, Kenbu, Masataka KOHSAKA, MD Tawhidul Islam KHAN, and Akito UEKIHARA. "Gradient Measurement of Acoustic Wave Field with Fraun hofer Diffraction." Transactions of the Society of Instrument and Control Engineers 43, no. 10 (2007): 847–54. http://dx.doi.org/10.9746/ve.sicetr1965.43.847.

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Naumenko, Natalya F., Sergey I. Chizhikov, Vladimir Ya Molchanov, and Konstantin B. Yushkov. "Anisotropic diffraction of bulk acoustic wave beams in lithium niobate." Ultrasonics 63 (December 2015): 126–29. http://dx.doi.org/10.1016/j.ultras.2015.06.019.

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36

Hongo, Kohei, and Hideyoshi Sugaya. "Diffraction of an acoustic plane wave by a rectangular plate." Journal of Applied Physics 82, no. 6 (September 15, 1997): 2719–29. http://dx.doi.org/10.1063/1.366266.

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37

Huang, L. C., C. I. Huang, and A. T. Chwang. "Application of direct integral‐equation method in acoustic‐wave diffraction." Journal of the Acoustical Society of America 89, no. 4B (April 1991): 1973. http://dx.doi.org/10.1121/1.2029733.

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38

Sauer, W., T. H. Metzger, J. Peisl, Y. Avrahami, and E. Zolotoyabko. "Grazing-incidence diffraction on LiNbO3 under surface acoustic wave excitation." Il Nuovo Cimento D 19, no. 2-4 (February 1997): 455–63. http://dx.doi.org/10.1007/bf03041005.

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39

Hahne, G. E. "Transition operators in acoustic-wave diffraction theory. I. General theory." Physical Review A 43, no. 2 (January 1, 1991): 976–89. http://dx.doi.org/10.1103/physreva.43.976.

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40

Danicki, Eugene J. "Surface acoustic wave diffraction in spectral theory of interdigital transducers." Journal of the Acoustical Society of America 114, no. 2 (August 2003): 813–20. http://dx.doi.org/10.1121/1.1579010.

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41

Tret'yakov, P. V. "The diffraction of an arbitrary acoustic wave by a block." Journal of Applied Mathematics and Mechanics 58, no. 3 (January 1994): 559–62. http://dx.doi.org/10.1016/0021-8928(94)90106-6.

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42

Kuzovova, Angela, and Timur Muksunov. "Modeling of Acoustic Processes in Solids Based on Particle Interaction." MATEC Web of Conferences 155 (2018): 01044. http://dx.doi.org/10.1051/matecconf/201815501044.

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An algorithm for the numerical propagation of acoustic waves in solids has been developed. The algorithm is based on the particles interaction model of in a tetrahedral crystal lattice. Numerical integration of Newton's equations in the calculation of particle trajectories is applied. The possibility of numerical modeling of wave diffraction processes on heterogeneities is shown. The resonant phenomena are observed in simulation of acoustic oscillations for an ultrasonic waveguide by means of proposed algorithm.

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43

Rimeika, Romualdas, Paulius Každailis, Daumantas Čiplys, and Saulius Balakauskas. "Control of light polarization by acousto-optic diffraction from leaky acoustic wave in LiNbO_3." Optics Letters 36, no. 13 (July 1, 2011): 2581. http://dx.doi.org/10.1364/ol.36.002581.

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Raitman, E., V. Gavrilov, M. Brezgunov, and D. Mjasiscev. "Neutron Bragg Diffraction on a Bent Silicon Single Crystal Excited by Ultrasound." Latvian Journal of Physics and Technical Sciences 45, no. 2 (January 1, 2008): 52–60. http://dx.doi.org/10.2478/v10047-008-0008-4.

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Neutron Bragg Diffraction on a Bent Silicon Single Crystal Excited by UltrasoundThe neutron Bragg diffraction on a bent silicon monocrystal excited by ultrasound was investigated. It is shown that for perfect crystal the relative diffraction intensity is proportional to the acoustic wave amplitudew.The calibration parameters between the generator voltage and acoustic wave amplitude were derived assumingw= (2.3±0.3)·10-2Å/V. To explain the results, a modified Penning—Polder—Kato model was applied. In a bent crystal, owing to ultrasound, transitions between the sheets of a dispersion surface take place. This leads to various manifestations of the behaviour of the integral scattering intensity, which drastically differs from the case of a perfect crystal. The observed effects may be used for creating new types of neutron monochromators and choppers governed by the ultrasound wave amplitude as well as by the length and bending radius of the crystal.

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Morgan, David P. "A HISTORY OF SURFACE ACOUSTIC WAVE DEVICES." International Journal of High Speed Electronics and Systems 10, no. 03 (September 2000): 553–602. http://dx.doi.org/10.1142/s0129156400000593.

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This paper gives a historical account of the development of Rayleigh-wave, or surface-acoustic-wave (SAW), devices for applications in electronics. The subject was spurred on initially by the requirements of pulse compression radar, and became a practical reality with the planar interdigital transducer, dating from 1965. The accessibility of the propagation path gave rise to substantial versatility, and a huge variety of devices were developed. Passive SAW devices are now ubiquitous, with applications ranging from professional radar and communications systems to consumer areas such as TV, pagers and mobile phones. The paper describes the extensive work, particularly in the 1970s, to investigate SAW propagation in crystalline media, including piezoelectric coupling, diffraction and temperature effects. This led to identification of many suitable materials. Concurrently, many devices began development, including pulse compression filters, bandpass filters, resonators, oscillators, convolvers and matched filters for spread spectrum communications. In the 1970s, many of these became established in professional systems, and the SAW bandpass filter became a standard component for domestic TV. In the 1980s and 90s, SAW responded to the new call for low-loss filters, particularly for mobile phones. With losses as low as 2 dB required (and subsequently achieved) at RF frequencies around 900 MHz, a raft of new technologies was developed. Additionaly, for IF filters special techniques were evolved to reduce the physical size needed for narrow bandwidths. Such devices are now manufactured in very large quantities. In order to satisfy these needs, new types of surface wave, particularly transverse leaky waves, were investigated, and materials using such waves now have their place alongside more traditional materials.

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Richards, S. K., X. X. Chen, X. Huang, and X. Zhang. "Computation of Fan Noise Radiation through an Engine Exhaust Geometry with Flow." International Journal of Aeroacoustics 6, no. 3 (September 2007): 223–41. http://dx.doi.org/10.1260/147547207782419534.

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This paper outlines a computational model of noise radiation from a realistic engine exhaust geometry with flow. The computational model described allows acoustic waves, propagating inside the bypass duct of a generic aircraft engine, to be admitted into a computational domain that includes the aft duct section, the exit plane of the duct, and the jet flow immediately downstream. The method has three parts: a matching process to admit acoustic waves into the induct propagation region; near field propagation inside the duct and diffraction at the lip of the exhaust duct; and an integral surface for far field directivity. In this model the near field propagation is determined by a numerical solution of a 2.5D form of the linearised Euler equations. The mean flow about which the equations are linearised is assumed to be axisymmetric. The proposed method is illustrated through a case study on the radiation of a typical fan assembly generated acoustic wave from a generic engine bypass duct. Inside the duct, an acoustic wave of circumferential order m = −13 and comprising five radial modes ( n = 1 – 5) is admitted into the model as inputs on the boundary of the computation domain. The radiation of the acoustic wave through the exhaust geometry and mean flow is determined, with the effect of acoustic treatment through the inclusion of lined duct sections also examined.

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Ayub, M., M. H. Tiwana, A. B. Mann, and H. Zaman. "Acoustic Wave Propagation in a Trifurcated Lined Waveguide." ISRN Applied Mathematics 2011 (June 20, 2011): 1–19. http://dx.doi.org/10.5402/2011/532682.

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The diffraction of sound from a semi-infinite soft duct is investigated. The soft duct is symmetrically located inside an acoustically lined but infinite duct. A closed-form solution is obtained using integral transform and Jones' method based on Wiener-Hopf technique. The graphical results are presented, which show how effectively the unwanted noise can be reduced by proper selection of different parameters. The kernel functions are factorized with different approaches. The results may be used to design acoustic barriers and noise reduction devices.

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WANG, JUNTAO, QUN HAN, JIPING NING, and YANG HE. "SURFACE-ACOUSTIC-WAVE FIELD AND ACOUSTO-OPTIC INTERACTION IN AlN/128-DEG-ROTATED Y-CUT X-PROPAGATION LiNbO3." Modern Physics Letters B 27, no. 05 (February 5, 2013): 1350032. http://dx.doi.org/10.1142/s0217984913500322.

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The efficiency of guided-wave acousto-optic (AO) interaction in AlN /128-deg-rotated Y-cut X-propagation lithium niobate (128-deg YX- LiNbO 3) structure is analyzed theoretically for the first time by determining the overlap integral between the optical and the surface acoustic wave (SAW) field distribution. The results show that the use of an AlN film can increase the phase velocity of SAW, the electromechanical coupling coefficient and the diffraction efficiency of AO interaction. A maximum of 9.33% for the electromechanical coupling coefficient is obtained when the normalized thickness of AlN film equals 0.09. The diffraction efficiency has a significant improvement when the normalized thickness of AlN film is increased from 0 to 0.05. And, the improvement for the TM polarization is more evident than that for the TE polarization. However, for a well-concentrated optical waveguide, the use of an AlN film reduces the diffraction efficiency of the TM polarization when the SAW frequency is low.

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Punegov, Vasily I. "The dynamical theory of diffraction in a crystal modulated by a surface acoustic wave in the case of spatially restricted X-ray beams." Journal of Applied Crystallography 52, no. 6 (October 22, 2019): 1289–98. http://dx.doi.org/10.1107/s1600576719012603.

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The dynamical theory of X-ray diffraction in a crystal modulated by a surface acoustic wave (SAW) is developed for spatially restricted beams. It is shown that this approach is applicable to X-ray reciprocal space mapping. Rayleigh's surface-wave model is used to describe ultrasonic excitation. Based on the recurrent relations, a numerical simulation of the dynamical diffraction in a crystal modulated by a SAW is performed. Within the framework of the triple-axis diffraction scheme, the effect of the instrumental function on X-ray diffraction data is studied.

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Реут, О. В. "Diffraction of wave on the conical defect in the acoustic environment." Researches in Mathematics and Mechanics 23, no. 1(31) (June 1, 2018): 88–94. http://dx.doi.org/10.18524/2519-206x.2018.1(31).134621.

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Journal articles on the topic 'Acoustic wave diffraction'

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