IEEE 1987 Ultrasonics Symposium最新文献

{"title":"Acoustic Modes in Lithium Tetraborate","authors":"W. S. Lshak, C. Flory, B. Auld","doi":"10.1109/ULTSYM.1987.198962","DOIUrl":"https://doi.org/10.1109/ULTSYM.1987.198962","url":null,"abstract":"Acoustic modes propagating in X-cut. Z-propagating lithium tetraborate (Li2B407) substrates have been analyzed theoretically and experimentally. The theoretical predictions were made using a computer program written to search for all possible acoustic modes propagating in arbitrary cuts of piezoelectric materials. A new photolithographic process has been developed to fabricate interdigital transducers (IDTs) on Li2B407 to avoid using acids which attack and damage the substrates. Using this process, split-electrode SAWIDTs were fabricated with a period of 16 pm. The frequencies of the observed modes agreed to better than 0.5% with the theoretical predictions. The insertion loss of the SAW delay line was less than 10 dB at 219 MHz and the temperature coefkient of delay was measured to be about 6 ppm/\"C. These numbers suggest that Li2B407 is a candidate to replace quartz as a substrate for narrowband SAW filter applications. A detailed description of the properties of the observed modes will be given. Methods used to suppress the non-SAW modes will also be described.","PeriodicalId":309261,"journal":{"name":"IEEE 1987 Ultrasonics Symposium","volume":"1115 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129213716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electromechanical Coupling to Lamb and SH Modes in Piezoelectric Plates","authors":"E. Adler","doi":"10.1109/ULTSYM.1987.198966","DOIUrl":"https://doi.org/10.1109/ULTSYM.1987.198966","url":null,"abstract":"Recent theoretical studies arid experiments have shown that interdigital transducers (IDTs) can couple strongly to plate modes in piezoelectric materials and in piezoelectric-on-nonpiezoelectic composite membranes. It has been demonstrated that silicon can support zinc oxide films to form thin composite membranes with large electromechanical coupling factors, a technology which allows integration of plate mode devices with ICs. In this paper the calculated velocity dispersion and electromechanical coupling factors for plate modes in representative piezoelectric materials are described. The frequency dependence of velocity and electromechanical coupling factors are given, under different metallization conditions, for: generalized stiffened-Lamb, pure stiffenedLamb, and stiffened- shear (SH) modes, for various plate orientations in lithium niobate, lithium tantalate, quartz, bismuth germanium oxide and zinc oxide. For lithium niobate electromechanical coupling (AVIV) values as high as 15% are found under narrow-band band-pass conditions arid 5% under wide-band low-pass conditions. For lithium tantalate, bismuth germanium oxide, and zinc oxide, coupling values of 0.5%, 2%, and 4% are obtained. For quartz, with its weaker piezoelectricity, the coupling is still smaller. Details of the frequency dependence of coupling factors, wave velocities, and electric and mechanical field profiles which characterize the various mode types are presented.","PeriodicalId":309261,"journal":{"name":"IEEE 1987 Ultrasonics Symposium","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123937356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gasflow and Energy Measurement Using Coherently Modulated Ultrasound","authors":"R. Redding","doi":"10.1109/ULTSYM.1987.199032","DOIUrl":"https://doi.org/10.1109/ULTSYM.1987.199032","url":null,"abstract":"","PeriodicalId":309261,"journal":{"name":"IEEE 1987 Ultrasonics Symposium","volume":"47 37","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120889024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Double Frequency Doppler Technique for Bubble Size Measurement","authors":"J. Chapelon, D. Cathignol, V. Newhouse, P. Shankar","doi":"10.1109/ULTSYM.1987.199086","DOIUrl":"https://doi.org/10.1109/ULTSYM.1987.199086","url":null,"abstract":"The Double Frequency technique of bubble sizina has been shown to be an excelient technique-for the detction ana sizing of microbubbles in fluids. In this technique the bubbles are insonified by two sound fields, a high frequency imaging field and low frequency pumping field. The sum and difference frequency signals generated from the oscillations of the pumped bubbles are used for size measurements. However this technique does lead to some problems from similar signals generated by stationary targets. One way of overcoming this problem is to use the Doppler signals generated by the moving bubbles. In this paper we propose a new technique based on the amplitude measurement of the Doppler spectra generated by the motion of the bubble and the sidebands produced from the Double Frequency technique. Experimental results indicate that size measurements obtained through this method agree with size measuments using Stoke's law. Bubbles are excellent scatters of sound. They can be detected easily by classical ultrasonic imaging systems such as a real time ultrasonic B scan or a Doppler flowmeter ( 1,2,3). Although these techniques have been proposed (for example (3)) to size the bubbles they do not provide accurate size estimates, mainly because there is no way of separating the echoes from bubbles of different size, in other words a group of small bubbles can give rise to the same echo a large bubble. As bubbles exibit a resonant behavior, they have a characteristic frequency inversely proportional to their size. These size dependent oscillations have been already exploited trough different methods including resonant scattering(3), second harmonic generation(4) and double frequency technique(S). Even though the Double Frequency technique where a low frequency pumping field and a high frequency imaging field are used, has better spatial resolution and excellent size descrimination, the presence of stationnary targets may sometimes give rise to signals similar to those of resonating bubbles. Thus any size measurement based on the Double Frequency technique also may lead to erroneous sizes unless steps are made to take these motion dependent changes into account and a suitable sytem designed accordingly. In this paper we propose a new technique based on the amplitude measurement of the Doppler spectra generated by the motion of the bubble and the sidebands produced from the Double Frequency technique. In the first section, we illustrate the principle of the Double Frequency Doppler technique by explaining the formation of the Doppler spectra sidelobes as the bubble goes through its resonanance when excited by a pumping field and an imaging field. The processing of these signals through each stage of the block diagram is discused to explain the extraction of the bubble resonance. Then, with the","PeriodicalId":309261,"journal":{"name":"IEEE 1987 Ultrasonics Symposium","volume":"18 3-4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114110452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dispersion Control of Magnetostatic Waves Using Layered Structure","authors":"N. B. Chakrabarti, T. Rao, T. V. Rao, B. Roy, D. Bhattacharya","doi":"10.1109/ULTSYM.1987.198959","DOIUrl":"https://doi.org/10.1109/ULTSYM.1987.198959","url":null,"abstract":"The dispersion relation of the magnetostatic surface wave propsgating in a ferrimagnetic double layer h as been found and the effects of v arious layers on the propagation characteristics have been examined. A linear delay variation extending from 125 ns/cm to 365 ns/cm over an 0.4 GHz bandwidth centered at 2.8 GHz is obtainable with YIG films of 10 micron thicknesses b ut with 4nM values as 1.75KG and 1.QKC respectfvely. havior of the magnetostatic surface wave propagation w ith in-plane magnetic field applied at an angle normal to the direction of propagation, has been studied and time delays have been computed as a function of this angle. Under this condition t he backward volume wzves are also generated along with surface waves\"he be","PeriodicalId":309261,"journal":{"name":"IEEE 1987 Ultrasonics Symposium","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114634751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New SAW Velocity Measurements on Y-Cut LiNbO3","authors":"M. Anhorn, H. Engan, A. Rønnekleiv","doi":"10.1109/ULTSYM.1987.198969","DOIUrl":"https://doi.org/10.1109/ULTSYM.1987.198969","url":null,"abstract":"Recent measiirements on SAW velocities are reported. The results are based on scanning of a laser probe across the propagation beam at certain intervals. Previously reported measurements on YZ LiNb03 have been extended to include the complete Y surface. For t.his orientation, results for both a free surface and a metallized surface are reported. A noticeable digference has been found between the beam steering properties of free and met.alized surface around Z propagation direction. Effects from va r i a t ion (I) f me t a 1 1 i z a t i on t h i c kne s s have been studied also and are presented. Many SAW devices use parallel metal strips on the substrate surface. Measurements on the angular variation of SAW velocities in such st.ructiires are reported.","PeriodicalId":309261,"journal":{"name":"IEEE 1987 Ultrasonics Symposium","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127792801","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Is Acoustic Cavitation Produced by Diagnostic Ultrasound Devices?","authors":"L. Crum","doi":"10.1109/ULTSYM.1987.199108","DOIUrl":"https://doi.org/10.1109/ULTSYM.1987.199108","url":null,"abstract":"There is considerable evidence that acoustic c avitation can be produced in vivo by diagnostic ultrasound d evices. T his paper presents the available evidence and concludes that it is likely that acoustic cavitation is produced by these d evices ii w. However, because of the discrete nature of the cavitation, and the limited number of events that occur, this cavitation is unlikely to be detected or to manifest itself in terms of deleterious b iological effects .","PeriodicalId":309261,"journal":{"name":"IEEE 1987 Ultrasonics Symposium","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126265855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A 400MHz One-Chip Oscillator Using an Air-Gap Type Thin Film Resonator","authors":"H. Satoh, H. Suzuki, C. Takahashi, C. Narahara, Y. Ebata","doi":"10.1109/ULTSYM.1987.198984","DOIUrl":"https://doi.org/10.1109/ULTSYM.1987.198984","url":null,"abstract":"A preliminary study has been made on the fabrication technique and on the spurious response of a self-supported airgap type resonator on a SigN4 passivation film covering a Si substrate with the purpose ot bipolar monolithic oscillator application. A prototype 400MHz fully integrated one-chip oscillator consisting of a Colpitts-type circuit and the resonator is developed. The developed miniature oscillator is about lmm square in actual size. A typical performance is; 90dB for C/N (N: 20KHz offset from the carrier and 16KHz band width), 0- -5ppm/ .C for the 1st order temperature coefficient of frequency arid -0.029ppm/OC2 for the 2nd order temperature coefficient.","PeriodicalId":309261,"journal":{"name":"IEEE 1987 Ultrasonics Symposium","volume":"2011 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125626383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Acoustic Fiber Waveguide Coupler","authors":"A. L. Matthews, K. Murphy, R. E. Rogers, R. Claus","doi":"10.1109/ULTSYM.1987.199034","DOIUrl":"https://doi.org/10.1109/ULTSYM.1987.199034","url":null,"abstract":"A fused biconical taper acoustic fiber waveguide couuler for application in acoustic fiber sensing systems has been developed and evaludted. The coupler is fabricated by twisting together two glass-on-glass acoustic fiber waveguides and fusing them using applied heat. Fulling on the fibers minimizes the coupler's taper region. The subsequent pushing together of the fibers forms a glass ball at the center of the coupler region. The heated fibers are then pulled again until the desired acoustic coupling S-parameters are achieved. This new method of acoustic fiber coupler fabrication allows coupler performance evaluation based upon taper symmetry, fiber geometry and measurement tolerance. Fiber coupler operation and measurements cf coupler performance are presented.","PeriodicalId":309261,"journal":{"name":"IEEE 1987 Ultrasonics Symposium","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115774741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Automatic Ultrasonic Image Analysis Method for Defect Detection","authors":"G. Corneloup, B. Cornu, I. Magnin, M. Perdrix","doi":"10.1109/ULTSYM.1987.199119","DOIUrl":"https://doi.org/10.1109/ULTSYM.1987.199119","url":null,"abstract":"Ultrasonic examination of seams raises well known signals perturbed by this austenitic steel weld problems of interpreting type of material. The JUKEBOX ultrasonic imaging system developed at the Cadarache Nuclear Research Center provides a malor improvement in the general area of defect localization and characterization, based on processing overall images obtained by iX,Y) scanning. (X,timel images are formed by ~uxtaposing input signals. A series of parallel images shifted on the Y-axis is also available. The authors present a novel deCect detection method based on analysing the timeline positions of the maxima and minima recorded on (X,time) images. This position is statistically stable when a defect is encoutered, and is random enough under spurious noise conditions to constitute a discriminating parameter. The investigation involves calculating the trace variance: this parameter is then taken into account for detection purposes. Correlation with parallel images enhances detection reliability. A significant increase in the signal-to-noise ratio during tests on artificial defects is shown.","PeriodicalId":309261,"journal":{"name":"IEEE 1987 Ultrasonics Symposium","volume":"102 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115852929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}