M. Planat, G. Vanderborck, H. Gautier, C. Maerfeld
Absfmct-A variational finite element analyijs of linear and low nonlinear guided wave propagation in piezoelectric media is proposed here. The method is applied to thin metallic AI &ides on Ez LiNb03! such as employed in waveguide convolvers. First dispersion c‘urves and tield amplitude profiles for linear analysis are obtained. Then the method is applied to account for the nonlinear mixing mechanisps and to compute the,ponvolution 6gure of merit. The hear field distribution at w is used to compute the driving forces at 2w, and the forced problem is solved at 2w.
{"title":"A Finite Element Analysis of the Piezoelectric Waveguide Convolver","authors":"M. Planat, G. Vanderborck, H. Gautier, C. Maerfeld","doi":"10.1109/T-SU.1985.31612","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31612","url":null,"abstract":"Absfmct-A variational finite element analyijs of linear and low nonlinear guided wave propagation in piezoelectric media is proposed here. The method is applied to thin metallic AI &ides on Ez LiNb03! such as employed in waveguide convolvers. First dispersion c‘urves and tield amplitude profiles for linear analysis are obtained. Then the method is applied to account for the nonlinear mixing mechanisps and to compute the,ponvolution 6gure of merit. The hear field distribution at w is used to compute the driving forces at 2w, and the forced problem is solved at 2w.","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120959033","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}
Selection de materiaux utilises dans les transducteurs d'ultrasons et les systemes de mesure ultrasonore. Cette selection peut etre effectuee sur la base des proprietes telles que vitesse acoustique, impedance et attenuation mais egalement sur la propriete d'adherence a l'epoxyde, la linearite et la propriete d'absorption de l'eau. Table des materiaux qui ont ete mesures ou dont les proprietes ont ete obtenues a partir de references
{"title":"Approximate Material Properties in Isotropic Materials","authors":"A. R. Selfridge","doi":"10.1109/T-SU.1985.31608","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31608","url":null,"abstract":"Selection de materiaux utilises dans les transducteurs d'ultrasons et les systemes de mesure ultrasonore. Cette selection peut etre effectuee sur la base des proprietes telles que vitesse acoustique, impedance et attenuation mais egalement sur la propriete d'adherence a l'epoxyde, la linearite et la propriete d'absorption de l'eau. Table des materiaux qui ont ete mesures ou dont les proprietes ont ete obtenues a partir de references","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128200729","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}
Abstmct-Line acoustic waves (LAW), guided acoustic modes which follow a sharp edge of a substrate, are of interest for convolver applications because their tight energy confinement produces high strains. A segmented multistrip coupler, or multistrip mode converter (MSMC), is described that converts SAW energy to LAW energy. The segmentation serves several purposes. If the LAW velocity is not precisely known, the MSMC can compensate somewhat for incorrect choice of grafting pitches in the SAW and LAW tracks. The segmentation also allows the structure to take less space on the substrate. A coupled-rnode analysis of the MSMC and results on an experimental four-segment MSMC operating at 100 MHz with 25 percent bandwidth are presented. Although the MSMC should he capable of nearly complete energy transfer, this particular design was shorter than a full transfer length and had a conversion loss of about 5 dB. The predicted value of 4.9-dB conversion loss is in good agreement with experiment.
{"title":"Broadband Generation of Line Acoustic Waves","authors":"R.L. Miller, G. Pieters, B. J. Hunsinger","doi":"10.1109/T-SU.1985.31613","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31613","url":null,"abstract":"Abstmct-Line acoustic waves (LAW), guided acoustic modes which follow a sharp edge of a substrate, are of interest for convolver applications because their tight energy confinement produces high strains. A segmented multistrip coupler, or multistrip mode converter (MSMC), is described that converts SAW energy to LAW energy. The segmentation serves several purposes. If the LAW velocity is not precisely known, the MSMC can compensate somewhat for incorrect choice of grafting pitches in the SAW and LAW tracks. The segmentation also allows the structure to take less space on the substrate. A coupled-rnode analysis of the MSMC and results on an experimental four-segment MSMC operating at 100 MHz with 25 percent bandwidth are presented. Although the MSMC should he capable of nearly complete energy transfer, this particular design was shorter than a full transfer length and had a conversion loss of about 5 dB. The predicted value of 4.9-dB conversion loss is in good agreement with experiment.","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122562439","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}
The diagnostic utility of quantitative backscatter imaging (B'-scan) was investigated using three groups of patients. Estimates of both the attenuation coefficient and the backscatter coefficient in the first group of healthy volunteers were consistent with results reported elsewhere. The backscatter coefficient measured in a group of six sub- jects with documented cirrhosis of the liver was significantly higher than normal. In contrast, the backscatter coefficient measured in a group of six subjects with adenocarcinoma metastasis of the liver was significantly lower than normal. These results suggest that the B'-Scan augments the information of a conventional B-scan.
{"title":"Clinical Evaluation of the B'-Scan","authors":"Matthew O’DONNELL, Herbert F. Reilly","doi":"10.1109/T-SU.1985.31614","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31614","url":null,"abstract":"The diagnostic utility of quantitative backscatter imaging (B'-scan) was investigated using three groups of patients. Estimates of both the attenuation coefficient and the backscatter coefficient in the first group of healthy volunteers were consistent with results reported elsewhere. The backscatter coefficient measured in a group of six sub- jects with documented cirrhosis of the liver was significantly higher than normal. In contrast, the backscatter coefficient measured in a group of six subjects with adenocarcinoma metastasis of the liver was significantly lower than normal. These results suggest that the B'-Scan augments the information of a conventional B-scan.","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128111873","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}
Abstmet-The attenuation coefficient in livers of 16 normal patients was estimated using a modified real-time sector scanner at 3 MHz and a narrow-band estimation technique. It was found that the estimates contained a range-dependent bias term, and that the variance of the estimate was positively correlated with the second spatial derivative of the beam-sensitivity profile beyond the focus of the transducer. We have postulated a stochastic model that demonstrates a relationship between the variance of the estimate and the product of the variance of the abdominal wall thickness fluctuations and the second derivative of the axial beam sensitivity profile. The consequences and limitations of this model are discussed.
{"title":"Range-Dependent Variance Artifacts in Narrow-Band Estimates of In Vivo Liver Attenuation","authors":"J. Ophir, N. Maklad","doi":"10.1109/T-SU.1985.31616","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31616","url":null,"abstract":"Abstmet-The attenuation coefficient in livers of 16 normal patients was estimated using a modified real-time sector scanner at 3 MHz and a narrow-band estimation technique. It was found that the estimates contained a range-dependent bias term, and that the variance of the estimate was positively correlated with the second spatial derivative of the beam-sensitivity profile beyond the focus of the transducer. We have postulated a stochastic model that demonstrates a relationship between the variance of the estimate and the product of the variance of the abdominal wall thickness fluctuations and the second derivative of the axial beam sensitivity profile. The consequences and limitations of this model are discussed.","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"119 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124158561","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}
A new blood Row imaging system is described that com- bines a conventional pulsed Doppler device and a newly developed au- tocorrelator. In the system blood flow within a given cross section of a live organ is displayed in real time. The direction of blood Row and its variance are expressed by means of a difference in color and its hue, respectively. Experiments were conducted with a mechanical and an electrical scanner using phantoms, and good agreement with the theory was obtained. Studies on clinical significance have also been carried out for normal and diseased hearts, and successful results have been found.
{"title":"Real-Time Two-Dimensional Blood Flow Imaging Using an Autocorrelation Technique","authors":"C. Kasai, K. Namekawa, Akira Koyano, Ryozo Omoto","doi":"10.1109/T-SU.1985.31615","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31615","url":null,"abstract":"A new blood Row imaging system is described that com- bines a conventional pulsed Doppler device and a newly developed au- tocorrelator. In the system blood flow within a given cross section of a live organ is displayed in real time. The direction of blood Row and its variance are expressed by means of a difference in color and its hue, respectively. Experiments were conducted with a mechanical and an electrical scanner using phantoms, and good agreement with the theory was obtained. Studies on clinical significance have also been carried out for normal and diseased hearts, and successful results have been found.","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114810170","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}
Reflexion d'ondes acoustiques de surface et changements de vitesse causes par des reseaux de rubans metalliques court-circuites
表面声波的反射和由短路金属带网络引起的速度变化
{"title":"Analysis of Metal-Strip SAW Gratings and Transducers","authors":"Dong-Pei Chen, H. Haus","doi":"10.1109/T-SU.1985.31609","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31609","url":null,"abstract":"Reflexion d'ondes acoustiques de surface et changements de vitesse causes par des reseaux de rubans metalliques court-circuites","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133937729","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}
Abstmct-Experimental and theoretical studies have revealed several effects in surface-acoustic-wave chirp filters that arise from electrode reflections. One effect is that down-chirp filters have lower loss than up-chirp filters, which is shown to be caused by asymmetric phasing of reflections by near-synchronous electrodes. The most prominent effect is large amplitude ripple in the passband of broadband down-chirp mters, occurring at frequencies above the second harmonic of the synchronous frequency of the lowest-frequency electrodes, and caused by surface wave reflections by electrodes with a synchronous frequency that is half the operating frequency. The large amplitude ripple is halved in nondispersive chirp filters and does not occur in up-chirp filters. A further effect is enhanced triple-transit ripple, which is also due to “second harmonic” reflections, and occurs in both upand down-chirp filters. A design procedure that suppresses the large amplitude ripple is described and is found experimentally to be effective. Relations are given for the estimation of directionality, and single and triple transit ripple amplitudes due to second harmonic reflections, for chirp filters with arbitrary chirp law, bandwidth, and dispersion time.
{"title":"Electrode Reflections, Directionality, and Passband Ripple in Wideband SAW Chirp Filters","authors":"B. Lewis, R. G. Arnold","doi":"10.1109/T-SU.1985.31610","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31610","url":null,"abstract":"Abstmct-Experimental and theoretical studies have revealed several effects in surface-acoustic-wave chirp filters that arise from electrode reflections. One effect is that down-chirp filters have lower loss than up-chirp filters, which is shown to be caused by asymmetric phasing of reflections by near-synchronous electrodes. The most prominent effect is large amplitude ripple in the passband of broadband down-chirp mters, occurring at frequencies above the second harmonic of the synchronous frequency of the lowest-frequency electrodes, and caused by surface wave reflections by electrodes with a synchronous frequency that is half the operating frequency. The large amplitude ripple is halved in nondispersive chirp filters and does not occur in up-chirp filters. A further effect is enhanced triple-transit ripple, which is also due to “second harmonic” reflections, and occurs in both upand down-chirp filters. A design procedure that suppresses the large amplitude ripple is described and is found experimentally to be effective. Relations are given for the estimation of directionality, and single and triple transit ripple amplitudes due to second harmonic reflections, for chirp filters with arbitrary chirp law, bandwidth, and dispersion time.","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117049878","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}
Abslmcf-A methodology for complete characterization of thinand thick-film materials deposited on a substrate using widehand reflection acoustic microscopy is presented. A wideband reflection acoustic microscope that covers the frequency range of 50 to 175 MHz was constructed to carry out the experimental verification. The amplitude of the reflection coefficient of the film-substrate composite was measured versus the acoustic frequency to identify the resonant frequency of the specimen at which the film thickness is equal to one quarter of the acoustic wavelength. Then both the amplitude and the phase of the reflection coefficient at the resonant frequency were measured. Using the three measured quantities, thickness, acoustic velocity, and mass density of the film material are simultaneously determined without any prior knowledge. Two types of film materials, namely Pyrex glass film sputtered on a sapphire substrate and positive photoresist coated on a Pyrex glass substrate have been characterized using the methodology. The three measured acoustic parameters, film thickness, acoustic velocity, and mass density, agree well with the published values. For the frequency range of the microscope utilized the corresponding range of measurable film thickness is 30 pm to 5 pm for most inorganic materials, and 10 pm to 2 pm for most organic materials. For the case in which the film thickness is less than one quarter of the acoustic wavelength at the highest operation frequency of the microscope, the resonant frequency cannot be identified. However. one or two of the three acoustic parameters can still be determined by measuring the amplitude and the phase of the reflection coefficient a t a fixed acoustic frequency. This capability has been demonstrated using a gold fdm deposited on fused quartz and an aluminum film evaporated on X-cut LiNbOj substrate. Three additional transducer/lens sets with staggered center frequencies are also being assembled to cover the entire frequency range from 175 MHz t o 1000 MHz so that the measurable range of the film thickness can be extended to the submicron region. Consequently, it is concluded that this characterization methodology should he highly useful For nondestructive study of thinand thick-film materials in microelectronics.
{"title":"Complete Characterization of Thin- And Thick-Film Materials Using Wideband Reflection Acoustic Microscopy","authors":"C. Lee, C. Tsai, Xin Cheng","doi":"10.1109/T-SU.1985.31591","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31591","url":null,"abstract":"Abslmcf-A methodology for complete characterization of thinand thick-film materials deposited on a substrate using widehand reflection acoustic microscopy is presented. A wideband reflection acoustic microscope that covers the frequency range of 50 to 175 MHz was constructed to carry out the experimental verification. The amplitude of the reflection coefficient of the film-substrate composite was measured versus the acoustic frequency to identify the resonant frequency of the specimen at which the film thickness is equal to one quarter of the acoustic wavelength. Then both the amplitude and the phase of the reflection coefficient at the resonant frequency were measured. Using the three measured quantities, thickness, acoustic velocity, and mass density of the film material are simultaneously determined without any prior knowledge. Two types of film materials, namely Pyrex glass film sputtered on a sapphire substrate and positive photoresist coated on a Pyrex glass substrate have been characterized using the methodology. The three measured acoustic parameters, film thickness, acoustic velocity, and mass density, agree well with the published values. For the frequency range of the microscope utilized the corresponding range of measurable film thickness is 30 pm to 5 pm for most inorganic materials, and 10 pm to 2 pm for most organic materials. For the case in which the film thickness is less than one quarter of the acoustic wavelength at the highest operation frequency of the microscope, the resonant frequency cannot be identified. However. one or two of the three acoustic parameters can still be determined by measuring the amplitude and the phase of the reflection coefficient a t a fixed acoustic frequency. This capability has been demonstrated using a gold fdm deposited on fused quartz and an aluminum film evaporated on X-cut LiNbOj substrate. Three additional transducer/lens sets with staggered center frequencies are also being assembled to cover the entire frequency range from 175 MHz t o 1000 MHz so that the measurable range of the film thickness can be extended to the submicron region. Consequently, it is concluded that this characterization methodology should he highly useful For nondestructive study of thinand thick-film materials in microelectronics.","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121790791","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 Microscopy Commentary: SLAM and SAM","authors":"L. W. Kessler","doi":"10.1109/T-SU.1985.31580","DOIUrl":"https://doi.org/10.1109/T-SU.1985.31580","url":null,"abstract":"","PeriodicalId":371797,"journal":{"name":"IEEE Transactions on Sonics and Ultrasonics","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129585936","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}
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