Pub Date : 2014-10-23DOI: 10.1109/ULTSYM.2014.0217
S. Biryukov, H. Schmidt, A. Sotnikov, M. Weihnacht, S. Sakharov, O. Buzanov
Recently big size high quality piezoelectric single crystals of Ca3TaGa3Si2O14 (CTGS) have been grown. This temperature durable crystal is very promising for future application in different devices based on surface acoustic waves (SAW) due to its high electromechanical coupling compared to quartz. In contrast to the popular langasite, CTGS is a more ordered compound and therefore stands for better characteristics at both, high temperatures and high frequencies. During the last decade several sets of material constants for CTGS were published extracted from bulk acoustic wave measurements on small samples, but these results are strongly different from each other. Moreover, all published constant sets lead to unacceptable numerical differences for calculated SAW velocities when compared to recent measurements of SAW velocities on large CTGS wafers. In this work we present a new set of room temperature CTGS material constants, extracted by combination of high-precision SAW phase velocity measurements with proprietary numerical procedures developed in-house.
{"title":"CTGS material parameters obtained by versatile SAW measurements","authors":"S. Biryukov, H. Schmidt, A. Sotnikov, M. Weihnacht, S. Sakharov, O. Buzanov","doi":"10.1109/ULTSYM.2014.0217","DOIUrl":"https://doi.org/10.1109/ULTSYM.2014.0217","url":null,"abstract":"Recently big size high quality piezoelectric single crystals of Ca3TaGa3Si2O14 (CTGS) have been grown. This temperature durable crystal is very promising for future application in different devices based on surface acoustic waves (SAW) due to its high electromechanical coupling compared to quartz. In contrast to the popular langasite, CTGS is a more ordered compound and therefore stands for better characteristics at both, high temperatures and high frequencies. During the last decade several sets of material constants for CTGS were published extracted from bulk acoustic wave measurements on small samples, but these results are strongly different from each other. Moreover, all published constant sets lead to unacceptable numerical differences for calculated SAW velocities when compared to recent measurements of SAW velocities on large CTGS wafers. In this work we present a new set of room temperature CTGS material constants, extracted by combination of high-precision SAW phase velocity measurements with proprietary numerical procedures developed in-house.","PeriodicalId":153901,"journal":{"name":"2014 IEEE International Ultrasonics Symposium","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115109021","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}
Pub Date : 2014-10-23DOI: 10.1109/ULTSYM.2014.0105
D. Maresca, M. Tanter, M. Pernot
Rheumatoid arthritis (RA) is a common autoimmune disease associated with chronic inflammation, referred to as synovitis, and ultimately joint destruction. It is acknowledged that ultrasound Power Doppler imaging can reveal subclinical synovitis but the quantification of inflammation stages is currently limited by the coarse resolution and sensitivity of conventional Doppler imaging. Here we show that ultrafast Doppler imaging characterizes metacarophalangeal joint microvasculature with an unprecedented accuracy, making it a promising microangiography method for the early diagnosis of RA. We made use of a 15 MHz probe (256 elements linear array, 0.125 mm pitch) connected to a programmable ultrafast ultrasound scanner. We insonified the second metacarpophalangeal joint of 13 healthy volunteers with a dedicated ultrafast Doppler imaging sequence consisting of 41 plane wave transmissions at a pulse repetition frequency of 20 kHz during one second. The received ultrasound data were beamformed and digitally filtered to get rid of tissue clutter. Power Doppler maps were computed and overlaid on co-registered Bmode images of the joint anatomy. Ultrafast Doppler imaging allowed for the detection of healthy metacarpophalangeal joint microvasculature, which is invisible in conventional Power Doppler imaging. We imaged microvascular blood flow in 12 out of 13 healthy joints, with Doppler signal to noise ratios of the order of 5 dB. In addition, we computed for each individual a functional capillary density (defined as the length of perfused capillaries in mm per tissue area in mm2) and obtained values of the order of 0.6 ± 0.1 mm microvessel/mm2 tissue. The method, which can be readily implemented on ultrafast ultrasound scanners, shows strong potential for the early diagnosis of RA and has the advantage of being fully noninvasive. A group of RA patients with different stages of inflammation will be investigated next.
{"title":"Ultrasound microangiography of the metacarophalangeal joint using ultrafast Doppler","authors":"D. Maresca, M. Tanter, M. Pernot","doi":"10.1109/ULTSYM.2014.0105","DOIUrl":"https://doi.org/10.1109/ULTSYM.2014.0105","url":null,"abstract":"Rheumatoid arthritis (RA) is a common autoimmune disease associated with chronic inflammation, referred to as synovitis, and ultimately joint destruction. It is acknowledged that ultrasound Power Doppler imaging can reveal subclinical synovitis but the quantification of inflammation stages is currently limited by the coarse resolution and sensitivity of conventional Doppler imaging. Here we show that ultrafast Doppler imaging characterizes metacarophalangeal joint microvasculature with an unprecedented accuracy, making it a promising microangiography method for the early diagnosis of RA. We made use of a 15 MHz probe (256 elements linear array, 0.125 mm pitch) connected to a programmable ultrafast ultrasound scanner. We insonified the second metacarpophalangeal joint of 13 healthy volunteers with a dedicated ultrafast Doppler imaging sequence consisting of 41 plane wave transmissions at a pulse repetition frequency of 20 kHz during one second. The received ultrasound data were beamformed and digitally filtered to get rid of tissue clutter. Power Doppler maps were computed and overlaid on co-registered Bmode images of the joint anatomy. Ultrafast Doppler imaging allowed for the detection of healthy metacarpophalangeal joint microvasculature, which is invisible in conventional Power Doppler imaging. We imaged microvascular blood flow in 12 out of 13 healthy joints, with Doppler signal to noise ratios of the order of 5 dB. In addition, we computed for each individual a functional capillary density (defined as the length of perfused capillaries in mm per tissue area in mm2) and obtained values of the order of 0.6 ± 0.1 mm microvessel/mm2 tissue. The method, which can be readily implemented on ultrafast ultrasound scanners, shows strong potential for the early diagnosis of RA and has the advantage of being fully noninvasive. A group of RA patients with different stages of inflammation will be investigated next.","PeriodicalId":153901,"journal":{"name":"2014 IEEE International Ultrasonics Symposium","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115984716","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}
Pub Date : 2014-10-23DOI: 10.1109/ULTSYM.2014.0552
F. Varray, H. Liebgott, C. Cachard, D. Vray
In the medical ultrasound (US) community, only few simulators are able to fully simulate nonlinear wave propagation. In our recently developed software Creanuis [1], realistic nonlinear radio-frequency US images can be simulated. Unfortunately, the rather long computation time represents an important limitation, and is far from being comparable with the fastest simulation tools based on convolution strategies. In this work, a strategy combining Creanuis with a convolution appoach is proposed. This pseudo-acoustic nonlinear image strategy (PANIS) produces linear as well as nonlinear images. It consists to first simulate a set of punctual scatterers to locally extract a nonlinear point-spread function (PSF). Then, the 2D convolution of each of these PSF and the full medium is performed. The final PANIS image is obtained by selecting the specific part of each elementary convolved images. This final image contains the whole spectrum evolution with a depth dependent resolution and signal-to-noise ratio. The root-mean square error, between the statistics of PANIS and Creanuis images is kept under 1% and validates the model. The computation time is kept under 10 secondes for the convolution part.
{"title":"Fast simulation of realistic pseudo-acoustic nonlinear radio-frequency ultrasound images","authors":"F. Varray, H. Liebgott, C. Cachard, D. Vray","doi":"10.1109/ULTSYM.2014.0552","DOIUrl":"https://doi.org/10.1109/ULTSYM.2014.0552","url":null,"abstract":"In the medical ultrasound (US) community, only few simulators are able to fully simulate nonlinear wave propagation. In our recently developed software Creanuis [1], realistic nonlinear radio-frequency US images can be simulated. Unfortunately, the rather long computation time represents an important limitation, and is far from being comparable with the fastest simulation tools based on convolution strategies. In this work, a strategy combining Creanuis with a convolution appoach is proposed. This pseudo-acoustic nonlinear image strategy (PANIS) produces linear as well as nonlinear images. It consists to first simulate a set of punctual scatterers to locally extract a nonlinear point-spread function (PSF). Then, the 2D convolution of each of these PSF and the full medium is performed. The final PANIS image is obtained by selecting the specific part of each elementary convolved images. This final image contains the whole spectrum evolution with a depth dependent resolution and signal-to-noise ratio. The root-mean square error, between the statistics of PANIS and Creanuis images is kept under 1% and validates the model. The computation time is kept under 10 secondes for the convolution part.","PeriodicalId":153901,"journal":{"name":"2014 IEEE International Ultrasonics Symposium","volume":"189 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116342834","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}
Pub Date : 2014-10-23DOI: 10.1109/ULTSYM.2014.0495
F. Mitri
Based on the Rayleigh-Sommerfeld surface integral and the addition theorem for the spherical wave functions, a partial wave series expansion (PWSE) is derived for the incident field of an acoustical spiraling Laguerre-Gaussian vortex beam (LGVB). The description of the incident field in a PWSE in spherical coordinates allows efficient evaluation of the acoustic radiation force and torque on a sphere using the appropriate beam-shape coefficients. The finite vortex beam solution satisfies the Helmholtz equation, and can be used to advantage in beam-forming design and numerical prediction of the mechanical effects of sound LGVBs for applications in particle manipulation and the interaction of acoustic vortex beams with a particle.
{"title":"Acoustics of a finite-aperture Laguerre-Gaussian vortex beam","authors":"F. Mitri","doi":"10.1109/ULTSYM.2014.0495","DOIUrl":"https://doi.org/10.1109/ULTSYM.2014.0495","url":null,"abstract":"Based on the Rayleigh-Sommerfeld surface integral and the addition theorem for the spherical wave functions, a partial wave series expansion (PWSE) is derived for the incident field of an acoustical spiraling Laguerre-Gaussian vortex beam (LGVB). The description of the incident field in a PWSE in spherical coordinates allows efficient evaluation of the acoustic radiation force and torque on a sphere using the appropriate beam-shape coefficients. The finite vortex beam solution satisfies the Helmholtz equation, and can be used to advantage in beam-forming design and numerical prediction of the mechanical effects of sound LGVBs for applications in particle manipulation and the interaction of acoustic vortex beams with a particle.","PeriodicalId":153901,"journal":{"name":"2014 IEEE International Ultrasonics Symposium","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116376869","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}
Pub Date : 2014-10-23DOI: 10.1109/ULTSYM.2014.0166
Jianguo Ma, Xiaoning Jiang, K. H. Martin, P. Dayton, Yang Li, Qifa Zhou
Imaging of coronary vasa vasorum may lead to assessment of the vulnerable plaque development in diagnosis of atherosclerosis diseases. Intravascular ultrasound (IVUS) imaging transducers capable of detecting microvessels via nonlinear contrast imaging could provide valuable diagnostic information, however such transducers are not yet produced commercially. Dual-frequency transducers capable of detection of microbubble super-harmonics have shown promise as a new contrast-enhanced IVUS (CE-IVUS) platform. Contrast-to-tissue ratio (CTR) in CE-IVUS imaging can be closely associated with the low frequency transmitter performance. In this paper, multiple dual frequency IVUS transducers with different transmission frequencies (6.5 and 5 MHz) and different materials (PMN-PT single crystals and 1-3 composite) were developed and evaluated. All transducer structures were constructed with the 30 MHz high frequency reception element in front of the low frequency transmission element. Super-harmonic imaging was carried out using a tissue mimicking phantom. With similar peak negative pressures, the lower transmission frequency transducers generated higher CTR (23 dB for 5 MHz transmission). With similar input excitations, the PMN-PT 1-3 composite produced higher resolution (70 μm for 1-cycle burst excitation) than single crystal ones (> 150 μm). Dual frequency transducers with 5 MHz transmitters made of PMN-PT 1-3 composite are preferable in the CE-IVUS imaging.
{"title":"Dual frequency transducers for intravascular ultrasound super-harmonic imaging and acoustic angiography","authors":"Jianguo Ma, Xiaoning Jiang, K. H. Martin, P. Dayton, Yang Li, Qifa Zhou","doi":"10.1109/ULTSYM.2014.0166","DOIUrl":"https://doi.org/10.1109/ULTSYM.2014.0166","url":null,"abstract":"Imaging of coronary vasa vasorum may lead to assessment of the vulnerable plaque development in diagnosis of atherosclerosis diseases. Intravascular ultrasound (IVUS) imaging transducers capable of detecting microvessels via nonlinear contrast imaging could provide valuable diagnostic information, however such transducers are not yet produced commercially. Dual-frequency transducers capable of detection of microbubble super-harmonics have shown promise as a new contrast-enhanced IVUS (CE-IVUS) platform. Contrast-to-tissue ratio (CTR) in CE-IVUS imaging can be closely associated with the low frequency transmitter performance. In this paper, multiple dual frequency IVUS transducers with different transmission frequencies (6.5 and 5 MHz) and different materials (PMN-PT single crystals and 1-3 composite) were developed and evaluated. All transducer structures were constructed with the 30 MHz high frequency reception element in front of the low frequency transmission element. Super-harmonic imaging was carried out using a tissue mimicking phantom. With similar peak negative pressures, the lower transmission frequency transducers generated higher CTR (23 dB for 5 MHz transmission). With similar input excitations, the PMN-PT 1-3 composite produced higher resolution (70 μm for 1-cycle burst excitation) than single crystal ones (> 150 μm). Dual frequency transducers with 5 MHz transmitters made of PMN-PT 1-3 composite are preferable in the CE-IVUS imaging.","PeriodicalId":153901,"journal":{"name":"2014 IEEE International Ultrasonics Symposium","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122169914","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}
Pub Date : 2014-10-23DOI: 10.1109/ULTSYM.2014.0611
Wang Wen, Hu Yangqing, Liu Xinlu, He Shitang
This paper developed a surface acoustic wave (SAW) based accelerometer, it was composed of a flexible ST-X quartz cantilever beam with a relatively substantial proof mass at the undamped end, a pattern of two-port SAW resonator deposited directly on surface of the beam adjacent to the clamped end for maximum strain sensitivity, and a SAW resonator affixed on the metal package base for temperature compensation. The optimal dimensions of the cantilever beam were determined theoretically. Acceleration directed to the proof mass flex the cantilever, inducing relative changes in the acoustic propagation characteristics of the SAW traveling along the beams. The frequency signal from the differential oscillation structure utilizing the SAW resonators as the feedback element is used to characterize the applied acceleration. The sensor performance towards applied acceleration was evaluated by using the precise vibration table. High sensitivity, low detection limit and good linearity were observed in the acceleration experiments.
{"title":"Enhanced sensitivity of a surface acoustic wave based accelerometer","authors":"Wang Wen, Hu Yangqing, Liu Xinlu, He Shitang","doi":"10.1109/ULTSYM.2014.0611","DOIUrl":"https://doi.org/10.1109/ULTSYM.2014.0611","url":null,"abstract":"This paper developed a surface acoustic wave (SAW) based accelerometer, it was composed of a flexible ST-X quartz cantilever beam with a relatively substantial proof mass at the undamped end, a pattern of two-port SAW resonator deposited directly on surface of the beam adjacent to the clamped end for maximum strain sensitivity, and a SAW resonator affixed on the metal package base for temperature compensation. The optimal dimensions of the cantilever beam were determined theoretically. Acceleration directed to the proof mass flex the cantilever, inducing relative changes in the acoustic propagation characteristics of the SAW traveling along the beams. The frequency signal from the differential oscillation structure utilizing the SAW resonators as the feedback element is used to characterize the applied acceleration. The sensor performance towards applied acceleration was evaluated by using the precise vibration table. High sensitivity, low detection limit and good linearity were observed in the acceleration experiments.","PeriodicalId":153901,"journal":{"name":"2014 IEEE International Ultrasonics Symposium","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117088222","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}
Pub Date : 2014-10-23DOI: 10.1109/ULTSYM.2014.0237
M. Amini, A. Sinclair, T. Coyle
In this study, porous ceramics are introduced as a backing element suitable for high temperature transducers. Acoustic impedance and attenuation can be regulated through control of the porosity and pore size, using scattering from micropores as the attenuation mechanism. Porosity is induced by mixing the ceramic powder with polyethylene particles. The polymer component burns during the sintering process and leaves behind spherical voids. Porosity and pore size are controlled through the polymer-to-ceramic weight ratio and poltyethylene particle size, respectively. In this manner, a porous mullite material is designed and manufactured to act as the binding agent for a gallium phosphate (GaPO4) piezocrystal; this yields our goal of a wide-band signal with center frequency of 2.8 MHz and operating temperature up to 700 - 800 °C. The design and fabrication process can be employed in manufacturing backing elements for a variety of transducers with specified center frequency and signal bandwidth.
{"title":"Development of a high temperature transducer backing element with porous ceramics","authors":"M. Amini, A. Sinclair, T. Coyle","doi":"10.1109/ULTSYM.2014.0237","DOIUrl":"https://doi.org/10.1109/ULTSYM.2014.0237","url":null,"abstract":"In this study, porous ceramics are introduced as a backing element suitable for high temperature transducers. Acoustic impedance and attenuation can be regulated through control of the porosity and pore size, using scattering from micropores as the attenuation mechanism. Porosity is induced by mixing the ceramic powder with polyethylene particles. The polymer component burns during the sintering process and leaves behind spherical voids. Porosity and pore size are controlled through the polymer-to-ceramic weight ratio and poltyethylene particle size, respectively. In this manner, a porous mullite material is designed and manufactured to act as the binding agent for a gallium phosphate (GaPO4) piezocrystal; this yields our goal of a wide-band signal with center frequency of 2.8 MHz and operating temperature up to 700 - 800 °C. The design and fabrication process can be employed in manufacturing backing elements for a variety of transducers with specified center frequency and signal bandwidth.","PeriodicalId":153901,"journal":{"name":"2014 IEEE International Ultrasonics Symposium","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124058500","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}
Pub Date : 2014-10-23DOI: 10.1109/ULTSYM.2014.0533
U. Lok, Pai-Chi Li
The massive data transfer of ultrasound data becomes a critical issue of real time transmission for a GPU-based beamformer. Our previous study proposed a real time lossless compression/decompression algorithm to truncate unnecessary bits of ultrasound baseband data and provided compression ratio around 1.7. The compression ability of the previous method depends on the largest signal within a batch, if the location of the largest signal within a batch can be identified and suppressed; higher compression ratio can be achieved. Therefore, we propose the use of the fast Walsh transform (FWT) associated with the lossless compression method to suppress amplitude data to enhance the compression ability of the lossless compression approach. From the simulation results, the compression ratios and PSNRs reached nearly 2.1-2.7 and 42-48 dB, respectively. The extra processing times for FWT performed in hardware front end required several clock cycles. In addition, the inverse FWT of a frame data implemented in a GPU required several milliseconds only. These results show that FWT accompany with the lossless compression method can effectively compress data with reasonable latency. The proposed compression method is also embedded in a 64 channel ultrasound imaging system to verify the feasibility for a GPU-based beamforming system.
{"title":"Improving performance of GPU-based software beamforming using transform-based channel data compression","authors":"U. Lok, Pai-Chi Li","doi":"10.1109/ULTSYM.2014.0533","DOIUrl":"https://doi.org/10.1109/ULTSYM.2014.0533","url":null,"abstract":"The massive data transfer of ultrasound data becomes a critical issue of real time transmission for a GPU-based beamformer. Our previous study proposed a real time lossless compression/decompression algorithm to truncate unnecessary bits of ultrasound baseband data and provided compression ratio around 1.7. The compression ability of the previous method depends on the largest signal within a batch, if the location of the largest signal within a batch can be identified and suppressed; higher compression ratio can be achieved. Therefore, we propose the use of the fast Walsh transform (FWT) associated with the lossless compression method to suppress amplitude data to enhance the compression ability of the lossless compression approach. From the simulation results, the compression ratios and PSNRs reached nearly 2.1-2.7 and 42-48 dB, respectively. The extra processing times for FWT performed in hardware front end required several clock cycles. In addition, the inverse FWT of a frame data implemented in a GPU required several milliseconds only. These results show that FWT accompany with the lossless compression method can effectively compress data with reasonable latency. The proposed compression method is also embedded in a 64 channel ultrasound imaging system to verify the feasibility for a GPU-based beamforming system.","PeriodicalId":153901,"journal":{"name":"2014 IEEE International Ultrasonics Symposium","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128187663","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}
Pub Date : 2014-10-23DOI: 10.1109/ULTSYM.2014.0164
Sibo Li, Xiaoning Jiang, J. Tian, P. Han
We presented in this paper the development of micromachined 1-3 composite dual layer transducers for multifrequency imaging. The effective electromechanical coupling coefficient and acoustic impedance of the micromachined PMN-PT 1-3 composite material was measured to be 0.73 and 18 MRayl, respectively. Based on the material, a dual-layer transducer prototype was developed. The probe was operated at both 15 MHz and 48 MHz. To characterize the transducer, pulse echo test was conducted, achieved a 73% and 70% bandwidth at low and high resonance, respectively. At fundamental mode, it showed transmitting sensitivity of 26 KPa/V, These results suggested great potential for medical broadband imaging applications.
{"title":"Development of dual-layer micromachined composite transducers for broadband ultrasound imaging","authors":"Sibo Li, Xiaoning Jiang, J. Tian, P. Han","doi":"10.1109/ULTSYM.2014.0164","DOIUrl":"https://doi.org/10.1109/ULTSYM.2014.0164","url":null,"abstract":"We presented in this paper the development of micromachined 1-3 composite dual layer transducers for multifrequency imaging. The effective electromechanical coupling coefficient and acoustic impedance of the micromachined PMN-PT 1-3 composite material was measured to be 0.73 and 18 MRayl, respectively. Based on the material, a dual-layer transducer prototype was developed. The probe was operated at both 15 MHz and 48 MHz. To characterize the transducer, pulse echo test was conducted, achieved a 73% and 70% bandwidth at low and high resonance, respectively. At fundamental mode, it showed transmitting sensitivity of 26 KPa/V, These results suggested great potential for medical broadband imaging applications.","PeriodicalId":153901,"journal":{"name":"2014 IEEE International Ultrasonics Symposium","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127105781","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}
Pub Date : 2014-10-23DOI: 10.1109/ULTSYM.2014.0492
Hui Chen, Ji Wang, T. Ma, Jianke Du, Ju-lian Shen, Shih-Yung Pao, M. Chao
We study the calculation of electrical resistance of AT-cut quartz crystal resonators with the consideration of structural viscosity. A theoretical analysis of electrically forced vibrations of the coupled fundamental thickness-shear and spurious modes of a rectangular resonator model which is a partially electroded quartz crystal plate with free edges is performed. The equations are derived for calculating the electrical parameters, which can be used for the characterization of electronic devices, are obtained from the first-order Mindlin plate theory with the consideration of equivalent viscous dissipation of piezoelectric plates. Numerical results of the electrical resistance of resonators are obtained. It is found that through adding proper equivalent viscosity coefficient in electroded portion of the crystal plate, the calculated results of resistance is in good agreement with measurements from actual product samples.
{"title":"A calculation and validation of electrical resistance of quartz crystal resonators with structural viscosity","authors":"Hui Chen, Ji Wang, T. Ma, Jianke Du, Ju-lian Shen, Shih-Yung Pao, M. Chao","doi":"10.1109/ULTSYM.2014.0492","DOIUrl":"https://doi.org/10.1109/ULTSYM.2014.0492","url":null,"abstract":"We study the calculation of electrical resistance of AT-cut quartz crystal resonators with the consideration of structural viscosity. A theoretical analysis of electrically forced vibrations of the coupled fundamental thickness-shear and spurious modes of a rectangular resonator model which is a partially electroded quartz crystal plate with free edges is performed. The equations are derived for calculating the electrical parameters, which can be used for the characterization of electronic devices, are obtained from the first-order Mindlin plate theory with the consideration of equivalent viscous dissipation of piezoelectric plates. Numerical results of the electrical resistance of resonators are obtained. It is found that through adding proper equivalent viscosity coefficient in electroded portion of the crystal plate, the calculated results of resistance is in good agreement with measurements from actual product samples.","PeriodicalId":153901,"journal":{"name":"2014 IEEE International Ultrasonics Symposium","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127423185","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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