Two-way Insertion Loss Research Articles

Textured ferroelectric ceramics based 1–3 piezoelectric composite for photoacoustic imaging

The quality of ultrasound and photoacoustic imaging primarily depends on the performance of piezoelectric transducer elements, which is closely related to the acoustic and electrical properties of piezoelectric materials. With the increasing demand for high-performance, low-cost piezoelectric materials, a high-temperature-resistant <001>-textured ferroelectric ceramic Pb(In1/2Nb1/2)O3-Pb(Sc1/2Nb1/2)O3-PbTiO3 (PIN-PSN-PT) has been developed. In recent years, low-cost textured ceramic materials have exhibited high piezoelectric constants (d33) and large electromechanical coupling coefficients (kt). In this study, an ultrasonic transducer based on PIN-PSN-PT textured ceramic was successfully manufactured for the first time. The transducer has a center frequency of 4.7 MHz, −6 dB bandwidth of 60 %, effective kt of 0.76, and two-way insertion loss (IL) of −34 dB. Photoacoustic imaging experiments on carbon fiber-reinforced polymer (CFRP) were conducted to evaluate the sensitivity and imaging quality of the transducer. The results indicate that the use of PIN-PSN-PT textured ceramics holds great potential in developing acoustic sensors for photoacoustic non-destructive testing applications.

Design, fabrication, and characterization of 1–3 piezoelectric composite air-coupled ultrasonic transducers with micro-membrane filter matching layer

Air-coupled ultrasonic transducers are widely used in various fields of nondestructive material characterization. This paper presents the fabrication and performance characterization of 1–3 piezoelectric composite air-coupled ultrasonic transducers operating at frequencies ranging from 400 kHz to 600 kHz. The transducers are fabricated using a dice-and-fill method with PZT-5 as the active material. A double-layer matching strategy is employed, utilizing hollow glass microsphere filled epoxy resin as the first matching and bonding layer. Additionally, micro-membrane filters with different pore sizes are used as the second matching layer. Thermoplastic adhesive TPU is utilized to bind the micro-membrane filter and the first matching layer. Due to the low acoustic impedance of the hollow glass microsphere filled epoxy resin and micro-membrane filter, acoustic impedance mismatch is reduced. Finite element simulation is used to determine the optimal ceramic volume fraction and ceramic pillar height of the 1–3 piezoelectric composites. When the pore size of the micro-membrane filter is 0.8 μm, the transducer achieves the lowest two-way insertion loss of −56.86 dB and the highest −6 dB bandwidth of 15.6 %, making it feasible for through mode applications.

Micromachining of High-Quality PMN-PT/Epoxy 1-3 Composite for High-Frequency (>30 MHz) Ultrasonic Transducer Applications.

Fabricating PMN-PT composites, the core component of high-frequency (>30 MHz) transducers, remains challenging due to their poor machinability and ultra-small kerfs. This urgent problem is significantly impeding the development of PMN-PT ultrasonic transducers for use in clinical research, biomedical sciences, and nondestructive testing. In this study, high-quality PMN-0.3PT/epoxy 1-3 composites at 30 MHz and 50 MHz were manufactured using a modified picosecond (1.5 ps) laser technique. Their performance was thoroughly analyzed, which was comparable to that with low-stress dry plasma etching. There were fewer microcracks around PMN-PT pillars. The minimum kerf was less than 4.5 μm and the highest aspect ratio was larger than 7.5. The micro domain morphology and hysteresis loops of PMN-PT pillars further confirmed that composites still maintained excellent piezoelectric performance and suffered fewer damages during laser cutting. The characterization results exhibited a large electromechanical coupling (>0.77), a high dielectric constant (>1600), and a relatively low acoustic impedance (<17 Mrayls). The ultrasonic transducers with centre frequencies of 30 MHz and 50 MHz were designed and prototyped to validate the performance of composites. The transducers showed broad bandwidth (>80%), high two-way insertion loss (>-23 dB), and imaging resolution superior to 40 μm. Finally, the C-scan experiments of IC chips were also used to further illustrate the applicability of transducers. These encouraging results further demonstrated that ultrafast laser technology will bring more accessible and affordable methods for fabricating high-frequency PMN-PT composite transducers with excellent performance.

Development of Cardiac Phased Array With Large-Size PZN-5.5 %PT Single Crystals.

In recent years, the manufacturing process of lead zinc niobate-lead titanate [Pb(Zn1/3Nb2/3)O3-PbTiO3, also called PZN-PT], has been enhanced with improvements in size, consistency, and a suitable compromise between piezoelectric properties and phase transition temperature, which means that it is possible to obtain PZN-PT single crystals in sufficient size for performance characterization studies and batch manufacturing to produce high-performance medical ultrasonic transducers. This article mainly focuses on the development of the 64-element phased array ultrasonic transducer based on novel large-size PZN-PT piezoelectric single crystals. The composition of the single crystal was chosen as PZN-5.5 %PT. The designed center frequency of the phased array is 3.0 MHz, which is suitable for cardiac ultrasound imaging. The array elements were spaced at a 0.254-mm pitch, and interconnected through a custom-designed flexible circuit. Double matching layers with a light backing structure were applied in the transducer fabrication process to improve the performance of the array. The test results of the developed phased array showed a center frequency of 3.0 MHz, and an average -6 dB fractional bandwidth of 72%. In the vicinity of the center frequency, the two-way insertion loss (IL) was about -46 dB, while a crosstalk between the adjacent elements was less than -31 dB. The wire phantom can be distinctly imaged with the phased array, and the axial and lateral resolutions were measured to be 660 and [Formula: see text], respectively. The image of a standard phantom was acquired to present the imaging performance of the transducer. The final results indicate that the transducer arrays based on novel large-size PZN-PT single crystals are quite promising for use in medical ultrasound imaging applications.

Electronic Mode Stirring for Improved Backscatter Communication Link Margin in a Reverberant Cavity Animal Cage Environment

Neuroscience research in nonhuman primates (NHPs) often requires multiday neural recordings from freely moving animals inside their home cages, making ultralow-power uplinks using wireless backscatter communication highly desirable. Previous work reveals that the channel transfer function (CTF) of a standard NHP home cage in the 915 MHz and 2.4 GHz industrial, scientific, and medical (ISM) bands resembles a resonant cavity exhibiting deep nulls throughout the cage volume, which are particularly acute for round-trip backscatter paths. In this work, we investigate a novel application of passive antenna mode stirring via switched parasitic antennas (SPAs) to reduce the magnitude and prevalence of deep nulls in the cage CTF. We present a system leveraging four cage-ceiling-mounted SPAs with two dynamically controlled impedance states each, yielding 16 total mode stirring configurations. We compare the frequency-domain power ratio measurements at 126 positions throughout the cage taken with and without passive antenna mode stirring. In the 915 MHz ISM band, the optimized SPA configuration improved the maximum two-way insertion loss in 68% of testing locations, reducing the worst case two-way insertion loss by 60.2 dB. In the 2.4 GHz ISM band, the maximum two-way insertion loss was improved in 53% of testing locations, reducing the worst case two-way insertion loss by 35.6 dB. This approach eliminates the deepest nulls in the cage volume and leads to significantly improved link margin for a backscatter-based wireless brain–computer interface (BCI).

Acoustic Hole-Hologram for Ultrasonic Focusing With High Sensitivity

Acoustic hologram enable the capability in the acoustic pattern control and drive many applications of ultrasound. However, hologram has not been applied to ultrasound imaging because the medical application of acoustic holograms is limited owing to the sound reflection and scattering at the acoustic holographic surface and its internal attenuation. In this study, we propose an acoustic holographic computing method and present a disc-shaped hologram with a central hole comparing with a conventional hologram using the iterative angular spectrum approach. The results show that the transducer with hole hologram achieves the required focusing effect with the full width at half maximum about <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1.5\lambda $ </tex-math></inline-formula> , high sensitivity increased by 92.7%, and a low two-way insertion loss with −15.8 dB compared to conventional hologram. Pulse-echo and ultrasonic imaging are achieved by a transducer with two holograms which shows new applications of acoustic hologram in ultrasound.

1.5-Dimensional Circular Array Transducer for In Vivo Endoscopic Ultrasonography.

Traditional endoscopic ultrasonography (EUS), which uses one-dimensional (1-D) curvilinear or radial/circular transducers, cannot achieve dynamic elevational focusing, and the slice thickness is not sufficient. The purpose of this study was to design and fabricate a 1.5-dimensional (1.5-D) circular array transducer to achieve dynamic elevational focusing in EUS in vivo. An 84 × 5 element 1.5-D circular array transducer was successfully developed and characterized in this study. It was fabricated with PZT-5H 1-3 composite that attained a high-electromechanical coupling factor and low-acoustic impedance. The acoustic field distribution was measured with different transmission modes to validate the 1.5-D elevational beam focusing capability. The imaging performance of the 84 × 5 element 1.5-D circular array transducer was evaluated by two wire phantoms, an agar-based cyst phantom, an ex vivo swine pancreas, and an in vivo rhesus macaque rectum based on multifocal ray-line imaging method with five-row elevational beam steering. It was demonstrated that the transducer exhibited a central frequency of 6.47 MHz with an average bandwidth of 50%, a two-way insertion loss of 23 dB, and crosstalk of <-26 dB around the center frequency. Dynamic elevational focusing and the enhancement of the slice thickness in EUS were obtained with a 1.5-D circular array transducer. This study promotes the development of multirow and two-dimensional array EUS probes for a more precise clinical diagnosis and treatment.

KNNS-BNZH Lead-Free 1-3 Piezoelectric Composite for Ultrasonic and Photoacoustic Imaging.

In this paper, lead-free 0.965(K0.45Na0.55) (Nb0.96Sb0.04)O3-0.0375Bi0.5Na0.5Zr0.85Hf0.15O3 (KNNS-BNZH)/epoxy 1-3 composite was designed and fabricated with the dice-and-fill method. The composite material exhibited a high thickness electromechanical coupling coefficient ( kt = 0.7 ), high piezoelectric constant ( d33 = 350 pC N-1), relatively low mechanical quality factor ( Qm = 5 ), and relatively low acoustic impedance. An ultrasonic transducer with a center frequency of 5 MHz was produced based on the 1-3 KNNS-BNZH/epoxy composite, showing a broad bandwidth of 80% (-6 dB) and two-way insertion loss of -30 dB. Ultrasonic and photoacoustic images were further demonstrated. The outstanding performance of the 1-3 KNNS-BNZH/epoxy composite transducer competitive to Pb(Zr1-xTix)O3 (PZT)-based transducers suggests that the lead-free material can serve as a promising alternative to Pb-based piezoelectric materials for ultrasonic applications.

Miniaturized High-Resolution Integrated 360° Electronic Radial Ultrasound Endoscope for Digestive Tract Imaging.

To improve the accuracy and operating flexibility of digestive diagnostic applications in situ, this paper demonstrates the design, fabrication, and evaluation of a miniaturized high-resolution integrated 360° electronic radial ultrasound endoscope. To improve the uniformity between elements of the radial array transducer, an optimal fabrication procedure based on a flexible matching layer was developed. The radial ultrasound endoscope has a 128.3° 5-million-pixel camera module integrated with an approximately 8-MHz 128-element radial ultrasonic array in a package with an outer diameter of 9.5 mm. The results showed that the array has a center frequency of 8.2 MHz, a -6-dB fractional bandwidth of 83.4%, and a two-way insertion loss of 39.62 dB at the center frequency. Annulus and wire phantoms can be distinctly imaged with the radial array. Printed eight-point font can be distinctly imaged with both a large view and a 3-18-mm depth of field in lumen short-range optical imaging. A porcine esophagus can be distinctly imaged in vitro with the integrated endoscope. The results indicate that the fabrication method based on a flexible matching layer can achieve high uniformity between elements of a radial array transducer. In addition, the proposed ultrasound endoscope demonstrates a good image resolution.

Magnesium Alloy Matching Layer for High-Performance Transducer Applications

In this paper, we report the use of magnesium alloy (AZ31B) as the matching material for PZT-5H ultrasonic transducers. The AZ31B has an acoustic impedance of 10.3 MRayl, which provides a good acoustic impedance match for PZT-5H ultrasonic transducers in water medium based on the double matching layer theory. Two PZT-5H transducers with different center frequencies were designed and fabricated using the AZ31B. The respective center frequencies of the two fabricated transducers were 4.6 MHz and 9.25 MHz. The 4.6 MHz transducer exhibits a −6 dB bandwidth of 79% and two-way insertion loss of −11.11 dB. The 9.25 MHz transducer also shows good performance: −6 dB bandwidth of 71% and two-way insertion loss of −14.43 dB. The properties of the two transducers are superior to those of transducers using a composite matching layer, indicating that the magnesium alloy may be a promising alternative for high-performance transducers.

Eco-Friendly Highly Sensitive Transducers Based on a New KNN-NTK-FM Lead-Free Piezoelectric Ceramic for High-Frequency Biomedical Ultrasonic Imaging Applications.

High-frequency ultrasonic imaging with improved spatial resolution has gained increasing attention in the field of biomedical imaging. Sensitivity of transducers plays a pivotal role in determining ultrasonic image quality. Conventional ultrasonic transducers are mostly made from lead-based piezoelectric materials that may be harmful to the human body and the environment. In this study, a new (K,Na)NbO3-KTiNbO5-BaZrO3-Fe2O3-MgO (KNN-NTK-FM) lead-free piezoelectric ceramic was utilized in developing eco-friendly transducers for high-frequency biomedical ultrasonic imaging applications. A needle transducer with a small active aperture size of 0.45 × 0.55 mm2 was designed and evaluated. The fabricated transducer exhibits great performance with a high center frequency (52.6 MHz), a good electromechanical coupling (keff ∼ 0.45), a large bandwidth (64.4% at -6 dB), and a very low two-way insertion loss (10.1dB). Such high sensitivity is superior to those transducers based on other lead-free piezoelectric materials and can even be comparable to the lead-based ones. Imaging performance of the KNN-NTK-FM needle transducer was analyzed by imaging a wire phantom and an agar tissue-mimicking phantom. Imaging capabilities of the transducer were further demonstrated by ex vivo imaging studies on a porcine eyeball and a rabbit aorta. The results suggest that the KNN-NTK-FM piezoceramic has many attractive properties over other lead-free piezoelectric materials in developing eco-friendly highly sensitive transducers for high-frequency biomedical ultrasonic imaging applications.

Development of a KNN Ceramic-Based Lead-Free Linear Array Ultrasonic Transducer.

High-frequency array transducers can provide higher imaging resolution than traditional transducers, thus resolving smaller features and producing finer images. Commercially available ultrasonic transducers are mostly made with lead-based piezoelectric materials, which are harmful to the environment and public health. This paper presents the development of the 64-elements high-frequency (18.3 MHz) lead-free linear array ultrasonic transducer based on (K0.44Na0.52Li0.04)(Nb0.86Ta0.1Sb0.04)O3 (KNLNTS) piezoceramic. Array elements were spaced at a 75- pitch, and interconnected via a custom flexible circuit. The two matching layers and a light backing material were used to improve the performance of the array. The developed KNLNTS ceramic-based lead-free linear array exhibited a center frequency of 18.3 MHz, an average -6-dB bandwidth of 42%, an average two-way insertion loss of 41.8 dB, and a crosstalk between the adjacent elements of less than -53 dB near the center frequency. An image of a tungsten wire phantom was acquired using a Verasonics Vantage research ultrasound system. Results from imaging tests demonstrated a good imaging capability with a spatial resolution of axially and laterally, indicating that the lead-free linear array ultrasonic transducer based on KNLNTS ceramics is a promising alternative to lead-based transducers for ultrasound medical imaging.

Magnesium Alloy Matching Layer for PMN-PT Single Crystal Transducer Applications.

In this paper, we propose using magnesium alloy as the matching layer for the ultrasonic transducer made of 0.68 Pb(Mg1/3Nb2/3)O3-0.32PbTiO3 (PMN-0.32PT) single crystal. The complete sets of elastic constants of AZ31B, GW83, and ZK60 magnesium alloys have been measured, which is practically a homogeneous material. The AZ31B magnesium alloy has an acoustic impedance of 10.36 MRayl, which is suitable for the development of high-performance ultrasonic transducers. A 3.5-MHz PMN-PT single crystal transducer has been designed and fabricated successfully using AZ31B magnesium alloy as the first quarter-wavelength matching layer. The -6-dB bandwidth and two-way insertion loss at the center frequency of the transducer are about 67% and 11.4 dB, respectively, much superior to the transducer fabricated using 0-3 composite matching layer. The high performance of this transducer indicates that the magnesium alloy is indeed an excellent matching layer material for ultrasonic transducer applications.

A Novel Synchronous Micro Motor for Intravascular Ultrasound Imaging.

Intravascular ultrasound (IVUS) is an important method for evaluating lumen dimensions and guiding intervention. However, the current IVUS catheter using a proximal motor and flexible drive shaft is easily rotated at an unstable speed when it passes through along bending vessel. One approach to solve this problem is to develop a catheter driven by a distal motor. This paper presents a rotation device incorporating a high-frequency transducer as an attempt to facilitate this approach. A novel micro distal synchronous micro motor with 3.7 mm length and 1.2 mm outer diameter was proposed as an actuator for the IVUS catheter. A 0.5 mm × 0.5 mm Pb(Mg1/3Nb2/3)O3-PbTiO3 single crystal 1-3 composite single-element transducer was designed and manufactured. The probe is fixed to the front end of the catheter. The 45° reflector, which is opposite to the probe, was used to steer ultrasound to the tissue. The results showed that the maximum torque and rotation speed of the motor were 2.79 μNm and 275 revolutions per second, respectively, at a driving current of 0.34 A. The maximum angular error was 7° at 0.13 A and 30Hz. The center frequency and -6 dB fractional bandwidth of single element were 34MHz and 72%, respectively. At the center frequency, the two-way insertion loss was 14 dB. The integrated distal motor IVUS catheter, with small dimensions, a good torque, speed stability, and good ultrasound imaging performance, has tremendous potential in blood vessel imaging. The novel structure of the catheter could facilitate endoluminal sonography, reducing risks of the clinical diagnosis.

Fabrication and Performance of a Miniaturized and Integrated Endoscope Ultrasound Convex Array for Digestive Tract Imaging.

this work presents the design, fabrication, and testing of a miniaturized and integrated ultrasound endoscope for use as an in situ digestive diagnostic device to facilitate real-time ultrasound guidance of intervention treatments. we designed an optimal structure to integrate an auto-focus 5-megapixel camera module with an 8-MHz, 64-element curvilinear ultrasonic array in one miniaturized package. A novel three-axis auto-focusing voice coil motor (VCM) was designed and manufactured for the camera module to move the lens position for auto-focusing and to adjust the lens tilt. the results showed that the array had a center frequency of 8.09MHz and a -6-dB fractional bandwidth of 83%. At the center frequency, the two-way insertion loss was 40.6dB. Endoscopic ultrasound imaging demonstrated satisfactory performance for imaging an anthropomorphic phantom of the esophagus. By slightly adjusting the tilt angle of the optical axis of the lens, the optical image captured by the auto-focusing lens obtained improved definition regardless of changes in the view angle of the camera with respect to the objects being captured. the integrated convex ultrasound endoscope, possessing minimal size, improved optical imaging definition, and good ultrasound imaging performance, can become a useful tool in digestive tract imaging. the miniaturized and integrated convex ultrasound endoscope can facilitate real-time ultrasound intervention guidance, reducing risks associated with the operation.

Development of an 83.2 MHz, 3.2 kW solid-state RF amplifier using Wilkinson power divider and combiner for a 10 MeV cyclotron.

We design a stripline-type Wilkinson power divider and combiner for a 3.2 kW solid-state radio frequency (RF) amplifier module and optimize this setup. A Teflon-based printed circuit board is used in the power combiner to transmit high RF power efficiently in the limited space. The reflection coefficient (S11) and insertion loss (S21) related to impedance matching are characterized to determine the optimization process. The resulting two-way divider reflection coefficient and insertion loss were -48.00 dB and -3.22 dB, respectively. The two-way power combiner reflection coefficient and insertion loss were -20 dB and -3.3 dB, respectively. Moreover, the 3.2 kW solid-state RF power test results demonstrate that the proposed power divider and combiner exhibit a maximum efficiency value of 71.3% (combiner loss 5%) at 48 V supply voltage.

Anodic aluminum oxide–epoxy composite acoustic matching layers for ultrasonic transducer application

The goal of this work is to demonstrate the application of anodic aluminum oxide (AAO) template as matching layer of ultrasonic transducer. Quarter-wavelength acoustic matching layer is known as a vital component in medical ultrasonic transducers to compensate the acoustic impedance mismatch between piezoelectric element and human body. The AAO matching layer is made of anodic aluminum oxide template filled with epoxy resin, i.e. AAO–epoxy 1–3 composite. Using this composite as the first matching layer, a ∼12MHz ultrasonic transducer based on soft lead zirconate titanate piezoelectric ceramic is fabricated, and pulse-echo measurements show that the transducer exhibits very good performance with broad bandwidth of 68% (−6dB) and two-way insertion loss of −22.7dB. Wire phantom ultrasonic image is also used to evaluate the transducer’s performance, and the results confirm the process feasibility and merit of AAO–epoxy composite as a new matching material for ultrasonic transducer application. This matching scheme provides a solution to address the problems existing in the conventional 0–3 composite matching layer and suggests another useful application of AAO template.

Fabrication and performance of a 64 × 5 element 1.5D active matrix array transducer for medical imaging

Compared to 1D phased array probes with a fixed focus in elevation, multi-row arrays can significantly improved the slice thickness throughout image by expanding aperture and dynamic focusing in elevation. This paper describes the design and measurement of a 64×5 element 1.5D ultrasonic transducer that enables dynamic focusing and apodization in the elevation direction. We manufactured a transducer with an aperture size of 24mm×16mm using a widely used piezoelectric ceramic (PZT-5H) as the piezoelectric vibrator. The measured center frequency and −6dB fractional bandwidth of the 1.5D transducer were 3MHz and 79%, respectively. A two-way insertion loss of −58dB was obtained at the average center frequency. We carried out a sound field simulation and measured the actual transmitting (one-way) sound field data by using a hydrophone. In this way the sound beam profile in elevation direction was obtained, showing the −6dB slice thickness measured was about 2mm throughout the whole range of interest (from near to far field). This provided a much greater focal depth and much better imaging resolution in the elevation direction than can be achieved by using 1D probe.

Microfabrication of stacks of acoustic matching layers for 15 MHz ultrasonic transducers

This paper presents a novel method used to manufacture stacks of multiple matching layers for 15MHz piezoelectric ultrasonic transducers, using fabrication technology derived from the MEMS industry. The acoustic matching layers were made on a silicon wafer substrate using micromachining techniques, i.e., lithography and etch, to design silicon and polymer layers with the desired acoustic properties. Two matching layer configurations were tested: a double layer structure consisting of a silicon–polymer composite and polymer and a triple layer structure consisting of silicon, composite, and polymer. The composite is a biphase material of silicon and polymer in 2-2 connectivity. The matching layers were manufactured by anisotropic wet etch of a (110)-oriented Silicon-on-Insulator wafer. The wafer was etched by KOH 40wt%, to form 83μm deep and 4.5mm long trenches that were subsequently filled with Spurr’s epoxy, which has acoustic impedance 2.4 MRayl. This resulted in a stack of three layers: The silicon substrate, a silicon–polymer composite intermediate layer, and a polymer layer on the top. The stacks were bonded to PZT disks to form acoustic transducers and the acoustic performance of the fabricated transducers was tested in a pulse-echo setup, where center frequency, −6dB relative bandwidth and insertion loss were measured. The transducer with two matching layers was measured to have a relative bandwidth of 70%, two-way insertion loss 18.4dB and pulse length 196ns. The transducers with three matching layers had fractional bandwidths from 90% to 93%, two-way insertion loss ranging from 18.3 to 25.4dB, and pulse lengths 326 and 446ns. The long pulse lengths of the transducers with three matching layers were attributed to ripple in the passband.

Broadband ultrasonic linear array using ternary PIN-PMN-PT single crystal

Ternary Pb(In(1/2)Nb(1/2))O(3)-Pb(Mg(1/3)Nb(2/3))O(3)-PbTiO(3) (PIN-PMN-PT) single crystal was investigated for potential application in ultrasonic linear array. Orientation and temperature dependences of height extensional electromechanical coupling coefficient k'(33) for PIN-PMN-PT single crystal were studied. It was found that the [001] poled PIN-PMN-PT diced along the [100] direction would achieve a maximum k'(33) (~87%) and the service temperature was up to 110 °C. Ultrasonic linear arrays using PIN-PMN-PT single crystal and PZT ceramic were fabricated and compared. The bandwidth at -6 dB, two-way insertion loss and pulse length of the PIN-PMN-PT array were 98.6%, -45.1 dB, and 0.28 μs, respectively, which were about 25% broader, 3.7dB higher, and 0.08 μs shorter than those of the PZT array. The experimental results agreed well with the theoretical simulation. These superior performances were attributable to the excellent piezoelectric properties of PIN-PMN-PT single crystal.