Acoustic focusing device with an interdigital transducer

In this paper a novel concept of the MFC based IDT, Tunable Interdigital Transducer (T-IDT), is presented. The proposed transducer is the extension of the MFC based IDT, where the solid comb electrodes are replaced by series of discrete, stripe electrodes which can be connected independently into the groups and connected to the power source. The span between the centers of the electrodes' groups connected to the same phase are corresponding to the nominal wavelength of the wave excited by the transducer. This makes possible matching to different wavelengths without a need of physical changes of the electrodes’ layout.

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Transduction Characteristics of a Surface Acoustic Wave Unidirectional Interdigital Transducer with Liquid Loading

Japanese Journal of Applied Physics ◽

10.1143/jjap.32.2384 ◽

1993 ◽

Vol 32 (Part 1, No. 5B) ◽

pp. 2384-2387

Author(s):

Masao Takeuchi ◽

Kazuhiko Yamanouchi

Keyword(s):

Acoustic Wave ◽

Surface Acoustic Wave ◽

Liquid Loading ◽

Interdigital Transducer

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Acoustic Focusing with Intensity Modulation Based on Sub-Wavelength Waveguide Array

Crystals ◽

10.3390/cryst11121461 ◽

2021 ◽

Vol 11 (12) ◽

pp. 1461

Author(s):

Mingran Zhang ◽

Guangrui Gu

Keyword(s):

Focal Length ◽

Intensity Modulation ◽

Waveguide Array ◽

Refractive Index Modulation ◽

Destructive Testing ◽

Equivalent Impedance ◽

Coding Method ◽

Acoustic Focusing ◽

Arbitrary Amplitude ◽

Sub Wavelength

Acoustic focusing with intensity modulation plays an important role in biomedical and life sciences. In this work, we propose a new approach for simultaneous phase and amplitude manipulation in sub-wavelength coupled resonant units, which has not been reported so far. Based on the equivalent impedance and refractive index modulation induced by the change of geometry, arbitrary amplitude response from 0 to 1 and phase shift from 0 to 2π is realized. Thus, the acoustic focusing with intensity modulation can be achieved via waveguide array. Herein, the focal length can be adjusted by alternating the length of supercell, and the whole system can work in a broadband of 0.872f0–1.075f0. By introducing the coding method, the thermal viscosity loss is reduced, and the wavefront modulation can be more accurate. Compared with previous works, our approach has the advantages of simple design and broadband response, which may have promising applications in acoustic communication, non-destructive testing, and acoustic holography.

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Droplets Transportation on a Piezoelectric Substrate with an Obstacle

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.339.104 ◽

2013 ◽

Vol 339 ◽

pp. 104-108

Author(s):

Xiang Ting Fu ◽

Yan Zha ◽

An Liang Zhang

Keyword(s):

Acoustic Wave ◽

Radio Frequency ◽

Surface Acoustic Wave ◽

Acoustic Streaming ◽

Microfluidic System ◽

Frequency Signal ◽

Radio Frequency Signal ◽

Generate Surface ◽

Interdigital Transducer ◽

Piezoelectric Substrate

A method for a droplet transportation by jumping a obstacle on piezoelectric substrate is presented, and a device for the droplet transportation is implemented on a 128° yx-LiNbO3 piezoelectric substrate. An interdigital transducer and a reflector are fabricated on the piezoelectric substrate using microelectric technology. Hydrophobic film is coated on the area free of electrodes and a polydimethylsilicone obstacle is mounted on it. A radio frequency signal amplified by a power amplifier is applied to the interdigital transducer to generate surface acoustic wave. When the surface acoustic wave meets with the droplet on the piezoelectric substrate during transportation, part of acoustic wave enegy is radiated into the droplet, leading to internal acoustic streaming. Once the radio frequency signal with appropriate amplitude is suddenly decreased, part of the droplet will jump the obstacle due to interial force. Red dye solution drops are demonstrated for transportation experiments. Results show that a droplet can be transported from one side to another of the obstacle on piezoelectric substrate by help of surface acoustic wave. The presented method is helpful for microfluidic system on a piezoelectric substrate.

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Manipulation of acoustic focusing with an active and configurable planar metasurface transducer

Scientific Reports ◽

10.1038/srep06257 ◽

2014 ◽

Vol 4 (1) ◽

Cited By ~ 49

Author(s):

Jiajun Zhao ◽

Huapeng Ye ◽

Kun Huang ◽

Zhi Ning Chen ◽

Baowen Li ◽

...

Keyword(s):

Acoustic Focusing

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