Conference paper
Output pressure and harmonic characteristics of a CMUT as function of bias and excitation voltage
Department of Micro- and Nanotechnology, Technical University of Denmark1
MEMS-AppliedSensors, Department of Micro- and Nanotechnology, Technical University of Denmark2
Department of Electrical Engineering, Technical University of Denmark3
Biomedical Engineering, Department of Electrical Engineering, Technical University of Denmark4
Center for Fast Ultrasound Imaging, Centers, Technical University of Denmark5
The large bandwidth makes CMUT based transducers interesting for both conventional and harmonic imaging. The inherent nonlinear behavior of the CMUT, however, poses an issue for harmonic imaging as it is difficult to dissociate the harmonics generated in the tissue from the harmonic content of the transmitted signal.
The generation of intrinsic harmonics by the CMUT can be minimized by decreasing the excitation signal. This, however, leads to lower fundamental pressure which limits the desired generation of harmonics in the medium. This work examines the output pressure and harmonic characteristics of a CMUT as function of bias and excitation voltage.
The harmonic to fundamental ratio of the surface pressures declines for decreasing excitation voltage and increasing bias voltage. The ratio, however, becomes unchanged for bias levels close to the pull-in voltage. The harmonic limitations of the CMUT is emphasized by a maximum ratio of −12 dB between harmonics generated in the medium and total harmonics measured at 10 mm.
| Language: | English |
|---|---|
| Publisher: | IEEE |
| Year: | 2015 |
| Pages: | 1-4 |
| Proceedings: | 2015 IEEE International Ultrasonics Symposium |
| ISBN: | 1479981818 , 1479981826 , 1479981834 , 9781479981816 , 9781479981823 and 9781479981830 |
| Types: | Conference paper |
| DOI: | 10.1109/ULTSYM.2015.0467 |
| ORCIDs: | Lei, Anders , Diederichsen, Søren Elmin , Stuart, Matthias Bo , Bouzari, Hamed , Jensen, Jørgen Arendt and Thomsen, Erik Vilain |
Acoustic measurements CMUT based transducer Harmonic analysis Imaging Pressure measurement Sensitivity Sonar equipment Ultrasonic variables measurement capacitance measurement capacitive micromachined ultrasonic transducer capacitive transducers excitation signal excitation voltage gain -12 dB harmonic generation harmonic imaging characteristics harmonics generation microsensors output pressure characteristics pressure measurement pressure transducers pull-in voltage tissue ultrasonic transducers
