• Analyse av en Ultralyd Transduser med et Laser Doppler Vibrometer 

      Nilsen, Mikael Isak (Master thesis, 2021)
      Ultrasonic transducers are an integral part of underwater imaging, with a wide range of applications. In this thesis, analysis of a underwater echo sounder transducer operating at 200kHz is done underwater with a Laser ...
    • Characterization of Layers with Metal-Coated Polymer Spheres for use in Ultrasound Transducers 

      Nicolaisen, Anette Sollien (Master thesis, 2021)
      The properties of materials used in ultrasound transducers affect the properties of the finished transducer, making it important to characterize the acoustic properties of these materials. The study in this thesis is ...
    • Estimating Regional Myocardial Contraction Using Miniature Transducers on the Epicardium 

      Nguyen, Thu Thuy; Espinoza, Andreas Westenvik; Hyler, Stefan; Remme, Espen W.; D'Hooge, Jan; Hoff, Lars (Peer reviewed; Journal article, 2019)
      This paper describes an ultrasound system to monitor cardiac motion using miniature transducers attached directly to the epicardial surface. Our aim was to develop both a research tool for detailed studies of cardiac ...
    • Fabrication and Characterization of a Low-Frequency Array for a Hybrid PZT-CMUT Transducer 

      Siu, Hoi Yi (Master thesis, 2021)
      Piezocomposite materials consist of a periodic structure of active piezoelectric materials and passive polymer materials. Piezocomposite material is widely used in medical ultrasound transducers due to the advantages of ...
    • Heat generation in underwater transducers 

      Wild, Marcus Sebastian (Doctoral dissertations at the University of South-Eastern Norway;38, Doctoral thesis, 2019)
      Acoustic transducers are used for a variety of applications, ranging from medical to maritime uses. In the maritime sector, underwater transducers can be used for appli- cations such as seabed mapping, fishing and ...
    • Intermetallic bonding as an alternative to polymeric adhesives in ultrasound transducers 

      Bolstad, Per Kristian; Le, Anh Duy; Hoff, Lars; Manh, Tung (Peer reviewed; Journal article, 2019)
      Common ultrasound transducers utilize epoxy for bonding the active piezoelectric to the rest of the acoustic stack. This paper explores some of the potential benefits of replacing this soft epoxy layer with a harder ...
    • Nonlinearity in a medical ultrasound probe under high excitation voltage 

      Huynh, Thong; Haugen, Geir Ultveit; Eggen, Trym Haakon; Hoff, Lars (Peer reviewed; Journal article, 2020)
      Tissue harmonic imaging is often the preferred ultrasound imaging modality due to its ability to suppress reverberations. The method requires good control of the transmit stage of the ultrasound scanner, as harmonics in ...
    • Numerical optimization of ultrasound transducers by the linearity of the phase spectrum 

      Andersen, Kenneth Kirkeng; Frijlink, Martijn Egbert; Hoff, Lars (Journal article; Peer reviewed, 2017)
      New ultrasound imaging and therapeutic modalities may require transducer designs that are not easily facilitated by conventional design guidelines and analytical expressions. This motivates the investigation of numerical ...