Development and Evaluation of a Close-Proximity, Real Time Thermoacoustic Ultrasound Sensor

• Author / Creator

  Choi, Michael

• A close proximity, real time thermoacoustic sensor was designed, tested, and implemented in the SonaCell ultrasound generator. When placed in contact with the SonaCell ultrasound transducer, a copper backed plexiglass absorber converted ultrasound energy into heat, where it was measured by a thermistor on the back face of the absorber. A transient model was used to calculated ultrasound intensity from temperature data by fitting the curve Tave=C(1-e^((-t)/τ) )+ T0 to the measured data using a least squares method and relating the coefficient C to the applied ultrasound intensity. Over an ultrasound intensity range of 30 mW/cm^2 to 100 mW/cm^2 the thermoacoustic sensor was able to calculate ultrasound intensities with an average error of 8.38% and a maximum observed standard deviation of 5.00 mW/cm^2 when compared to measurements made with a radiation force balance. Analysis of the model and a full evaluation of the designed sensor was carried out.

• Subjects / Keywords

  • Ultrasound Calibration
  • Ultrasound Sensor
  • Thermoacoustic Sensor

• Graduation date

  Spring 2012

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3S91G

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.