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Here are a few examples of my work.  It is a small fraction of what I have done over the  years in the area of acoustics and ultrasound.  The information has been edited to protect proprietary information.

Ultrasound Transducer Design and Specification

    A 40 kHz Therapeutic Ultrasound Applicator Head

    A Semi-formal Transducer Specification

Acoustic Wave Propagation and Sound Field Finite Element Analysis (FEA) using flexPDE

    Sound Field of a 5 MHz CW Cylindrical Source Transducer

    Vibrational Behavior of a Resonant Pyrex Wedge Waveguide

Multi-element Transducer Handpiece

       Handpiece

       Test Jig

       Ohmic Model UPDM-DT-1E Radiometer Enhancements

Comments Regarding my Design, measurement and Analysis Work in Ultrasound and Acoustics:

My early engineering career was mainly concerned with the design and project management of medical ultrasound systems for non-invasive imaging of the heart, carotid bifurcation and abdomen.  This work started when I was a graduate student at the University of Washington.

As a research assistant, I worked for ultrasound pioneer Don Baker in Dr. Robert Rushmer's Bioengineering Group.  I designed the signal processing circuitry for the world's first Duplex Doppler ultrasound scanner system. This and other related work resulted in my becoming Chief Engineer for Advanced Technology Laboratories (ATL), then a start up.

Working for able businessmen, and as a direct result of my personal design efforts, ATL grew to be a very large and successful medical imaging company.  Like Don Baker and a very few others, I have been noted as a pioneer of medical ultrasound and instruments that I designed have been on display in the Smithsonian.

Over time, ATL grew to be a large and successful medical imaging company and, in recent times, has been acquired by the medical division of the Dutch electronics giant, Phillips.

Subsequently, I started a small company dedicated to developing and manufacturing hydrophones, source transducers and scanning tanks for the purpose calibrating and measuring the diverse sound fields produced by medical ultrasound instruments.  I left this company, NTR Systems, Inc. (NTR), in 1995.  NTR still exists and has sold over 100 scanning tank systems into Japan, Europe and the USA ... a significant achievement for a very small company.

Later, I did the circuit and system design for an ultrasound instrument that measured cardiac output by means of Pulsed Doppler interrogation of the ascending aorta through the supra-sternal notch "window" into the body.

Some time following, I did circuit, system and multi-element transducer measurement, analysis and design for a sophisticated fetal heart monitor.

Between times and following, I have made a number of transducer designs, measurements and acoustic analyses of varying sorts.  This work has included the measurement of acoustic material properties in my automated scanning tank.

Ultrasound and acoustics is a great field to work in and, over the years, I have enjoyed doing the many tasks that came my way.

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