Ultrasound

Go Back a Page           Return to Home Page


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 Acoustic Waveguide

Multi-element Transducer Handpiece

    Handpiece

Broadband Acoustic Wave Test Jig for a Multi-element Transducer

    Test Jig

Modifications to an Ohmic Instruments Radiation Force Balance

    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 (left and right sides of the neck) 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 much of 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 ... and now, Phillips Ultrasound.

Run by 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, diagnostic instruments that I designed have been on display in the Smithsonian.

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. Cardiac output is an important physiologic parameter.

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 an 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.


Go Back a Page           Return to Home Page


        Copyright © 2022 [Nelson Research, Inc]. All rights reserved.
        Send mail to craig@nelsonresearchinc.com with questions or comments about this web site.