4aEA2. Practical implications of micromachined ultrasonic transducers.

Session: Thursday Morning, May 16

Time: 8:15

Author: Igal Ladabaum
Author: Butrus T. Khuri-Yakub
Location: Stanford Univ., E. L. Ginzton Lab., Stanford, CA 94305


Micromachined ultrasonic transducers capable of airborne transmission of 1- to 12-MHz ultrasound have been reported. It has also been reported that these transducers should enable ultrasonic systems with 100 dB of dynamic range. A justification of the predicted dynamic range involves the careful consideration of the thermal noise limits of the system. Such analysis is developed and is based on the fluctuation dissipation theorem. In addition, the first scans produced with the new transducers are presented along with interpretations of their significant impact to nondestructive testing. Pictures of surface and bulk defects in composites and metals are included. Finally, the fabrication process is summarized and the issues involved in the development of immersion transducers are highlighted. [Work supported by the U.S. Office of Naval Research.]

from ASA 131st Meeting, Indianapolis, May 1996