ISSN:
1741-0444
Keywords:
Air-borne ultrasound
;
Anthropometry
;
Electrostatic transducers
;
Remote measurement
;
Ultrasound scanner
;
Ultrasound transducers
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
Notes:
Abstract Remote measurement of distance, direction, size, form and volume are common but intricate measurement problems. We have applied the ultrasound pulse echo method, well-known from diagnostic ultrasound, for remote measurement in air. Short ultrasound pulses are emitted in air by electric excitation of an ultrasound transducer. When the ultrasonic wave is incident on a boundary between media of different acoustic impedance, part is reflected back as an echo. The time delay between transmission of the ultrasound pulse and the reception of an echo is a measure of the distance between the transducer and the echo-generating structure. The information obtained can be processed in different ways to produce the three main types of display: A-mode, B-mode and TM-mode. As a consequence most methods from diagnostic ultrasound can be applied also for ultrasound in air. Examples are given of biomedical applications, including a real-time ultrasound scanner for use in air.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02442811
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