Acoustic Echo Computer Tomography
Acoustic tomography systems described in the past were designed to provide a cross-sectional image of an object by employing transmission of a beam of ultrasonic energy. The data thus obtained were processed by a computer using a suitable algorithm. This resulted in an image based upon either the acoustic velocity or the attenuation characterisic of the object. This paper describes two novel imaging techniques which are based on the reflection of acoustic waves from the distribution of scattering centers within the object. One of the primary advantages envisioned for the proposed techniques is the use of a single collimated beam of ultrasound in the plane of the tomogram in lieu of slow mechanical scanning or multiple transducer arrays. Results are presented of a laboratory experiment which was performed to test the validity of one of the proposed concepts.
KeywordsAcoustic Velocity Line Integral Acoustical Holography Differential Travel Time Rear Half
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