Theoretical Study of Pulsed Echographic Focusing Procedures
This paper is devoted to a theoretical evaluation of the pulsed echographic response of spherical focusing apertures used in B-scan imagery. Loss-less as well as absorbing medium are investigated. The effects of transducer bandwidth on lateral resolution and side lobe level is studied. The differences observed between the pressure pattern and the complete echographic response pattern is emphasized for well damped and for narrow-band transducers. The influence of a frequency dependant attenuation on these patterns is shown, and an explanation of the defocusing process observed in biological medium [l] is given.
KeywordsImpulse Response Velocity Potential Convolution Product Pulse ECHOGRAPHIC Side Lobe Level
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