Diffraction Artefacts and their Removal
Gore and Leeman (1977) verified experimentally for the medical ultrasound case, in the context of the ‘replica pulse’ formulation of Freedman (1961), that the transient pressure field produced by a piston-like transducer can be described as a sum of two major components: ‘direct’ and ‘edge’ waves (Weight and Hayman, 1978). The edge waves are produced by the periphery of the transducer and are the cause of the diffraction effects observed in many measurement and calibration schemes based on techniques using small hydrophones to probe pulsed ultrasound fields.
KeywordsAmplitude Spectrum Edge Wave Acoustical Image Reflectivity Function Ultrasound Field
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