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A Study of Near Field Ultrasonic Beam Patterns from a Pulsed Linear Array

  • E. B. Miller
  • S. W. Smith
  • F. L. Thurstone

Abstract

A major advantage of pulse-echo imaging in the near-field of an acoustic array is the improved lateral resolution that focusing makes possible. Usually, equivalence is tacitly assumed between a lateral beam dimension for continuous wave excitation and a lateral pulse dimension for the same geometry. Although distinctions certainly exist between the lateral dimensions in these two cases, it is convenient in dealing with pulsed ultrasound to speak of a “beam” or “beams” of ultrasonic energy. By analogy to the continuous wave case, such a beam may be defined as the envelope of a pulse dimension. This dimension may be specified by some absolute or r.m.s. pressure magnitude criterion (e.g., the distance to a point at which the absolute pressure is down “n” dB from the maximum value in the field).

Keywords

Pressure Field Pulse Length Line Source Lateral Resolution Array Element 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1974

Authors and Affiliations

  • E. B. Miller
    • 1
  • S. W. Smith
    • 1
  • F. L. Thurstone
    • 1
  1. 1.Department of Biomedical EngineeringDuke UniversityDurhamUSA

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