Image Distortion and Point Response of the Ultrasonic Echogram

Abstract

Point response and image distortion of ultrasonic diagnostic system are investigated. The echogram for a thin wire target is shaped like a letter T. The horizontal or transversal bar is originated from directivity of the ultrasonic beam, and the vertical or axial bar multireflection effect in the target. If the targets are in the second medium, ultrasonic beam will be deflected at the boundary of the first and the second media. Snell's law of optics can be applied to calculate the displacement of the image of the targets. Experiments and calculations show fairly good agreement.