Acoustic Imaging with Thin Annular Apertures
It was shown in a previous analysis that a mosaic of piezoelectric acoustic detectors would be sensitive enough to image tissue structures deep within the body and would be able to resolve details as small as one millimeter1. We will discuss here a method of achieving the effect of a full piezoelectric aperture without having to build one. The basic idea is that if we measure the amplitude and phase of a wave-front on the annulus bounding an aperture, it is possible to use these measurements to produce an image of the object producing that wave front Moreover, the resolution of the image produced by an annulus around an aperture will equal the resolution produced by the full aperture.
KeywordsPoint Source Bessel Function Object Plane Point Response Speckle Noise
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