Spatial decomposition of the ultrasonic echo using a tomographic approach. Part A: The regularization method

نویسندگان

  • Magnus Sandell
  • Anders Grennberg
چکیده

One of the most common methods for making images with ultrasound is to use the pulseecho method. The basic idea is to determine the time delay between different echoes from different points on the object. This method assumes that the echoes only differ in arrival time. If the shape of the echo is dependent on where on the surface it is reflected, this method can yield an inaccurate image. To be able to compensate for this or to extract information from the shape of the echo, it is crucial to know the characteristics of the transducer. One such characteristic is the single point echo (SPE), i.e. the echo from a point reflector. In this report, we propose a method to experimentally determine the SPE. The direct measurement of this echo is not possible due to practical problems and diffraction effects. We use a tomographic approach where we can determine the SPE from a series of measured echoes from sliding halfplanes.

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تاریخ انتشار 1993