(Woods Hole Oceanographic Institution, 1985-02)
Sato, Tomamasa; Jaffe, Jules S.
This paper describes the underwater imaging method of "Synthetic Aperture
Image Holography" which has real-time imaging capability. This method
utilizes image holography and computer synthetic aperture techniques. The
imaging system consists of the acoustic lens, ultrasound receiving and
transmitting arrays, and the computer. The diameter of the acoustic lens is
smaller than the aperture of the transmitting array. By transmitting the
ultrasound from the elements of the transmitting array one by one, the phase
and amplitude of the lower resolution images (image holograms), focused by the
acoustic lens, are detected by the receiving array. After obtaining all of
the image holograms, the final image is calculated by synthesizing all of
these image holograms in the computer. The results of one-dimensional
underwater experiments are shown. The conceptual design of a real-time
imaging system that is based on this method is also presented.
