An Electronically Focused Acoustic Imaging Device
We describe in this paper a new technique for processing acoustic information from a piezoelectric array. The device we shall describe is capable of presenting dynamic, nearly real time images of acoustic objects whether they be internal body organs in medical applications, wreakage in the sea, or flaws in nondestructive testing. The present device is capable of 1 mm resolution at distances of 20 cm and operates without the use of an external focusing element or an intermediary hologram. In the experimental results reported here two dimensional images are obtained using electronic scanning in one dimension and mechanical scanning in the other dimension. We will describe near the end of this paper how a fully electronic two dimensional scan may be implemented. The sensitivity of the imaging apparatus is expected to be sufficient to insure low sound power levels while still obtaining high quality images.
KeywordsSurface Wave Delay Line Acoustic Image Chirp Rate Acoustic Lens
Unable to display preview. Download preview PDF.
- 2.W.H. Wells, “Acoustic Imaging with Linear Transducer Arrays”, in Acoustical Holography, Vol. 2, Plenum Press, (1970).Google Scholar
- 3.N. Takagi, et al., “Solid State Acoustic Image Sensor”, in Acoustical Holography, Vol. 4, Plen um Press, (1972).Google Scholar
- 4.R.W. Wood, Physical Optics, Dover Publications, (1934).Google Scholar
- 5.J.W. Goodman, Introduction to Fourier Optics, McGrawHill, (1968).Google Scholar
- 6.op. cit.Google Scholar