[Limited diffraction beams and its application].
Limited diffraction beams have a large depth of field and thus have many applications such as medical imaging, tissue characterization, material flaw detection and blood flow detection by Doppler method. Nondiffraction beams colud be produced only by transducer with an infinity large aperture in theory. The experimental results show that limited diffraction beams produced by a limited aperture have desirable large depth of field also. The theory of this kind of beams and their applications in field of medical imaging and blood flow estimation are introduced.
Cao
P
P
Xi'am Jiaotong University, Xi'an 710049.
Ma
D
D
Cheng
J
J
D000162:Acoustics; D003952:Diagnostic Imaging