Three-dimensional imaging system based on Fourier transform synthetic aperture focusing technique

Ultrasonics ◽  
1990 ◽  
Vol 28 (4) ◽  
pp. 241-255 ◽  
Author(s):  
K. Mayer ◽  
R. Marklein ◽  
K.J. Langenberg ◽  
T. Kreutter
2004 ◽  
Vol 12 (04) ◽  
pp. 571-585
Author(s):  
L. MEDINA ◽  
E. MORENO

An algorithm has been developed to implement synthetic aperture focusing technique for B-scan. This is made at a several transmitter/receiver locations to form a map of ultrasonic reflectivity on the insonified region, considering the path travelled by the ultrasonic pulse from the transducer to the target and back again. To reconstruct the image, a time domain beam-former is applied to the envelope of the detected signals. This method minimizes the side-lobe amplitude and the restriction of λ/2 distance between two adjacent transducer positions can be neglected without loosing image resolution. The present work is focused on the location of the in-homogeneities, caused by the presence of a phantom immersed in a water tank. The results are presented when the distance between two adjacent transducer positions are varied from 0.5λ to 2.5λ showing that the longitudinal resolution is not affected but the lateral resolution becomes poorer when the distance is about 2λ. The error in the longitudinal location of in-homogeneities is within the minimum detectable distance of the system, while the lateral location error is increased when the distance between any two adjacent transducer positions is larger than 1.5λ.


Sign in / Sign up

Export Citation Format

Share Document