# What is synthetic aperture focusing technique?

## What is synthetic aperture focusing technique?

SAFT – Synthetic Aperture Focusing Technique – is a signal processing technique which takes advantage of the movement of a small conventional transducer to simulate, in effect, a phased array that is extremely long. This allows high resolution at long range, with relatively small transducers.

What is synthetic focusing?

The synthetic focusing improves the lateral resolution of an ultrasonic image without use the traditional ultrasonic lenses. SAFT simulates a focused transducer, improving the lateral resolution by calculating the relation between the signals of N transducers disposed in line (multiple transducer).

### What is synthetic aperture focusing (Saft)?

Kreutter, K.Mayer and V. Schmitz The synthetic aperture focusing technique (SAFT) is briefly reviewed and addressed as a heuristic digital ultrasonic imaging scheme which exploits the idea of backpropagating a set of measured and digitally stored A-scans.

What is the synthetic focus?

The synthetic focus is based on the geometrical reflection or ray acoustic model [1-3]. In this model the focus of the ultrasonic transducer is assumed to be a point of constant phase which all the sound rays pass through before diverging in a cone whose angle is determined by the diameter of the transducer and the focal length.

#### What is the Saft technique?

The technique known as SAFT use this equation to eliminate or at least minimize the effects of the transducer aperture beam width over an B-scan or C-scan image. To use this technique we need to calculate, for each image line the position where the signal should be inside an adjacent line and thereafter a correlation has to be made.

How to obtain one-to-one image with respect to the aperture coordinate?

To obtain a one-to-one image with respect to the aperture coordinate we choose Ax’ = 0.3048 mm = Az’ yielding OK, = AK, = 0.081 mm-‘ for 256 X 256 pixel points.