Which array transducer fires all of the elements for each acoustic scan line, using small time delays to steer the beam?

Which array transducer fires all of the elements for each acoustic scan line, using small time delays to steer the beam?

• A. Linear segmental array
• B. Convex array
• C. Annular array
• D. Phased array

Answer: (D)

Electronic beam steering is achieved when all elements of a transducer array fire for each scan line and small, precise time delays are applied to the element excitations. Those delays cause the emitted waves to interfere constructively in a chosen direction, steering the beam without moving the probe. That ability to use the entire array with adjustable delays for each line is the defining feature of a phased array. Other array types differ in how they form or steer the beam. A linear segmental array uses separate segments activated in sequence to create each line, rather than steering the whole, fully active array with delays. A convex array is a curved version of a linear array and typically relies on its fixed focusing pattern rather than line-by-line electronic steering across angles. An annular array uses concentric rings and focuses via delays to a focal point, not by steering the beam across angles for each scan line.

Electronic beam steering is achieved when all elements of a transducer array fire for each scan line and small, precise time delays are applied to the element excitations. Those delays cause the emitted waves to interfere constructively in a chosen direction, steering the beam without moving the probe. That ability to use the entire array with adjustable delays for each line is the defining feature of a phased array.

Other array types differ in how they form or steer the beam. A linear segmental array uses separate segments activated in sequence to create each line, rather than steering the whole, fully active array with delays. A convex array is a curved version of a linear array and typically relies on its fixed focusing pattern rather than line-by-line electronic steering across angles. An annular array uses concentric rings and focuses via delays to a focal point, not by steering the beam across angles for each scan line.