Which image format results when each pulse originates from the same starting point and uses electronic focusing and beam steering?

• A. Sector
• B. B-Mode
• C. Linear Array
• D. 3D Scan

Answer: (A)

Sector imaging occurs when the transmitted beam is steered electronically from a single starting point on the transducer face. A phased or electronic array uses coordinated delays across the elements to both steer the beam and focus it at different depths. Since all pulses originate from that same point and are swept through angles, the resulting field is wedge-shaped, producing a sector image. This is in contrast to a linear array, which scans with parallel lines to form a rectangular field, or a 3D scan, which builds a volumetric dataset, or B-mode, which refers to the gray-scale display rather than the scan geometry.