Beam steering is a method of steering the main lobe of a transducer to a certain direction. Array transducers have the ability to be steered as well as focused. Like focusing, the beam is directed by sequentially stimulation of each element. This feature creates the sector scan by rapidly steering the beam from left to right to give the two dimensional cross sectional image.

The main lobe is the main acoustic transducer beam. There are other, smaller lobes called side lobes that are located around the main lobe.

See also Side Lobe, Grating-lobe Artifact, Beam Steering, Beamforming.

(short for ultrasound beam) The sound beam is the confined, directional beam of ultrasound traveling as a longitudinal wave from the transducer face into the propagation medium. The near field and the far field are two separate regions along the beam. Sound beams are either steered mechanically or electrically. Both rapidly sweep sound waves through tissues.

See also Sheer Wave, Beam Vessel Angle, Beam Steering, and Huygens Principle.