Ultrasound transducers that produce images via linear array typically contain 256-512 elements, making them the largest assembly. Each element produces a scan line that makes up the ultrasound image.
Multiple adjacent elements combine to produce an ultrasound beam that is emitted at 90 degrees to the transducer head. Multiple elements (5 to 20) work as an individual unit in order to achieve a wider aperture and more useful beam shape. The ultrasound beam produced moves sequentially along the transducer one element at a time to obtain the image. Received ultrasound echoes are interpreted as corresponding to the centre element of the beam.
Linear transducers produce a rectangular field of view with uniform beam density throughout. They are useful for imaging shallow structures and small parts.