With linear phased arrays the sound beam created by this more curved electrical pattern will have a _______ focus.

With linear phased arrays the sound beam created by this more curved electrical pattern will have a _______ focus.

• A. Shallower
• B. Deeper
• C. The Same
• D. Variable

Answer: (A)

The main idea here is how the curvature of the electrical excitation across the linear array shapes where the beam comes to a focus. A more curved pattern means the wavefront is more strongly convergent, which gives the beam a smaller radius of curvature. In practice, that tighter convergence makes the beam come to a focus closer to the transducer—that is, a shallower focus. If you reduce the curvature, the wavefront is flatter and the focus moves deeper away from the transducer.

The main idea here is how the curvature of the electrical excitation across the linear array shapes where the beam comes to a focus. A more curved pattern means the wavefront is more strongly convergent, which gives the beam a smaller radius of curvature. In practice, that tighter convergence makes the beam come to a focus closer to the transducer—that is, a shallower focus. If you reduce the curvature, the wavefront is flatter and the focus moves deeper away from the transducer.