Which imaging technique most directly increases the field of view for a linear array?

Which imaging technique most directly increases the field of view for a linear array?

• A. Elevational focusing
• B. Trapezoidal scanning
• C. Increasing frequency
• D. Increasing damping

Answer: (B)

The key idea is how scanning geometry controls how wide the image appears across the sides. Trapezoidal scanning widens the effective beam aperture as depth increases, so the transmitted and received beams fan out more with depth. That makes the lateral extent of the image grow, producing a wider field of view and a trapezoid-shaped footprint in the image. Elevational focusing changes the beam thickness in the elevational (out-of-plane) direction, not the width of the image in the imaging plane. Increasing frequency improves resolution and penetration trade-offs but doesn’t widen the field of view. Increasing damping affects signal amplitude and spectral content rather than the beam footprint.

The key idea is how scanning geometry controls how wide the image appears across the sides. Trapezoidal scanning widens the effective beam aperture as depth increases, so the transmitted and received beams fan out more with depth. That makes the lateral extent of the image grow, producing a wider field of view and a trapezoid-shaped footprint in the image. Elevational focusing changes the beam thickness in the elevational (out-of-plane) direction, not the width of the image in the imaging plane. Increasing frequency improves resolution and penetration trade-offs but doesn’t widen the field of view. Increasing damping affects signal amplitude and spectral content rather than the beam footprint.