In a convex array, each crystal is about ________ in width.

In a convex array, each crystal is about ________ in width.

• A. 1/4 wavelength
• B. 1/2 wavelength
• C. 1 wavelength
• D. 2 wavelengths

Answer: (C)

In a convex ultrasound array, the element width is typically about one wavelength. This size lets each crystal efficiently radiate and receive at the center frequency while providing a practical curved aperture for focusing. If the element is much smaller than a wavelength, you’d need many elements to cover the same aperture, reducing sensitivity and making fabrication more challenging. If it’s much wider than a wavelength, the aperture sampling becomes coarse, which can increase sidelobes and degrade beam quality and bandwidth. So, about one wavelength strikes a helpful balance for good beam shape and practical design.

In a convex ultrasound array, the element width is typically about one wavelength. This size lets each crystal efficiently radiate and receive at the center frequency while providing a practical curved aperture for focusing. If the element is much smaller than a wavelength, you’d need many elements to cover the same aperture, reducing sensitivity and making fabrication more challenging. If it’s much wider than a wavelength, the aperture sampling becomes coarse, which can increase sidelobes and degrade beam quality and bandwidth. So, about one wavelength strikes a helpful balance for good beam shape and practical design.