Lateral resolution improves with higher frequencies because, in the far field, higher frequency pulses diverge less than low frequency ones.

Lateral resolution improves with higher frequencies because, in the far field, higher frequency pulses diverge less than low frequency ones.

• A. More
• B. Less
• C. The same
• D. Random

Answer: (B)

Lateral resolution depends on how wide the beam is as it travels—the narrower the beam, the better the ability to distinguish side-to-side details. In the far field, diffraction causes the beam to spread, and this spreading is tied to the wavelength. Since frequency and wavelength are inversely related, higher frequency gives a shorter wavelength, which reduces diffraction and keeps the beam tighter as it propagates. That narrower beam translates to improved lateral resolution. So the divergence is less at higher frequencies, making the correct completion “Less.” Higher frequency would not cause more spreading or the same amount of spreading, and it isn’t random.

Lateral resolution depends on how wide the beam is as it travels—the narrower the beam, the better the ability to distinguish side-to-side details. In the far field, diffraction causes the beam to spread, and this spreading is tied to the wavelength. Since frequency and wavelength are inversely related, higher frequency gives a shorter wavelength, which reduces diffraction and keeps the beam tighter as it propagates. That narrower beam translates to improved lateral resolution. So the divergence is less at higher frequencies, making the correct completion “Less.” Higher frequency would not cause more spreading or the same amount of spreading, and it isn’t random.