The near field (Fresnel zone) is the region of the ultrasound beam closest to the transducer face, where the beam remains relatively narrow and parallel. Beam intensity is somewhat irregular in the near field due to interference between wavefronts from different parts of the transducer. Very superficial structures in the near field may be difficult to image well, which is why a standoff pad or generous amounts of gel are sometimes used to move structures into a more favorable imaging depth.