摘要:
Quadrature coils for magnetic resonance imaging (MRI apparatus) are in the form of loops constructed of foil bands of conductive material with their respective axes forming an angle with each other to provide the quadrature phase signals. Trapezoidal cutouts are in each loop to allow for entry of the head of a human being or other large specimen. The angle between the coils is adjusted to compensate for the cutouts to provide and maintain the quadrature phase signals. Inductive coupling between the coils is minimized by three rectangular trim foils which are parallel to the main magnetic field and placed adjacent to the coils.