Patent ID: 6100694
Filing Date: 2000-08-08
Classification: G01R

Abstract:
A multiple tuned bird cage coil for providing a substantially uniform RF field in a cylindrical sample area of said coil and exhibiting at least two fundamental resonant frequencies comprising:a plurality of leg conductors disposed spaced from an axis; andat least three annular conductors disposed about said axis and coupled to said leg conductors to define said cylindrical sample area with said leg conductors, said annular conductors and said leg conductors defining a low pass bird cage coil sharing a portion of each of said leg conductors with a high pass bird cage coil such that a higher frequency current and a lower frequency current flow through said shared portion of each of said leg conductors to provide said substantially uniform RF field in said cylindrical sample area, wherein said high pass bird cage coil comprises a first and a second inner annular conductor each comprising a series of annular capacitances, said inner annular conductors being connected to each other by said shared portion of said leg conductors,said low pass bird cage coil comprising first and second outer annular conductors, each comprising a series of annular inductances, said outer annular conductors being connected to each other by said leg conductors, said leg conductors comprising said shared portion of said leg conductors and a leg capacitance, said shared portion of said leg conductor comprising a leg inductance, whereby said higher resonant frequency and said lower resonant frequency are independently tuned.