| 摘要 |
<p>PURPOSE: To avoid a decline of Q-factor by introducing a variable capacitor, tuning a ground braker circuit, and making smaller an assembly mountable directly on an RF-coil. CONSTITUTION: The outside conductor of a coaxial connector 202 to both for securing a good connection to RF between a conductor's lead wires 250, 254 of a circuit in the upper and lower surfaces is soldered corresponding to a print circuit substrate 200. A coil 102 is made of the outside conductor of a coaxial cable coiled. The conductor ends 270, 272 of the outside cable to the conductor's lead wires 250, 252 of the print circuit are soldered, on the other hand, also soldering a projected internal conductor to an internal conductor of the coaxial cable 202, 204. The ground braker is a parallel resonance LC circuit composed on the print circuit substrate 200, then sufficiently smaller and rigid in an extent to be mountable directly on the RF coil structure of MRI-system by using the variable capacitor for tuning. Accordingly, the decline of Q-factor can be avoided as the ground braker can be moved in synchronization with the movement of the RF coil structure.</p> |
