| 摘要 |
PURPOSE:To easily enter and retreat a patient in and from a coil for a unclear magnetic resonance imaging apparatus by removing capacitors disposed at the positions of approx. 90 deg. and 270 deg. from the power supply points of a pair of loop elements as starting points from the loop elements to be able to be separately to upward and downward. CONSTITUTION:When a high frequency current is supplied from a high frequency power source 16 to a power supply point 18 and the value of a capacitor 15 is properly selected to be resonated, a standing wave current is generated in a loop element 13. Since no current flows to the positions of approx. 90 deg. and 270 deg. as seen from the point 18, the capacitors 15 disposed at the positions may be removed without fail. The current of a segment 14 becomes '0' at the positions of 0 deg. and 180 deg., and even if the segment near the position of 180 deg. is removed, it does not affect the operation of an RF coil 11. A patient can be readily entered and retreated by removing the upper half of the coil 11. The diameter D of the coil 11 is formed in sufficient size to contain the partient's head, and its length l is selected to 0.1-1.5 times as large as the diameter D to eliminate the deterioration in the image of projecting due to the disturbance of a magnetic field at the end.
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