| 摘要 |
The invention relates to a radio-frequency coil (RF-coil) (19) for use in a magnetic-resonance imaging apparatus. The RF-coil comprises a number of parallel bar-shaped electric conductors (37), which are arranged at regular intervals on an imaginary cylinder (39) and which are surrounded by a radio-frequency shield (RF-shield) (49). The bar-shaped conductors surround a measuring volume (11) of the device and are interconnected at at least one of their end portions (41, 45) by means of an electric end conductor (43, 47) extending in a plane transverse to the bar-shaped conductors. According to the invention, a further electric end conductor (51, 53) is arranged near and parallel to the end conductor (43, 47), and said further end conductor is electrically connected to the RF-shield (49), preferably by means of a flange-shaped electric conductor (55, 57). The end conductor (43, 47) and the further end conductor (51, 53) together form an electrical transmission line. As a result, an unwanted electromagnetic field (b1), which is generated by the current in the end conductor (43, 47), is compensated for by an electromagnetic field (b2) generated by the current in the further end conductor (51, 53). Thus, the electromagnetic field of the end conductor (43, 47) does not lead to unwanted dissipation effects and temperature increases in the body of a patient present in the measuring volume (11).
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