| 摘要 |
<P>PROBLEM TO BE SOLVED: To perform calculation of shimming in a short time even if the number of channels of a transmission coil increases. <P>SOLUTION: This magnetic resonance apparatus changes a pattern of a signal supplied to the transmission coil, and obtains transmission magnetic field distributions B1<SB POS="POST">2π/8</SB>-B1<SB POS="POST">16π/8</SB>in each pattern of the signal. The magnetic resonance apparatus selects the transmission magnetic field distribution B1<SB POS="POST">2π/8</SB>having highest uniformity of a magnetic field and the transmission magnetic field distribution B1<SB POS="POST">10π/8</SB>having weakest correlation with the transmission magnetic field distribution B1<SB POS="POST">2π/8</SB>from 8 transmission magnetic field distributions B1<SB POS="POST">2π/8</SB>-B1<SB POS="POST">16π/8</SB>. Next, the magnetic resonance apparatus obtains a composite transmission magnetic field distribution B1<SB POS="POST">comb</SB>(amp, θ) between the transmission magnetic field distribution B1<SB POS="POST">2π/8</SB>and the transmission magnetic field distribution B1<SB POS="POST">10π/8</SB>, and determines a combination between an amplitude amp and a phase θ when the composite transmission magnetic field distribution B1<SB POS="POST">comb</SB>(amp, θ) becomes most uniform. <P>COPYRIGHT: (C)2013,JPO&INPIT |
