【摘要】 本文叙述了合理确定极板尺寸的意义，描述了梯度线圈的计算方法和设计指标，给出了框式磁体和开放式Ｃ型磁体在典型气隙尺寸下梯度磁场线性度与梯度线圈外形尺寸关系的计算曲线，并讨论了一些因素对梯度线圈外形尺寸的影响，从而对磁体极板尺寸提出了要求。更多还原

【Abstract】 The designers of overall MRI system are interested in the selection of a rational pole size of permanent magnet so as to reduce both magnet weight and cost and satisfy technical requirement of linearity of gradient fields. In this paper calculation methods and technical requirements of gradient coils are described. The relationship between linearity of gradient field and sizes of magnet pole is given under the typical gap for frame type magnet and open C type magnet. The effect of some factors is discussed.更多还原