flat field magnet

例句：

1. 1. The flat fieldmagnet is used to attract and focus magnetic fields.
   平坦场磁铁用于吸引和聚焦磁场。
2. 2.The flat field magnet was designed to improve the accuracy of magnetic readings.
   平坦场磁铁被设计用来提高磁读数的准确性。
3. 3.The flat field magnet has been found to be effective in various scientific experiments.
   平坦场磁铁在各种科学实验中被发现是有效的。