The magnetic field distribution of a rectangular magnet is relatively simple, typically having two magnetic poles. Magnetic field lines originate from the north pole and return to the south pole, exhibiting a relatively regular linear distribution. The magnetic field strength is stronger in the regions near the poles and weakens rapidly further away.
Multipole magnets, on the other hand, have multiple magnetic poles, resulting in a more complex magnetic field distribution. For example, a common quadrupole magnet has two main north and south poles, as well as two intermediate poles. The magnetic field lines intertwine between the poles, forming a denser magnetic field region, and the magnetic field strength is also greater near the intermediate poles.
The magnetic field of multipole magnets can be controlled and adjusted more precisely, making them suitable for applications requiring high magnetic field accuracy, such as the focusing magnetic fields in some electronic devices. In contrast, the magnetic field of a rectangular magnet is relatively simple, while multipole magnets can generate more complex magnetic field patterns to meet different application needs.
