Field generator and a nuclear magnetic resonance device equipped with this magnetic field generator

Providing a nuclear magnetic resonance apparatus having a more concise structure constituted by a magnetic circuit of an open magnetic circuit capable of generating a uniform magnetic field magnetic field generator and the magnetic field generator. With directing the direction of magnetization in the reference direction, between a first permanent magnet which are sequentially arranged at a predetermined interval in the reference direction and the second permanent magnets, a first permanent magnet and the second permanent magnet in, along the reference direction and a third permanent magnet and the fourth permanent magnet sequentially arranged at or a predetermined distance in contact with each other, the direction of magnetization of the third permanent magnet is parallel to the reference direction a first component, such, orthogonal to the first direction and a direction and a second component toward the region side, the direction of magnetization of the fourth permanent magnet includes a first component, a direction of the second component and opposite an open magnetic circuit type magnetic field generator was direction having an inverting second component was the same size as the second component.