Method and the system in order to collect the information regarding the object which includes the single magnetic domain particle are stated. Such single magnetic domain particle has the diameter of the range of approximately 5nm - 80nm. The method of collecting information, at the frequency which makes the electron paramagnetic resonance of occurrence and the single magnetic domain particle cause of magnetostatic field under approximately 0.1 Tesla who are impressed in the object, includes with the generation of RF energy of the pulse or continuous wave. The said method electron paramagnetic resonance of the single magnetic domain particle includes the fact that it detects with form of the picture of the object. As a substitution, the single magnetic domain particle may possess specified diameter and specified saturation magnetization, as for the magnetic field where it is impressed, the single magnetic domain particle at least approximately 10% of saturation magnetization, desirably, is possible to arrive in magnetization above that. With other execution form, as for principle of this invention, it detects the tag in the object, it is used in order to activate the tag.単磁区粒子を含む物体に関する情報を収集するための方法およびシステムが記載される。こうした単磁区粒子は、約5nm~80nmの範囲の直径を有する。情報を収集する方法は、物体に印加される約0.1テスラ未満の静磁場の発生と、単磁区粒子の電子常磁性共鳴を生じさせる周波数で、パルスまたは連続波のRFエネルギーの発生とを含む。該方法は、単磁区粒子の電子常磁性共鳴を物体の画像の形態で検出することを含む。代替として、単磁区粒子は、所定の直径および所定の飽和磁化を有してもよく、印加された磁場は、単磁区粒子が飽和磁化の少なくとも約10%、好ましくはそれ以上の磁化に到達するようにしてもよい。他の実施形態では、本発明の原理は、物体中のタグを検出し、タグを活性化するために用いられる。
