Apparatus for generating field-free region, apparatus and method for nano magnetic particle image

An apparatus for imaging nano magnetic particles, comprising:

• a measurement head in which a through hole for accommodating a sample including the nano magnetic particles is formed and in which an excitation coil and a detection coil are installed;
• a field-free region generation unit for forming a field-free region, in which there is a weak magnetic field or no magnetic field, in a spacing area between identical magnetic poles that face each other;
• and
• a control unit for applying a signal to the excitation coil when the measurement head is placed within the spacing area of the field-free region generation unit, controlling the field-free region so as to move in the sample, and imaging 3D positional distribution of the nano magnetic particles included in the sample based on a detection signal output from the detection coil,
• wherein the field-free region generation unit includes a pair of rectangular-shaped magnets and a pair of magnet arrays, in each of which multiple small magnets are arranged.

A method for imaging nano magnetic particles, comprising:

• applying a signal to an excitation coil installed in a measurement head that accommodates a sample including the nano magnetic particles;
• and
• moving a field-free region, in which there is a weak magnetic field or no magnetic field and which is generated in a spacing area between identical magnetic poles facing each other, in a sample and imaging 3D positional distribution of the nano magnetic particles included in the sample based on a detection signal output from a detection coil of the measurement head,
• wherein the field-free region is generated by a pair of rectangular-shaped magnets and a pair of magnet arrays, in each of which multiple small magnets are arranged.