Cone-shaped micro coil for magnetic resonance imaging

This paper reports on a cone-shaped micro coil for measuring an NMR (Nuclear Magnetic Resonance) signal of an MRI (Magnetic Resonance Imaging). A three dimensional cone-shaped micro coil was fabricated by pulling up an outer frame of a spiral patterned micro coil. Since there are supporting parts between the wiring, the cone-shaped micro coil has uniform pitch. By using this process, we fabricated the cone-shaped micro coil of 30 mm in diameter and 8 mm in height. The resistance and Q-factor of the coil were 2.14 Ω and 32.3 at 8.5 MHz. As a demonstration of MRI by the cone-shaped micro coil, we acquired MR images of a quail egg and an okra.