A design of permanent magnet array for unilateral NMR device

Hirokazu Kato, Kanji Kishi, Norio Takahashi, Jun-Ichi Asaumi, Yasutoshi Honda, Yoshinobu Yanagi, Masaaki Aoki

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

We have designed a three-dimensional magnetic circuit consisting of various pieces of magnetic blocks for a unilateral MRI device, which generates a homogeneous magnetic flux density at a remote region. The direction of the remanent flux density of the main outer magnetic blocks is parallel to the surface of the device; hence the direction of the magnetic flux density in the remote region is also parallel to the surface of the device. The magnitudes of the remanent flux density of the magnetic blocks are adjusted so as to minimize the variation of the magnetic flux density in the remote region. This magnetic circuit, with an outer dimension of 400 mm x 400 mm x 200 mm, produces a magnetic flux density in a 20 mm x 20 mm x 5 mm region of interest at a distance of 55 mm from the surface of the device with a magnitude of 64.5 mT (2.75 MHz in resonant frequency) and a uniformity of 275 ppm (755 Hz in band width).

Original languageEnglish
Pages (from-to)201-208
Number of pages8
JournalConcepts in Magnetic Resonance Part B: Magnetic Resonance Engineering
Volume33
Issue number3
DOIs
Publication statusPublished - Aug 2008

Fingerprint

Magnets
Magnetic flux
permanent magnets
Permanent magnets
flux density
remote regions
Nuclear magnetic resonance
Equipment and Supplies
nuclear magnetic resonance
Magnetic circuits
magnetic flux
magnetic circuits
Fluxes
Magnetic resonance imaging
Natural frequencies
Bandwidth
resonant frequencies
bandwidth
Direction compound

Keywords

  • Magnetic circuit
  • Magnetic flux density
  • Permanent magnet
  • Uniformity
  • Unilateral NMR

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Spectroscopy
  • Radiology Nuclear Medicine and imaging
  • Radiological and Ultrasound Technology

Cite this

A design of permanent magnet array for unilateral NMR device. / Kato, Hirokazu; Kishi, Kanji; Takahashi, Norio; Asaumi, Jun-Ichi; Honda, Yasutoshi; Yanagi, Yoshinobu; Aoki, Masaaki.

In: Concepts in Magnetic Resonance Part B: Magnetic Resonance Engineering, Vol. 33, No. 3, 08.2008, p. 201-208.

Research output: Contribution to journalArticle

Kato, Hirokazu ; Kishi, Kanji ; Takahashi, Norio ; Asaumi, Jun-Ichi ; Honda, Yasutoshi ; Yanagi, Yoshinobu ; Aoki, Masaaki. / A design of permanent magnet array for unilateral NMR device. In: Concepts in Magnetic Resonance Part B: Magnetic Resonance Engineering. 2008 ; Vol. 33, No. 3. pp. 201-208.
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