Characterising the Effects of the External Electromagnetic Shield on a Magnetic Induction Tomography Sensor

A J Peyton1, S Watson2, R J Williams2, H Griffiths3 and W Gough4

1 Engineering Department, Lancaster University, Lancaster LA1 4YR, UK, a.peyton@lancaster.ac.uk

2 School of Electronics, University of Glamorgan, Pontypridd CF37 1DL, UK, swatson1@glam.ac.uk

3 Department of Medical Physics and Clinical Engineering, Singleton Hospital, Swansea SA2 8QA, UK, Huw.Griffiths@swansea-tr.wales.nhs.uk

4 Department of Physics & Astronomy, Cardiff University, CF2 3YB, GoughW@cf.ac.uk

ABSTRACT

The paper considers the effect of the outer conductive shield on an experimental MIT system and reports the results of a set of 3D finite element simulations of different screen dimensions. In particular, the effects of the diameter and height of the shield on the sensitivity maps and background signals are addressed. The simulations are compared with measurements taken from the actual sensor array. Finally, the paper concludes with some general observation and recommendations drawn from this case study, which will aid other researchers developing high frequency MIT systems.

Keywords Tomography, Electromagnetic, Mutual inductance, Screen.