Method and apparatus for measuring the electrical conductivity of a subject

Apparatus for measuring the electrical conductivity of a subject comprising:

• magnetic field producing means for producing a substantially uniform magnetic field within a predetermined volume;
• motive means for causing relative movement between said subject and said predetermined volume so as to move at least portions of said subject into and out of said volume;
• measuring means coupled with said magnetic field producing means for measuring substantially only the electrical conductivity thereacross;
• and control circuit means for causing said measuring means to measure the electrical conductivity across said field producing means a plurality of times during movement of said subject relative to said volume so as to obtain a plurality of measurements of the electrical conductivity across said magnetic field producing means with different portions of said subject within said volume.

A method for measuring the electrical conductivity of a subject comprising:

• providing a chamber having at least one open end for receiving said subject therein;
• producing a substantially uniform magnetic field within said chamber;
• causing relative movement between said subject and said chamber so as to move said subject into and out of said chamber;
• measuring substantially only the electrical conductivity across said magnetic field a plurality of times while said subject is being moved at least one of the directions into and out of said chamber so as to obtain a plurality of measurements of the electrical conductivity across said magnetic field with said subject in said chamber to a plurality of different extents.

Apparatus for measuring the electrical conductivity of a subject comprising:

• a chamber having at least one open end for receiving said subject therein;
• magnetic field producing means for producing a substantially uniform magnetic field within said chamber;
• and measuring circuit means electrically coupled with said magnetic field producing means for measuring substantially only the electrical conductivity thereacross;
• wherein said measuring circuit means comprises phase detector circuit means coupled with said magnetic field producing means for developing a conductivity signal representative of the conductivity across said magnetic field producing means including the reflected conductivity of any portion of said subject located inside of said magnetic field producing means, and amplitude detector circuit means also coupled with said magnetic field producing means for developing an amplitude signal representative of the amplitude of the electrical admittance across said magnetic field producing means.