WO/2003/048789 is referenced by 3 patents.

An electrodynamic sensor comprises a high input impedance electrometer adapted to measure small electrical potentials originating from an object under test and having a pair of input probes, characterised in that at least one of said pair of input probes has no direct electrical contact with said object, wherein the circuit arrangement of said electrometer comprises an amplifier which includes a combination of ancillary circuits cumulatively to increase the sensitivity of said electrometer to said small electrical potentials whilst not perturbing the electrical field associated therewith.

Electrodynamic sensors and applications thereof
Application Number
Publication Number
Application Date
December 9, 2002
Publication Date
June 12, 2003
Harland Christopher J
Prance Robert J
Clark Terence D
MAGGS Michael Norman
Harland Christopher J
Prance Robert J
Clark Terence D
G01R 05/28
G01R 29/12
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