Method and apparatus for contactless measurement of charge concentrations and potential differences in biological organisms

Claim 7

Apparatus for the contactless measurement of charge concentrations and potential differences in biological organisms, including: measuring electrode means for measuring charge concentrations; shield means for screening said electrode means and defining a window through which said electrode means is accessible to electrostatic fields; dielectric means in said window having a dielectric constant higher than air; said electrode means being one plate of a capacitor, the other plate of which is the surface of the organism to be measured; means for electrically connecting said electrode means to a reference potential; circuit means for measuring and/or indicating changes in charge on said electrode means resulting from relative movement of said electrode means with respect to said organism surface; and wherein said electrode means is centrally mounted within and insulated from said shield means, said electrode means communicating with said window and thereby means exposed to said electrostatic fields.

Claim 8

Apparatus for the contactless measurement of charge concentrations and potential differences in biological organisms, including: measuring electrode means for measuring charge concentrations; shield means for screening said electrode means and defining a window through which said electrode means is accessible to electrostatic fields; dielectric means in said window having a dielectric constant higher than air; said electrode means being one plate of a capacitor, the other plate of which is the surface of the organism to be measured; means for electrically connecting said electrode means to a reference potential; circuit means for measuring and/or indicating changes in charge on said electrode means resulting from relative movement of said electrode means with respect to said organism surface; and wherein said electrode means is centrally mounted within and insulated from said shield means, said electrode means communicating with said window and thereby means exposed to said electrostatic fields.

Claim 9

The apparatus of claim 4 wherein said circuit means includes: differential amplifier means for receiving signals from said electrode means; and meter means for displaying said signals.

Claim 10

The apparatus of claim 5, including: means for subdividing said signals from said electrode means into positive and negative signals; and means for logarithmically amplifying said positive and negative signals.

Claim 11

The apparatus of claim 4, including: acoustic signal means for generating acoustic signals commensurate with signals from said electrode means.

Claim 12

The apparatus of claim 4 including: guard electrode means, said electrode means and said organism surface forming a capacitor, and said first electrode means and said guard electrode means forming a second capacitor.

Claim 13

The apparatus of claim 8, including: means for moving said guard electrode relative to said electrode.

Claim 14

The apparatus of claim 9, wherein: said guard electrode surrounds said electrode and moves longitudinally with respect thereto.

Claim 15

The apparatus of claim 8, including: means for oscillating said electrode means relative to said guard electrode means.

Claim 16

The apparatus of claim 11 wherein: said electrode means is mounted on spring means, said spring means also being attached to piezoelectric means which generates signals in response to oscillation of said electrode means.

Claim 17

Apparatus for the contactless measurement of charge concentrations and potential differences in biological organisms, including: measuring electrode means for measuring charge concentrations; shield means for screening said electrode means and defining a window through which said electrode means is accessible to electrostatic fields; said electrode means being one plate of a capacitor, the other plate of which is the surface of the organism to be measured; means for electrically connecting said electrode means to a reference potential; and circuit means for measuring and/or indicating changes in charge on said electrode means resulting from relative movement of said electrode means with respect to said organism surface; means for periodically varying the dielectric field between said electrode means and said organism surface; and wherein said electrode means is centrally mounted within and insulated from said shield means, said electrode means communicating with said window and thereby being exposed to said electrostatic fields.

Claim 18

Apparatus for the contactless measurement of charge concentrations and potential differences in biological organisms, including: measuring electrode means for measuring charge concentrations; shield means for screening said electrode means and defining a window through which said electrode means is accessible to electrostatic fields; said electrode means being one plate of a capacitor, the other plate of which is the surface of the organism to be measured; means for electrically connecting said electrode means to a reference potential; and circuit means for measuring and/or indicating changes in charge on said electrode means resulting from relative movement of said electrode means with respect to said organism surface; means for periodically varying the dielectric field between said electrode means and said organism surface; and wherein said electrode means is centrally mounted within and insulated from said shield means, said electrode means communicating with said window and thereby being exposed to said electrostatic fields.

Claim 19

The apparatus of claim 13 wherein: said varying means includes means for moving a dielectric guard electrode between the surface of the organism and said electrode means.

Claim 20

The apparatus of claim 13 wherein: said varying means includes means for moving said electrode means relative to a dielectric guard electrode.

Claim 21

The apparatus of claim 13 including: liquid crystal means between said electrode means and said organism surface, and means for varying the polarization of said liquid crystal means.

Claim 22

The apparatus of claim 16 wherein: said electrode means is fixed to and insulated from said liquid crystal means.

Claim 25

The method of claim 18 wherein the step of moving a capacitor plate includes: guiding the measurement electrode over the surface of the organism at a substantially constant distance therefrom.

Claim 26

The method of claim 18 including: oscillating said measuring electrode to alternatively form capacitors between said electrode and said surface of the organism and between said measuring electrode and a guard electrode.

Claim 27

The method of claim 18 further including: periodically varying the dielectric constant of the capacitor formed between said measuring electrode and said surface of the organism.