Abstract: The invention provides a method and apparatus for the detection of charge density distribution at the surface of a material sample. The apparatus comprises an electric potential sensor for measuring surface charge on a material sample, wherein the electrical potential sensor includes a probe for capacitively coupling the electric potential sensor to the surface of the material sample, an amplifier for generating a measurement output, the probe being connected to an input of the amplifier and the measurement output being supplied at an output of the amplifier, and a feedback arrangement driven from the output of the amplifier for enhancing the input impedance of the amplifier.
Type:
Grant
Filed:
June 20, 2011
Date of Patent:
August 5, 2014
Assignee:
The University of Sussex-Falmer
Inventors:
Helen Prance, Robert John Prance, Philip Watson, Sam Thomas Beardsmore-Rust