Active probe and method for measurement of space charge distribution of polymer

An active probe for measuring space charge distribution of a polymer, the active probe comprising a case, a signal-extracting aluminum block, a quartz glass block, a piezoelectric ceramic sheet, an electric pulse transmission unit and a measured signal extraction unit, an outer surface of the quartz glass block is adhered with a conductive material in contact with the case, an anode of the piezoelectric ceramic sheet is connected to the electric pulse transmission unit, and a cathode of the piezoelectric ceramic sheet is connected to the conductive material on the outer surface of the quartz glass block, and the signal-extracting aluminum block is respectively connected with the quartz glass block and the measured signal extraction unit;

• wherein an annular groove is located at a bottom of the case and is located in a connecting surface of the quartz glass block, the annular groove is located at an outer side of the piezoelectric ceramic sheet, and the annular groove is filled with soft metal, a thickness of the soft metal is larger than a depth of the annular groove.