| 摘要 |
PROBLEM TO BE SOLVED: To provide a surface electric potential detection device which can easily adjust an offset that a surface electric potential detection output signal has. SOLUTION: A surface electric potential sensor 11 and a signal processing circuit 3 operate having the electric potential of a common ground line C. GND as their reference potential. A 1st bias circuit 36 includes in a signal processing circuit 3 applies a positive voltage (+V3) based upon the electric potential of the common ground line C. GND to the uninverted input terminal of an integrating circuit 32 to make the surface electric potential detection output signal Z have generate a positive offset voltage. A 2nd bias circuit 39 supplies a surface electric potential detection output circuit 35 with a negative voltage (-V5) cancelling the offset voltage generated by the 1st bias circuit 36. |
