Patent ID: 7855355

Claim:
A high-voltage power unit capable of selectively providing a high voltage of positive or negative polarity, comprising: a positive voltage generating circuit with two output terminals for generating a positive high voltage; a negative voltage generating circuit with two output terminals for generating a negative high voltage; a control circuit for controlling each of the positive high voltage generated by the positive voltage generating circuit and the negative high voltage generated by the negative voltage generating circuit; a first resistor connected between the two output terminals of the positive voltage generating circuit in parallel to an output side of the positive voltage generating circuit; and a second resistor connected between the two output terminals of the negative voltage generating circuit in parallel to an output side of the negative voltage generating circuit, wherein: one output terminal of the positive voltage generating circuit and one output terminal of the negative voltage generating circuit are connected to connect the two voltage generating circuits in a series connection; one of two terminals of the series connection is used as a reference side, and a high-voltage output whose polarity is changed is taken out from the other terminal; and the first resistor and the second resistor are connected in a series connection.