US Patent 7722602 Electrosurgical device

An electrosurgical device is provided which can prevent the decrease of the effect of a treatment performed by an operator or the like on a biological tissue. A high-frequency voltage generated in an alternating power supply is transformed in a transformer. A high-frequency current in accordance with the transformed high-frequency voltage is supplied to the biological tissue via two high-frequency current supply lines. In this case, the impedance between the two high-frequency current supply lines is set in an impedance matching circuit so as to become maximum with respect to the frequency of the high-frequency current. Accordingly, the decrease of the effect of the treatment performed on the biological tissue can be prevented.