High voltage power source for a discharge tube

摘要

A high voltage power source for supplying a DC high voltage to a discharge tube, can detect an abnormality when created at the discharge tube side and stop its output. The high voltage power source is provided with a detector circuit which detects when the DC high voltage is larger than a predetermined reference value and a control circuit which cuts off the output of the DC high voltage in response to the above detection. When an abnormality occurs at the discharge tube, for example, non-operation or unstable operation occurs, since a load becomes lighter than normal, and the DC high voltage to be supplied to the discharge tube becomes higher than normal and is detected by the detector circuit so that the control circuit responds to the detected high voltage and cuts off the output of the DC high voltage.