Patent ID: 7986104

Claim:
A discharge lamp lighting apparatus comprising: a first inverter configured to invert DC source power into high-frequency power; a second inverter configured to invert the DC source power into high-frequency power whose phase is opposite to that provided by the first inverter; a discharge lamp connected between a first output terminal of the first inverter and a first output terminal of the second inverter; a first current detection circuit arranged between a second output terminal of the first inverter and a common potential and having a first current detection element and a second current detection element that are connected in series; a second current detection circuit arranged between a second output terminal of the second inverter and the common potential and having a third current detection element and a fourth current detection element that are connected in series; and a protection circuit commonly connected to a connection point where the first and second current detection elements are connected to each other and a connection point where the third and fourth current detection elements are connected to each other, the protection circuit being configured to detect a current abnormality according to a composite signal of outputs of the second and fourth current detection elements and make the operation of the first and second inverters inoperative.