| 摘要 |
A control unit (5) controls an operation of an electric power conversion unit (4) so that load current that flows through a light source load (200) becomes a constant value, using electric power setting value that is used to determine a size of electric power that is supplied to the light source load and a current detection value that is detected by a current detection resistor (45), and a load electric power calculation unit (9, 90) obtains load electric power of the light source load using the electric power setting value and a voltage detection value that is detected by a voltage detection unit (6), and an input electric power estimation unit (91) corrects a circuit loss for the obtained load electric power and estimates input electric power. |
