| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a lighting device which can suppress a rise of its temperature by reducing circuit loss and keep lighting, even where it is used with a plurality of power sources whose power source voltages are different from each other, and provide a luminaire using the lighting device. <P>SOLUTION: A lighting device comprises a first converter unit 2, a second converter unit 3, and a control unit 4 for controlling the first converter unit 2 and the second converter unit 3. The control unit 4 includes: a power source voltage detection portion 45 for detecting an output voltage of an input power source; and a lamp voltage detection portion 42 for detecting a lamp voltage V2 applied to a high-pressure discharge lamp 100, and performs: a setting control for setting an input voltage V1 which is an output voltage of the first converter unit 2 after a start-up of the high-pressure discharge lamp 100, based on a power source voltage detected by the power source voltage detection portion 45; and a variable control for varying the input voltage V1 set in the setting control, based on the lamp voltage V2 detected by the lamp voltage detection portion 42. <P>COPYRIGHT: (C)2012,JPO&INPIT |
