| 摘要 |
PROBLEM TO BE SOLVED: To provide a lighting device for discharge lamp which prevents aggravation of illumination environment of which a user is not conscious by suppressing luminous flux decline at the lower limit of light control, and promotes exchange of a lamp at an appropriate timing by reducing the light control range, and furthermore has good energy efficiency. SOLUTION: The discharge lamp lighting device 1 includes an inverter circuit 13 which supplies lighting power to a discharge lamp LA, a light control circuit 14 which adjusts optical output of the discharge lamp LA, and an illuminance correction circuit 15 which makes the lighting power constant at full lighting when the lighting power becomes maximum and raises the lighting power at the lower limit of light control of the light control range by the light control circuit 14 corresponding to luminous flux decline due to deterioration of the discharge lamp LA. Then, since the illuminance correction circuit 15 raises the lighting power at the lower limit of light control corresponding to the luminous flux decline, illuminance drop of the discharge lamp LA at the lower limit of light control is suppressed. COPYRIGHT: (C)2010,JPO&INPIT |
