| 摘要 |
PROBLEM TO BE SOLVED: To provide a discharge lamp device capable of reliably detecting abnormal lighting of a discharge lamp and thus capable of preventing the occurrence of an accident due to abnormal lighting of the discharge lamp. SOLUTION: The discharge lamp device includes a lamp lighting state-monitoring mechanism functioning as follows: the lamp lighting state-monitoring mechanism stores, at every sequential measure-target time point, measured values of lamp power and lamp voltage measured at measure-target time points set at every predetermined short time-period interval. When the lighting state of the discharge lamp is changed, using any measured value measured in a time period when the discharge lamp is lit immediately before the shift as a reference measured value of the lamp power and a reference measured value of the lamp voltage, the lamp lighting state-monitoring mechanism emits an abnormal lighting detection signal on detecting that the increase/decrease tendency of the measured value of the lamp power at a latest measure-target time point after the change of the lamp lighting state to the reference measured value of the lamp power conflicts with the increase/decrease tendency of the measured value of the lamp voltage at the latest measure-target time point to the reference measured value of the lamp voltage. COPYRIGHT: (C)2011,JPO&INPIT |
