| 摘要 |
PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device preventing an accumulated lighting time from being reset due to an incorrect operation of a power source switch or an unexpected abnormal signal. SOLUTION: When temporal reset operations (N1, N2) temporally resetting the accumulated lighting time are detected, a microcomputer of the discharge lamp lighting device starts to control an inverter circuit with an driving frequency corresponding to a case in which the accumulated lighting time is reset, and also starts measurement of discharge lamp lighting time Tsh2 after the temporal reset operation apart from the accumulated lighting time. When cancel operations (N3, N4) of a temporal reset state of the accumulated lighting time are detected before the measured time Tsh2 elapses a reset determination extension period (for example 1 hour), the microcomputer returns control of the inverter circuit to that referred to the accumulated lighting time. When the cancel operation is not detected until the measuring time Tsh2 elapses the reset determination extension period, reset of the accumulated lighting time recorded on a non-volatile memory is determined. COPYRIGHT: (C)2011,JPO&INPIT |
