| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a discharge lamp lighting control device which prevents electrode melting of a discharge lamp at a time of a constant current controlling when starting up and realizes an extended service life of the discharge lamp. <P>SOLUTION: The discharge lamp lighting control device 10 is provided with a discharge lamp driving part 100 for driving a lamp 20 and a discharge lamp driving control part 400 which, after the lamp 20 starts lighting, carries out a constant current control so that a discharge lamp current flowing between both electrodes of the lamp 20 can be constant when a discharge lamp voltage applied between both electrodes of the lamp 20 is lower than a first predetermined voltage value, and carries out a constant power control so that a power supplied to the lamp 20 can be constant, when the discharge lamp voltage is higher than the first voltage value. The discharge lamp driving control part 400 is provided with a discharge lamp driving frequency control parts 410 and 440 which control so that a driving frequency, when the discharge lamp voltage is lower than the second predetermined voltage value which is lower than the first voltage value, can be lower than the frequency, when the discharge lamp voltage is higher than the second voltage value. <P>COPYRIGHT: (C)2008,JPO&INPIT |
