HIGH-PRESSURE DISCHARGE LAMP LIGHTING DEVICE, HIGH-PRESSURE DISCHARGE LAMP DEVICE, PROJECTION TYPE IMAGE DISPLAY DEVICE, AND HIGH-PRESSURE DISCHARGE LAMP LIGHTING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a high-pressure discharge lamp lighting device capable of maintaining stability against subtle changes in color reproduction and brightness over a life-time period, through improvement of life characteristics affected by degradation of luminance. SOLUTION: The high-pressure mercury lamp and high-pressure discharge lamp lighting device is provided with a lighting circuit supplying alternating current for lighting to a high-pressure mercury lamp equipped with an arc tube with halogen substance sealed in and with a pair of electrodes arranged having their tip parts formed nearly in a pyramid shape, and with a protruded part formed at a tip part of the nearly pyramid shape, and a frequency control means for changing frequencies of the above alternating current without depending on operation data changing with lighting elapsed time of the high-pressure discharge lamp. The frequency control means changes frequencies the alternating current for each period between 340 Hz and 85 Hz without dependence on operation data changing with the lighting elapsed time. COPYRIGHT: (C)2008,JPO&INPIT