| 摘要 |
PROBLEM TO BE SOLVED: To provide a small lighting device which is capable of making starting voltage of a discharge lamp a low level and surely and stably lighting a lamp with low voltage by properly and selectively controlling sticking of an enclosed object of the discharge lamp to an electrode. SOLUTION: Based on knowledge that higher at a starting time is required and emission of secondary electron becomes more difficult when depositions exist in the electrode of a discharge lamp as compared with when depositions do not exist, a heat insulating film 103 is provided on one electrode 101 of the lamp. When the lamp is turned off, cooling for the electrode 101 is delayed by the other electrode 102 and almost all evaporated enclosed objects are one-sidedly sticked to the electrode 102. By generating electric field by impressing starting pulse toward the electrode 101 where depositions do not exist from the electrode 102 in this state that a deposition D biasedly exists, aγaction is generated in the electrode 101 where depositions do not exist, emission efficiency of secondary electron is improved, a starting voltage level is suppressed to the low level and a starting pulse generation circuit can be miniaturized according to this suppression. |
