| 摘要 |
PURPOSE:To stably turn on a lamp without a flicker, by turning on the lamp mainly emitting light of argon with at least a high frequency limit current corresponding to seal pressure of the lamp. CONSTITUTION:A low pressure rare gas discharge lamp is constituted such that argon or mixed gas containing argon and consisting of the rest part of at least one of neon or helium is sealed in a discharge lamp vessel not lower than 1Torr and not higher than 8Torr to mainly emit light of argon, and this gas discharge lamp is turned on by a high frequency lighting device with a frequency at least 5kHz further with a current peak value Iop(A) (O-peak current) Iop >=1.8/P0.7 for seal pressure P(Torr) of the gas discharge lamp. Pressure of seal gas less than 1Torr is unsuitable because an electrode decreases its life further with a large limit current, while the pressure exceeding 8Torr is unsuitable because luminous efficiency decreases. Further a lighting frequency of the lighting device, if low, is considered to cause a change of ion density and change the limit current. |
