| 摘要 |
PURPOSE:To prevent an unstable arc resulting from an acoustic resonance event generated at the high frequency lighting of a high pressure discharge lamp by making at least the one end of the luminous tube of the high pressure lamp thicker than the central part of the tube. CONSTITUTION:A high pressure discharge lamp is formed with quartz glass and such by supporting a luminous tube 1 using fixing tools 6a and 6b and being housed in an outer tube 7. In addition, the end of the luminous tube 1 is made thicker than the central part of the tube and electrodes 2a and 2b are positioned inside from the thicker tube end. As a result, a resonance event generated due to the existence of standing waves when the natural frequency determined by the shape of the luminous tube and sealing materials and the pressure variation at the inner part of the luminous tube that depends on the time change of input power are matched can be prevented since the higher components of sound pressure can be collected to the thicker section. Also, an unstable arc at the high frequency lighting can be prevented and the fluctuations, flickering out, and such of arc poles can be eliminated. |
