摘要 |
An electrodeless lamp comprises an envelope containing a fill and a substance for facilitating the starting of the lamp. An outer tube is secured to an outside portion of the envelope in proximity to the given region and an inner tube is disposed within the outer tube such that a fluid passageway is defined between an inner surface of the outer tube and an outer surface of the inner tube. A hollow retractable electrode is provided within the inner tube, the electrode having a first position in which its tip portion is in proximity to the given region of the envelope when the lamp is being started and a second position in which the tip portion is away from the envelope after the lamp is started. A source of cooling fluid is operably connected to the hollow electrode such that the cooling fluid is forced through the hollow electrode and exhausted through the fluid passageway. A power source is operably connected to the electrode in the first position for applying an electric field to the substance to cause a discharge of the fill. An excitation power source is coupled to the fill to sustain the discharge. |