HIGH INTENSITY DISCHARGE LAMPS, ARC TUBES AND METHODS OF MANUFACTURE

摘要

A method of filling an arc tube (12) with a fill gas, the arc tube having an open end (16) in fluid communication with an uncontrolled atmosphere surrounding the arc tube comprising an optional step of flushing the tube with a flush gas, providing a fill gas cooling the lower section (12) of the tube to cool a portion of the fill gas and sealing the tube while the fill gas is at a reduced temperature and the tube is open to the atmosphere so that the fill gas will be at a superatmospheric pressure when the temperature of the fill gas is no longer reduced. An embodiment is disclosed wherein the fill gas includes argon and xenon and the temperature is below the freezing point of xenon but above the freezing point of argon. Another embodiment discloses providing a blanket of non -reactive gas between the fill gas and the atmosphere. Further embodiments are disclosed including a step of pinch sealing the lower end of the tube and introducing the lamp fill material, mercury and an inert gas into the chamber through the other end portion.