A method for sealing a plasma crucible, whereby the plasma crucible is an electrodeless illuminating apparatus powered by microwaves

摘要

594609 Disclosed is a method of sealing a plasma crucible (92) and a plasma crucible sealed in accordance with the method. The plasma crucible is suitable for use as a light source powered by microwave energy and is formed of a lucent material. The crucible has a through bore (93) and two tubes (981, 982) butt sealed on to the end faces (901, 902) of the crucible. The method of sealing the plasma crucible includes closing off one of the tubes by pinching off and the end is worked in a glass lathe to form it to have a flat end (983). An excitable solid material is then inserted into the through bore void, via the remaining open tube. Air is then evacuated from the void and an inert gas is then introduced into the void. After evacuation, dosing and gas fill, the remaining open tube is sealed by pinching off in a similar manner.