Chiang teaches characterized in that the cross-sectional surface in said stem is shaped (see fig. 7); the concave part of the is said hollow structure (see fig. 5; hollow portion16+20 exhaust pipe) and the peak of the is a exhaust pipe (20 exhaust pipe),which is used in filling inert gases ([00031], [0006]) for heat dissipation into the bulb shell (10 lampshell) of the LED lamps (42 LED emitters).