Fixture manufacturing began soon after production of the incandescent light bulb. However, the bulb emits the equivalent light of a four watt bulb. Lewis Howard Latimer invented an improvement for the incandescent light bulb. These were important developments in the history of the incandescent light bulb. Metal-halide lamps consist of an arc tube with electrodes, an outer bulb, and a base. One wonders whether the projector blew a light bulb. Light loss is due to filament evaporation and bulb blackening. Uses negative temperature compensation in the form of a light bulb or diode. The first US halogen headlamp bulb, introduced in 1983, was the HB1/9004. Instead, Edison got a patent on his improvements to the light bulb. ZappLight is a "2-in-1" LED light bulb and bug zapper. This was later discovered to be due to a burned-out light bulb. In 1981, she appeared in Woody Allen's "The Floating Light Bulb". In 1981 Allen's play "The Floating Light Bulb" opened on Broadway. The glass in such a bulb may be spherical or tubular.