Plasma Science: From Fundamental Research to Technological Applications (1995)
Chapter: LIGHTING
detail in the recent report of the National Research Council (NRC) Panel on Plasma Processing of Materials.1 The findings and recommendations of that study are summarized below in the section ''Plasma Processing of Materials.1 The findings and recommendations of that study are summarized below in the section "Plasma Processing of Materials."
LIGHTING
Lighting has been one of the principal areas contributing to the understanding of low-temperature plasmas, and historically it has been responsible for much of the low-temperature plasma research in industry. Unfortunately, due to the severe recession of the late 1980s and early 1990s, this research effort has declined rapidly. Westinghouse and GTE-Sylvania have sold their lighting divisions to foreign investors, leaving General Electric the only large U.S. lighting company. By contrast, low-temperature plasma research in the Far East has been increasing rapidly; it is now three to four times larger than that in the United States.
Important contributions from lighting in the past 10 years include the control and modification of the electron-energy distribution function and novel laser diagnostics that provide valuable microscopic information about discharge parameters. Other important contributions include sophisticated and predictive models of lighting discharges and an understanding of the effects of isotopic gas mixtures in low-pressure mercury rare-gas discharges.
Major technological innovations have been made in the last decade in many areas. They include lower-power compact fluorescent and high-intensity discharges (HID), a variety of electrodeless discharges such as microwave, rf, and surface wave discharges for practical lighting applications, and the electronic ballasting of light sources. Other important innovations include an improved understanding of heterogeneous chemistry, resulting in superior performance and better compatibility with existing and novel materials, and the development of a systems approach to light sources that integrates principles of plasma discharges, materials, electronics, and homogeneous and heterogeneous chemistry.
Although most of the R&D for lighting plasmas is performed by the lighting industry, the field has also benefited from advances in other disciplines. For example, solid-state, plasma processing, and materials advances made in other industries and in academic and research institutions have contributed to the progress in the lighting industry.
A fundamental understanding of many processes is necessary for the lighting industry to design and fabricate higher-efficiency lamps. Therefore, university and government research has and will continue to impact the industry. Areas of research include, for example, local thermodynamic equilibrium (LTE)
