Discharge Light Sources
As already outlined, electric discharge lamps are extremely common, with some two billion fluorescent lamps and 0.2 billion high intensity discharge (HID) lamps in service around the world (not counting USSR and mainland China), not to mention perhaps 5–10 million low-pressure sodium lamps. Taking 2500 lumens as the average light output per fluorescent lamp, and 15,000 lumens as the average light output per HID lamp, if all were lighted at once, about 8×1012 lumens would be generated. In turn, if this were distributed over the entire land area of the globe (7.2×1017 sq cm), the net illumination would be 10‒5 lumens/cm2, 0.1 lumens/m2 = 0.1 lux (ca 0.01 footcandle). This is about the illumination level of bright moonlight from a full moon.
KeywordsLife Cycle Cost Spectral Radiance Imprisonment Time Resonance Radiation Electrical Power Input
Unable to display preview. Download preview PDF.
- de Groot, J. J., 1974, Thesis, Tech. Univ. Eindhoven, Chapter III.Google Scholar
- Elenbaas, W., 1951, “The High Pressure Mercury Vapor Discharge”, North Holland Publishing Co., Amsterdam.Google Scholar
- Jones, B. F. and Mottram, D. A. J., 1981, J. Phys. D. Appl. Phys., 14:134.Google Scholar
- Keeffe, W. M., Krasko, Z. K. and Rothwell, H. L., 1985, in: “Proceedings Electrochem. Soc.”, 85–2:15.Google Scholar
- Rothwell, H. L. and Keeffe, V. M., 1980, J. Ilium, Eng. Soc., 10:40.Google Scholar
- van Tongeren, H., 1975, Philips Res. Rpts. Suppl. 3:1.Google Scholar
- Work, D. E. and Johnson, S. G., 1983, U.S. Patent No. 4,379,252.Google Scholar