V. Zivcec, T. Ban, H. Skenderovic and G. Pichler
Institute of Physics, Zagreb, Croatia

High-pressure sodium sources of light have been spread all over the world despite the fact that color reproduction is relatively low. In addition, because of small amount of mercury in the discharge plasma, there is an environmental problem with the poisoning effect of the soil where the old lamps are stored.
In search for a better and nontoxic new light source we received pulsed high pressure cesium lamps of 80 Watt power. Color rendering index of this high-pressure cesium lamp is more than 95 (class 1A). In a usual pulsed regime the visible spectrum can be approximated with a Planck function for black body radiation at 3800 K [1,2]. Unfortunately, the efficiency of this high-pressure cesium discharge lamp has reached only 50 lumen/watt. We believe that the main cause of this might be a considerable loss in the infrared spectral region. Thus, the present application of high pressure pulsed cesium discharge lamp as a new light source is precluded.
The goal of a present research is to analyze spectra near UV, visible and infrared regions, in order to perform lamp tailoring with our knowledge of spectral phenomena in alkali plasmas [3-5]. We also believe that a few technical modifications are required to make this source of light more efficient. The new results will be presented and discussed.

REFERENCES:

[1] J.Liu, Ph. D. Thesis, Berlin (1998)
[2] H.Gu, M.E.Muzeroll, J.C. Chamberlain and J.Maya, Plasma Sources Sci. Technol. 10, 1(2001)
[3] D.Veža, R.Beuc, S.Miloševiæ, G.Pichler, Eur. Phy. J.D 2, 45(1998)
[4] T.Ban, H.Skenderoviæ, S.Ter-Avetisyan and G.Pichler, Appl.Phy. B, 72, 337(2001)
[5] R.Beuc, H.Skenderoviæ, T.Ban, D.Veža, G.Pichler and W.Meyer, Eur.Phys. J.D 15, 209(2001)