| Abstrakt: |
Tin chloride/tin iodide/sodium chloride/mercury discharges have been studied in two silica arc tube shapes of differing volume and dosing density. The particular parameters examined were the amount of added NaCl and the effective cool spot temperature of the discharge, the latter being varied by means of an electrically-controlled bath of molten indium. High luminous efficacies (100 lm W-1) were found, independent of the amount of added NaCl. Extensive spectral and colour measurements showed that the tendency for the addition of NaCl to lower the colour rendering index can be counteracted by increasing the cool spot temperature. A lamp combining Ra = 75, CCT = 3800K with a luminous efficacy of 90-100 lmW-1 is possible. The method can indicate trends in discharge behaviour without restriction to a particular embodiment. [ABSTRACT FROM PUBLISHER] |
