| 摘要 |
<p>The high pressure sodium vapour discharge lamp has a refractory, transparent, tubular discharge tube, filled with sodium, mercury and a discharge starting gas. The sodium quantity is between 0. 007 to 0.054 mg and that of mercury 0.054 to 0.6 mg both per cn.cm of the discharge tube volume. The quantitative rating of sodium and mercury ensures complete vaporisation of both element during operation of the lamp. Preferred quantities are 0.007 to 0.018 mg for Na, and 0.1 to 0.6 for Hg. The end sections of the discharge tube (1) are typically surrounded by heat insulating sleeves (5) of refractory, insulating, sealing material. The latter is surrounded by fastening metal band (6).</p> |
