| 摘要 |
<p>A long life, halogen cycle, incandescent lamp (30) for operation in excess of 85 volts. The lamp comprises a transparent glass envelope (34) having sealed therewithin a tungsten filament (45); a pair of electrical lead-ins (42, 44) connecting the filament and extending exteriorly of the envelope for connection to a supply voltage greater than 100 V; and a fill gas within the envelope, including a halogen, at a pressure of at least three atmospheres. The envelope is constructed of a five component alkaline earth aluminosilicate glass having a composition consisting essentially of, in weight percent from > 58 to about 64 % SiO2, from about 14 to about 17 % Al2O3; from 0 to about 1 % B2O3, from 1 to about 6 % MgO, from about 6 to about 12 % CaO, from about 7 to about 17 % BaO and from 0 to about 1.5 % ZrO2.</p> |
