| 摘要 |
<p>A metal halide lamp including a discharge tube (1) of a transparent ceramic in which a discharge metal and a buffer gas are sealed, the discharge tube (1) having electrodes (12) at both ends thereof, including a discharge portion, slender tube portions (19) provided at both ends of the discharge portion, into which feedthroughs (2a) including the electrodes (12) and lead-in wires (11) are inserted, and slender tube sealing portions (5) in which gaps between the slender tube portions (19) and the feedthroughs (20) are sealed with a sealing material (10), an outer tube (2) containing the discharge tube (1), and a transparent protecting cylinder (3) provided inside the outer tube (2) so as to surround the discharge tube (1) is provided. At least one of the slender tube sealing portions (5) is exposed beyond the protecting cylinder (3). This provides a metal halide lamp that suppresses leaks in a discharge tube sealing portion while maintaining high efficiency and high colour rendition by using a ceramic discharge tube (1), and that is tolerant to an external shock.</p> |
