| 摘要 |
PURPOSE:To simply manufacture a discharge lamp with high mechanical strength and high emission efficiency by providing a double tube structure consisting of a cylindrical outer tube and noncircular cross sectional inner tube, arranging the inner tube between electrodes without sealing process, and using the inside of the inner tube as a discharge passage. CONSTITUTION:Metal caps 2 and 2' adhere to both ends of a cylindrical outer tube 1 and electrodes 3 and 3' are provided on these metal caps. On the other hand, the cross section of an inner tube 4 is rectangular or elliptical and the inner tube adheres to the inside of the outer tube 1. Both of its ends are opened and form a discharge passage. Therefore, the inside and outside of the inner tube 4 are always at the same pressure and free from the stress caused by the atmospheric pressure difference. The tube 4 is not damaged even if it has an extremely noncircular corss section. Besides, since discharge mainly takes place in this noncircular cross section, emission efficiency can be fully improved. |
