| 摘要 |
PROBLEM TO BE SOLVED: To provide an ultra-high mercury lamp of 250 W class using Xe, in which the light intensity is balanced in a wavelength region near 248 nm and a wavelength region near 365 nm, and the maintenance factor of light intensity is high in respective wavelength regions within the life.SOLUTION: The amount of mercury in an ultra-high mercury lamp is set to 30-40 mg/cc, the inter-electrode distance G is set to 2.2-2.4 mm, Xe is enclosed as a rare-gas under pressure of 0.1-5.0 atm, the lamp current value is set in the range of 5.0-7.0 A when lighting, and the ultra-high mercury lamp is used while being connected with a constant power supply of 200-330 W. As a result, an ultraviolet ray maintenance factor of about 50% or more near 248 nm, and about 60% or more near 365 nm is obtained after elapsing 3000 hours. |
