| 摘要 |
PURPOSE:To prevent the discoloration of displayed articles due to ultraviolet rays by mixing a ultraviolet ray depressant directly into a fluororesin film formed on the outer surface of a glass bulb. CONSTITUTION:A light emitting tube 5 made of quartz glass is stored in the outer tube bulb 1 of a metal halide lamp, and electrodes 6, 6 are sealed inside both ends of the light emitting tube 5. A fluororesin film 12 is formed over the whole outer surface of the outer tube glass 1. A ultraviolet ray depressant made of at least one kind of titanium oxide and zinc oxide is mixed into the fluororesin film 12, thus the ultraviolet ray depressant restricts the permeation of ultraviolet rays. When this lamp is used for the illumination of displayed articles at a shop, the emission of ultraviolet rays from this lamp can be reduced, and the discoloration of the displayed articles due to ultraviolet rays can be prevented. |
