| 摘要 |
PURPOSE:To maintain an exterior glass bulb at low temperature so as to enable a halogen lamp to be used widely by installing a small halogen lamp in the center of the internal space of the exterior bulb and evacuating the space between the exterior bulb and the halogen lamp. CONSTITUTION:After a small halogen lamp 2 charged with a halogen gas 9 is installed in the center of the internal space of an exterior glass bulb 1, a space 8 between the exterior bulb 1 and the small halogen lamp 2 is evacuated thereby constituting a halogen lamp of double structure. As a result, the halogen cycle of the small halogen lamp 2 can be carried out efficiently without increasing the temperature of the surrounding atmosphere. Besides, the exterior bulb 1 is maintained at low teperature by blocking thermal conduction, and it becomes possible to provide an infrared-ray absorbing film formed by vapordeposition on the exterior bulb 1. Consequently, irradiation of cool light without any infrared rays can be obtained easily. |
