| 摘要 |
<p>A low pressure sodium vapor lamp including a sodium vapor discharge tube within an outer envelope. The outer envelope is partially coated by a light reflector defining a light transmission aperture for desired directional light output. The outer envelope is additionally coated with an infrared reflective coating defining a heat transmission aperture at a location separate from the light transmission aperture. The heat transmission aperture acts as a heat sink. The area of the inner discharge tube corresponding to the heat transmission aperture thus becomes the coolest portion of the discharge tube, the "cold spot" of the lamp where excess sodium is condensed.</p> |
