| 摘要 |
PROBLEM TO BE SOLVED: To provide a light source allowing the easy constitution of the light source of disc shape or cylindrical shape, eliminating the brightness unevenness of an outer tube when lighted and having uniform brightness over the whole surface of an outer tube luminescent part. SOLUTION: An upper plate and a lower plate are vertically arranged with a small clearance, or an outer cylinder and an inner cylinder are arranged with the same center axis, and a plane like or curved surface like space surrounded by both plates or cylinders is made an electric discharge space to constitute the lamp. The lower plate or the inner cylinder is provided with one or more pairs of anodes and cathodes alternately in spiral shape or linear shape while holding a constant space, and voltage of high frequency or the like is applied to both electrodes to allow the surface discharge of the outer tube luminescent part. |
