| 摘要 |
<p>PURPOSE:To provide a fluorescent tube which is high in photo utilization coefficient with no reduction in resolving power due to chromatic aberration by disposing a reflecting mirror which is high in focusing property and is conductive at its surface, in the inside of the fluorescent tube. CONSTITUTION:A closed space made up out of a face glass 6 and a glass substrate 1 is maintained vacuous. A reflecting mirror (converging mirror) 8 furnished with focusing property is disposed in the closed space, and cathodes 7 and 7' are concurrently set while being in specified tension. The converging mirror 8 made of conductive material is formed integrally with a part of a grid electrode 5 at one side. In this case, the surface of the converging mirror 8 may be coated with conductive material such as aluminum, copper, silver and the like. The converging mirror 8 is formed integrally with the grid electrode 5, the mirror can thereby be provided with acceleration control function for electrons together with the conveging action of light coming from a fluorescent material 3.</p> |
