| 摘要 |
An intermediate electrode at a middle voltage which takes a value between a focusing voltage and an anode voltage is disposed between a focusing electrode and an anode of an in-line type electron gun. The intermediate electrode has a single opening whose diameter in the horizontal direction (in-line direction) is greater than the diameter thereof in the direction perpendicular to the horizontal direction so as to allow three electron beams to pass therethrough. The intermediate electrode also has a plate electrode provided therein with three electron beam apertures which respectively allow three electron beams to pass therethrough. Inside of the focusing electrode, a plate electrode provided with three electron beam apertures is provided. Here, the relationship between a length Lc which is obtained by adding diameters in the horizontal direction of three electron beam apertures and the lengths in the horizontal direction of bridges disposed between neighboring electron beam apertures of the plate electrode mounted in this focusing electrode and a length Lm which is obtained by adding diameters in the horizontal direction of three electron beam apertures and the lengths in the horizontal direction of bridges disposed between neighboring electron beam apertures of a plate electrode mounted in the intermediate electrode is set to Lc>Lm.
|
