| 摘要 |
PURPOSE:To effectively improve brightness by inserting two grids or more between a filament and an anode and controlling applied voltage every grids. CONSTITUTION:A dot-type anode 2 divided into picture element units is formed at the center of the surface of a substrate 1 made of an insulating transparent body, for example, a glass plate and such along the longer direction and a phosphor 3 is formed on the surface of each anode 2 in a layer form. Several filaments 4 are hung above the phosphor 3 in the direction where they penetrate into the surface of paper and the first grid 5 and the second grid 6 are hung between the filament 4 and phosphor 3 in the direction where they penetrate into the surface of each paper. In addition, the anode 2, phosphor 4, filament 4, first grid 5, and second grid 6 are enclosed by a casing 7 and the inside of the casing 7 is preset to the vacuum state and then the respective different voltages can be applied to the anode 2, filament 4, first grid 5, second grid 6, etc. Especially, the respective applied voltage state can be controlled for the anode 2 every doe-type anodes by a drive circuit. |
