| 摘要 |
PURPOSE:To prevent any difference between the light outputs of the central and the peripheral parts of a fluorescent screen included in a shadow-mask-type color Braun tube by providing phosphor elements so that their emissional areas increase gradually from the central part to the peripheral part of the panel. CONSTITUTION:A color Braun tube is constituted by use of a fluorescent screen which consists of a number of phosphor elements, which are provided on a panel surface and exhibit different emissional colors by receiving stimulations of electron beams, and a black matter which fills the spaces formed between the above phosphor elements. Here, when the sizes of phosphor elements at the central part of the screen are supposed to be 100, the sizes of phosphor elements at the peripheral part of the screen are adjusted to the range between 90 and 110, thereby increasing the emissional area gradually from the central part to the peripheral part. As a result, any difference between the light outputs of the central part and the peripheral part of the fluorescent screen can be prevented without giving any influence upon a picture image. Besides, the visual discomfort of an observer which might be caused when the color Braun tube is used for display of letters or figures can be removed. |
