| 摘要 |
PURPOSE:To reduce the sight distance of a big display, which is constituted by using cathode-ray tubes as picture elements, by dividing the fluorescent screen of each cathode-ray tube used as a picture element into halves, and making one cathode-ray tube to emit light of two different primary colors. CONSTITUTION:The inner wall of a face part 3 provided at one end of a vacuum encircling case is divided into halves, and fluorescent screens 2a and 2b having different emission colors are provided on the divided inner walls of the part 3. Non-focusing electron beams 10a and 10b are discharged from positions facing to the screens 2a and 2b so that almost whole surfaces of the screens 2a and 2b can be irradiated by the electron beams 10a and 10b. Here, when a green and a red are constituted with a cathode-ray tube 31 and a green and a blue are constituted with a cathode-ray tube 32, the sight distance is reduced to the half since the sharpness of pictures is controlled by the green, and the red and the blue exist to tint the pictures. In addition, since the red and the green, with which the color shift becomes most noticeable, can be arranged close to each other, pictures much more easily seen than conventional ones can be obtained as to display of yellow color or the like. |
