| 摘要 |
PURPOSE:To control accurately the position of an electron beam relative to a phosphor stripe by providing index dots made of two kinds of phosphors emitting different optical rays, respectively, on the back surfaces of non-emissional stripes and phosphor stripes. CONSTITUTION:Phosphor stripes 11R, 11B and 11G and non-emissional stripes 10 are provided alternately on the inner surface of a panel 2. Index dots 13 made of a first phosphor member are provided on the back surface of the panel 2 in such a manner that the dots of each line are arranged at a pitch of (P) correspondingly to each non-emissional stripe 10 and that there is a deviation of (1/3P) between the dots of adjacent lines. In addition, reference index dots 14 made of a second phosphor member are arranged at a pitch of (P) correspondingly to the phosphor stripes 11. As a result, a scanning beam can be made to travel accurately on a specified phosphor stripe without protruding from it by comparing the phases of the dots 13 and 14 by detecting the light of the dots 13 and 14 by means of detectors 20 and 21. |
