| 摘要 |
PURPOSE:To obtain a fidelity color image by providing an index fluorescent stripe for detecting a beam position externally of an effective screen area, and switching the timing of a color signal applied to a G1 electrode with use of an index signal available from said fluorescent stripe. CONSTITUTION:R, G, and B fluorescent striped 40 are respectively provided on an effective screen area A, while am index fluorescent material 42 if formed in the same pitch as that of the fluorescent stripes on an outside area B of said screen area. In addition, a cathode and a G1 electrode 53a corresponding to the area A as well as a cathode 50B and the G1 electrode 53b corresponding to the area B are provided separated away from each other, and combined with a G2 electrode 54, a G3 electrode 55, a G4 electrode 56, a horizontal focusing electrode 57, and a horizontal deflection electrode 58 from forming a plate type color CRT. Accordingly, a fidelity color reproduction image can be yielded by detecting an index signal with use of a photoelectric converting element 46 for each cathode block and for thereby controlling a beam modulation signal from the effective screen. |
