| 摘要 |
<p>The bistable storage screen of the CRT eliminates the effect of halo with the peripheral zone of the screen featuring a layer over the fringe of the collector electrode. The layer extends to the collimation electrode, and its surface potential is lower than that of display zone of the screen, but is close to the potential of the cathode. In addition to conventional electrodes in the electron gun of the tube, the latter includes flood electron guns (34) which emit slow electrons and are set near the vertical deflection plates. Conductive layers (42, 44, 46, 48) on the wall of the tube ensure the focussing and collimation of the slow flood electrons and are fed with stepwise increased potentials, optimum operation being achieved when the highest positive voltage is at the electrode (42). This distributes the slow electrons uniformly over the screen. The screen electrode (52)of the tube face plate is formed by a film of tin oxide and is connected to the junction of resistors (58/60). The film is coated with a dielectric layer (56).</p> |
