| 摘要 |
PURPOSE:To prevent the lowering of the contrast of a picture displayed on a cathode ray tube due to the diffused reflection of external lights by radiating the luminescence from a fluorescent surface through the screens of an accelerating electrode and a controlling electrode and making the controlling electrode become black. CONSTITUTION:An electrode current 18 from a negative electrode 6 irradiates the whole fluorescent surface 17. The luminescence 19 from the whole fluorescent surface 17 is radiated to the outside of a cathode ray tube body 1 from the window 5 of an upper housing 2 through the screens of an accelerating electrode 12 and controlling electrode 7. An intensity modulation is performed by changing the potential of the controlling electrode 7. The controlling electrode 7 becomes black thereby the glaring due to the reflection of the sunlight is prevented. |
