| 摘要 |
<p>463,297. Cathode-ray tubes. MILLER, H. Sept. 24, 1935, No. 21883/36. Divided application. Drawings to Specification. [Class 39 (i)] A television transmitting tube comprises a photo-conductive screen on which an image is projected, a gun producing a scanning beam, and a secondary electron collecting electrode, and the screen material comprises zinc selenide. The screen may consist of mica coated with platinum, liquid silver (a suspension of colloidal gold and colloidal platinum in lavender oil) or gold-coated nickel, or of a metal disc, and the zinc selenide may be applied by spraying, sublimation, settling from suspension or chemical reaction on the screen. The screen may be transparent. A ring-shaped collector electrode connected to earth is arranged in front of the screen, which is biassed positively or negatively not more than 50 volts and preforably from 5 to 10 volts. The beam current should be from 1 to 10 microamps and the striking velocity from 1 to 2 kilovolts. The thickness of the screen should be less than the diameter of the scanning spot.</p> |
