| 摘要 |
890,626. Cathode-ray storage tubes. ENGLISH ELECTRIC VALVE CO. Ltd. Dec. 6, 1960 [Feb. 22, 1960], No. 6132/60. Class 39(1) A signal storage cathode-ray tube utilizes a foraminated storage electrode exhibiting the "Malter" thin film field emission effect. In a direct viewing storage tube the storage electrode 3 consists of a nickel or stainless steel mesh coated on the side facing the collector electrode 4 and gun 5 with a thin insulating layer of magnesium oxide, or of caesium oxide on alumina, and on the side facing the fluorescent screen 2, with a layer of field emission inhibiting material such as gold. The charge image is laid down on the storage electrode in consequence of the secondary emission arising under bombardment by the beam and as a result of the positive charge acquired by the storage electrode, field emission due to the Malter effect commences, the emitted electrons passing to the collector electrode. Some electrons, however are drawn through the interstices of the storage electrode to land on the fluorescent screen. The electron beam is switched on and off in accordance with the signals to be stored and displayed. The storage image may be erased by reducing the potential of the collector electrode or by increasing the potential of the storage electrode. The spacing between the storage electrode and the collector electrode and between the storage electrode and the screen may be 0.2 inch in each case. The voltages may be as shown. The electron gun 5 and the deflecting means may be replaced by a photo-cathode to produce a composite stream or the fluorescent screen may be replaced by a signal plate, a large continuous current being obtained from the signal plate in response to a transient signal applied to the electron gun. |
