| 摘要 |
1,228,180. Cathode-ray tubes. INTERNATIONAL STANDARD ELECTRIC CORP. 7 Aug., 1968 [10 Aug., 1967], No. 37639/68. Heading HID. A storage target for an image orthicon or the like comprises a conductive mesh 18 coated to a thickness of one to fifty microns with a silicon oxide 20 to which is fixed an imperforate sheet 17 of, dielectric material having a thickness of about one tenth of a micron. The mesh may be of nickel, copper, silver or gold, or alloys thereof and has at least 500 and preferably 1000-2000 lines per inch. The coating 20 may be of silicon monoxide or of silicon dioxide and may be evaporated on to the mesh; the sheet 17 may be of silicon monoxide, silicon dioxide, aluminium oxide, pottassium chloride, sodium bromide, or magnesium oxide. In one method of manufacture an electroformed sheet of Al 2 O 3 650 Š thick is supported on a water surface above the coated mesh, and lowered on to it by draining away the water. In another method, a drop of lacquer is placed on the water surface, and a film of silicon monoxide is evaporated on to the lacquer; the water is drained to allow the film to descend on to the coated mesh, after which the target is baked to remove the lacquer. Since the storage target is very thin it may be disposed very near a photo-cathode and operated at a low (100-500 volts) or zero accelerating voltage relative to it to achieve proximity focusing. |
