fernsehkameraroehre with bildwandlerteil and kathodenpotential stabilized bildelektrode

摘要

859,010. Television pick-up tubes. ENGLISH ELECTRIC VALVE CO. Ltd. July 27, 1959 [Sept. 9, 1958 ; Oct. 15, 1958], Nos. 28950/58 and 32908/58. Class 39(1). The optical image to be televised falls on a photoconductive layer of low specific resistivity backed by a transparent conductive electrode and connected thereto at a plurality of'a spaced area, a plurality of photoemissive elements being positioned on the other side of the photoconductive layer and arranged to be uniformly illuminated by light, the elements being connected to the photoconductive layer at areas none of which is opposite to the areas where that layer is connected to the electrode so as to give long current paths extending mainly in the plane of the layer. As shown in Fig. 2, light from the object passes through the transparent conductive electrode A2 on to the photoconductive layer A3 e.g. of cadmium selenide or sulphide or of lead telluride and the resulting changes in conductivity of that layer control the photoemission from a photoemissive layer A5 flooded by a source of light 13. The corresponding electron image passes through an equipotential grid 15 maintained at a fixed potential and falls on a secondaryemissive target 16 of high specific resistivity, secondary electrons from which are collected by grid 17 and which is scanned by an electron beam 8 to produce the picture signals at 5. Alternatively the photoconductive layer A3, Fig. 1, of the second Provisional Specification is covered by an Insulating layer A4 through which protrudes at spaced intervals an opaque metal layer A5 penetrated at A6 by photoemissive material. The conductive electrode A2 may be as shown or constituted by a conducting layer separated from the photoconductive layer A3 by discrete areas of insulating material. The first Provisional Specification discloses a photoconductive layer whose elemental areas are connected to a photoemissive layer by metal connectors extending through the intervening glass supporting.