| 摘要 |
1,216,496. Ionization manometers; electron multipliers. MULLARD Ltd. 21 June, 1968 [21 July, 1967], No. 33671/67. Heading H1D. An ionization high-vacuum gauge comprises an ionizer and a channel electron multiplier in the form of an electrically resistive tube with an open end adjacent the ionizer. The ionizer is formed by a pointed electrode 15, e.g. of lanthanum hexaboride, and the funnel-shaped end 14 of the multiplier. The multiplier 2 is a curved tube with a radius of curvature less than 24 times the radius of its bore and is made of lead glass with the surface facing the bore reduced to comprise a higher lead content than the remainder of the tube. The surface of the bore adjacent the input end is protected against ion bombardment by a layer of aluminium oxide, 100 Š thick. The output of the multiplier may be at 5 on a separate collector 10. The pressure range of the device is 10<SP>-8</SP> to 10<SP>-10</SP> Torr. |
