【摘要】 在真空技术中,四极场滤质器(QMF)已被最广泛地用作分析气体的工具。但直到目前为止,多数设计都只能得到“准双曲场”,即仅仅在靠近对称中心部分,其电位分布才满足理想四极场的关系。本文提出用两种形状的连续变电位封闭边界来产生严格的四极场。第一种方法是利用电位按COS2θ的关系作连续变化的圆形边界;第二种是利用电位按线性变化的正方形边界。它们都可以在所包含的面积内得到理想的四极场。具有规定截面形状的异形管,按需要的长度切断后即成为分析器。我们把这种分析器称为“魔管”。它具有较大的工作区比例、较低的加工精度要求,还存在着很多变型,及实际工作中有广泛使用的可能。更多还原

【Abstract】 The quadrupole mass filter (QMF) are widely used for gas analysis in vacuum technogy. But up to now, most commercially available electrostatic quadrupole systems were constructed by using four metallic circular rods in which only "quasi-hyperbolic fields" are available, i. e. the exact quadrupola field existed only in a small region in the vicinity of the center of symmetry.This paper described a new method for obtaining exact quadrupole fields within some closed boundaries on which a continuously varied potential is applied, the first strueture is a circular bounddary with potential varied accarding to cos 2θ; the second is a square or rectangular boundary on which potential is varied linearly with respect to the position. In practice these can be realized by a high-resistance tube with defined thickness in accordance with specified design criteria. This tube, termed as a "magic tube", can be cut into various lengths for making QMF analyzers. The method and structures can also be used for electron optical systems and related scientifie instruments.更多还原